refactor: convert function expressions to declarations (#4926)

.eslintrc.js

@@ -30,6 +30,7 @@ module.exports = {
     '@emotion/styled-import': 'error',
     'require-atomic-updates': [0],
     'object-shorthand': ['error', 'always'],
+    'func-style': ['error', 'declaration'],
     'prefer-const': [
       'error',
       {

babel.config.js

@@ -74,7 +74,7 @@ const defaultPlugins = [
   ],
 ];
 
-const presets = () => {
+function presets() {
   return [
     '@babel/preset-react',
     '@babel/preset-env',
@@ -86,9 +86,9 @@ const presets = () => {
     ],
     '@babel/typescript',
   ];
-};
+}
 
-const plugins = () => {
+function plugins() {
   if (isESM) {
     return [
       ...defaultPlugins,
@@ -129,7 +129,7 @@ const plugins = () => {
   }
 
   return defaultPlugins;
-};
+}
 
 module.exports = {
   presets: presets(),

packages/netlify-cms-backend-azure/src/API.ts

@@ -161,7 +161,7 @@ function delay(ms: number) {
   return new Promise(resolve => setTimeout(resolve, ms));
 }
 
-const getChangeItem = (item: AzureCommitItem) => {
+function getChangeItem(item: AzureCommitItem) {
   switch (item.action) {
     case AzureCommitChangeType.ADD:
       return {
@@ -195,7 +195,7 @@ const getChangeItem = (item: AzureCommitItem) => {
     default:
       return {};
   }
-};
+}
 
 type AzureCommitItem = {
   action: AzureCommitChangeType;

packages/netlify-cms-backend-azure/src/implementation.ts

@@ -33,7 +33,7 @@ import {
 
 const MAX_CONCURRENT_DOWNLOADS = 10;
 
-const parseAzureRepo = (config: Config) => {
+function parseAzureRepo(config: Config) {
   const { repo } = config.backend;
 
   if (typeof repo !== 'string') {
@@ -51,7 +51,7 @@ const parseAzureRepo = (config: Config) => {
     project,
     repoName,
   };
-};
+}
 
 export default class Azure implements Implementation {
   lock: AsyncLock;

packages/netlify-cms-backend-bitbucket/src/API.ts

@@ -186,14 +186,14 @@ export const API_NAME = 'Bitbucket';
 
 const APPLICATION_JSON = 'application/json; charset=utf-8';
 
-const replace404WithEmptyResponse = (err: FetchError) => {
+function replace404WithEmptyResponse(err: FetchError) {
   if (err && err.status === 404) {
     console.log('This 404 was expected and handled appropriately.');
     return { size: 0, values: [] as BitBucketFile[] } as BitBucketSrcResult;
   } else {
     return Promise.reject(err);
   }
-};
+}
 
 export default class API {
   apiRoot: string;

packages/netlify-cms-backend-git-gateway/src/implementation.ts

@@ -121,11 +121,11 @@ interface NetlifyUser extends Credentials {
   user_metadata: { full_name: string; avatar_url: string };
 }
 
-const apiGet = async (path: string) => {
+async function apiGet(path: string) {
   const apiRoot = 'https://api.netlify.com/api/v1/sites';
   const response = await fetch(`${apiRoot}/${path}`).then(res => res.json());
   return response;
-};
+}
 
 export default class GitGateway implements Implementation {
   config: Config;

packages/netlify-cms-backend-git-gateway/src/netlify-lfs-client.ts

@@ -15,8 +15,9 @@ type ClientConfig = {
   transformImages: ImageTransformations | boolean;
 };
 
-export const matchPath = ({ patterns }: ClientConfig, path: string) =>
+export function matchPath({ patterns }: ClientConfig, path: string) {
-  patterns.some(pattern => minimatch(path, pattern, { matchBase: true }));
+  return patterns.some(pattern => minimatch(path, pattern, { matchBase: true }));
+}
 
 //
 // API interactions
@@ -26,10 +27,10 @@ const defaultContentHeaders = {
   ['Content-Type']: 'application/vnd.git-lfs+json',
 };
 
-const resourceExists = async (
+async function resourceExists(
   { rootURL, makeAuthorizedRequest }: ClientConfig,
   { sha, size }: PointerFile,
-) => {
+) {
   const response = await makeAuthorizedRequest({
     url: `${rootURL}/verify`,
     method: 'POST',
@@ -45,20 +46,20 @@ const resourceExists = async (
 
   // TODO: what kind of error to throw here? APIError doesn't seem
   // to fit
-};
+}
 
-const getTransofrmationsParams = (t: boolean | ImageTransformations) => {
+function getTransofrmationsParams(t: boolean | ImageTransformations) {
   if (isPlainObject(t) && !isEmpty(t)) {
     const { nf_resize: resize, w, h } = t as ImageTransformations;
     return `?nf_resize=${resize}&w=${w}&h=${h}`;
   }
   return '';
-};
+}
 
-const getDownloadURL = async (
+async function getDownloadURL(
   { rootURL, transformImages: t, makeAuthorizedRequest }: ClientConfig,
   { sha }: PointerFile,
-) => {
+) {
   try {
     const transformation = getTransofrmationsParams(t);
     const transformedPromise = makeAuthorizedRequest(`${rootURL}/origin/${sha}${transformation}`);
@@ -81,21 +82,23 @@ const getDownloadURL = async (
     console.error(error);
     return { url: '', blob: new Blob() };
   }
-};
+}
 
-const uploadOperation = (objects: PointerFile[]) => ({
+function uploadOperation(objects: PointerFile[]) {
+  return {
     operation: 'upload',
     transfers: ['basic'],
     objects: objects.map(({ sha, ...rest }) => ({ ...rest, oid: sha })),
-});
+  };
+}
 
-const getResourceUploadURLs = async (
+async function getResourceUploadURLs(
   {
     rootURL,
     makeAuthorizedRequest,
   }: { rootURL: string; makeAuthorizedRequest: MakeAuthorizedRequest },
   pointerFiles: PointerFile[],
-) => {
+) {
   const response = await makeAuthorizedRequest({
     url: `${rootURL}/objects/batch`,
     method: 'POST',
@@ -113,19 +116,20 @@ const getResourceUploadURLs = async (
     },
   );
   return uploadUrls;
-};
+}
 
-const uploadBlob = (uploadURL: string, blob: Blob) =>
+function uploadBlob(uploadURL: string, blob: Blob) {
-  unsentRequest.fetchWithTimeout(uploadURL, {
+  return unsentRequest.fetchWithTimeout(uploadURL, {
     method: 'PUT',
     body: blob,
   });
+}
 
-const uploadResource = async (
+async function uploadResource(
   clientConfig: ClientConfig,
   { sha, size }: PointerFile,
   resource: Blob,
-) => {
+) {
   const existingFile = await resourceExists(clientConfig, { sha, size });
   if (existingFile) {
     return sha;
@@ -133,13 +137,14 @@ const uploadResource = async (
   const [uploadURL] = await getResourceUploadURLs(clientConfig, [{ sha, size }]);
   await uploadBlob(uploadURL, resource);
   return sha;
-};
+}
 
 //
 // Create Large Media client
 
-const configureFn = (config: ClientConfig, fn: Function) => (...args: unknown[]) =>
+function configureFn(config: ClientConfig, fn: Function) {
-  fn(config, ...args);
+  return (...args: unknown[]) => fn(config, ...args);
+}
 
 const clientFns: Record<string, Function> = {
   resourceExists,
@@ -159,7 +164,7 @@ export type Client = {
   enabled: boolean;
 };
 
-export const getClient = (clientConfig: ClientConfig) => {
+export function getClient(clientConfig: ClientConfig) {
   return flow([
     Object.keys,
     map((key: string) => [key, configureFn(clientConfig, clientFns[key])]),
@@ -170,4 +175,4 @@ export const getClient = (clientConfig: ClientConfig) => {
       enabled: clientConfig.enabled,
     }),
   ])(clientFns);
-};
+}

packages/netlify-cms-backend-github/src/API.ts

@@ -129,12 +129,15 @@ type MediaFile = {
   path: string;
 };
 
-const withCmsLabel = (pr: GitHubPull, cmsLabelPrefix: string) =>
+function withCmsLabel(pr: GitHubPull, cmsLabelPrefix: string) {
-  pr.labels.some(l => isCMSLabel(l.name, cmsLabelPrefix));
+  return pr.labels.some(l => isCMSLabel(l.name, cmsLabelPrefix));
-const withoutCmsLabel = (pr: GitHubPull, cmsLabelPrefix: string) =>
+}
-  pr.labels.every(l => !isCMSLabel(l.name, cmsLabelPrefix));
 
-const getTreeFiles = (files: GitHubCompareFiles) => {
+function withoutCmsLabel(pr: GitHubPull, cmsLabelPrefix: string) {
+  return pr.labels.every(l => !isCMSLabel(l.name, cmsLabelPrefix));
+}
+
+function getTreeFiles(files: GitHubCompareFiles) {
   const treeFiles = files.reduce((arr, file) => {
     if (file.status === 'removed') {
       // delete the file
@@ -152,7 +155,7 @@ const getTreeFiles = (files: GitHubCompareFiles) => {
   }, [] as { sha: string | null; path: string }[]);
 
   return treeFiles;
-};
+}
 
 export type Diff = {
   path: string;
@@ -446,7 +449,7 @@ export default class API {
       headers: { Accept: 'application/vnd.github.v3.raw' },
     };
 
-    const errorHandler = (err: Error) => {
+    function errorHandler(err: Error) {
       if (err.message === 'Not Found') {
         console.log(
           '%c %s does not have metadata',
@@ -455,7 +458,7 @@ export default class API {
         );
       }
       throw err;
-    };
+    }
 
     if (!this.useOpenAuthoring) {
       const result = await this.request(

packages/netlify-cms-backend-github/src/GraphQLAPI.ts

@@ -69,14 +69,14 @@ type GraphQLPullRequest = {
   };
 };
 
-const transformPullRequest = (pr: GraphQLPullRequest) => {
+function transformPullRequest(pr: GraphQLPullRequest) {
   return {
     ...pr,
     labels: pr.labels.nodes,
     head: { ref: pr.headRefName, sha: pr.headRefOid, repo: { fork: pr.repository.isFork } },
     base: { ref: pr.baseRefName, sha: pr.baseRefOid },
   };
-};
+}
 
 type Error = GraphQLError & { type: string };
 

packages/netlify-cms-backend-github/src/__tests__/API.spec.js

@@ -8,7 +8,7 @@ describe('github API', () => {
     jest.resetAllMocks();
   });
 
-  const mockAPI = (api, responses) => {
+  function mockAPI(api, responses) {
     api.request = jest.fn().mockImplementation((path, options = {}) => {
       const normalizedPath = path.indexOf('?') !== -1 ? path.substr(0, path.indexOf('?')) : path;
       const response = responses[normalizedPath];
@@ -16,7 +16,7 @@ describe('github API', () => {
         ? Promise.resolve(response(options))
         : Promise.reject(new Error(`No response for path '${normalizedPath}'`));
     });
-  };
+  }
 
   describe('editorialWorkflowGit', () => {
     it('should create PR with correct base branch name when publishing with editorial workflow', () => {

packages/netlify-cms-backend-github/src/queries.ts

@@ -62,7 +62,7 @@ export const statues = gql`
   ${fragments.object}
 `;
 
-const buildFilesQuery = (depth = 1) => {
+function buildFilesQuery(depth = 1) {
   const PLACE_HOLDER = 'PLACE_HOLDER';
   let query = oneLine`
     ...ObjectParts
@@ -93,9 +93,10 @@ const buildFilesQuery = (depth = 1) => {
   query = query.replace(PLACE_HOLDER, '');
 
   return query;
-};
+}
 
-export const files = (depth: number) => gql`
+export function files(depth: number) {
+  return gql`
     query files($owner: String!, $name: String!, $expression: String!) {
       repository(owner: $owner, name: $name) {
         ...RepositoryParts
@@ -107,7 +108,8 @@ export const files = (depth: number) => gql`
     ${fragments.repository}
     ${fragments.object}
     ${fragments.fileEntry}
-`;
+  `;
+}
 
 const branchQueryPart = `
 branch: ref(qualifiedName: $qualifiedName) {

packages/netlify-cms-backend-gitlab/src/API.ts

@@ -171,14 +171,14 @@ type GitLabCommit = {
   message: string;
 };
 
-export const getMaxAccess = (groups: { group_access_level: number }[]) => {
+export function getMaxAccess(groups: { group_access_level: number }[]) {
   return groups.reduce((previous, current) => {
     if (current.group_access_level > previous.group_access_level) {
       return current;
     }
     return previous;
   }, groups[0]);
-};
+}
 
 export default class API {
   apiRoot: string;

packages/netlify-cms-backend-gitlab/src/__tests__/gitlab.spec.js

@@ -8,7 +8,7 @@ import AuthenticationPage from '../AuthenticationPage';
 
 const { Backend, LocalStorageAuthStore } = jest.requireActual('netlify-cms-core/src/backend');
 
-const generateEntries = (path, length) => {
+function generateEntries(path, length) {
   const entries = Array.from({ length }, (val, idx) => {
     const count = idx + 1;
     const id = `00${count}`.slice(-3);
@@ -37,7 +37,7 @@ const generateEntries = (path, length) => {
       {},
     ),
   };
-};
+}
 
 const manyEntries = generateEntries('many-entries', 500);
 
@@ -222,8 +222,10 @@ describe('gitlab backend', () => {
     const pageNum = parseInt(page, 10);
     const pageCountNum = parseInt(pageCount, 10);
     const url = `${backend.implementation.apiRoot}${basePath}`;
-    const link = linkPage =>
+
-      `<${url}?id=${expectedRepo}&page=${linkPage}&path=${path}&per_page=${perPage}&recursive=false>`;
+    function link(linkPage) {
+      return `<${url}?id=${expectedRepo}&page=${linkPage}&path=${path}&per_page=${perPage}&recursive=false>`;
+    }
 
     const linkHeader = oneLine`
       ${link(1)}; rel="first",

packages/netlify-cms-backend-proxy/src/implementation.ts

@@ -14,11 +14,10 @@ import {
 } from 'netlify-cms-lib-util';
 import AuthenticationPage from './AuthenticationPage';
 
-const serializeAsset = async (assetProxy: AssetProxy) => {
+async function serializeAsset(assetProxy: AssetProxy) {
   const base64content = await assetProxy.toBase64!();
-
   return { path: assetProxy.path, content: base64content, encoding: 'base64' };
-};
+}
 
 type MediaFile = {
   id: string;
@@ -28,7 +27,7 @@ type MediaFile = {
   path: string;
 };
 
-const deserializeMediaFile = ({ id, content, encoding, path, name }: MediaFile) => {
+function deserializeMediaFile({ id, content, encoding, path, name }: MediaFile) {
   let byteArray = new Uint8Array(0);
   if (encoding !== 'base64') {
     console.error(`Unsupported encoding '${encoding}' for file '${path}'`);
@@ -43,7 +42,7 @@ const deserializeMediaFile = ({ id, content, encoding, path, name }: MediaFile)
   const file = blobToFileObj(name, blob);
   const url = URL.createObjectURL(file);
   return { id, name, path, file, size: file.size, url, displayURL: url };
-};
+}
 
 export default class ProxyBackend implements Implementation {
   proxyUrl: string;

packages/netlify-cms-backend-test/src/implementation.ts

@@ -74,13 +74,13 @@ function deleteFile(path: string, tree: RepoTree) {
 
 const pageSize = 10;
 
-const getCursor = (
+function getCursor(
   folder: string,
   extension: string,
   entries: ImplementationEntry[],
   index: number,
   depth: number,
-) => {
+) {
   const count = entries.length;
   const pageCount = Math.floor(count / pageSize);
   return Cursor.create({
@@ -91,16 +91,16 @@ const getCursor = (
     meta: { index, count, pageSize, pageCount },
     data: { folder, extension, index, pageCount, depth },
   });
-};
+}
 
-export const getFolderFiles = (
+export function getFolderFiles(
   tree: RepoTree,
   folder: string,
   extension: string,
   depth: number,
   files = [] as RepoFile[],
   path = folder,
-) => {
+) {
   if (depth <= 0) {
     return files;
   }
@@ -118,7 +118,7 @@ export const getFolderFiles = (
   });
 
   return files;
-};
+}
 
 export default class TestBackend implements Implementation {
   mediaFolder: string;

packages/netlify-cms-core/src/actions/__tests__/config.spec.js

@@ -817,14 +817,14 @@ describe('config', () => {
   });
 
   describe('detectProxyServer', () => {
-    const assetFetchCalled = (url = 'http://localhost:8081/api/v1') => {
+    function assetFetchCalled(url = 'http://localhost:8081/api/v1') {
       expect(global.fetch).toHaveBeenCalledTimes(1);
       expect(global.fetch).toHaveBeenCalledWith(url, {
         method: 'POST',
         headers: { 'Content-Type': 'application/json' },
         body: JSON.stringify({ action: 'info' }),
       });
-    };
+    }
 
     beforeEach(() => {
       delete window.location;

packages/netlify-cms-core/src/actions/config.js

@@ -13,7 +13,7 @@ export const CONFIG_REQUEST = 'CONFIG_REQUEST';
 export const CONFIG_SUCCESS = 'CONFIG_SUCCESS';
 export const CONFIG_FAILURE = 'CONFIG_FAILURE';
 
-const traverseFieldsJS = (fields, updater) => {
+function traverseFieldsJS(fields, updater) {
   return fields.map(field => {
     let newField = updater(field);
     if (newField.fields) {
@@ -26,9 +26,9 @@ const traverseFieldsJS = (fields, updater) => {
 
     return newField;
   });
-};
+}
 
-const getConfigUrl = () => {
+function getConfigUrl() {
   const validTypes = { 'text/yaml': 'yaml', 'application/x-yaml': 'yaml' };
   const configLinkEl = document.querySelector('link[rel="cms-config-url"]');
   const isValidLink = configLinkEl && validTypes[configLinkEl.type] && get(configLinkEl, 'href');
@@ -38,14 +38,14 @@ const getConfigUrl = () => {
     return link;
   }
   return 'config.yml';
-};
+}
 
-const setDefaultPublicFolder = map => {
+function setDefaultPublicFolder(map) {
   if (map.has('media_folder') && !map.has('public_folder')) {
     map = map.set('public_folder', map.get('media_folder'));
   }
   return map;
-};
+}
 
 // Mapping between existing camelCase and its snake_case counterpart
 const WIDGET_KEY_MAP = {
@@ -60,7 +60,7 @@ const WIDGET_KEY_MAP = {
   optionsLength: 'options_length',
 };
 
-const setSnakeCaseConfig = field => {
+function setSnakeCaseConfig(field) {
   const deprecatedKeys = Object.keys(WIDGET_KEY_MAP).filter(camel => camel in field);
   const snakeValues = deprecatedKeys.map(camel => {
     const snake = WIDGET_KEY_MAP[camel];
@@ -71,18 +71,18 @@ const setSnakeCaseConfig = field => {
   });
 
   return Object.assign({}, field, ...snakeValues);
-};
+}
 
-const setI18nField = field => {
+function setI18nField(field) {
   if (field.get(I18N) === true) {
     field = field.set(I18N, I18N_FIELD.TRANSLATE);
   } else if (field.get(I18N) === false || !field.has(I18N)) {
     field = field.set(I18N, I18N_FIELD.NONE);
   }
   return field;
-};
+}
 
-const setI18nDefaults = (defaultI18n, collectionOrFile) => {
+function setI18nDefaults(defaultI18n, collectionOrFile) {
   if (defaultI18n && collectionOrFile.has(I18N)) {
     const collectionOrFileI18n = collectionOrFile.get(I18N);
     if (collectionOrFileI18n === true) {
@@ -121,17 +121,17 @@ const setI18nDefaults = (defaultI18n, collectionOrFile) => {
     }
   }
   return collectionOrFile;
-};
+}
 
-const throwOnInvalidFileCollectionStructure = i18n => {
+function throwOnInvalidFileCollectionStructure(i18n) {
   if (i18n && i18n.get('structure') !== I18N_STRUCTURE.SINGLE_FILE) {
     throw new Error(
       `i18n configuration for files collections is limited to ${I18N_STRUCTURE.SINGLE_FILE} structure`,
     );
   }
-};
+}
 
-const throwOnMissingDefaultLocale = i18n => {
+function throwOnMissingDefaultLocale(i18n) {
   if (i18n && !i18n.get('locales').includes(i18n.get('default_locale'))) {
     throw new Error(
       `i18n locales '${i18n.get('locales').join(', ')}' are missing the default locale ${i18n.get(
@@ -139,9 +139,9 @@ const throwOnMissingDefaultLocale = i18n => {
       )}`,
     );
   }
-};
+}
 
-const setViewPatternsDefaults = (key, collection) => {
+function setViewPatternsDefaults(key, collection) {
   if (!collection.has(key)) {
     collection = collection.set(key, fromJS([]));
   } else {
@@ -152,17 +152,17 @@ const setViewPatternsDefaults = (key, collection) => {
   }
 
   return collection;
-};
+}
 
 const defaults = {
   publish_mode: SIMPLE_PUBLISH_MODE,
 };
 
-const hasIntegration = (config, collection) => {
+function hasIntegration(config, collection) {
   const integrations = getIntegrations(config);
   const integration = selectIntegration(integrations, collection.get('name'), 'listEntries');
   return !!integration;
-};
+}
 
 export function normalizeConfig(config) {
   const { collections = [] } = config;
@@ -390,7 +390,7 @@ export async function detectProxyServer(localBackend) {
   return {};
 }
 
-const getPublishMode = (config, publishModes, backendType) => {
+function getPublishMode(config, publishModes, backendType) {
   if (config.publish_mode && publishModes && !publishModes.includes(config.publish_mode)) {
     const newPublishMode = publishModes[0];
     console.log(
@@ -400,9 +400,9 @@ const getPublishMode = (config, publishModes, backendType) => {
   }
 
   return config.publish_mode;
-};
+}
 
-export const handleLocalBackend = async config => {
+export async function handleLocalBackend(config) {
   if (!config.local_backend) {
     return config;
   }
@@ -421,7 +421,7 @@ export const handleLocalBackend = async config => {
     ...(publishMode && { publish_mode: publishMode }),
     backend: { ...config.backend, name: 'proxy', proxy_url: proxyUrl },
   };
-};
+}
 
 export function loadConfig(manualConfig = {}, onLoad) {
   if (window.CMS_CONFIG) {

packages/netlify-cms-core/src/actions/entries.ts

@@ -154,7 +154,7 @@ export function entriesFailed(collection: Collection, error: Error) {
   };
 }
 
-const getAllEntries = async (state: State, collection: Collection) => {
+async function getAllEntries(state: State, collection: Collection) {
   const backend = currentBackend(state.config);
   const integration = selectIntegration(state, collection.get('name'), 'listEntries');
   const provider: Backend = integration
@@ -162,7 +162,7 @@ const getAllEntries = async (state: State, collection: Collection) => {
     : backend;
   const entries = await provider.listAllEntries(collection);
   return entries;
-};
+}
 
 export function sortByField(
   collection: Collection,
@@ -555,7 +555,7 @@ const appendActions = fromJS({
   ['append_next']: { action: 'next', append: true },
 });
 
-const addAppendActionsToCursor = (cursor: Cursor) => {
+function addAppendActionsToCursor(cursor: Cursor) {
   return Cursor.create(cursor).updateStore('actions', (actions: Set<string>) => {
     return actions.union(
       appendActions
@@ -563,7 +563,7 @@ const addAppendActionsToCursor = (cursor: Cursor) => {
         .keySeq(),
     );
   });
-};
+}
 
 export function loadEntries(collection: Collection, page = 0) {
   return async (dispatch: ThunkDispatch<State, {}, AnyAction>, getState: () => State) => {
@@ -692,16 +692,16 @@ export function traverseCollectionCursor(collection: Collection, action: string)
   };
 }
 
-const escapeHtml = (unsafe: string) => {
+function escapeHtml(unsafe: string) {
   return unsafe
     .replace(/&/g, '&amp;')
     .replace(/</g, '&lt;')
     .replace(/>/g, '&gt;')
     .replace(/"/g, '&quot;')
     .replace(/'/g, '&#039;');
-};
+}
 
-const processValue = (unsafe: string) => {
+function processValue(unsafe: string) {
   if (['true', 'True', 'TRUE'].includes(unsafe)) {
     return true;
   }
@@ -710,10 +710,15 @@ const processValue = (unsafe: string) => {
   }
 
   return escapeHtml(unsafe);
-};
+}
 
-const getDataFields = (fields: EntryFields) => fields.filter(f => !f!.get('meta')).toList();
+function getDataFields(fields: EntryFields) {
-const getMetaFields = (fields: EntryFields) => fields.filter(f => f!.get('meta') === true).toList();
+  return fields.filter(f => !f!.get('meta')).toList();
+}
+
+function getMetaFields(fields: EntryFields) {
+  return fields.filter(f => f!.get('meta') === true).toList();
+}
 
 export function createEmptyDraft(collection: Collection, search: string) {
   return async (dispatch: ThunkDispatch<State, {}, AnyAction>, getState: () => State) => {
@@ -785,7 +790,10 @@ export function createEmptyDraftData(
       const list = item.get('widget') == 'list';
       const name = item.get('name');
       const defaultValue = item.get('default', null);
-      const isEmptyDefaultValue = (val: unknown) => [[{}], {}].some(e => isEqual(val, e));
+
+      function isEmptyDefaultValue(val: unknown) {
+        return [[{}], {}].some(e => isEqual(val, e));
+      }
 
       if (List.isList(subfields)) {
         const subDefaultValue = list
@@ -831,9 +839,9 @@ function createEmptyDraftI18nData(collection: Collection, dataFields: EntryField
     return {};
   }
 
-  const skipField = (field: EntryField) => {
+  function skipField(field: EntryField) {
     return field.get(I18N) !== I18N_FIELD.DUPLICATE && field.get(I18N) !== I18N_FIELD.TRANSLATE;
-  };
+  }
 
   const i18nData = createEmptyDraftData(dataFields, true, skipField);
   return duplicateDefaultI18nFields(collection, i18nData);
@@ -850,23 +858,25 @@ export function getMediaAssets({ entry }: { entry: EntryMap }) {
   return assets;
 }
 
-export const getSerializedEntry = (collection: Collection, entry: Entry) => {
+export function getSerializedEntry(collection: Collection, entry: Entry) {
   /**
    * Serialize the values of any fields with registered serializers, and
    * update the entry and entryDraft with the serialized values.
    */
   const fields = selectFields(collection, entry.get('slug'));
+
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  const serializeData = (data: any) => {
+  function serializeData(data: any) {
     return serializeValues(data, fields);
-  };
+  }
+
   const serializedData = serializeData(entry.get('data'));
   let serializedEntry = entry.set('data', serializedData);
   if (hasI18n(collection)) {
     serializedEntry = serializeI18n(collection, serializedEntry, serializeData);
   }
   return serializedEntry;
-};
+}
 
 export function persistEntry(collection: Collection) {
   return async (dispatch: ThunkDispatch<State, {}, AnyAction>, getState: () => State) => {
@@ -982,11 +992,11 @@ export function deleteEntry(collection: Collection, slug: string) {
   };
 }
 
-const getPathError = (
+function getPathError(
   path: string | undefined,
   key: string,
   t: (key: string, args: Record<string, unknown>) => string,
-) => {
+) {
   return {
     error: {
       type: ValidationErrorTypes.CUSTOM,
@@ -995,7 +1005,7 @@ const getPathError = (
       }),
     },
   };
-};
+}
 
 export function validateMetaField(
   state: State,

packages/netlify-cms-core/src/actions/media.ts

@@ -82,10 +82,10 @@ export function boundGetAsset(
   collection: Collection,
   entry: EntryMap,
 ) {
-  const bound = (path: string, field: EntryField) => {
+  function bound(path: string, field: EntryField) {
     const asset = dispatch(getAsset({ collection, entry, path, field }));
     return asset;
-  };
+  }
 
   return bound;
 }

packages/netlify-cms-core/src/actions/mediaLibrary.ts

@@ -158,8 +158,8 @@ export function loadMedia(
     }
     dispatch(mediaLoading(page));
 
-    const loadFunction = () =>
+    function loadFunction() {
-      backend
+      return backend
         .getMedia()
         .then(files => dispatch(mediaLoaded(files)))
         .catch((error: { status?: number }) => {
@@ -171,6 +171,7 @@ export function loadMedia(
             dispatch(mediaLoadFailed());
           }
         });
+    }
 
     if (delay > 0) {
       return new Promise(resolve => {

packages/netlify-cms-core/src/actions/waitUntil.ts

@@ -3,19 +3,19 @@ import { ThunkDispatch } from 'redux-thunk';
 import { AnyAction } from 'redux';
 import { State } from '../types/redux';
 
-export const waitUntil = ({ predicate, run }: WaitActionArgs) => {
+export function waitUntil({ predicate, run }: WaitActionArgs) {
   return {
     type: WAIT_UNTIL_ACTION,
     predicate,
     run,
   };
-};
+}
 
-export const waitUntilWithTimeout = async <T>(
+export async function waitUntilWithTimeout<T>(
   dispatch: ThunkDispatch<State, {}, AnyAction>,
   waitActionArgs: (resolve: (value?: T) => void) => WaitActionArgs,
   timeout = 30000,
-): Promise<T | null> => {
+): Promise<T | null> {
   let waitDone = false;
 
   const waitPromise = new Promise<T>(resolve => {
@@ -44,4 +44,4 @@ export const waitUntilWithTimeout = async <T>(
   ]);
 
   return result;
-};
+}

packages/netlify-cms-core/src/backend.ts

@@ -71,13 +71,13 @@ import {
 
 const { extractTemplateVars, dateParsers, expandPath } = stringTemplate;
 
-const updateAssetProxies = (
+function updateAssetProxies(
   assetProxies: AssetProxy[],
   config: Config,
   collection: Collection,
   entryDraft: EntryDraft,
   path: string,
-) => {
+) {
   assetProxies.map(asset => {
     // update media files path based on entry path
     const oldPath = asset.path;
@@ -90,7 +90,7 @@ const updateAssetProxies = (
     );
     asset.path = newPath;
   });
-};
+}
 
 export class LocalStorageAuthStore {
   storageKey = 'netlify-cms-user';
@@ -118,7 +118,7 @@ function getEntryBackupKey(collectionName?: string, slug?: string) {
   return `${baseKey}.${collectionName}${suffix}`;
 }
 
-const getEntryField = (field: string, entry: EntryValue) => {
+function getEntryField(field: string, entry: EntryValue) {
   const value = get(entry.data, field);
   if (value) {
     return String(value);
@@ -131,9 +131,10 @@ const getEntryField = (field: string, entry: EntryValue) => {
       return '';
     }
   }
-};
+}
 
-export const extractSearchFields = (searchFields: string[]) => (entry: EntryValue) =>
+export function extractSearchFields(searchFields: string[]) {
+  return (entry: EntryValue) =>
     searchFields.reduce((acc, field) => {
       const value = getEntryField(field, entry);
       if (value) {
@@ -142,8 +143,9 @@ export const extractSearchFields = (searchFields: string[]) => (entry: EntryValu
         return acc;
       }
     }, '');
+}
 
-export const expandSearchEntries = (entries: EntryValue[], searchFields: string[]) => {
+export function expandSearchEntries(entries: EntryValue[], searchFields: string[]) {
   // expand the entries for the purpose of the search
   const expandedEntries = entries.reduce((acc, e) => {
     const expandedFields = searchFields.reduce((acc, f) => {
@@ -160,9 +162,9 @@ export const expandSearchEntries = (entries: EntryValue[], searchFields: string[
   }, [] as (EntryValue & { field: string })[]);
 
   return expandedEntries;
-};
+}
 
-export const mergeExpandedEntries = (entries: (EntryValue & { field: string })[]) => {
+export function mergeExpandedEntries(entries: (EntryValue & { field: string })[]) {
   // merge the search results by slug and only keep data that matched the search
   const fields = entries.map(f => f.field);
   const arrayPaths: Record<string, Set<string>> = {};
@@ -214,20 +216,20 @@ export const mergeExpandedEntries = (entries: (EntryValue & { field: string })[]
   });
 
   return Object.values(merged);
-};
+}
 
-const sortByScore = (a: fuzzy.FilterResult<EntryValue>, b: fuzzy.FilterResult<EntryValue>) => {
+function sortByScore(a: fuzzy.FilterResult<EntryValue>, b: fuzzy.FilterResult<EntryValue>) {
   if (a.score > b.score) return -1;
   if (a.score < b.score) return 1;
   return 0;
-};
+}
 
-export const slugFromCustomPath = (collection: Collection, customPath: string) => {
+export function slugFromCustomPath(collection: Collection, customPath: string) {
   const folderPath = collection.get('folder', '') as string;
   const entryPath = customPath.toLowerCase().replace(folderPath.toLowerCase(), '');
   const slug = join(dirname(trim(entryPath, '/')), basename(entryPath, extname(customPath)));
   return slug;
-};
+}
 
 interface AuthStore {
   retrieve: () => User;
@@ -280,15 +282,15 @@ type Implementation = BackendImplementation & {
   init: (config: ImplementationConfig, options: ImplementationInitOptions) => Implementation;
 };
 
-const prepareMetaPath = (path: string, collection: Collection) => {
+function prepareMetaPath(path: string, collection: Collection) {
   if (!selectHasMetaPath(collection)) {
     return path;
   }
   const dir = dirname(path);
   return dir.substr(collection.get('folder')!.length + 1) || '/';
-};
+}
 
-const collectionDepth = (collection: Collection) => {
+function collectionDepth(collection: Collection) {
   let depth;
   depth =
     collection.get('nested')?.get('depth') || getPathDepth(collection.get('path', '') as string);
@@ -298,7 +300,7 @@ const collectionDepth = (collection: Collection) => {
   }
 
   return depth;
-};
+}
 
 export class Backend {
   implementation: Implementation;

packages/netlify-cms-core/src/bootstrap.js

@@ -19,7 +19,7 @@ import 'what-input';
 
 const ROOT_ID = 'nc-root';
 
-const TranslatedApp = ({ locale, config }) => {
+function TranslatedApp({ locale, config }) {
   return (
     <I18n locale={locale} messages={getPhrases(locale)}>
       <ErrorBoundary showBackup config={config}>
@@ -29,11 +29,11 @@ const TranslatedApp = ({ locale, config }) => {
       </ErrorBoundary>
     </I18n>
   );
-};
+}
 
-const mapDispatchToProps = state => {
+function mapDispatchToProps(state) {
   return { locale: selectLocale(state.config), config: state.config };
-};
+}
 
 const ConnectedTranslatedApp = connect(mapDispatchToProps)(TranslatedApp);
 
@@ -82,7 +82,8 @@ function bootstrap(opts = {}) {
   /**
    * Create connected root component.
    */
-  const Root = () => (
+  function Root() {
+    return (
       <>
         <GlobalStyles />
         <Provider store={store}>
@@ -90,6 +91,7 @@ function bootstrap(opts = {}) {
         </Provider>
       </>
     );
+  }
 
   /**
    * Render application root.

packages/netlify-cms-core/src/components/App/App.js

@@ -48,16 +48,16 @@ const ErrorCodeBlock = styled.pre`
   line-height: 1.5;
 `;
 
-const getDefaultPath = collections => {
+function getDefaultPath(collections) {
   const first = collections.filter(collection => collection.get('hide') !== true).first();
   if (first) {
     return `/collections/${first.get('name')}`;
   } else {
     throw new Error('Could not find a non hidden collection');
   }
-};
+}
 
-const RouteInCollection = ({ collections, render, ...props }) => {
+function RouteInCollection({ collections, render, ...props }) {
   const defaultPath = getDefaultPath(collections);
   return (
     <Route
@@ -68,7 +68,7 @@ const RouteInCollection = ({ collections, render, ...props }) => {
       }}
     />
   );
-};
+}
 
 class App extends React.Component {
   static propTypes = {

packages/netlify-cms-core/src/components/App/Header.js

@@ -26,7 +26,8 @@ const styles = {
   `,
 };
 
-const AppHeader = props => (
+function AppHeader(props) {
+  return (
     <header
       css={css`
         ${shadows.dropMain};
@@ -39,7 +40,8 @@ const AppHeader = props => (
       `}
       {...props}
     />
-);
+  );
+}
 
 const AppHeaderContent = styled.div`
   display: flex;

packages/netlify-cms-core/src/components/App/NotFoundPage.js

@@ -8,11 +8,13 @@ const NotFoundContainer = styled.div`
   margin: ${lengths.pageMargin};
 `;
 
-const NotFoundPage = ({ t }) => (
+function NotFoundPage({ t }) {
+  return (
     <NotFoundContainer>
       <h2>{t('app.notFoundPage.header')}</h2>
     </NotFoundContainer>
-);
+  );
+}
 
 NotFoundPage.propTypes = {
   t: PropTypes.func.isRequired,

packages/netlify-cms-core/src/components/Collection/Collection.js

@@ -183,7 +183,7 @@ const mapDispatchToProps = {
   groupByField,
 };
 
-const mergeProps = (stateProps, dispatchProps, ownProps) => {
+function mergeProps(stateProps, dispatchProps, ownProps) {
   return {
     ...stateProps,
     ...ownProps,
@@ -193,7 +193,7 @@ const mergeProps = (stateProps, dispatchProps, ownProps) => {
     onGroupClick: group => dispatchProps.groupByField(stateProps.collection, group),
     onChangeViewStyle: viewStyle => dispatchProps.changeViewStyle(viewStyle),
   };
-};
+}
 
 const ConnectedCollection = connect(mapStateToProps, mapDispatchToProps, mergeProps)(Collection);
 

packages/netlify-cms-core/src/components/Collection/CollectionControls.js

@@ -19,7 +19,7 @@ const CollectionControlsContainer = styled.div`
   }
 `;
 
-const CollectionControls = ({
+function CollectionControls({
   viewStyle,
   onChangeViewStyle,
   sortableFields,
@@ -32,7 +32,7 @@ const CollectionControls = ({
   t,
   filter,
   group,
-}) => {
+}) {
   return (
     <CollectionControlsContainer>
       <ViewStyleControl viewStyle={viewStyle} onChangeViewStyle={onChangeViewStyle} />
@@ -52,6 +52,6 @@ const CollectionControls = ({
       )}
     </CollectionControlsContainer>
   );
-};
+}
 
 export default CollectionControls;

packages/netlify-cms-core/src/components/Collection/CollectionTop.js

@@ -35,7 +35,7 @@ const CollectionTopDescription = styled.p`
   margin-bottom: 0;
 `;
 
-const getCollectionProps = collection => {
+function getCollectionProps(collection) {
   const collectionLabel = collection.get('label');
   const collectionLabelSingular = collection.get('label_singular');
   const collectionDescription = collection.get('description');
@@ -45,9 +45,9 @@ const getCollectionProps = collection => {
     collectionLabelSingular,
     collectionDescription,
   };
-};
+}
 
-const CollectionTop = ({ collection, newEntryUrl, t }) => {
+function CollectionTop({ collection, newEntryUrl, t }) {
   const { collectionLabel, collectionLabelSingular, collectionDescription } = getCollectionProps(
     collection,
     t,
@@ -70,7 +70,7 @@ const CollectionTop = ({ collection, newEntryUrl, t }) => {
       ) : null}
     </CollectionTopContainer>
   );
-};
+}
 
 CollectionTop.propTypes = {
   collection: ImmutablePropTypes.map.isRequired,

packages/netlify-cms-core/src/components/Collection/ControlButton.js

@@ -14,7 +14,7 @@ const Button = styled(StyledDropdownButton)`
   }
 `;
 
-export const ControlButton = ({ active, title }) => {
+export function ControlButton({ active, title }) {
   return (
     <Button
       css={css`
@@ -24,4 +24,4 @@ export const ControlButton = ({ active, title }) => {
       {title}
     </Button>
   );
-};
+}

packages/netlify-cms-core/src/components/Collection/Entries/Entries.js

@@ -16,7 +16,7 @@ const NoEntriesMessage = styled(PaginationMessage)`
   margin-top: 16px;
 `;
 
-const Entries = ({
+function Entries({
   collections,
   entries,
   isFetching,
@@ -25,7 +25,7 @@ const Entries = ({
   handleCursorActions,
   t,
   page,
-}) => {
+}) {
   const loadingMessages = [
     t('collection.entries.loadingEntries'),
     t('collection.entries.cachingEntries'),
@@ -56,7 +56,7 @@ const Entries = ({
   }
 
   return <NoEntriesMessage>{t('collection.entries.noEntries')}</NoEntriesMessage>;
-};
+}
 
 Entries.propTypes = {
   collections: ImmutablePropTypes.iterable.isRequired,

packages/netlify-cms-core/src/components/Collection/Entries/EntriesCollection.js

@@ -28,11 +28,11 @@ const GroupHeading = styled.h2`
 
 const GroupContainer = styled.div``;
 
-const getGroupEntries = (entries, paths) => {
+function getGroupEntries(entries, paths) {
   return entries.filter(entry => paths.has(entry.get('path')));
-};
+}
 
-const getGroupTitle = (group, t) => {
+function getGroupTitle(group, t) {
   const { label, value } = group;
   if (value === undefined) {
     return t('collection.groups.other');
@@ -41,9 +41,9 @@ const getGroupTitle = (group, t) => {
     return value ? label : t('collection.groups.negateLabel', { label });
   }
   return `${label} ${value}`.trim();
-};
+}
 
-const withGroups = (groups, entries, EntriesToRender, t) => {
+function withGroups(groups, entries, EntriesToRender, t) {
   return groups.map(group => {
     const title = getGroupTitle(group, t);
     return (
@@ -53,7 +53,7 @@ const withGroups = (groups, entries, EntriesToRender, t) => {
       </GroupContainer>
     );
   });
-};
+}
 
 export class EntriesCollection extends React.Component {
   static propTypes = {
@@ -114,7 +114,7 @@ export class EntriesCollection extends React.Component {
   }
 }
 
-export const filterNestedEntries = (path, collectionFolder, entries) => {
+export function filterNestedEntries(path, collectionFolder, entries) {
   const filtered = entries.filter(e => {
     const entryPath = e.get('path').substring(collectionFolder.length + 1);
     if (!entryPath.startsWith(path)) {
@@ -132,7 +132,7 @@ export const filterNestedEntries = (path, collectionFolder, entries) => {
     }
   });
   return filtered;
-};
+}
 
 function mapStateToProps(state, ownProps) {
   const { collection, viewStyle, filterTerm } = ownProps;

packages/netlify-cms-core/src/components/Collection/Entries/EntryCard.js

@@ -84,7 +84,7 @@ const CardImage = styled.div`
   height: 150px;
 `;
 
-const EntryCard = ({
+function EntryCard({
   path,
   summary,
   image,
@@ -92,7 +92,7 @@ const EntryCard = ({
   collectionLabel,
   viewStyle = VIEW_STYLE_LIST,
   getAsset,
-}) => {
+}) {
   if (viewStyle === VIEW_STYLE_LIST) {
     return (
       <ListCard>
@@ -117,9 +117,9 @@ const EntryCard = ({
       </GridCard>
     );
   }
-};
+}
 
-const mapStateToProps = (state, ownProps) => {
+function mapStateToProps(state, ownProps) {
   const { entry, inferedFields, collection } = ownProps;
   const entryData = entry.get('data');
   const summary = selectEntryCollectionTitle(collection, entry);
@@ -140,22 +140,22 @@ const mapStateToProps = (state, ownProps) => {
       ?.find(f => f.get('name') === inferedFields.imageField && f.get('widget') === 'image'),
     isLoadingAsset,
   };
-};
+}
 
-const mapDispatchToProps = dispatch => {
+function mapDispatchToProps(dispatch) {
   return {
     boundGetAsset: (collection, entry) => boundGetAsset(dispatch, collection, entry),
   };
-};
+}
 
-const mergeProps = (stateProps, dispatchProps, ownProps) => {
+function mergeProps(stateProps, dispatchProps, ownProps) {
   return {
     ...stateProps,
     ...dispatchProps,
     ...ownProps,
     getAsset: dispatchProps.boundGetAsset(ownProps.collection, ownProps.entry),
   };
-};
+}
 
 const ConnectedEntryCard = connect(mapStateToProps, mapDispatchToProps, mergeProps)(EntryCard);
 

packages/netlify-cms-core/src/components/Collection/Entries/__tests__/EntriesCollection.spec.js

@@ -13,14 +13,15 @@ jest.mock('../Entries', () => 'mock-entries');
 const middlewares = [];
 const mockStore = configureStore(middlewares);
 
-const renderWithRedux = (component, { store } = {}) => {
+function renderWithRedux(component, { store } = {}) {
   function Wrapper({ children }) {
     return <Provider store={store}>{children}</Provider>;
   }
-  return render(component, { wrapper: Wrapper });
-};
 
-const toEntriesState = (collection, entriesArray) => {
+  return render(component, { wrapper: Wrapper });
+}
+
+function toEntriesState(collection, entriesArray) {
   const entries = entriesArray.reduce(
     (acc, entry) => {
       acc.entities[`${collection.get('name')}.${entry.slug}`] = entry;
@@ -30,7 +31,7 @@ const toEntriesState = (collection, entriesArray) => {
     { pages: { [collection.get('name')]: { ids: [] } }, entities: {} },
   );
   return fromJS(entries);
-};
+}
 
 describe('filterNestedEntries', () => {
   it('should return only immediate children for non root path', () => {

packages/netlify-cms-core/src/components/Collection/FilterControl.js

@@ -3,7 +3,7 @@ import { translate } from 'react-polyglot';
 import { Dropdown, DropdownCheckedItem } from 'netlify-cms-ui-default';
 import { ControlButton } from './ControlButton';
 
-const FilterControl = ({ viewFilters, t, onFilterClick, filter }) => {
+function FilterControl({ viewFilters, t, onFilterClick, filter }) {
   const hasActiveFilter = filter
     ?.valueSeq()
     .toJS()
@@ -33,6 +33,6 @@ const FilterControl = ({ viewFilters, t, onFilterClick, filter }) => {
       })}
     </Dropdown>
   );
-};
+}
 
 export default translate()(FilterControl);

packages/netlify-cms-core/src/components/Collection/GroupControl.js

@@ -3,7 +3,7 @@ import { translate } from 'react-polyglot';
 import { Dropdown, DropdownItem } from 'netlify-cms-ui-default';
 import { ControlButton } from './ControlButton';
 
-const GroupControl = ({ viewGroups, t, onGroupClick, group }) => {
+function GroupControl({ viewGroups, t, onGroupClick, group }) {
   const hasActiveGroup = group
     ?.valueSeq()
     .toJS()
@@ -33,6 +33,6 @@ const GroupControl = ({ viewGroups, t, onGroupClick, group }) => {
       })}
     </Dropdown>
   );
-};
+}
 
 export default translate()(GroupControl);

packages/netlify-cms-core/src/components/Collection/NestedCollection.js

@@ -66,14 +66,14 @@ const TreeNavLink = styled(NavLink)`
   `};
 `;
 
-const getNodeTitle = node => {
+function getNodeTitle(node) {
   const title = node.isRoot
     ? node.title
     : node.children.find(c => !c.isDir && c.title)?.title || node.title;
   return title;
-};
+}
 
-const TreeNode = props => {
+function TreeNode(props) {
   const { collection, treeData, depth = 0, onToggle } = props;
   const collectionName = collection.get('name');
 
@@ -118,7 +118,7 @@ const TreeNode = props => {
       </React.Fragment>
     );
   });
-};
+}
 
 TreeNode.propTypes = {
   collection: ImmutablePropTypes.map.isRequired,
@@ -127,18 +127,18 @@ TreeNode.propTypes = {
   onToggle: PropTypes.func.isRequired,
 };
 
-export const walk = (treeData, callback) => {
+export function walk(treeData, callback) {
-  const traverse = children => {
+  function traverse(children) {
     for (const child of children) {
       callback(child);
       traverse(child.children);
     }
-  };
+  }
 
   return traverse(treeData);
-};
+}
 
-export const getTreeData = (collection, entries) => {
+export function getTreeData(collection, entries) {
   const collectionFolder = collection.get('folder');
   const rootFolder = '/';
   const entriesObj = entries
@@ -200,7 +200,7 @@ export const getTreeData = (collection, entries) => {
     return acc;
   }, {});
 
-  const reducer = (acc, value) => {
+  function reducer(acc, value) {
     const node = value;
     let children = [];
     if (parentsToChildren[node.path]) {
@@ -209,17 +209,17 @@ export const getTreeData = (collection, entries) => {
 
     acc.push({ ...node, children });
     return acc;
-  };
+  }
 
   const treeData = parentsToChildren[''].reduce(reducer, []);
 
   return treeData;
-};
+}
 
-export const updateNode = (treeData, node, callback) => {
+export function updateNode(treeData, node, callback) {
   let stop = false;
 
-  const updater = nodes => {
+  function updater(nodes) {
     if (stop) {
       return nodes;
     }
@@ -232,10 +232,10 @@ export const updateNode = (treeData, node, callback) => {
     }
     nodes.forEach(node => updater(node.children));
     return nodes;
-  };
+  }
 
   return updater([...treeData]);
-};
+}
 
 export class NestedCollection extends React.Component {
   static propTypes = {

packages/netlify-cms-core/src/components/Collection/SortControl.js

@@ -28,7 +28,7 @@ const sortIconDirections = {
   [SortDirection.Descending]: 'down',
 };
 
-const SortControl = ({ t, fields, onSortClick, sort }) => {
+function SortControl({ t, fields, onSortClick, sort }) {
   const hasActiveSort = sort
     ?.valueSeq()
     .toJS()
@@ -62,6 +62,6 @@ const SortControl = ({ t, fields, onSortClick, sort }) => {
       })}
     </Dropdown>
   );
-};
+}
 
 export default translate()(SortControl);

packages/netlify-cms-core/src/components/Collection/ViewStyleControl.js

@@ -27,7 +27,7 @@ const ViewControlsButton = styled.button`
   }
 `;
 
-const ViewStyleControl = ({ viewStyle, onChangeViewStyle }) => {
+function ViewStyleControl({ viewStyle, onChangeViewStyle }) {
   return (
     <ViewControlsSection>
       <ViewControlsButton
@@ -44,6 +44,6 @@ const ViewStyleControl = ({ viewStyle, onChangeViewStyle }) => {
       </ViewControlsButton>
     </ViewControlsSection>
   );
-};
+}
 
 export default ViewStyleControl;

packages/netlify-cms-core/src/components/Collection/__tests__/Collection.spec.js

@@ -13,12 +13,13 @@ jest.mock('../Sidebar', () => 'mock-sidebar');
 const middlewares = [];
 const mockStore = configureStore(middlewares);
 
-const renderWithRedux = (component, { store } = {}) => {
+function renderWithRedux(component, { store } = {}) {
   function Wrapper({ children }) {
     return <Provider store={store}>{children}</Provider>;
   }
+
   return render(component, { wrapper: Wrapper });
-};
+}
 
 describe('Collection', () => {
   const collection = fromJS({

packages/netlify-cms-core/src/components/Collection/__tests__/NestedCollection.spec.js

@@ -22,12 +22,13 @@ jest.mock('netlify-cms-ui-default', () => {
 const middlewares = [];
 const mockStore = configureStore(middlewares);
 
-const renderWithRedux = (component, { store } = {}) => {
+function renderWithRedux(component, { store } = {}) {
   function Wrapper({ children }) {
     return <Provider store={store}>{children}</Provider>;
   }
+
   return render(component, { wrapper: Wrapper });
-};
+}
 
 describe('NestedCollection', () => {
   const collection = fromJS({

packages/netlify-cms-core/src/components/Editor/EditorControlPane/EditorControl.js

@@ -95,7 +95,7 @@ export const ControlHint = styled.p`
   transition: color ${transitions.main};
 `;
 
-const LabelComponent = ({ field, isActive, hasErrors, uniqueFieldId, isFieldOptional, t }) => {
+function LabelComponent({ field, isActive, hasErrors, uniqueFieldId, isFieldOptional, t }) {
   const label = `${field.get('label', field.get('name'))}`;
   const labelComponent = (
     <FieldLabel isActive={isActive} hasErrors={hasErrors} htmlFor={uniqueFieldId}>
@@ -104,7 +104,7 @@ const LabelComponent = ({ field, isActive, hasErrors, uniqueFieldId, isFieldOpti
   );
 
   return labelComponent;
-};
+}
 
 class EditorControl extends React.Component {
   static propTypes = {
@@ -334,13 +334,13 @@ class EditorControl extends React.Component {
   }
 }
 
-const mapStateToProps = state => {
+function mapStateToProps(state) {
   const { collections, entryDraft } = state;
   const entry = entryDraft.get('entry');
   const collection = collections.get(entryDraft.getIn(['entry', 'collection']));
   const isLoadingAsset = selectIsLoadingAsset(state.medias);
 
-  const loadEntry = async (collectionName, slug) => {
+  async function loadEntry(collectionName, slug) {
     const targetCollection = collections.get(collectionName);
     if (targetCollection) {
       const loadedEntry = await tryLoadEntry(state, targetCollection, slug);
@@ -348,7 +348,7 @@ const mapStateToProps = state => {
     } else {
       throw new Error(`Can't find collection '${collectionName}'`);
     }
-  };
+  }
 
   return {
     mediaPaths: state.mediaLibrary.get('controlMedia'),
@@ -361,9 +361,9 @@ const mapStateToProps = state => {
     loadEntry,
     validateMetaField: (field, value, t) => validateMetaField(state, collection, field, value, t),
   };
-};
+}
 
-const mapDispatchToProps = dispatch => {
+function mapDispatchToProps(dispatch) {
   const creators = bindActionCreators(
     {
       openMediaLibrary,
@@ -381,16 +381,16 @@ const mapDispatchToProps = dispatch => {
     ...creators,
     boundGetAsset: (collection, entry) => boundGetAsset(dispatch, collection, entry),
   };
-};
+}
 
-const mergeProps = (stateProps, dispatchProps, ownProps) => {
+function mergeProps(stateProps, dispatchProps, ownProps) {
   return {
     ...stateProps,
     ...dispatchProps,
     ...ownProps,
     boundGetAsset: dispatchProps.boundGetAsset(stateProps.collection, stateProps.entry),
   };
-};
+}
 
 const ConnectedEditorControl = connect(
   mapStateToProps,

packages/netlify-cms-core/src/components/Editor/EditorControlPane/EditorControlPane.js

@@ -50,7 +50,7 @@ const StyledDropdown = styled(Dropdown)`
   margin-bottom: 20px;
 `;
 
-const LocaleDropdown = ({ locales, selectedLocale, onLocaleChange, t }) => {
+function LocaleDropdown({ locales, selectedLocale, onLocaleChange, t }) {
   return (
     <StyledDropdown
       renderButton={() => {
@@ -77,9 +77,9 @@ const LocaleDropdown = ({ locales, selectedLocale, onLocaleChange, t }) => {
       ))}
     </StyledDropdown>
   );
-};
+}
 
-const getFieldValue = ({ field, entry, isTranslatable, locale }) => {
+function getFieldValue({ field, entry, isTranslatable, locale }) {
   if (field.get('meta')) {
     return entry.getIn(['meta', field.get('name')]);
   }
@@ -90,7 +90,7 @@ const getFieldValue = ({ field, entry, isTranslatable, locale }) => {
   }
 
   return entry.getIn(['data', field.get('name')]);
-};
+}
 
 export default class ControlPane extends React.Component {
   state = {

packages/netlify-cms-core/src/components/Editor/EditorControlPane/Widget.js

@@ -5,14 +5,19 @@ import { Map, List } from 'immutable';
 import { oneLine } from 'common-tags';
 import ValidationErrorTypes from 'Constants/validationErrorTypes';
 
-const truthy = () => ({ error: false });
+function truthy() {
+  return { error: false };
+}
 
-const isEmpty = value =>
+function isEmpty(value) {
+  return (
     value === null ||
     value === undefined ||
     (Object.prototype.hasOwnProperty.call(value, 'length') && value.length === 0) ||
     (value.constructor === Object && Object.keys(value).length === 0) ||
-  (List.isList(value) && value.size === 0);
+    (List.isList(value) && value.size === 0)
+  );
+}
 
 export default class Widget extends Component {
   static propTypes = {

packages/netlify-cms-core/src/components/Editor/EditorInterface.js

@@ -41,7 +41,8 @@ const EditorToggle = styled(IconButton)`
   margin-bottom: 12px;
 `;
 
-const ReactSplitPaneGlobalStyles = () => (
+function ReactSplitPaneGlobalStyles() {
+  return (
     <Global
       styles={css`
         .Resizer.vertical {
@@ -67,7 +68,8 @@ const ReactSplitPaneGlobalStyles = () => (
         }
       `}
     />
-);
+  );
+}
 
 const StyledSplitPane = styled(SplitPane)`
   ${styles.splitPane};
@@ -121,13 +123,13 @@ const ViewControls = styled.div`
   z-index: ${zIndex.zIndex299};
 `;
 
-const EditorContent = ({
+function EditorContent({
   i18nVisible,
   previewVisible,
   editor,
   editorWithEditor,
   editorWithPreview,
-}) => {
+}) {
   if (i18nVisible) {
     return editorWithEditor;
   } else if (previewVisible) {
@@ -135,7 +137,7 @@ const EditorContent = ({
   } else {
     return <NoPreviewContainer>{editor}</NoPreviewContainer>;
   }
-};
+}
 
 function isPreviewEnabled(collection, entry) {
   if (collection.get('type') === FILES) {

packages/netlify-cms-core/src/components/Editor/EditorPreviewPane/EditorPreviewPane.js

@@ -248,24 +248,24 @@ PreviewPane.propTypes = {
   getAsset: PropTypes.func.isRequired,
 };
 
-const mapStateToProps = state => {
+function mapStateToProps(state) {
   const isLoadingAsset = selectIsLoadingAsset(state.medias);
   return { isLoadingAsset, config: state.config };
-};
+}
 
-const mapDispatchToProps = dispatch => {
+function mapDispatchToProps(dispatch) {
   return {
     boundGetAsset: (collection, entry) => boundGetAsset(dispatch, collection, entry),
   };
-};
+}
 
-const mergeProps = (stateProps, dispatchProps, ownProps) => {
+function mergeProps(stateProps, dispatchProps, ownProps) {
   return {
     ...stateProps,
     ...dispatchProps,
     ...ownProps,
     getAsset: dispatchProps.boundGetAsset(ownProps.collection, ownProps.entry),
   };
-};
+}
 
 export default connect(mapStateToProps, mapDispatchToProps, mergeProps)(PreviewPane);

packages/netlify-cms-core/src/components/EditorWidgets/Unknown/UnknownControl.js

@@ -3,11 +3,11 @@ import { translate } from 'react-polyglot';
 import ImmutablePropTypes from 'react-immutable-proptypes';
 import PropTypes from 'prop-types';
 
-const UnknownControl = ({ field, t }) => {
+function UnknownControl({ field, t }) {
   return (
     <div>{t('editor.editorWidgets.unknownControl.noControl', { widget: field.get('widget') })}</div>
   );
-};
+}
 
 UnknownControl.propTypes = {
   field: ImmutablePropTypes.map,

packages/netlify-cms-core/src/components/EditorWidgets/Unknown/UnknownPreview.js

@@ -3,13 +3,13 @@ import { translate } from 'react-polyglot';
 import ImmutablePropTypes from 'react-immutable-proptypes';
 import PropTypes from 'prop-types';
 
-const UnknownPreview = ({ field, t }) => {
+function UnknownPreview({ field, t }) {
   return (
     <div className="nc-widgetPreview">
       {t('editor.editorWidgets.unknownPreview.noPreview', { widget: field.get('widget') })}
     </div>
   );
-};
+}
 
 UnknownPreview.propTypes = {
   field: ImmutablePropTypes.map,

packages/netlify-cms-core/src/components/MediaLibrary/EmptyMessage.js

@@ -12,11 +12,13 @@ const EmptyMessageContainer = styled.div`
   color: ${props => props.isPrivate && colors.textFieldBorder};
 `;
 
-const EmptyMessage = ({ content, isPrivate }) => (
+function EmptyMessage({ content, isPrivate }) {
+  return (
     <EmptyMessageContainer isPrivate={isPrivate}>
       <h1>{content}</h1>
     </EmptyMessageContainer>
-);
+  );
+}
 
 EmptyMessage.propTypes = {
   content: PropTypes.string.isRequired,

packages/netlify-cms-core/src/components/MediaLibrary/MediaLibrary.js

@@ -354,7 +354,7 @@ class MediaLibrary extends React.Component {
   }
 }
 
-const mapStateToProps = state => {
+function mapStateToProps(state) {
   const { mediaLibrary } = state;
   const field = mediaLibrary.get('field');
   const mediaLibraryProps = {
@@ -377,7 +377,7 @@ const mapStateToProps = state => {
     field,
   };
   return { ...mediaLibraryProps };
-};
+}
 
 const mapDispatchToProps = {
   loadMedia: loadMediaAction,

packages/netlify-cms-core/src/components/MediaLibrary/MediaLibraryCardGrid.js

@@ -8,7 +8,7 @@ import { colors } from 'netlify-cms-ui-default';
 import { FixedSizeGrid as Grid } from 'react-window';
 import AutoSizer from 'react-virtualized-auto-sizer';
 
-const CardWrapper = props => {
+function CardWrapper(props) {
   const {
     rowIndex,
     columnIndex,
@@ -61,9 +61,9 @@ const CardWrapper = props => {
       />
     </div>
   );
-};
+}
 
-const VirtualizedGrid = props => {
+function VirtualizedGrid(props) {
   const { mediaItems, setScrollContainerRef } = props;
 
   return (
@@ -94,9 +94,9 @@ const VirtualizedGrid = props => {
       </AutoSizer>
     </CardGridContainer>
   );
-};
+}
 
-const PaginatedGrid = ({
+function PaginatedGrid({
   setScrollContainerRef,
   mediaItems,
   isSelectedFile,
@@ -112,7 +112,7 @@ const PaginatedGrid = ({
   onLoadMore,
   isPaginating,
   paginatingMessage,
-}) => {
+}) {
   return (
     <CardGridContainer ref={setScrollContainerRef}>
       <CardGrid>
@@ -141,7 +141,7 @@ const PaginatedGrid = ({
       )}
     </CardGridContainer>
   );
-};
+}
 
 const CardGridContainer = styled.div`
   overflow-y: auto;
@@ -160,13 +160,13 @@ const PaginatingMessage = styled.h1`
   color: ${props => props.isPrivate && colors.textFieldBorder};
 `;
 
-const MediaLibraryCardGrid = props => {
+function MediaLibraryCardGrid(props) {
   const { canLoadMore, isPaginating } = props;
   if (canLoadMore || isPaginating) {
     return <PaginatedGrid {...props} />;
   }
   return <VirtualizedGrid {...props} />;
-};
+}
 
 MediaLibraryCardGrid.propTypes = {
   setScrollContainerRef: PropTypes.func.isRequired,

packages/netlify-cms-core/src/components/MediaLibrary/MediaLibraryHeader.js

@@ -28,14 +28,16 @@ const LibraryTitle = styled.h1`
   color: ${props => props.isPrivate && colors.textFieldBorder};
 `;
 
-const MediaLibraryHeader = ({ onClose, title, isPrivate }) => (
+function MediaLibraryHeader({ onClose, title, isPrivate }) {
+  return (
     <div>
       <CloseButton onClick={onClose}>
         <Icon type="close" />
       </CloseButton>
       <LibraryTitle isPrivate={isPrivate}>{title}</LibraryTitle>
     </div>
-);
+  );
+}
 
 MediaLibraryHeader.propTypes = {
   onClose: PropTypes.func.isRequired,

packages/netlify-cms-core/src/components/MediaLibrary/MediaLibraryModal.js

@@ -60,7 +60,7 @@ const StyledModal = styled(Modal)`
   }
 `;
 
-const MediaLibraryModal = ({
+function MediaLibraryModal({
   isVisible,
   canInsert,
   files,
@@ -91,7 +91,7 @@ const MediaLibraryModal = ({
   loadDisplayURL,
   displayURLs,
   t,
-}) => {
+}) {
   const filteredFiles = forImage ? handleFilter(files) : files;
   const queriedFiles = !dynamicSearch && query ? handleQuery(query, filteredFiles) : filteredFiles;
   const tableData = toTableData(queriedFiles);
@@ -152,7 +152,7 @@ const MediaLibraryModal = ({
       />
     </StyledModal>
   );
-};
+}
 
 export const fileShape = {
   displayURL: PropTypes.oneOfType([PropTypes.string, PropTypes.object]).isRequired,

packages/netlify-cms-core/src/components/MediaLibrary/MediaLibrarySearch.js

@@ -35,7 +35,8 @@ const SearchIcon = styled(Icon)`
   transform: translate(0, -50%);
 `;
 
-const MediaLibrarySearch = ({ value, onChange, onKeyDown, placeholder, disabled }) => (
+function MediaLibrarySearch({ value, onChange, onKeyDown, placeholder, disabled }) {
+  return (
     <SearchContainer>
       <SearchIcon type="search" size="small" />
       <SearchInput
@@ -46,7 +47,8 @@ const MediaLibrarySearch = ({ value, onChange, onKeyDown, placeholder, disabled
         disabled={disabled}
       />
     </SearchContainer>
-);
+  );
+}
 
 MediaLibrarySearch.propTypes = {
   value: PropTypes.string,

packages/netlify-cms-core/src/components/MediaLibrary/MediaLibraryTop.js

@@ -26,7 +26,7 @@ const ButtonsContainer = styled.div`
   flex-shrink: 0;
 `;
 
-const MediaLibraryTop = ({
+function MediaLibraryTop({
   t,
   onClose,
   privateUpload,
@@ -44,7 +44,7 @@ const MediaLibraryTop = ({
   isPersisting,
   isDeleting,
   selectedFile,
-}) => {
+}) {
   const shouldShowButtonLoader = isPersisting || isDeleting;
   const uploadEnabled = !shouldShowButtonLoader;
   const deleteEnabled = !shouldShowButtonLoader && hasSelection;
@@ -110,7 +110,7 @@ const MediaLibraryTop = ({
       </RowContainer>
     </LibraryTop>
   );
-};
+}
 
 MediaLibraryTop.propTypes = {
   t: PropTypes.func.isRequired,

packages/netlify-cms-core/src/components/UI/DragDrop.js

@@ -7,7 +7,7 @@ import {
 import React from 'react';
 import PropTypes from 'prop-types';
 
-export const DragSource = ({ namespace, ...props }) => {
+export function DragSource({ namespace, ...props }) {
   const DragComponent = ReactDNDDragSource(
     namespace,
     {
@@ -23,13 +23,14 @@ export const DragSource = ({ namespace, ...props }) => {
   )(({ children, connectDragComponent }) => children(connectDragComponent));
 
   return React.createElement(DragComponent, props, props.children);
-};
+}
+
 DragSource.propTypes = {
   namespace: PropTypes.any.isRequired,
   children: PropTypes.func.isRequired,
 };
 
-export const DropTarget = ({ onDrop, namespace, ...props }) => {
+export function DropTarget({ onDrop, namespace, ...props }) {
   const DropComponent = ReactDNDDropTarget(
     namespace,
     {
@@ -44,11 +45,14 @@ export const DropTarget = ({ onDrop, namespace, ...props }) => {
   )(({ children, connectDropTarget, isHovered }) => children(connectDropTarget, { isHovered }));
 
   return React.createElement(DropComponent, props, props.children);
-};
+}
+
 DropTarget.propTypes = {
   onDrop: PropTypes.func.isRequired,
   namespace: PropTypes.any.isRequired,
   children: PropTypes.func.isRequired,
 };
 
-export const HTML5DragDrop = component => ReactDNDDragDropContext(ReactDNDHTML5Backend)(component);
+export function HTML5DragDrop(component) {
+  return ReactDNDDragDropContext(ReactDNDHTML5Backend)(component);
+}

packages/netlify-cms-core/src/components/UI/ErrorBoundary.js

@@ -10,7 +10,9 @@ import { localForage } from 'netlify-cms-lib-util';
 import { buttons, colors } from 'netlify-cms-ui-default';
 
 const ISSUE_URL = 'https://github.com/netlify/netlify-cms/issues/new?';
-const getIssueTemplate = ({ version, provider, browser, config }) => `
+
+function getIssueTemplate({ version, provider, browser, config }) {
+  return `
 **Describe the bug**
 
 **To Reproduce**
@@ -31,8 +33,9 @@ ${config}
 
 **Additional context**
 `;
+}
 
-const buildIssueTemplate = ({ config }) => {
+function buildIssueTemplate({ config }) {
   let version = '';
   if (typeof NETLIFY_CMS_VERSION === 'string') {
     version = `netlify-cms@${NETLIFY_CMS_VERSION}`;
@@ -47,9 +50,9 @@ const buildIssueTemplate = ({ config }) => {
   });
 
   return template;
-};
+}
 
-const buildIssueUrl = ({ title, config }) => {
+function buildIssueUrl({ title, config }) {
   try {
     const body = buildIssueTemplate({ config });
 
@@ -63,7 +66,7 @@ const buildIssueUrl = ({ title, config }) => {
     console.log(e);
     return `${ISSUE_URL}template=bug_report.md`;
   }
-};
+}
 
 const ErrorBoundaryContainer = styled.div`
   padding: 40px;
@@ -107,7 +110,7 @@ const CopyButton = styled.button`
   margin: 12px 0;
 `;
 
-const RecoveredEntry = ({ entry, t }) => {
+function RecoveredEntry({ entry, t }) {
   console.log(entry);
   return (
     <>
@@ -122,7 +125,7 @@ const RecoveredEntry = ({ entry, t }) => {
       </pre>
     </>
   );
-};
+}
 
 export class ErrorBoundary extends React.Component {
   static propTypes = {

packages/netlify-cms-core/src/components/UI/FileUploadButton.js

@@ -1,7 +1,8 @@
 import React from 'react';
 import PropTypes from 'prop-types';
 
-export const FileUploadButton = ({ label, imagesOnly, onChange, disabled, className }) => (
+export function FileUploadButton({ label, imagesOnly, onChange, disabled, className }) {
+  return (
     <label className={`nc-fileUploadButton ${className || ''}`}>
       <span>{label}</span>
       <input
@@ -11,7 +12,8 @@ export const FileUploadButton = ({ label, imagesOnly, onChange, disabled, classN
         disabled={disabled}
       />
     </label>
-);
+  );
+}
 
 FileUploadButton.propTypes = {
   className: PropTypes.string,

packages/netlify-cms-core/src/components/UI/Modal.js

@@ -4,7 +4,8 @@ import { css, Global, ClassNames } from '@emotion/core';
 import ReactModal from 'react-modal';
 import { transitions, shadows, lengths, zIndex } from 'netlify-cms-ui-default';
 
-const ReactModalGlobalStyles = () => (
+function ReactModalGlobalStyles() {
+  return (
     <Global
       styles={css`
         .ReactModal__Body--open {
@@ -12,7 +13,8 @@ const ReactModalGlobalStyles = () => (
         }
       `}
     />
-);
+  );
+}
 
 const styleStrings = {
   modalBody: `

packages/netlify-cms-core/src/components/UI/SettingsDropdown.js

@@ -46,14 +46,20 @@ const AppHeaderTestRepoIndicator = styled.a`
   padding: 10px 16px;
 `;
 
-const Avatar = ({ imageUrl }) =>
+function Avatar({ imageUrl }) {
-  imageUrl ? <AvatarImage src={imageUrl} /> : <AvatarPlaceholderIcon type="user" size="large" />;
+  return imageUrl ? (
+    <AvatarImage src={imageUrl} />
+  ) : (
+    <AvatarPlaceholderIcon type="user" size="large" />
+  );
+}
 
 Avatar.propTypes = {
   imageUrl: PropTypes.string,
 };
 
-const SettingsDropdown = ({ displayUrl, isTestRepo, imageUrl, onLogoutClick, t }) => (
+function SettingsDropdown({ displayUrl, isTestRepo, imageUrl, onLogoutClick, t }) {
+  return (
     <React.Fragment>
       {isTestRepo && (
         <AppHeaderTestRepoIndicator
@@ -82,7 +88,8 @@ const SettingsDropdown = ({ displayUrl, isTestRepo, imageUrl, onLogoutClick, t }
         <DropdownItem label={t('ui.settingsDropdown.logOut')} onClick={onLogoutClick} />
       </Dropdown>
     </React.Fragment>
-);
+  );
+}
 
 SettingsDropdown.propTypes = {
   displayUrl: PropTypes.string,

packages/netlify-cms-core/src/components/UI/Toast.js

@@ -6,7 +6,8 @@ import { translate } from 'react-polyglot';
 import reduxNotificationsStyles from 'redux-notifications/lib/styles.css';
 import { shadows, colors, lengths, zIndex } from 'netlify-cms-ui-default';
 
-const ReduxNotificationsGlobalStyles = () => (
+function ReduxNotificationsGlobalStyles() {
+  return (
     <Global
       styles={css`
         ${reduxNotificationsStyles};
@@ -17,7 +18,8 @@ const ReduxNotificationsGlobalStyles = () => (
         }
       `}
     />
-);
+  );
+}
 
 const styles = {
   toast: css`
@@ -47,12 +49,14 @@ const styles = {
   `,
 };
 
-const Toast = ({ kind, message, t }) => (
+function Toast({ kind, message, t }) {
+  return (
     <div css={[styles.toast, styles[kind]]}>
       <ReduxNotificationsGlobalStyles />
       {t(message.key, { details: message.details })}
     </div>
-);
+  );
+}
 
 Toast.propTypes = {
   kind: PropTypes.oneOf(['info', 'success', 'warning', 'danger']).isRequired,

packages/netlify-cms-core/src/components/UI/__tests__/ErrorBoundary.spec.js

@@ -4,9 +4,9 @@ import { render } from '@testing-library/react';
 import { fromJS } from 'immutable';
 import { oneLineTrim } from 'common-tags';
 
-const WithError = () => {
+function WithError() {
   throw new Error('Some unknown error');
-};
+}
 
 jest.spyOn(console, 'error').mockImplementation(() => ({}));
 

packages/netlify-cms-core/src/components/Workflow/WorkflowCard.js

@@ -98,7 +98,7 @@ const WorkflowCardContainer = styled.div`
   }
 `;
 
-const lastChangePhraseKey = (date, author) => {
+function lastChangePhraseKey(date, author) {
   if (date && author) {
     return 'lastChange';
   } else if (date) {
@@ -106,7 +106,7 @@ const lastChangePhraseKey = (date, author) => {
   } else if (author) {
     return 'lastChangeNoDate';
   }
-};
+}
 
 const CardDate = translate()(({ t, date, author }) => {
   const key = lastChangePhraseKey(date, author);
@@ -117,7 +117,7 @@ const CardDate = translate()(({ t, date, author }) => {
   }
 });
 
-const WorkflowCard = ({
+function WorkflowCard({
   collectionLabel,
   title,
   authorLastChange,
@@ -130,7 +130,8 @@ const WorkflowCard = ({
   canPublish,
   onPublish,
   t,
-}) => (
+}) {
+  return (
     <WorkflowCardContainer>
       <WorkflowLink to={editLink}>
         <CardCollection>{collectionLabel}</CardCollection>
@@ -153,7 +154,8 @@ const WorkflowCard = ({
         )}
       </CardButtonContainer>
     </WorkflowCardContainer>
-);
+  );
+}
 
 WorkflowCard.propTypes = {
   collectionLabel: PropTypes.string.isRequired,

packages/netlify-cms-core/src/components/Workflow/WorkflowList.js

@@ -116,7 +116,7 @@ const ColumnCount = styled.p`
 // This is a namespace so that we can only drop these elements on a DropTarget with the same
 const DNDNamespace = 'cms-workflow';
 
-const getColumnHeaderText = (columnName, t) => {
+function getColumnHeaderText(columnName, t) {
   switch (columnName) {
     case 'draft':
       return t('workflow.workflowList.draftHeader');
@@ -125,7 +125,7 @@ const getColumnHeaderText = (columnName, t) => {
     case 'pending_publish':
       return t('workflow.workflowList.readyHeader');
   }
-};
+}
 
 class WorkflowList extends React.Component {
   static propTypes = {

packages/netlify-cms-core/src/constants/configSchema.js

@@ -43,7 +43,7 @@ const i18nField = {
 /**
  * Config for fields in both file and folder collections.
  */
-const fieldsConfig = () => {
+function fieldsConfig() {
   const id = uuid();
   return {
     $id: `fields_${id}`,
@@ -77,7 +77,7 @@ const fieldsConfig = () => {
     },
     uniqueItemProperties: ['name'],
   };
-};
+}
 
 const viewFilters = {
   type: 'array',
@@ -121,7 +121,8 @@ const viewGroups = {
  * fix a circular dependency problem for WebPack,
  * where the imports get resolved asynchronously.
  */
-const getConfigSchema = () => ({
+function getConfigSchema() {
+  return {
     type: 'object',
     properties: {
       backend: {
@@ -315,7 +316,8 @@ const getConfigSchema = () => ({
     },
     required: ['backend', 'collections'],
     anyOf: [{ required: ['media_folder'] }, { required: ['media_library'] }],
-});
+  };
+}
 
 function getWidgetSchemas() {
   const schemas = getWidgets().map(widget => ({ [widget.name]: widget.schema }));

packages/netlify-cms-core/src/formats/formats.js

@@ -28,8 +28,8 @@ export const extensionFormatters = {
   html: FrontmatterInfer,
 };
 
-const formatByName = (name, customDelimiter) =>
+function formatByName(name, customDelimiter) {
-  ({
+  return {
     yml: yamlFormatter,
     yaml: yamlFormatter,
     toml: tomlFormatter,
@@ -38,7 +38,8 @@ const formatByName = (name, customDelimiter) =>
     'json-frontmatter': frontmatterJSON(customDelimiter),
     'toml-frontmatter': frontmatterTOML(customDelimiter),
     'yaml-frontmatter': frontmatterYAML(customDelimiter),
-  }[name]);
+  }[name];
+}
 
 export function resolveFormat(collection, entry) {
   // Check for custom delimiter

packages/netlify-cms-core/src/formats/frontmatter.js

@@ -51,12 +51,13 @@ function inferFrontmatterFormat(str) {
   }
 }
 
-export const getFormatOpts = format =>
+export function getFormatOpts(format) {
-  ({
+  return {
     yaml: { language: 'yaml', delimiters: '---' },
     toml: { language: 'toml', delimiters: '+++' },
     json: { language: 'json', delimiters: ['{', '}'] },
-  }[format]);
+  }[format];
+}
 
 class FrontmatterFormatter {
   constructor(format, customDelimiter) {
@@ -99,6 +100,15 @@ class FrontmatterFormatter {
 }
 
 export const FrontmatterInfer = new FrontmatterFormatter();
-export const frontmatterYAML = customDelimiter => new FrontmatterFormatter('yaml', customDelimiter);
+
-export const frontmatterTOML = customDelimiter => new FrontmatterFormatter('toml', customDelimiter);
+export function frontmatterYAML(customDelimiter) {
-export const frontmatterJSON = customDelimiter => new FrontmatterFormatter('json', customDelimiter);
+  return new FrontmatterFormatter('yaml', customDelimiter);
+}
+
+export function frontmatterTOML(customDelimiter) {
+  return new FrontmatterFormatter('toml', customDelimiter);
+}
+
+export function frontmatterJSON(customDelimiter) {
+  return new FrontmatterFormatter('json', customDelimiter);
+}

packages/netlify-cms-core/src/formats/helpers.js

@@ -1,8 +1,10 @@
-export const sortKeys = (sortedKeys = [], selector = a => a) => (a, b) => {
+export function sortKeys(sortedKeys = [], selector = a => a) {
+  return (a, b) => {
     const idxA = sortedKeys.indexOf(selector(a));
     const idxB = sortedKeys.indexOf(selector(b));
     if (idxA === -1 || idxB === -1) return 0;
     if (idxA > idxB) return 1;
     if (idxA < idxB) return -1;
     return 0;
-};
+  };
+}

packages/netlify-cms-core/src/formats/toml.js

@@ -4,7 +4,7 @@ import moment from 'moment';
 import AssetProxy from 'ValueObjects/AssetProxy';
 import { sortKeys } from './helpers';
 
-const outputReplacer = (key, value) => {
+function outputReplacer(key, value) {
   if (moment.isMoment(value)) {
     return value.format(value._f);
   }
@@ -17,7 +17,7 @@ const outputReplacer = (key, value) => {
   }
   // Return `false` to use default (`undefined` would delete key).
   return false;
-};
+}
 
 export default {
   fromFile(content) {

packages/netlify-cms-core/src/formats/yaml.js

@@ -1,7 +1,7 @@
 import yaml from 'yaml';
 import { sortKeys } from './helpers';
 
-const addComments = (items, comments, prefix = '') => {
+function addComments(items, comments, prefix = '') {
   items.forEach(item => {
     if (item.key !== undefined) {
       const itemKey = item.key.toString();
@@ -15,7 +15,7 @@ const addComments = (items, comments, prefix = '') => {
       }
     }
   });
-};
+}
 
 const timestampTag = {
   identify: value => value instanceof Date,

packages/netlify-cms-core/src/lib/formatters.ts

@@ -41,12 +41,12 @@ type Options = {
   authorName?: string;
 };
 
-export const commitMessageFormatter = (
+export function commitMessageFormatter(
   type: string,
   config: Config,
   { slug, path, collection, authorLogin, authorName }: Options,
   isOpenAuthoring?: boolean,
-) => {
+) {
   const templates = commitMessageTemplates.merge(
     config.getIn(['backend', 'commit_messages'], Map<string, string>()),
   );
@@ -88,9 +88,9 @@ export const commitMessageFormatter = (
   });
 
   return message;
-};
+}
 
-export const prepareSlug = (slug: string) => {
+export function prepareSlug(slug: string) {
   return (
     slug
       .trim()
@@ -103,20 +103,20 @@ export const prepareSlug = (slug: string) => {
       // Replace periods with dashes.
       .replace(/[.]/g, '-')
   );
-};
+}
 
-export const getProcessSegment = (slugConfig: SlugConfig, ignoreValues: string[] = []) => {
+export function getProcessSegment(slugConfig: SlugConfig, ignoreValues: string[] = []) {
   return (value: string) =>
     ignoreValues.includes(value)
       ? value
       : flow([value => String(value), prepareSlug, partialRight(sanitizeSlug, slugConfig)])(value);
-};
+}
 
-export const slugFormatter = (
+export function slugFormatter(
   collection: Collection,
   entryData: Map<string, unknown>,
   slugConfig: SlugConfig,
-) => {
+) {
   const slugTemplate = collection.get('slug') || '{{slug}}';
 
   const identifier = entryData.getIn(keyToPathArray(selectIdentifier(collection) as string));
@@ -138,15 +138,15 @@ export const slugFormatter = (
       value === slug ? value : processSegment(value),
     );
   }
-};
+}
 
-export const previewUrlFormatter = (
+export function previewUrlFormatter(
   baseUrl: string,
   collection: Collection,
   slug: string,
   slugConfig: SlugConfig,
   entry: EntryMap,
-) => {
+) {
   /**
    * Preview URL can't be created without `baseUrl`. This makes preview URLs
    * optional for backends that don't support them.
@@ -160,12 +160,13 @@ export const previewUrlFormatter = (
   const isFileCollection = collection.get('type') === FILES;
   const file = isFileCollection ? getFileFromSlug(collection, entry.get('slug')) : undefined;
 
-  const getPathTemplate = () => {
+  function getPathTemplate() {
     return file?.get('preview_path') ?? collection.get('preview_path');
-  };
+  }
-  const getDateField = () => {
+
+  function getDateField() {
     return file?.get('preview_path_date_field') ?? collection.get('preview_path_date_field');
-  };
+  }
 
   /**
    * If a `previewPath` is provided for the collection/file, use it to construct the
@@ -209,13 +210,9 @@ export const previewUrlFormatter = (
 
   const previewPath = trimStart(compiledPath, ' /');
   return `${basePath}/${previewPath}`;
-};
+}
 
-export const summaryFormatter = (
+export function summaryFormatter(summaryTemplate: string, entry: EntryMap, collection: Collection) {
-  summaryTemplate: string,
-  entry: EntryMap,
-  collection: Collection,
-) => {
   let entryData = entry.get('data');
   const date =
     parseDateFromEntry(
@@ -234,16 +231,16 @@ export const summaryFormatter = (
   }
   const summary = compileStringTemplate(summaryTemplate, date, identifier, entryData);
   return summary;
-};
+}
 
-export const folderFormatter = (
+export function folderFormatter(
   folderTemplate: string,
   entry: EntryMap | undefined,
   collection: Collection,
   defaultFolder: string,
   folderKey: string,
   slugConfig: SlugConfig,
-) => {
+) {
   if (!entry || !entry.get('data')) {
     return folderTemplate;
   }
@@ -268,4 +265,4 @@ export const folderFormatter = (
   );
 
   return mediaFolder;
-};
+}

packages/netlify-cms-core/src/lib/i18n.ts

@@ -18,9 +18,9 @@ export enum I18N_FIELD {
   NONE = 'none',
 }
 
-export const hasI18n = (collection: Collection) => {
+export function hasI18n(collection: Collection) {
   return collection.has(I18N);
-};
+}
 
 type I18nInfo = {
   locales: string[];
@@ -28,53 +28,53 @@ type I18nInfo = {
   structure: I18N_STRUCTURE;
 };
 
-export const getI18nInfo = (collection: Collection) => {
+export function getI18nInfo(collection: Collection) {
   if (!hasI18n(collection)) {
     return {};
   }
   const { structure, locales, default_locale: defaultLocale } = collection.get(I18N).toJS();
   return { structure, locales, defaultLocale } as I18nInfo;
-};
+}
 
-export const getI18nFilesDepth = (collection: Collection, depth: number) => {
+export function getI18nFilesDepth(collection: Collection, depth: number) {
   const { structure } = getI18nInfo(collection) as I18nInfo;
   if (structure === I18N_STRUCTURE.MULTIPLE_FOLDERS) {
     return depth + 1;
   }
   return depth;
-};
+}
 
-export const isFieldTranslatable = (field: EntryField, locale: string, defaultLocale: string) => {
+export function isFieldTranslatable(field: EntryField, locale: string, defaultLocale: string) {
   const isTranslatable = locale !== defaultLocale && field.get(I18N) === I18N_FIELD.TRANSLATE;
   return isTranslatable;
-};
+}
 
-export const isFieldDuplicate = (field: EntryField, locale: string, defaultLocale: string) => {
+export function isFieldDuplicate(field: EntryField, locale: string, defaultLocale: string) {
   const isDuplicate = locale !== defaultLocale && field.get(I18N) === I18N_FIELD.DUPLICATE;
   return isDuplicate;
-};
+}
 
-export const isFieldHidden = (field: EntryField, locale: string, defaultLocale: string) => {
+export function isFieldHidden(field: EntryField, locale: string, defaultLocale: string) {
   const isHidden = locale !== defaultLocale && field.get(I18N) === I18N_FIELD.NONE;
   return isHidden;
-};
+}
 
-export const getLocaleDataPath = (locale: string) => {
+export function getLocaleDataPath(locale: string) {
   return [I18N, locale, 'data'];
-};
+}
 
-export const getDataPath = (locale: string, defaultLocale: string) => {
+export function getDataPath(locale: string, defaultLocale: string) {
   const dataPath = locale !== defaultLocale ? getLocaleDataPath(locale) : ['data'];
   return dataPath;
-};
+}
 
-export const getFilePath = (
+export function getFilePath(
   structure: I18N_STRUCTURE,
   extension: string,
   path: string,
   slug: string,
   locale: string,
-) => {
+) {
   switch (structure) {
     case I18N_STRUCTURE.MULTIPLE_FOLDERS:
       return path.replace(`/${slug}`, `/${locale}/${slug}`);
@@ -84,9 +84,9 @@ export const getFilePath = (
     default:
       return path;
   }
-};
+}
 
-export const getLocaleFromPath = (structure: I18N_STRUCTURE, extension: string, path: string) => {
+export function getLocaleFromPath(structure: I18N_STRUCTURE, extension: string, path: string) {
   switch (structure) {
     case I18N_STRUCTURE.MULTIPLE_FOLDERS: {
       const parts = path.split('/');
@@ -103,23 +103,23 @@ export const getLocaleFromPath = (structure: I18N_STRUCTURE, extension: string,
     default:
       return '';
   }
-};
+}
 
-export const getFilePaths = (
+export function getFilePaths(
   collection: Collection,
   extension: string,
   path: string,
   slug: string,
-) => {
+) {
   const { structure, locales } = getI18nInfo(collection) as I18nInfo;
   const paths = locales.map(locale =>
     getFilePath(structure as I18N_STRUCTURE, extension, path, slug, locale),
   );
 
   return paths;
-};
+}
 
-export const normalizeFilePath = (structure: I18N_STRUCTURE, path: string, locale: string) => {
+export function normalizeFilePath(structure: I18N_STRUCTURE, path: string, locale: string) {
   switch (structure) {
     case I18N_STRUCTURE.MULTIPLE_FOLDERS:
       return path.replace(`${locale}/`, '');
@@ -129,9 +129,9 @@ export const normalizeFilePath = (structure: I18N_STRUCTURE, path: string, local
     default:
       return path;
   }
-};
+}
 
-export const getI18nFiles = (
+export function getI18nFiles(
   collection: Collection,
   extension: string,
   entryDraft: EntryMap,
@@ -139,7 +139,7 @@ export const getI18nFiles = (
   path: string,
   slug: string,
   newPath?: string,
-) => {
+) {
   const { structure, defaultLocale, locales } = getI18nInfo(collection) as I18nInfo;
 
   if (structure === I18N_STRUCTURE.SINGLE_FILE) {
@@ -176,13 +176,13 @@ export const getI18nFiles = (
     })
     .filter(dataFile => dataFile.raw);
   return dataFiles;
-};
+}
 
-export const getI18nBackup = (
+export function getI18nBackup(
   collection: Collection,
   entry: EntryMap,
   entryToRaw: (entry: EntryMap) => string,
-) => {
+) {
   const { locales, defaultLocale } = getI18nInfo(collection) as I18nInfo;
 
   const i18nBackup = locales
@@ -198,26 +198,26 @@ export const getI18nBackup = (
     }, {} as Record<string, { raw: string }>);
 
   return i18nBackup;
-};
+}
 
-export const formatI18nBackup = (
+export function formatI18nBackup(
   i18nBackup: Record<string, { raw: string }>,
   formatRawData: (raw: string) => EntryValue,
-) => {
+) {
   const i18n = Object.entries(i18nBackup).reduce((acc, [locale, { raw }]) => {
     const entry = formatRawData(raw);
     return { ...acc, [locale]: { data: entry.data } };
   }, {});
 
   return i18n;
-};
+}
 
-const mergeValues = (
+function mergeValues(
   collection: Collection,
   structure: I18N_STRUCTURE,
   defaultLocale: string,
   values: { locale: string; value: EntryValue }[],
-) => {
+) {
   let defaultEntry = values.find(e => e.locale === defaultLocale);
   if (!defaultEntry) {
     defaultEntry = values[0];
@@ -241,9 +241,9 @@ const mergeValues = (
   };
 
   return entryValue;
-};
+}
 
-const mergeSingleFileValue = (entryValue: EntryValue, defaultLocale: string, locales: string[]) => {
+function mergeSingleFileValue(entryValue: EntryValue, defaultLocale: string, locales: string[]) {
   const data = entryValue.data[defaultLocale] || {};
   const i18n = locales
     .filter(l => l !== defaultLocale)
@@ -259,15 +259,15 @@ const mergeSingleFileValue = (entryValue: EntryValue, defaultLocale: string, loc
     i18n,
     raw: '',
   };
-};
+}
 
-export const getI18nEntry = async (
+export async function getI18nEntry(
   collection: Collection,
   extension: string,
   path: string,
   slug: string,
   getEntryValue: (path: string) => Promise<EntryValue>,
-) => {
+) {
   const { structure, locales, defaultLocale } = getI18nInfo(collection) as I18nInfo;
 
   let entryValue: EntryValue;
@@ -291,9 +291,9 @@ export const getI18nEntry = async (
   }
 
   return entryValue;
-};
+}
 
-export const groupEntries = (collection: Collection, extension: string, entries: EntryValue[]) => {
+export function groupEntries(collection: Collection, extension: string, entries: EntryValue[]) {
   const { structure, defaultLocale, locales } = getI18nInfo(collection) as I18nInfo;
   if (structure === I18N_STRUCTURE.SINGLE_FILE) {
     return entries.map(e => mergeSingleFileValue(e, defaultLocale, locales));
@@ -315,15 +315,15 @@ export const groupEntries = (collection: Collection, extension: string, entries:
   }, [] as EntryValue[]);
 
   return groupedEntries;
-};
+}
 
-export const getI18nDataFiles = (
+export function getI18nDataFiles(
   collection: Collection,
   extension: string,
   path: string,
   slug: string,
   diffFiles: { path: string; id: string; newFile: boolean }[],
-) => {
+) {
   const { structure } = getI18nInfo(collection) as I18nInfo;
   if (structure === I18N_STRUCTURE.SINGLE_FILE) {
     return diffFiles;
@@ -339,10 +339,10 @@ export const getI18nDataFiles = (
   }, [] as { path: string; id: string; newFile: boolean }[]);
 
   return dataFiles;
-};
+}
 
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
-export const duplicateDefaultI18nFields = (collection: Collection, dataFields: any) => {
+export function duplicateDefaultI18nFields(collection: Collection, dataFields: any) {
   const { locales, defaultLocale } = getI18nInfo(collection) as I18nInfo;
 
   const i18nFields = Object.fromEntries(
@@ -352,15 +352,15 @@ export const duplicateDefaultI18nFields = (collection: Collection, dataFields: a
   );
 
   return i18nFields;
-};
+}
 
-export const duplicateI18nFields = (
+export function duplicateI18nFields(
   entryDraft: EntryDraft,
   field: EntryField,
   locales: string[],
   defaultLocale: string,
   fieldPath: string[] = [field.get('name')],
-) => {
+) {
   const value = entryDraft.getIn(['entry', 'data', ...fieldPath]);
   if (field.get(I18N) === I18N_FIELD.DUPLICATE) {
     locales
@@ -392,21 +392,21 @@ export const duplicateI18nFields = (
   }
 
   return entryDraft;
-};
+}
 
-export const getPreviewEntry = (entry: EntryMap, locale: string, defaultLocale: string) => {
+export function getPreviewEntry(entry: EntryMap, locale: string, defaultLocale: string) {
   if (locale === defaultLocale) {
     return entry;
   }
   return entry.set('data', entry.getIn([I18N, locale, 'data']));
-};
+}
 
-export const serializeI18n = (
+export function serializeI18n(
   collection: Collection,
   entry: Entry,
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
   serializeValues: (data: any) => any,
-) => {
+) {
   const { locales, defaultLocale } = getI18nInfo(collection) as I18nInfo;
 
   locales
@@ -417,4 +417,4 @@ export const serializeI18n = (
     });
 
   return entry;
-};
+}

packages/netlify-cms-core/src/lib/serializeEntryValues.js

@@ -20,7 +20,7 @@ import { getWidgetValueSerializer } from './registry';
  * registered deserialization handlers run on entry load, and serialization
  * handlers run on persist.
  */
-const runSerializer = (values, fields, method) => {
+function runSerializer(values, fields, method) {
   /**
    * Reduce the list of fields to a map where keys are field names and values
    * are field values, serializing the values of fields whose widgets have
@@ -63,12 +63,12 @@ const runSerializer = (values, fields, method) => {
   serializedData = values.mergeDeep(serializedData);
 
   return serializedData;
-};
+}
 
-export const serializeValues = (values, fields) => {
+export function serializeValues(values, fields) {
   return runSerializer(values, fields, 'serialize');
-};
+}
 
-export const deserializeValues = (values, fields) => {
+export function deserializeValues(values, fields) {
   return runSerializer(values, fields, 'deserialize');
-};
+}

packages/netlify-cms-core/src/lib/urlHelper.ts

@@ -36,8 +36,14 @@ export function stripProtocol(urlString: string) {
  */
 const uriChars = /[\w\-.~]/i;
 const ucsChars = /[\xA0-\u{D7FF}\u{F900}-\u{FDCF}\u{FDF0}-\u{FFEF}\u{10000}-\u{1FFFD}\u{20000}-\u{2FFFD}\u{30000}-\u{3FFFD}\u{40000}-\u{4FFFD}\u{50000}-\u{5FFFD}\u{60000}-\u{6FFFD}\u{70000}-\u{7FFFD}\u{80000}-\u{8FFFD}\u{90000}-\u{9FFFD}\u{A0000}-\u{AFFFD}\u{B0000}-\u{BFFFD}\u{C0000}-\u{CFFFD}\u{D0000}-\u{DFFFD}\u{E1000}-\u{EFFFD}]/u;
-const validURIChar = (char: string) => uriChars.test(char);
+
-const validIRIChar = (char: string) => uriChars.test(char) || ucsChars.test(char);
+function validURIChar(char: string) {
+  return uriChars.test(char);
+}
+
+function validIRIChar(char: string) {
+  return uriChars.test(char) || ucsChars.test(char);
+}
 
 export function getCharReplacer(encoding: string, replacement: string) {
   let validChar: (char: string) => boolean;

packages/netlify-cms-core/src/mediaLibrary.ts

@@ -18,6 +18,12 @@ interface MediaLibrary {
   }) => MediaLibraryInstance;
 }
 
+function handleInsert(url: string) {
+  // eslint-disable-next-line @typescript-eslint/ban-ts-ignore
+  // @ts-ignore
+  return store.dispatch(insertMedia(url, undefined));
+}
+
 const initializeMediaLibrary = once(async function initializeMediaLibrary(name, options) {
   const lib = (getMediaLibrary(name) as unknown) as MediaLibrary | undefined;
   if (!lib) {
@@ -26,9 +32,6 @@ const initializeMediaLibrary = once(async function initializeMediaLibrary(name,
     );
     store.dispatch(configFailed(err));
   } else {
-    // eslint-disable-next-line @typescript-eslint/ban-ts-ignore
-    // @ts-ignore
-    const handleInsert = (url: string) => store.dispatch(insertMedia(url, undefined));
     const instance = await lib.init({ options, handleInsert });
     store.dispatch(createMediaLibrary(instance));
   }

packages/netlify-cms-core/src/reducers/__tests__/collections.spec.js

@@ -460,7 +460,9 @@ describe('collections', () => {
         ],
       });
 
-      const updater = field => field.set('default', 'default');
+      function updater(field) {
+        return field.set('default', 'default');
+      }
 
       expect(updateFieldByKey(collection, 'non-existent', updater)).toBe(collection);
       expect(updateFieldByKey(collection, 'title', updater)).toEqual(

packages/netlify-cms-core/src/reducers/collections.ts

@@ -22,7 +22,7 @@ import { Backend } from '../backend';
 
 const { keyToPathArray } = stringTemplate;
 
-const collections = (state = null, action: CollectionsAction) => {
+function collections(state = null, action: CollectionsAction) {
   switch (action.type) {
     case CONFIG_SUCCESS: {
       const configCollections = action.payload
@@ -49,7 +49,7 @@ const collections = (state = null, action: CollectionsAction) => {
     default:
       return state;
   }
-};
+}
 
 const selectors = {
   [FOLDER]: {
@@ -120,7 +120,7 @@ const selectors = {
   },
 };
 
-const getFieldsWithMediaFolders = (fields: EntryField[]) => {
+function getFieldsWithMediaFolders(fields: EntryField[]) {
   const fieldsWithMediaFolders = fields.reduce((acc, f) => {
     if (f.has('media_folder')) {
       acc = [...acc, f];
@@ -141,16 +141,16 @@ const getFieldsWithMediaFolders = (fields: EntryField[]) => {
   }, [] as EntryField[]);
 
   return fieldsWithMediaFolders;
-};
+}
 
-export const getFileFromSlug = (collection: Collection, slug: string) => {
+export function getFileFromSlug(collection: Collection, slug: string) {
   return collection
     .get('files')
     ?.toArray()
     .find(f => f.get('name') === slug);
-};
+}
 
-export const selectFieldsWithMediaFolders = (collection: Collection, slug: string) => {
+export function selectFieldsWithMediaFolders(collection: Collection, slug: string) {
   if (collection.has('folder')) {
     const fields = collection.get('fields').toArray();
     return getFieldsWithMediaFolders(fields);
@@ -163,9 +163,9 @@ export const selectFieldsWithMediaFolders = (collection: Collection, slug: strin
   }
 
   return [];
-};
+}
 
-export const selectMediaFolders = (state: State, collection: Collection, entry: EntryMap) => {
+export function selectMediaFolders(state: State, collection: Collection, entry: EntryMap) {
   const fields = selectFieldsWithMediaFolders(collection, entry.get('slug'));
   const folders = fields.map(f => selectMediaFolder(state.config, collection, entry, f));
   if (collection.has('files')) {
@@ -181,26 +181,41 @@ export const selectMediaFolders = (state: State, collection: Collection, entry:
   }
 
   return Set(folders).toArray();
-};
+}
 
-export const selectFields = (collection: Collection, slug: string) =>
+export function selectFields(collection: Collection, slug: string) {
-  selectors[collection.get('type')].fields(collection, slug);
+  return selectors[collection.get('type')].fields(collection, slug);
-export const selectFolderEntryExtension = (collection: Collection) =>
+}
-  selectors[FOLDER].entryExtension(collection);
-export const selectFileEntryLabel = (collection: Collection, slug: string) =>
-  selectors[FILES].entryLabel(collection, slug);
-export const selectEntryPath = (collection: Collection, slug: string) =>
-  selectors[collection.get('type')].entryPath(collection, slug);
-export const selectEntrySlug = (collection: Collection, path: string) =>
-  selectors[collection.get('type')].entrySlug(collection, path);
-export const selectAllowNewEntries = (collection: Collection) =>
-  selectors[collection.get('type')].allowNewEntries(collection);
-export const selectAllowDeletion = (collection: Collection) =>
-  selectors[collection.get('type')].allowDeletion(collection);
-export const selectTemplateName = (collection: Collection, slug: string) =>
-  selectors[collection.get('type')].templateName(collection, slug);
 
-export const getFieldsNames = (fields: EntryField[], prefix = '') => {
+export function selectFolderEntryExtension(collection: Collection) {
+  return selectors[FOLDER].entryExtension(collection);
+}
+
+export function selectFileEntryLabel(collection: Collection, slug: string) {
+  return selectors[FILES].entryLabel(collection, slug);
+}
+
+export function selectEntryPath(collection: Collection, slug: string) {
+  return selectors[collection.get('type')].entryPath(collection, slug);
+}
+
+export function selectEntrySlug(collection: Collection, path: string) {
+  return selectors[collection.get('type')].entrySlug(collection, path);
+}
+
+export function selectAllowNewEntries(collection: Collection) {
+  return selectors[collection.get('type')].allowNewEntries(collection);
+}
+
+export function selectAllowDeletion(collection: Collection) {
+  return selectors[collection.get('type')].allowDeletion(collection);
+}
+
+export function selectTemplateName(collection: Collection, slug: string) {
+  return selectors[collection.get('type')].templateName(collection, slug);
+}
+
+export function getFieldsNames(fields: EntryField[], prefix = '') {
   let names = fields.map(f => `${prefix}${f.get('name')}`);
 
   fields.forEach((f, index) => {
@@ -217,9 +232,9 @@ export const getFieldsNames = (fields: EntryField[], prefix = '') => {
   });
 
   return names;
-};
+}
 
-export const selectField = (collection: Collection, key: string) => {
+export function selectField(collection: Collection, key: string) {
   const array = keyToPathArray(key);
   let name: string | undefined;
   let field;
@@ -236,13 +251,13 @@ export const selectField = (collection: Collection, key: string) => {
   }
 
   return field;
-};
+}
 
-export const traverseFields = (
+export function traverseFields(
   fields: List<EntryField>,
   updater: (field: EntryField) => EntryField,
   done = () => false,
-) => {
+) {
   if (done()) {
     return fields;
   }
@@ -268,20 +283,21 @@ export const traverseFields = (
     .toList() as List<EntryField>;
 
   return fields;
-};
+}
 
-export const updateFieldByKey = (
+export function updateFieldByKey(
   collection: Collection,
   key: string,
   updater: (field: EntryField) => EntryField,
-) => {
+) {
   const selected = selectField(collection, key);
   if (!selected) {
     return collection;
   }
 
   let updated = false;
-  const updateAndBreak = (f: EntryField) => {
+
+  function updateAndBreak(f: EntryField) {
     const field = f as EntryField;
     if (field === selected) {
       updated = true;
@@ -289,7 +305,7 @@ export const updateFieldByKey = (
     } else {
       return field;
     }
-  };
+  }
 
   collection = collection.set(
     'fields',
@@ -297,18 +313,18 @@ export const updateFieldByKey = (
   );
 
   return collection;
-};
+}
 
-export const selectIdentifier = (collection: Collection) => {
+export function selectIdentifier(collection: Collection) {
   const identifier = collection.get('identifier_field');
   const identifierFields = identifier ? [identifier, ...IDENTIFIER_FIELDS] : IDENTIFIER_FIELDS;
   const fieldNames = getFieldsNames(collection.get('fields', List<EntryField>()).toArray());
   return identifierFields.find(id =>
     fieldNames.find(name => name?.toLowerCase().trim() === id.toLowerCase().trim()),
   );
-};
+}
 
-export const selectInferedField = (collection: Collection, fieldName: string) => {
+export function selectInferedField(collection: Collection, fieldName: string) {
   if (fieldName === 'title' && collection.get('identifier_field')) {
     return selectIdentifier(collection);
   }
@@ -355,9 +371,9 @@ export const selectInferedField = (collection: Collection, fieldName: string) =>
   }
 
   return null;
-};
+}
 
-export const selectEntryCollectionTitle = (collection: Collection, entry: EntryMap) => {
+export function selectEntryCollectionTitle(collection: Collection, entry: EntryMap) {
   // prefer formatted summary over everything else
   const summaryTemplate = collection.get('summary');
   if (summaryTemplate) return summaryFormatter(summaryTemplate, entry, collection);
@@ -372,16 +388,16 @@ export const selectEntryCollectionTitle = (collection: Collection, entry: EntryM
   const entryData = entry.get('data');
   const titleField = selectInferedField(collection, 'title');
   return titleField && entryData.getIn(keyToPathArray(titleField));
-};
+}
 
 export const COMMIT_AUTHOR = 'commit_author';
 export const COMMIT_DATE = 'commit_date';
 
-export const selectDefaultSortableFields = (
+export function selectDefaultSortableFields(
   collection: Collection,
   backend: Backend,
   hasIntegration: boolean,
-) => {
+) {
   let defaultSortable = SORTABLE_FIELDS.map((type: string) => {
     const field = selectInferedField(collection, type);
     if (backend.isGitBackend() && type === 'author' && !field && !hasIntegration) {
@@ -397,9 +413,9 @@ export const selectDefaultSortableFields = (
   }
 
   return defaultSortable as string[];
-};
+}
 
-export const selectSortableFields = (collection: Collection, t: (key: string) => string) => {
+export function selectSortableFields(collection: Collection, t: (key: string) => string) {
   const fields = collection
     .get('sortable_fields')
     .toArray()
@@ -418,9 +434,9 @@ export const selectSortableFields = (collection: Collection, t: (key: string) =>
     .map(item => ({ ...item.field, key: item.key }));
 
   return fields;
-};
+}
 
-export const selectSortDataPath = (collection: Collection, key: string) => {
+export function selectSortDataPath(collection: Collection, key: string) {
   if (key === COMMIT_DATE) {
     return 'updatedOn';
   } else if (key === COMMIT_AUTHOR && !selectField(collection, key)) {
@@ -428,19 +444,19 @@ export const selectSortDataPath = (collection: Collection, key: string) => {
   } else {
     return `data.${key}`;
   }
-};
+}
 
-export const selectViewFilters = (collection: Collection) => {
+export function selectViewFilters(collection: Collection) {
   const viewFilters = collection.get('view_filters').toJS() as ViewFilter[];
   return viewFilters;
-};
+}
 
-export const selectViewGroups = (collection: Collection) => {
+export function selectViewGroups(collection: Collection) {
   const viewGroups = collection.get('view_groups').toJS() as ViewGroup[];
   return viewGroups;
-};
+}
 
-export const selectFieldsComments = (collection: Collection, entryMap: EntryMap) => {
+export function selectFieldsComments(collection: Collection, entryMap: EntryMap) {
   let fields: EntryField[] = [];
   if (collection.has('folder')) {
     fields = collection.get('fields').toArray();
@@ -458,15 +474,15 @@ export const selectFieldsComments = (collection: Collection, entryMap: EntryMap)
   });
 
   return comments;
-};
+}
 
-export const selectHasMetaPath = (collection: Collection) => {
+export function selectHasMetaPath(collection: Collection) {
   return (
     collection.has('folder') &&
     collection.get('type') === FOLDER &&
     collection.has('meta') &&
     collection.get('meta')?.has('path')
   );
-};
+}
 
 export default collections;

packages/netlify-cms-core/src/reducers/combinedReducer.js

@@ -3,12 +3,12 @@ import { connectRouter } from 'connected-react-router';
 import { reducer as notifReducer } from 'redux-notifications';
 import reducers from './index';
 
-const createRootReducer = history => {
+function createRootReducer(history) {
   return combineReducers({
     ...reducers,
     notifs: notifReducer,
     router: connectRouter(history),
   });
-};
+}
 
 export default createRootReducer;

packages/netlify-cms-core/src/reducers/config.ts

@@ -5,7 +5,7 @@ import { EDITORIAL_WORKFLOW } from '../constants/publishModes';
 
 const defaultState: Map<string, boolean | string> = Map({ isFetching: true });
 
-const config = (state = defaultState, action: ConfigAction) => {
+function config(state = defaultState, action: ConfigAction) {
   switch (action.type) {
     case CONFIG_REQUEST:
       return state.set('isFetching', true);
@@ -24,11 +24,14 @@ const config = (state = defaultState, action: ConfigAction) => {
     default:
       return state;
   }
-};
+}
 
-export const selectLocale = (state: Config) => state.get('locale', 'en') as string;
+export function selectLocale(state: Config) {
+  return state.get('locale', 'en') as string;
+}
 
-export const selectUseWorkflow = (state: Config) =>
+export function selectUseWorkflow(state: Config) {
-  state.get('publish_mode') === EDITORIAL_WORKFLOW;
+  return state.get('publish_mode') === EDITORIAL_WORKFLOW;
+}
 
 export default config;

packages/netlify-cms-core/src/reducers/cursors.js

@@ -10,10 +10,11 @@ import {
 // Since pagination can be used for a variety of views (collections
 // and searches are the most common examples), we namespace cursors by
 // their type before storing them in the state.
-export const selectCollectionEntriesCursor = (state, collectionName) =>
+export function selectCollectionEntriesCursor(state, collectionName) {
-  new Cursor(state.getIn(['cursorsByType', 'collectionEntries', collectionName]));
+  return new Cursor(state.getIn(['cursorsByType', 'collectionEntries', collectionName]));
+}
 
-const cursors = (state = fromJS({ cursorsByType: { collectionEntries: {} } }), action) => {
+function cursors(state = fromJS({ cursorsByType: { collectionEntries: {} } }), action) {
   switch (action.type) {
     case ENTRIES_SUCCESS: {
       return state.setIn(
@@ -29,6 +30,6 @@ const cursors = (state = fromJS({ cursorsByType: { collectionEntries: {} } }), a
     default:
       return state;
   }
-};
+}
 
 export default cursors;

packages/netlify-cms-core/src/reducers/deploys.js

@@ -5,7 +5,7 @@ import {
   DEPLOY_PREVIEW_FAILURE,
 } from 'Actions/deploys';
 
-const deploys = (state = Map({ deploys: Map() }), action) => {
+function deploys(state = Map({ deploys: Map() }), action) {
   switch (action.type) {
     case DEPLOY_PREVIEW_REQUEST: {
       const { collection, slug } = action.payload;
@@ -37,9 +37,10 @@ const deploys = (state = Map({ deploys: Map() }), action) => {
     default:
       return state;
   }
-};
+}
 
-export const selectDeployPreview = (state, collection, slug) =>
+export function selectDeployPreview(state, collection, slug) {
-  state.getIn(['deploys', `${collection}.${slug}`]);
+  return state.getIn(['deploys', `${collection}.${slug}`]);
+}
 
 export default deploys;

packages/netlify-cms-core/src/reducers/editorialWorkflow.ts

@@ -21,7 +21,7 @@ import {
 import { CONFIG_SUCCESS } from '../actions/config';
 import { EditorialWorkflowAction, EditorialWorkflow, Entities } from '../types/redux';
 
-const unpublishedEntries = (state = Map(), action: EditorialWorkflowAction) => {
+function unpublishedEntries(state = Map(), action: EditorialWorkflowAction) {
   switch (action.type) {
     case CONFIG_SUCCESS: {
       const publishMode = action.payload && action.payload.get('publish_mode');
@@ -137,27 +137,25 @@ const unpublishedEntries = (state = Map(), action: EditorialWorkflowAction) => {
     default:
       return state;
   }
-};
+}
 
-export const selectUnpublishedEntry = (
+export function selectUnpublishedEntry(state: EditorialWorkflow, collection: string, slug: string) {
-  state: EditorialWorkflow,
+  return state && state.getIn(['entities', `${collection}.${slug}`]);
-  collection: string,
+}
-  slug: string,
-) => state && state.getIn(['entities', `${collection}.${slug}`]);
 
-export const selectUnpublishedEntriesByStatus = (state: EditorialWorkflow, status: string) => {
+export function selectUnpublishedEntriesByStatus(state: EditorialWorkflow, status: string) {
   if (!state) return null;
   const entities = state.get('entities') as Entities;
   return entities.filter(entry => entry.get('status') === status).valueSeq();
-};
+}
 
-export const selectUnpublishedSlugs = (state: EditorialWorkflow, collection: string) => {
+export function selectUnpublishedSlugs(state: EditorialWorkflow, collection: string) {
   if (!state.get('entities')) return null;
   const entities = state.get('entities') as Entities;
   return entities
     .filter((_v, k) => startsWith(k as string, `${collection}.`))
     .map(entry => entry.get('slug'))
     .valueSeq();
-};
+}
 
 export default unpublishedEntries;

packages/netlify-cms-core/src/reducers/entries.ts

@@ -95,11 +95,11 @@ const loadSort = once(() => {
   return Map() as Sort;
 });
 
-const clearSort = () => {
+function clearSort() {
   localStorage.removeItem(storageSortKey);
-};
+}
 
-const persistSort = (sort: Sort | undefined) => {
+function persistSort(sort: Sort | undefined) {
   if (sort) {
     const storageSort: StorageSort = {};
     sort.keySeq().forEach(key => {
@@ -117,7 +117,7 @@ const persistSort = (sort: Sort | undefined) => {
   } else {
     clearSort();
   }
-};
+}
 
 const loadViewStyle = once(() => {
   const viewStyle = localStorage.getItem(viewStyleKey);
@@ -129,22 +129,22 @@ const loadViewStyle = once(() => {
   return VIEW_STYLE_LIST;
 });
 
-const clearViewStyle = () => {
+function clearViewStyle() {
   localStorage.removeItem(viewStyleKey);
-};
+}
 
-const persistViewStyle = (viewStyle: string | undefined) => {
+function persistViewStyle(viewStyle: string | undefined) {
   if (viewStyle) {
     localStorage.setItem(viewStyleKey, viewStyle);
   } else {
     clearViewStyle();
   }
-};
+}
 
-const entries = (
+function entries(
   state = Map({ entities: Map(), pages: Map(), sort: loadSort(), viewStyle: loadViewStyle() }),
   action: EntriesAction,
-) => {
+) {
   switch (action.type) {
     case ENTRY_REQUEST: {
       const payload = action.payload as EntryRequestPayload;
@@ -344,30 +344,30 @@ const entries = (
     default:
       return state;
   }
-};
+}
 
-export const selectEntriesSort = (entries: Entries, collection: string) => {
+export function selectEntriesSort(entries: Entries, collection: string) {
   const sort = entries.get('sort') as Sort | undefined;
   return sort?.get(collection);
-};
+}
 
-export const selectEntriesFilter = (entries: Entries, collection: string) => {
+export function selectEntriesFilter(entries: Entries, collection: string) {
   const filter = entries.get('filter') as Filter | undefined;
   return filter?.get(collection) || Map();
-};
+}
 
-export const selectEntriesGroup = (entries: Entries, collection: string) => {
+export function selectEntriesGroup(entries: Entries, collection: string) {
   const group = entries.get('group') as Group | undefined;
   return group?.get(collection) || Map();
-};
+}
 
-export const selectEntriesGroupField = (entries: Entries, collection: string) => {
+export function selectEntriesGroupField(entries: Entries, collection: string) {
   const groups = selectEntriesGroup(entries, collection);
   const value = groups?.valueSeq().find(v => v?.get('active') === true);
   return value;
-};
+}
 
-export const selectEntriesSortFields = (entries: Entries, collection: string) => {
+export function selectEntriesSortFields(entries: Entries, collection: string) {
   const sort = selectEntriesSort(entries, collection);
   const values =
     sort
@@ -376,9 +376,9 @@ export const selectEntriesSortFields = (entries: Entries, collection: string) =>
       .toArray() || [];
 
   return values;
-};
+}
 
-export const selectEntriesFilterFields = (entries: Entries, collection: string) => {
+export function selectEntriesFilterFields(entries: Entries, collection: string) {
   const filter = selectEntriesFilter(entries, collection);
   const values =
     filter
@@ -386,27 +386,29 @@ export const selectEntriesFilterFields = (entries: Entries, collection: string)
       .filter(v => v?.get('active') === true)
       .toArray() || [];
   return values;
-};
+}
 
-export const selectViewStyle = (entries: Entries) => {
+export function selectViewStyle(entries: Entries) {
   return entries.get('viewStyle');
-};
+}
 
-export const selectEntry = (state: Entries, collection: string, slug: string) =>
+export function selectEntry(state: Entries, collection: string, slug: string) {
-  state.getIn(['entities', `${collection}.${slug}`]);
+  return state.getIn(['entities', `${collection}.${slug}`]);
+}
 
-export const selectPublishedSlugs = (state: Entries, collection: string) =>
+export function selectPublishedSlugs(state: Entries, collection: string) {
-  state.getIn(['pages', collection, 'ids'], List<string>());
+  return state.getIn(['pages', collection, 'ids'], List<string>());
+}
 
-const getPublishedEntries = (state: Entries, collectionName: string) => {
+function getPublishedEntries(state: Entries, collectionName: string) {
   const slugs = selectPublishedSlugs(state, collectionName);
   const entries =
     slugs &&
     (slugs.map(slug => selectEntry(state, collectionName, slug as string)) as List<EntryMap>);
   return entries;
-};
+}
 
-export const selectEntries = (state: Entries, collection: Collection) => {
+export function selectEntries(state: Entries, collection: Collection) {
   const collectionName = collection.get('name');
   let entries = getPublishedEntries(state, collectionName);
 
@@ -438,9 +440,9 @@ export const selectEntries = (state: Entries, collection: Collection) => {
   }
 
   return entries;
-};
+}
 
-const getGroup = (entry: EntryMap, selectedGroup: GroupMap) => {
+function getGroup(entry: EntryMap, selectedGroup: GroupMap) {
   const label = selectedGroup.get('label');
   const field = selectedGroup.get('field');
 
@@ -478,9 +480,9 @@ const getGroup = (entry: EntryMap, selectedGroup: GroupMap) => {
     label,
     value: typeof fieldData === 'boolean' ? fieldData : dataAsString,
   };
-};
+}
 
-export const selectGroups = (state: Entries, collection: Collection) => {
+export function selectGroups(state: Entries, collection: Collection) {
   const collectionName = collection.get('name');
   const entries = getPublishedEntries(state, collectionName);
 
@@ -507,37 +509,37 @@ export const selectGroups = (state: Entries, collection: Collection) => {
   });
 
   return groupsArray;
-};
+}
 
-export const selectEntryByPath = (state: Entries, collection: string, path: string) => {
+export function selectEntryByPath(state: Entries, collection: string, path: string) {
   const slugs = selectPublishedSlugs(state, collection);
   const entries =
     slugs && (slugs.map(slug => selectEntry(state, collection, slug as string)) as List<EntryMap>);
 
   return entries && entries.find(e => e?.get('path') === path);
-};
+}
 
-export const selectEntriesLoaded = (state: Entries, collection: string) => {
+export function selectEntriesLoaded(state: Entries, collection: string) {
   return !!state.getIn(['pages', collection]);
-};
+}
 
-export const selectIsFetching = (state: Entries, collection: string) => {
+export function selectIsFetching(state: Entries, collection: string) {
   return state.getIn(['pages', collection, 'isFetching'], false);
-};
+}
 
 const DRAFT_MEDIA_FILES = 'DRAFT_MEDIA_FILES';
 
-const getFileField = (collectionFiles: CollectionFiles, slug: string | undefined) => {
+function getFileField(collectionFiles: CollectionFiles, slug: string | undefined) {
   const file = collectionFiles.find(f => f?.get('name') === slug);
   return file;
-};
+}
 
-const hasCustomFolder = (
+function hasCustomFolder(
   folderKey: 'media_folder' | 'public_folder',
   collection: Collection | null,
   slug: string | undefined,
   field: EntryField | undefined,
-) => {
+) {
   if (!collection) {
     return false;
   }
@@ -558,9 +560,9 @@ const hasCustomFolder = (
   }
 
   return false;
-};
+}
 
-const traverseFields = (
+function traverseFields(
   folderKey: 'media_folder' | 'public_folder',
   config: Config,
   collection: Collection,
@@ -568,7 +570,7 @@ const traverseFields = (
   field: EntryField,
   fields: EntryField[],
   currentFolder: string,
-): string | null => {
+): string | null {
   const matchedField = fields.filter(f => f === field)[0];
   if (matchedField) {
     return folderFormatter(
@@ -632,15 +634,15 @@ const traverseFields = (
   }
 
   return null;
-};
+}
 
-const evaluateFolder = (
+function evaluateFolder(
   folderKey: 'media_folder' | 'public_folder',
   config: Config,
   collection: Collection,
   entryMap: EntryMap | undefined,
   field: EntryField | undefined,
-) => {
+) {
   let currentFolder = config.get(folderKey);
 
   // add identity template if doesn't exist
@@ -723,14 +725,14 @@ const evaluateFolder = (
   }
 
   return currentFolder;
-};
+}
 
-export const selectMediaFolder = (
+export function selectMediaFolder(
   config: Config,
   collection: Collection | null,
   entryMap: EntryMap | undefined,
   field: EntryField | undefined,
-) => {
+) {
   const name = 'media_folder';
   let mediaFolder = config.get(name);
 
@@ -750,15 +752,15 @@ export const selectMediaFolder = (
   }
 
   return trim(mediaFolder, '/');
-};
+}
 
-export const selectMediaFilePath = (
+export function selectMediaFilePath(
   config: Config,
   collection: Collection | null,
   entryMap: EntryMap | undefined,
   mediaPath: string,
   field: EntryField | undefined,
-) => {
+) {
   if (isAbsolutePath(mediaPath)) {
     return mediaPath;
   }
@@ -766,15 +768,15 @@ export const selectMediaFilePath = (
   const mediaFolder = selectMediaFolder(config, collection, entryMap, field);
 
   return join(mediaFolder, basename(mediaPath));
-};
+}
 
-export const selectMediaFilePublicPath = (
+export function selectMediaFilePublicPath(
   config: Config,
   collection: Collection | null,
   mediaPath: string,
   entryMap: EntryMap | undefined,
   field: EntryField | undefined,
-) => {
+) {
   if (isAbsolutePath(mediaPath)) {
     return mediaPath;
   }
@@ -789,12 +791,12 @@ export const selectMediaFilePublicPath = (
   }
 
   return join(publicFolder, basename(mediaPath));
-};
+}
 
-export const selectEditingDraft = (state: EntryDraft) => {
+export function selectEditingDraft(state: EntryDraft) {
   const entry = state.get('entry');
   const workflowDraft = entry && !entry.isEmpty();
   return workflowDraft;
-};
+}
 
 export default entries;

packages/netlify-cms-core/src/reducers/entryDraft.js

@@ -35,7 +35,7 @@ const initialState = Map({
   key: '',
 });
 
-const entryDraftReducer = (state = Map(), action) => {
+function entryDraftReducer(state = Map(), action) {
   switch (action.type) {
     case DRAFT_CREATE_FROM_ENTRY:
       // Existing Entry
@@ -180,9 +180,9 @@ const entryDraftReducer = (state = Map(), action) => {
     default:
       return state;
   }
-};
+}
 
-export const selectCustomPath = (collection, entryDraft) => {
+export function selectCustomPath(collection, entryDraft) {
   if (!selectHasMetaPath(collection)) {
     return;
   }
@@ -192,6 +192,6 @@ export const selectCustomPath = (collection, entryDraft) => {
   const extension = selectFolderEntryExtension(collection);
   const customPath = path && join(collection.get('folder'), path, `${indexFile}.${extension}`);
   return customPath;
-};
+}
 
 export default entryDraftReducer;

packages/netlify-cms-core/src/reducers/globalUI.js

@@ -8,12 +8,14 @@ const LOADING_IGNORE_LIST = [
   'STATUS_FAILURE',
 ];
 
-const ignoreWhenLoading = action => LOADING_IGNORE_LIST.some(type => action.type.includes(type));
+function ignoreWhenLoading(action) {
+  return LOADING_IGNORE_LIST.some(type => action.type.includes(type));
+}
 
-/*
+/**
  * Reducer for some global UI state that we want to share between components
- * */
+ */
-const globalUI = (state = Map({ isFetching: false, useOpenAuthoring: false }), action) => {
+function globalUI(state = Map({ isFetching: false, useOpenAuthoring: false }), action) {
   // Generic, global loading indicator
   if (!ignoreWhenLoading(action) && action.type.includes('REQUEST')) {
     return state.set('isFetching', true);
@@ -26,6 +28,6 @@ const globalUI = (state = Map({ isFetching: false, useOpenAuthoring: false }), a
     return state.set('useOpenAuthoring', true);
   }
   return state;
-};
+}
 
 export default globalUI;

packages/netlify-cms-core/src/reducers/index.ts

@@ -37,16 +37,19 @@ export default reducers;
 /*
  * Selectors
  */
-export const selectEntry = (state: State, collection: string, slug: string) =>
+export function selectEntry(state: State, collection: string, slug: string) {
-  fromEntries.selectEntry(state.entries, collection, slug);
+  return fromEntries.selectEntry(state.entries, collection, slug);
+}
 
-export const selectEntries = (state: State, collection: Collection) =>
+export function selectEntries(state: State, collection: Collection) {
-  fromEntries.selectEntries(state.entries, collection);
+  return fromEntries.selectEntries(state.entries, collection);
+}
 
-export const selectPublishedSlugs = (state: State, collection: string) =>
+export function selectPublishedSlugs(state: State, collection: string) {
-  fromEntries.selectPublishedSlugs(state.entries, collection);
+  return fromEntries.selectPublishedSlugs(state.entries, collection);
+}
 
-export const selectSearchedEntries = (state: State, availableCollections: string[]) => {
+export function selectSearchedEntries(state: State, availableCollections: string[]) {
   const searchItems = state.search.get('entryIds');
   // only return search results for actually available collections
   return (
@@ -55,19 +58,24 @@ export const selectSearchedEntries = (state: State, availableCollections: string
       .filter(({ collection }) => availableCollections.indexOf(collection) !== -1)
       .map(({ collection, slug }) => fromEntries.selectEntry(state.entries, collection, slug))
   );
-};
+}
 
-export const selectDeployPreview = (state: State, collection: string, slug: string) =>
+export function selectDeployPreview(state: State, collection: string, slug: string) {
-  fromDeploys.selectDeployPreview(state.deploys, collection, slug);
+  return fromDeploys.selectDeployPreview(state.deploys, collection, slug);
+}
 
-export const selectUnpublishedEntry = (state: State, collection: string, slug: string) =>
+export function selectUnpublishedEntry(state: State, collection: string, slug: string) {
-  fromEditorialWorkflow.selectUnpublishedEntry(state.editorialWorkflow, collection, slug);
+  return fromEditorialWorkflow.selectUnpublishedEntry(state.editorialWorkflow, collection, slug);
+}
 
-export const selectUnpublishedEntriesByStatus = (state: State, status: Status) =>
+export function selectUnpublishedEntriesByStatus(state: State, status: Status) {
-  fromEditorialWorkflow.selectUnpublishedEntriesByStatus(state.editorialWorkflow, status);
+  return fromEditorialWorkflow.selectUnpublishedEntriesByStatus(state.editorialWorkflow, status);
+}
 
-export const selectUnpublishedSlugs = (state: State, collection: string) =>
+export function selectUnpublishedSlugs(state: State, collection: string) {
-  fromEditorialWorkflow.selectUnpublishedSlugs(state.editorialWorkflow, collection);
+  return fromEditorialWorkflow.selectUnpublishedSlugs(state.editorialWorkflow, collection);
+}
 
-export const selectIntegration = (state: State, collection: string | null, hook: string) =>
+export function selectIntegration(state: State, collection: string | null, hook: string) {
-  fromIntegrations.selectIntegration(state.integrations, collection, hook);
+  return fromIntegrations.selectIntegration(state.integrations, collection, hook);
+}

packages/netlify-cms-core/src/reducers/integrations.ts

@@ -7,7 +7,7 @@ interface Acc {
   hooks: Record<string, string | Record<string, string>>;
 }
 
-export const getIntegrations = (config: Config) => {
+export function getIntegrations(config: Config) {
   const integrations: Integration[] = config.get('integrations', List()).toJS() || [];
   const newState = integrations.reduce(
     (acc, integration) => {
@@ -38,9 +38,9 @@ export const getIntegrations = (config: Config) => {
     { providers: {}, hooks: {} } as Acc,
   );
   return fromJS(newState);
-};
+}
 
-const integrations = (state = null, action: IntegrationsAction): Integrations | null => {
+function integrations(state = null, action: IntegrationsAction): Integrations | null {
   switch (action.type) {
     case CONFIG_SUCCESS: {
       return getIntegrations(action.payload);
@@ -48,11 +48,12 @@ const integrations = (state = null, action: IntegrationsAction): Integrations |
     default:
       return state;
   }
-};
+}
 
-export const selectIntegration = (state: Integrations, collection: string | null, hook: string) =>
+export function selectIntegration(state: Integrations, collection: string | null, hook: string) {
-  collection
+  return collection
     ? state.getIn(['hooks', collection, hook], false)
     : state.getIn(['hooks', hook], false);
+}
 
 export default integrations;

packages/netlify-cms-core/src/reducers/mediaLibrary.ts

@@ -51,7 +51,7 @@ const defaultState: {
   config: Map(),
 };
 
-const mediaLibrary = (state = Map(defaultState), action: MediaLibraryAction) => {
+function mediaLibrary(state = Map(defaultState), action: MediaLibraryAction) {
   switch (action.type) {
     case MEDIA_LIBRARY_CREATE:
       return state.withMutations(map => {
@@ -213,7 +213,7 @@ const mediaLibrary = (state = Map(defaultState), action: MediaLibraryAction) =>
     default:
       return state;
   }
-};
+}
 
 export function selectMediaFiles(state: State, field?: EntryField) {
   const { mediaLibrary, entryDraft } = state;

packages/netlify-cms-core/src/reducers/medias.ts

@@ -57,7 +57,8 @@ const medias = produce((state: Medias, action: MediasAction) => {
   }
 }, defaultState);
 
-export const selectIsLoadingAsset = (state: Medias) =>
+export function selectIsLoadingAsset(state: Medias) {
-  Object.values(state).some(state => state.isLoading);
+  return Object.values(state).some(state => state.isLoading);
+}
 
 export default medias;

packages/netlify-cms-core/src/reducers/search.js

@@ -23,7 +23,7 @@ const defaultState = Map({
   queryHits: Map({}),
 });
 
-const entries = (state = defaultState, action) => {
+function entries(state = defaultState, action) {
   switch (action.type) {
     case SEARCH_CLEAR:
       return defaultState;
@@ -84,6 +84,6 @@ const entries = (state = defaultState, action) => {
     default:
       return state;
   }
-};
+}
 
 export default entries;

packages/netlify-cms-core/src/redux/middleware/waitUntilAction.ts

@@ -21,6 +21,7 @@ interface WaitAction extends WaitActionArgs {
   type: typeof WAIT_UNTIL_ACTION;
 }
 
+// eslint-disable-next-line func-style
 export const waitUntilAction: Middleware<{}, State, Dispatch> = ({
   dispatch,
   getState,
@@ -50,7 +51,7 @@ export const waitUntilAction: Middleware<{}, State, Dispatch> = ({
     }
   }
 
-  return (next: Dispatch) => (action: AnyAction): null | AnyAction => {
+  return (next: Dispatch<AnyAction>) => (action: AnyAction): null | AnyAction => {
     if (action.type === WAIT_UNTIL_ACTION) {
       pending.push(action as WaitAction);
       return null;

packages/netlify-cms-core/src/routing/history.ts

@@ -2,11 +2,16 @@ import { createHashHistory } from 'history';
 
 const history = createHashHistory();
 
-export const navigateToCollection = (collectionName: string) =>
+export function navigateToCollection(collectionName: string) {
-  history.push(`/collections/${collectionName}`);
+  return history.push(`/collections/${collectionName}`);
-export const navigateToNewEntry = (collectionName: string) =>
+}
-  history.replace(`/collections/${collectionName}/new`);
+
-export const navigateToEntry = (collectionName: string, slug: string) =>
+export function navigateToNewEntry(collectionName: string) {
-  history.replace(`/collections/${collectionName}/entries/${slug}`);
+  return history.replace(`/collections/${collectionName}/new`);
+}
+
+export function navigateToEntry(collectionName: string, slug: string) {
+  return history.replace(`/collections/${collectionName}/entries/${slug}`);
+}
 
 export default history;

packages/netlify-cms-core/src/valueObjects/EditorComponent.js

@@ -2,7 +2,10 @@ import { fromJS } from 'immutable';
 import { isFunction } from 'lodash';
 
 const catchesNothing = /.^/;
-const bind = fn => isFunction(fn) && fn.bind(null);
+
+function bind(fn) {
+  return isFunction(fn) && fn.bind(null);
+}
 
 export default function createEditorComponent(config) {
   const {

packages/netlify-cms-core/webpack.config.js

@@ -8,13 +8,13 @@ const versionPlugin = new webpack.DefinePlugin({
   NETLIFY_CMS_CORE_VERSION: JSON.stringify(`${pkg.version}${isProduction ? '' : '-dev'}`),
 });
 
-const configs = () => {
+function configs() {
   return getConfig().map(config => {
     return {
       ...config,
       plugins: [...config.plugins, versionPlugin],
     };
   });
-};
+}
 
 module.exports = configs();

packages/netlify-cms-editor-component-image/src/__tests__/index.spec.js

@@ -1,6 +1,9 @@
 import component from '../index';
 
-const getAsset = path => path;
+function getAsset(path) {
+  return path;
+}
+
 const image = '/image';
 const alt = 'alt';
 const title = 'title';

packages/netlify-cms-lib-util/src/API.ts

@@ -38,11 +38,11 @@ class RateLimitError extends Error {
   }
 }
 
-export const requestWithBackoff = async (
+export async function requestWithBackoff(
   api: API,
   req: ApiRequest,
   attempt = 1,
-): Promise<Response> => {
+): Promise<Response> {
   if (api.rateLimiter) {
     await api.rateLimiter.acquire();
   }
@@ -92,14 +92,14 @@ export const requestWithBackoff = async (
       return requestWithBackoff(api, req, attempt + 1);
     }
   }
-};
+}
 
-export const readFile = async (
+export async function readFile(
   id: string | null | undefined,
   fetchContent: () => Promise<string | Blob>,
   localForage: LocalForage,
   isText: boolean,
-) => {
+) {
   const key = id ? (isText ? `gh.${id}` : `gh.${id}.blob`) : null;
   const cached = key ? await localForage.getItem<string | Blob>(key) : null;
   if (cached) {
@@ -111,20 +111,22 @@ export const readFile = async (
     await localForage.setItem(key, content);
   }
   return content;
-};
+}
 
 export type FileMetadata = {
   author: string;
   updatedOn: string;
 };
 
-const getFileMetadataKey = (id: string) => `gh.${id}.meta`;
+function getFileMetadataKey(id: string) {
+  return `gh.${id}.meta`;
+}
 
-export const readFileMetadata = async (
+export async function readFileMetadata(
   id: string | null | undefined,
   fetchMetadata: () => Promise<FileMetadata>,
   localForage: LocalForage,
-) => {
+) {
   const key = id ? getFileMetadataKey(id) : null;
   const cached = key && (await localForage.getItem<FileMetadata>(key));
   if (cached) {
@@ -136,7 +138,7 @@ export const readFileMetadata = async (
     await localForage.setItem<FileMetadata>(key, metadata);
   }
   return metadata;
-};
+}
 
 /**
  * Keywords for inferring a status that will provide a deploy preview URL.
@@ -148,12 +150,12 @@ const PREVIEW_CONTEXT_KEYWORDS = ['deploy'];
  * deploy preview. Checks for an exact match against `previewContext` if given,
  * otherwise checks for inclusion of a value from `PREVIEW_CONTEXT_KEYWORDS`.
  */
-export const isPreviewContext = (context: string, previewContext: string) => {
+export function isPreviewContext(context: string, previewContext: string) {
   if (previewContext) {
     return context === previewContext;
   }
   return PREVIEW_CONTEXT_KEYWORDS.some(keyword => context.includes(keyword));
-};
+}
 
 export enum PreviewState {
   Other = 'other',
@@ -164,20 +166,20 @@ export enum PreviewState {
  * Retrieve a deploy preview URL from an array of statuses. By default, a
  * matching status is inferred via `isPreviewContext`.
  */
-export const getPreviewStatus = (
+export function getPreviewStatus(
   statuses: {
     context: string;
     target_url: string;
     state: PreviewState;
   }[],
   previewContext: string,
-) => {
+) {
   return statuses.find(({ context }) => {
     return isPreviewContext(context, previewContext);
   });
-};
+}
 
-const getConflictingBranches = (branchName: string) => {
+function getConflictingBranches(branchName: string) {
   // for cms/posts/post-1, conflicting branches are cms/posts, cms
   const parts = branchName.split('/');
   parts.pop();
@@ -188,13 +190,13 @@ const getConflictingBranches = (branchName: string) => {
   }, [] as string[]);
 
   return conflictingBranches;
-};
+}
 
-export const throwOnConflictingBranches = async (
+export async function throwOnConflictingBranches(
   branchName: string,
   getBranch: (name: string) => Promise<{ name: string }>,
   apiName: string,
-) => {
+) {
   const possibleConflictingBranches = getConflictingBranches(branchName);
 
   const conflictingBranches = await Promise.all(
@@ -213,4 +215,4 @@ export const throwOnConflictingBranches = async (
       apiName,
     );
   }
-};
+}

packages/netlify-cms-lib-util/src/APIUtils.ts

@@ -3,27 +3,36 @@ export const DEFAULT_PR_BODY = 'Automatically generated by Netlify CMS';
 export const MERGE_COMMIT_MESSAGE = 'Automatically generated. Merged on Netlify CMS.';
 
 const DEFAULT_NETLIFY_CMS_LABEL_PREFIX = 'netlify-cms/';
-const getLabelPrefix = (labelPrefix: string) => labelPrefix || DEFAULT_NETLIFY_CMS_LABEL_PREFIX;
 
-export const isCMSLabel = (label: string, labelPrefix: string) =>
+function getLabelPrefix(labelPrefix: string) {
-  label.startsWith(getLabelPrefix(labelPrefix));
+  return labelPrefix || DEFAULT_NETLIFY_CMS_LABEL_PREFIX;
-export const labelToStatus = (label: string, labelPrefix: string) =>
+}
-  label.substr(getLabelPrefix(labelPrefix).length);
-export const statusToLabel = (status: string, labelPrefix: string) =>
-  `${getLabelPrefix(labelPrefix)}${status}`;
 
-export const generateContentKey = (collectionName: string, slug: string) =>
+export function isCMSLabel(label: string, labelPrefix: string) {
-  `${collectionName}/${slug}`;
+  return label.startsWith(getLabelPrefix(labelPrefix));
+}
 
-export const parseContentKey = (contentKey: string) => {
+export function labelToStatus(label: string, labelPrefix: string) {
+  return label.substr(getLabelPrefix(labelPrefix).length);
+}
+
+export function statusToLabel(status: string, labelPrefix: string) {
+  return `${getLabelPrefix(labelPrefix)}${status}`;
+}
+
+export function generateContentKey(collectionName: string, slug: string) {
+  return `${collectionName}/${slug}`;
+}
+
+export function parseContentKey(contentKey: string) {
   const index = contentKey.indexOf('/');
   return { collection: contentKey.substr(0, index), slug: contentKey.substr(index + 1) };
-};
+}
 
-export const contentKeyFromBranch = (branch: string) => {
+export function contentKeyFromBranch(branch: string) {
   return branch.substring(`${CMS_BRANCH_PREFIX}/`.length);
-};
+}
 
-export const branchFromContentKey = (contentKey: string) => {
+export function branchFromContentKey(contentKey: string) {
   return `${CMS_BRANCH_PREFIX}/${contentKey}`;
-};
+}

packages/netlify-cms-lib-util/src/Cursor.ts

@@ -27,7 +27,7 @@ export type CursorStore = {
 
 type ActionHandler = (action: string) => unknown;
 
-const jsToMap = (obj: {}) => {
+function jsToMap(obj: {}) {
   if (obj === undefined) {
     return Map();
   }
@@ -36,7 +36,7 @@ const jsToMap = (obj: {}) => {
     throw new Error('Object must be equivalent to a Map.');
   }
   return immutableObj;
-};
+}
 
 const knownMetaKeys = Set([
   'index',
@@ -49,8 +49,10 @@ const knownMetaKeys = Set([
   'folder',
   'depth',
 ]);
-const filterUnknownMetaKeys = (meta: Map<string, string>) =>
+
-  meta.filter((_v, k) => knownMetaKeys.has(k as string));
+function filterUnknownMetaKeys(meta: Map<string, string>) {
+  return meta.filter((_v, k) => knownMetaKeys.has(k as string));
+}
 
 /*
   createCursorMap takes one of three signatures:
@@ -58,7 +60,7 @@ const filterUnknownMetaKeys = (meta: Map<string, string>) =>
   - (cursorMap: <object/Map with optional actions, data, and meta keys>) -> cursor
   - (actions: <array/List>, data: <object/Map>, meta: <optional object/Map>) -> cursor
 */
-const createCursorStore = (...args: {}[]) => {
+function createCursorStore(...args: {}[]) {
   const { actions, data, meta } =
     args.length === 1
       ? jsToMap(args[0]).toObject()
@@ -71,15 +73,18 @@ const createCursorStore = (...args: {}[]) => {
     data: jsToMap(data),
     meta: jsToMap(meta).update(filterUnknownMetaKeys),
   }) as CursorStore;
-};
+}
 
-const hasAction = (store: CursorStore, action: string) => store.hasIn(['actions', action]);
+function hasAction(store: CursorStore, action: string) {
+  return store.hasIn(['actions', action]);
+}
 
-const getActionHandlers = (store: CursorStore, handler: ActionHandler) =>
+function getActionHandlers(store: CursorStore, handler: ActionHandler) {
-  store
+  return store
     .get('actions', Set<string>())
     .toMap()
     .map(action => handler(action as string));
+}
 
 // The cursor logic is entirely functional, so this class simply
 // provides a chainable interface

packages/netlify-cms-lib-util/src/__tests__/backendUtil.spec.js

@@ -21,17 +21,20 @@ describe('parseLinkHeader', () => {
 });
 
 describe('getAllResponses', () => {
-  const generatePulls = length => {
+  function generatePulls(length) {
     return Array.from({ length }, (_, id) => {
       return { id: id + 1, number: `134${id}`, state: 'open' };
     });
-  };
+  }
 
   function createLinkHeaders({ page, pageCount }) {
     const pageNum = parseInt(page, 10);
     const pageCountNum = parseInt(pageCount, 10);
     const url = 'https://api.github.com/pulls';
-    const link = linkPage => `<${url}?page=${linkPage}>`;
+
+    function link(linkPage) {
+      return `<${url}?page=${linkPage}>`;
+    }
 
     const linkHeader = oneLine`
       ${pageNum === 1 ? '' : `${link(1)}; rel="first",`}

packages/netlify-cms-lib-util/src/asyncLock.ts

@@ -2,10 +2,10 @@ import semaphore from 'semaphore';
 
 export type AsyncLock = { release: () => void; acquire: () => Promise<boolean> };
 
-export const asyncLock = (): AsyncLock => {
+export function asyncLock(): AsyncLock {
   let lock = semaphore(1);
 
-  const acquire = (timeout = 15000) => {
+  function acquire(timeout = 15000) {
     const promise = new Promise<boolean>(resolve => {
       // this makes sure a caller doesn't gets stuck forever awaiting on the lock
       const timeoutId = setTimeout(() => {
@@ -21,9 +21,9 @@ export const asyncLock = (): AsyncLock => {
     });
 
     return promise;
-  };
+  }
 
-  const release = () => {
+  function release() {
     try {
       // suppress too many calls to leave error
       lock.leave();
@@ -37,7 +37,7 @@ export const asyncLock = (): AsyncLock => {
         lock = semaphore(1);
       }
     }
-  };
+  }
 
   return { acquire, release };
-};
+}