refactor: monorepo setup with lerna (#243)

packages/core/test/mockFetch.ts

@@ -0,0 +1,90 @@
+export const createMockRequest = <T>(
+  status: number,
+  data: {
+    json?: T;
+    text?: string;
+  },
+  options: {
+    contentType?: string;
+    headers?: Record<string, string>;
+  } = {},
+): Response => {
+  const { contentType = 'application/json', headers = {} } = options;
+
+  const finalHeaders = (function () {
+    const data: Record<string, string> = headers;
+
+    return {
+      get: (key: string) => {
+        return data[key];
+      },
+      set: (key: string, value: string) => {
+        data[key] = value;
+      },
+    };
+  })();
+
+  finalHeaders.set('Content-Type', contentType);
+
+  return {
+    status,
+    ok: status < 400,
+    headers: finalHeaders,
+    json: () => Promise.resolve(data.json),
+    text: () => Promise.resolve(data.text),
+  } as Response;
+};
+
+export interface MockFetch {
+  baseUrl: string;
+  mocks: Record<string, Response>;
+  when: (url: string) => {
+    reply: <T>(
+      status: number,
+      data: {
+        json?: T;
+        text?: string;
+      },
+      options?: {
+        contentType?: string;
+        headers?: Record<string, string>;
+      },
+    ) => void;
+  };
+  reset: () => void;
+}
+
+const mockFetch = (baseUrl: string): MockFetch => {
+  const mockedFetch: MockFetch = {
+    baseUrl,
+    mocks: {},
+    when(this: MockFetch, url: string) {
+      return {
+        reply: <T>(
+          status: number,
+          data: {
+            json?: T;
+            text?: string;
+          },
+          options?: {
+            contentType?: string;
+            headers?: Record<string, string>;
+          },
+        ) => {
+          this.mocks[`${baseUrl}${url}`] = createMockRequest(status, data, options);
+        },
+      };
+    },
+    reset(this: MockFetch) {
+      this.mocks = {};
+    },
+  };
+
+  global.fetch = jest.fn().mockImplementation((url: string) => {
+    return Promise.resolve(mockedFetch.mocks[url.split('?')[0]]);
+  });
+
+  return mockedFetch;
+};
+
+export default mockFetch;