From 834be962c5b6b1876e8984db7115fe4eceab240d Mon Sep 17 00:00:00 2001
From: Kacper Wiszczuk <kacperwiszczuk@gmail.com>
Date: Wed, 3 Jul 2019 16:30:23 +0200
Subject: [PATCH 01/11] imp: standarize fetch in CLI

---
 .../init/__tests__/templateName.test.js       | 18 +++---
 .../cli/src/commands/init/templateName.js     | 10 +++-
 .../upgrade/__tests__/upgrade.test.js         | 28 +++++----
 packages/cli/src/commands/upgrade/upgrade.js  | 12 +++-
 .../tools/releaseChecker/getLatestRelease.js  | 57 ++++++++++---------
 packages/tools/src/fetch.ts                   | 12 ++++
 packages/tools/src/index.ts                   |  1 +
 packages/tools/src/isPackagerRunning.ts       |  2 +-
 8 files changed, 88 insertions(+), 52 deletions(-)
 create mode 100644 packages/tools/src/fetch.ts

diff --git a/packages/cli/src/commands/init/__tests__/templateName.test.js b/packages/cli/src/commands/init/__tests__/templateName.test.js
index db972581b..34dc7fa35 100644
--- a/packages/cli/src/commands/init/__tests__/templateName.test.js
+++ b/packages/cli/src/commands/init/__tests__/templateName.test.js
@@ -1,12 +1,18 @@
 // @flow
 import {processTemplateName} from '../templateName';
-import {fetch} from '../../../tools/fetch';
+import {fetch} from '@react-native-community/cli-tools';
 
-jest.mock('../../../tools/fetch', () => ({fetch: jest.fn()}));
+jest.mock('@react-native-community/cli-tools', () => ({fetch: jest.fn()}));
 
 const RN_NPM_PACKAGE = 'react-native';
 const ABS_RN_PATH = '/path/to/react-native';
 
+const mockFetch = (value: any, status: number) => {
+  (fetch: any).mockImplementation(() =>
+    Promise.resolve({json: () => Promise.resolve(value), status}),
+  );
+};
+
 test('supports file protocol with absolute path', async () => {
   jest.mock(
     `${ABS_RN_PATH}/package.json`,
@@ -23,9 +29,7 @@ test('supports file protocol with absolute path', async () => {
 
 test('supports shorthand templates', async () => {
   const templateName = 'typescript';
-  (fetch: any).mockImplementationOnce(() => {
-    return Promise.resolve(`{"name": "react-native-template-${templateName}"}`);
-  });
+  mockFetch({name: 'react-native-template-${templateName}'}, 200);
   expect(await processTemplateName(templateName)).toEqual({
     uri: `react-native-template-${templateName}`,
     name: `react-native-template-${templateName}`,
@@ -34,9 +38,7 @@ test('supports shorthand templates', async () => {
 
 test('supports not-found shorthand templates', async () => {
   const templateName = 'typescriptz';
-  (fetch: any).mockImplementationOnce(() => {
-    return Promise.resolve('Not found');
-  });
+  mockFetch('Not found', 200);
   expect(await processTemplateName(templateName)).toEqual({
     uri: templateName,
     name: templateName,
diff --git a/packages/cli/src/commands/init/templateName.js b/packages/cli/src/commands/init/templateName.js
index d2b8b7e98..901f6d05a 100644
--- a/packages/cli/src/commands/init/templateName.js
+++ b/packages/cli/src/commands/init/templateName.js
@@ -1,7 +1,7 @@
 // @flow
 import path from 'path';
 import {URL} from 'url';
-import {fetch} from '../../tools/fetch';
+import {fetch} from '@react-native-community/cli-tools';
 
 const FILE_PROTOCOL = /file:/;
 const HTTP_PROTOCOL = /https?:/;
@@ -81,7 +81,13 @@ async function tryTemplateShorthand(templateName: string) {
       `https://registry.yarnpkg.com/${reactNativeTemplatePackage}/latest`,
     );
 
-    if (JSON.parse(response).name) {
+    if (response.status < 200 || response.status > 299) {
+      throw new Error(`Failed to load page, status code: ${response.status}`);
+    }
+
+    const body = await response.json();
+
+    if (body.name) {
       return reactNativeTemplatePackage;
     }
   } catch (e) {
diff --git a/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js b/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
index 9f5e11826..4a4857722 100644
--- a/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
+++ b/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
@@ -5,7 +5,7 @@ import fs from 'fs';
 import snapshotDiff from 'snapshot-diff';
 import stripAnsi from 'strip-ansi';
 import upgrade from '../upgrade';
-import {fetch} from '../../../tools/fetch';
+import {fetch} from '@react-native-community/cli-tools';
 import logger from '../../../tools/logger';
 import loadConfig from '../../../tools/config';
 import merge from '../../../tools/merge';
@@ -43,11 +43,11 @@ jest.mock('../../../tools/packageManager', () => ({
     mockPushLog('$ yarn add', ...args);
   },
 }));
-jest.mock('../../../tools/fetch', () => ({
-  fetch: jest.fn(() => Promise.resolve('patch')),
-}));
 jest.mock('@react-native-community/cli-tools', () => ({
   ...jest.requireActual('@react-native-community/cli-tools'),
+  fetch: jest.fn(() =>
+    Promise.resolve({json: () => Promise.resolve('patch'), status: 200}),
+  ),
   logger: {
     info: jest.fn((...args) => mockPushLog('info', args)),
     error: jest.fn((...args) => mockPushLog('error', args)),
@@ -58,6 +58,12 @@ jest.mock('@react-native-community/cli-tools', () => ({
   },
 }));
 
+const mockFetch = (value, status) => {
+  (fetch: any).mockImplementation(() =>
+    Promise.resolve({json: () => Promise.resolve(value), status}),
+  );
+};
+
 const mockExecaDefault = (command, args) => {
   mockPushLog('$', 'execa', command, args);
   if (command === 'npm' && args[3] === '--json') {
@@ -121,7 +127,7 @@ test('uses latest version of react-native when none passed', async () => {
 }, 60000);
 
 test('applies patch in current working directory when nested', async () => {
-  (fetch: any).mockImplementation(() => Promise.resolve(samplePatch));
+  mockFetch(samplePatch, 200);
   (execa: any).mockImplementation(mockExecaNested);
   const config = {...ctx, root: '/project/root/NestedApp'};
   await upgrade.func([newVersion], config, opts);
@@ -162,7 +168,7 @@ test('warns when dependency upgrade version is in semver range', async () => {
 }, 60000);
 
 test('fetches empty patch and installs deps', async () => {
-  (fetch: any).mockImplementation(() => Promise.resolve(''));
+  mockFetch('', 200);
   await upgrade.func([newVersion], ctx, opts);
   expect(flushOutput()).toMatchInlineSnapshot(`
     "info Fetching diff between v0.57.8 and v0.58.4...
@@ -178,7 +184,9 @@ test('fetches empty patch and installs deps', async () => {
 }, 60000);
 
 test('fetches regular patch, adds remote, applies patch, installs deps, removes remote,', async () => {
-  (fetch: any).mockImplementation(() => Promise.resolve(samplePatch));
+  (fetch: any).mockImplementation(() =>
+    Promise.resolve({json: () => Promise.resolve(samplePatch), status: 200}),
+  );
   await upgrade.func(
     [newVersion],
     merge(ctx, {
@@ -217,7 +225,7 @@ test('fetches regular patch, adds remote, applies patch, installs deps, removes
   );
 }, 60000);
 test('fetches regular patch, adds remote, applies patch, installs deps, removes remote when updated from nested directory', async () => {
-  (fetch: any).mockImplementation(() => Promise.resolve(samplePatch));
+  mockFetch(samplePatch, 200);
   (execa: any).mockImplementation(mockExecaNested);
   const config = {...ctx, root: '/project/root/NestedApp'};
   await upgrade.func([newVersion], config, opts);
@@ -242,7 +250,7 @@ test('fetches regular patch, adds remote, applies patch, installs deps, removes
   `);
 }, 60000);
 test('cleans up if patching fails,', async () => {
-  (fetch: any).mockImplementation(() => Promise.resolve(samplePatch));
+  mockFetch(samplePatch, 200);
   (execa: any).mockImplementation((command, args) => {
     mockPushLog('$', 'execa', command, args);
     if (command === 'npm' && args[3] === '--json') {
@@ -296,7 +304,7 @@ test('cleans up if patching fails,', async () => {
   `);
 }, 60000);
 test('works with --name-ios and --name-android', async () => {
-  (fetch: any).mockImplementation(() => Promise.resolve(samplePatch));
+  mockFetch(samplePatch, 200);
   await upgrade.func(
     [newVersion],
     merge(ctx, {
diff --git a/packages/cli/src/commands/upgrade/upgrade.js b/packages/cli/src/commands/upgrade/upgrade.js
index d3cbb5085..4e0818d8c 100644
--- a/packages/cli/src/commands/upgrade/upgrade.js
+++ b/packages/cli/src/commands/upgrade/upgrade.js
@@ -5,9 +5,8 @@ import chalk from 'chalk';
 import semver from 'semver';
 import execa from 'execa';
 import type {ConfigT} from 'types';
-import {logger, CLIError} from '@react-native-community/cli-tools';
+import {logger, CLIError, fetch} from '@react-native-community/cli-tools';
 import * as PackageManager from '../../tools/packageManager';
-import {fetch} from '../../tools/fetch';
 import legacyUpgrade from './legacyUpgrade';
 
 type FlagsT = {
@@ -46,7 +45,14 @@ const getPatch = async (currentVersion, newVersion, config) => {
   logger.info(`Fetching diff between v${currentVersion} and v${newVersion}...`);
 
   try {
-    patch = await fetch(`${rawDiffUrl}/${currentVersion}..${newVersion}.diff`);
+    const response = await fetch(
+      `${rawDiffUrl}/${currentVersion}..${newVersion}.diff`,
+    );
+
+    if (response.status < 200 || response.status > 299) {
+      throw new Error(`Failed to load page, status code: ${response.status}`);
+    }
+    patch = await response.json();
   } catch (error) {
     logger.error(
       `Failed to fetch diff for react-native@${newVersion}. Maybe it's not released yet?`,
diff --git a/packages/cli/src/tools/releaseChecker/getLatestRelease.js b/packages/cli/src/tools/releaseChecker/getLatestRelease.js
index 7f41a2304..03b4d996e 100644
--- a/packages/cli/src/tools/releaseChecker/getLatestRelease.js
+++ b/packages/cli/src/tools/releaseChecker/getLatestRelease.js
@@ -1,10 +1,10 @@
 /**
  * @flow
  */
-import https from 'https';
 import semver from 'semver';
 import logger from '../logger';
 import cacheManager from './releaseCacheManager';
+import {fetch} from '@react-native-community/cli-tools';
 
 export type Release = {
   version: string,
@@ -81,11 +81,12 @@ async function getLatestRnDiffPurgeVersion(name: string, eTag: ?string) {
     options.headers['If-None-Match'] = eTag;
   }
 
-  const response = await httpsGet(options);
+  const response = await fetch(options);
 
   // Remote is newer.
-  if (response.statusCode === 200) {
-    const latestVersion = JSON.parse(response.body)[0].name.substring(8);
+  if (response.status === 200) {
+    const body: Array<any> = await response.json();
+    const latestVersion = body[0].name.substring(8);
 
     // Update cache only if newer release is stable.
     if (!semver.prerelease(latestVersion)) {
@@ -114,27 +115,27 @@ type Headers = {
   [header: string]: mixed,
 };
 
-function httpsGet(options) {
-  return new Promise((resolve, reject) => {
-    https
-      .get(options, result => {
-        let body = '';
-
-        result.setEncoding('utf8');
-        result.on('data', data => {
-          body += data;
-        });
-
-        result.on('end', () => {
-          resolve({
-            body,
-            eTag: result.headers.etag,
-            statusCode: result.statusCode,
-          });
-        });
-
-        result.on('error', error => reject(error));
-      })
-      .on('error', error => reject(error));
-  });
-}
+// function httpsGet(options) {
+//   return new Promise((resolve, reject) => {
+//     https
+//       .get(options, result => {
+//         let body = '';
+
+//         result.setEncoding('utf8');
+//         result.on('data', data => {
+//           body += data;
+//         });
+
+//         result.on('end', () => {
+//           resolve({
+//             body,
+//             eTag: result.headers.etag,
+//             statusCode: result.statusCode,
+//           });
+//         });
+
+//         result.on('error', error => reject(error));
+//       })
+//       .on('error', error => reject(error));
+//   });
+// }
diff --git a/packages/tools/src/fetch.ts b/packages/tools/src/fetch.ts
new file mode 100644
index 000000000..1f9e7bc56
--- /dev/null
+++ b/packages/tools/src/fetch.ts
@@ -0,0 +1,12 @@
+import nodeFetch, {
+  RequestInit as FetchOptions,
+  Response,
+  Request,
+} from 'node-fetch';
+
+export default function fetch(
+  url: string | Request,
+  options?: FetchOptions,
+): Promise<Response> {
+  return nodeFetch(url, options);
+}
diff --git a/packages/tools/src/index.ts b/packages/tools/src/index.ts
index d99e20bf0..0a6f4fafa 100644
--- a/packages/tools/src/index.ts
+++ b/packages/tools/src/index.ts
@@ -2,5 +2,6 @@ export {default as logger} from './logger';
 export {default as groupFilesByType} from './groupFilesByType';
 export {default as isPackagerRunning} from './isPackagerRunning';
 export {default as getDefaultUserTerminal} from './getDefaultUserTerminal';
+export {default as fetch} from './fetch';
 
 export * from './errors';
diff --git a/packages/tools/src/isPackagerRunning.ts b/packages/tools/src/isPackagerRunning.ts
index 11b276368..b2b888005 100644
--- a/packages/tools/src/isPackagerRunning.ts
+++ b/packages/tools/src/isPackagerRunning.ts
@@ -6,7 +6,7 @@
  *
  */
 
-import fetch from 'node-fetch';
+import fetch from './fetch';
 
 /**
  * Indicates whether or not the packager is running. It returns a promise that

From 693573c2a67e0fe7565e2a221a5f6333f65958f4 Mon Sep 17 00:00:00 2001
From: Kacper Wiszczuk <kacperwiszczuk@gmail.com>
Date: Wed, 3 Jul 2019 16:34:47 +0200
Subject: [PATCH 02/11] imp: remove commented out function

---
 .../tools/releaseChecker/getLatestRelease.js  | 25 -------------------
 1 file changed, 25 deletions(-)

diff --git a/packages/cli/src/tools/releaseChecker/getLatestRelease.js b/packages/cli/src/tools/releaseChecker/getLatestRelease.js
index 03b4d996e..d4cf005b7 100644
--- a/packages/cli/src/tools/releaseChecker/getLatestRelease.js
+++ b/packages/cli/src/tools/releaseChecker/getLatestRelease.js
@@ -114,28 +114,3 @@ type Headers = {
   'User-Agent': mixed,
   [header: string]: mixed,
 };
-
-// function httpsGet(options) {
-//   return new Promise((resolve, reject) => {
-//     https
-//       .get(options, result => {
-//         let body = '';
-
-//         result.setEncoding('utf8');
-//         result.on('data', data => {
-//           body += data;
-//         });
-
-//         result.on('end', () => {
-//           resolve({
-//             body,
-//             eTag: result.headers.etag,
-//             statusCode: result.statusCode,
-//           });
-//         });
-
-//         result.on('error', error => reject(error));
-//       })
-//       .on('error', error => reject(error));
-//   });
-// }

From 4550995eaeed5750fef28f568fe797ff5285a03d Mon Sep 17 00:00:00 2001
From: Kacper Wiszczuk <kacperwiszczuk@gmail.com>
Date: Tue, 16 Jul 2019 17:36:04 +0200
Subject: [PATCH 03/11] Change fetch a little bit

---
 .../init/__tests__/templateName.test.js       |  2 --
 .../upgrade/__tests__/upgrade.test.js         | 12 +++--------
 packages/cli/src/commands/upgrade/upgrade.js  |  8 +++----
 .../tools/releaseChecker/getLatestRelease.js  | 14 +++++++------
 packages/tools/src/fetch.ts                   | 21 ++++++++++++++++---
 5 files changed, 33 insertions(+), 24 deletions(-)

diff --git a/packages/cli/src/commands/init/__tests__/templateName.test.js b/packages/cli/src/commands/init/__tests__/templateName.test.js
index 748849e4f..d374637dc 100644
--- a/packages/cli/src/commands/init/__tests__/templateName.test.js
+++ b/packages/cli/src/commands/init/__tests__/templateName.test.js
@@ -1,8 +1,6 @@
 // @flow
 import {processTemplateName} from '../templateName';
 
-jest.mock('@react-native-community/cli-tools', () => ({fetch: jest.fn()}));
-
 const RN_NPM_PACKAGE = 'react-native';
 const ABS_RN_PATH = '/path/to/react-native';
 
diff --git a/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js b/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
index 4a4857722..f55215f7a 100644
--- a/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
+++ b/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
@@ -45,9 +45,7 @@ jest.mock('../../../tools/packageManager', () => ({
 }));
 jest.mock('@react-native-community/cli-tools', () => ({
   ...jest.requireActual('@react-native-community/cli-tools'),
-  fetch: jest.fn(() =>
-    Promise.resolve({json: () => Promise.resolve('patch'), status: 200}),
-  ),
+  fetch: jest.fn(() => Promise.resolve({data: 'patch', status: 200})),
   logger: {
     info: jest.fn((...args) => mockPushLog('info', args)),
     error: jest.fn((...args) => mockPushLog('error', args)),
@@ -59,9 +57,7 @@ jest.mock('@react-native-community/cli-tools', () => ({
 }));
 
 const mockFetch = (value, status) => {
-  (fetch: any).mockImplementation(() =>
-    Promise.resolve({json: () => Promise.resolve(value), status}),
-  );
+  (fetch: any).mockImplementation(() => Promise.resolve({data: value, status}));
 };
 
 const mockExecaDefault = (command, args) => {
@@ -184,9 +180,7 @@ test('fetches empty patch and installs deps', async () => {
 }, 60000);
 
 test('fetches regular patch, adds remote, applies patch, installs deps, removes remote,', async () => {
-  (fetch: any).mockImplementation(() =>
-    Promise.resolve({json: () => Promise.resolve(samplePatch), status: 200}),
-  );
+  mockFetch(samplePatch, 200);
   await upgrade.func(
     [newVersion],
     merge(ctx, {
diff --git a/packages/cli/src/commands/upgrade/upgrade.js b/packages/cli/src/commands/upgrade/upgrade.js
index 4e0818d8c..3beee1522 100644
--- a/packages/cli/src/commands/upgrade/upgrade.js
+++ b/packages/cli/src/commands/upgrade/upgrade.js
@@ -45,14 +45,14 @@ const getPatch = async (currentVersion, newVersion, config) => {
   logger.info(`Fetching diff between v${currentVersion} and v${newVersion}...`);
 
   try {
-    const response = await fetch(
+    const {status, data} = await fetch(
       `${rawDiffUrl}/${currentVersion}..${newVersion}.diff`,
     );
 
-    if (response.status < 200 || response.status > 299) {
-      throw new Error(`Failed to load page, status code: ${response.status}`);
+    if (status < 200 || status > 299) {
+      throw new Error(`Failed to load page, status code: ${status}`);
     }
-    patch = await response.json();
+    patch = data;
   } catch (error) {
     logger.error(
       `Failed to fetch diff for react-native@${newVersion}. Maybe it's not released yet?`,
diff --git a/packages/cli/src/tools/releaseChecker/getLatestRelease.js b/packages/cli/src/tools/releaseChecker/getLatestRelease.js
index d4cf005b7..e13bae679 100644
--- a/packages/cli/src/tools/releaseChecker/getLatestRelease.js
+++ b/packages/cli/src/tools/releaseChecker/getLatestRelease.js
@@ -81,17 +81,19 @@ async function getLatestRnDiffPurgeVersion(name: string, eTag: ?string) {
     options.headers['If-None-Match'] = eTag;
   }
 
-  const response = await fetch(options);
+  const {data, status, headers} = await fetch(options);
 
   // Remote is newer.
-  if (response.status === 200) {
-    const body: Array<any> = await response.json();
+  if (status === 200) {
+    const body: Array<any> = data;
     const latestVersion = body[0].name.substring(8);
 
     // Update cache only if newer release is stable.
     if (!semver.prerelease(latestVersion)) {
-      logger.debug(`Saving ${response.eTag} to cache`);
-      cacheManager.set(name, 'eTag', response.eTag);
+      const eTagHeader = headers.get('eTag');
+
+      logger.debug(`Saving ${eTagHeader} to cache`);
+      cacheManager.set(name, 'eTag', eTagHeader);
       cacheManager.set(name, 'latestVersion', latestVersion);
     }
 
@@ -99,7 +101,7 @@ async function getLatestRnDiffPurgeVersion(name: string, eTag: ?string) {
   }
 
   // Cache is still valid.
-  if (response.statusCode === 304) {
+  if (status === 304) {
     const latestVersion = cacheManager.get(name, 'latestVersion');
     if (latestVersion) {
       return latestVersion;
diff --git a/packages/tools/src/fetch.ts b/packages/tools/src/fetch.ts
index 1f9e7bc56..9b793d304 100644
--- a/packages/tools/src/fetch.ts
+++ b/packages/tools/src/fetch.ts
@@ -2,11 +2,26 @@ import nodeFetch, {
   RequestInit as FetchOptions,
   Response,
   Request,
+  Headers,
 } from 'node-fetch';
 
-export default function fetch(
+async function unwrapFetchResult(response: Response) {
+  try {
+    return response.json();
+  } catch (e) {
+    return response.text();
+  }
+}
+
+export default async function fetch(
   url: string | Request,
   options?: FetchOptions,
-): Promise<Response> {
-  return nodeFetch(url, options);
+): Promise<{status: number, data: any, headers: Headers}> {
+  const result = await nodeFetch(url, options);
+
+  return {
+    status: result.status,
+    headers: result.headers,
+    data: await unwrapFetchResult(result),
+  };
 }

From 911c986b34f113c7e770cfdfe1e2dde30c2f05a7 Mon Sep 17 00:00:00 2001
From: Kacper Wiszczuk <kacperwiszczuk@gmail.com>
Date: Tue, 16 Jul 2019 17:44:32 +0200
Subject: [PATCH 04/11] Fix isPackagerRunning

---
 packages/tools/src/isPackagerRunning.ts | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/packages/tools/src/isPackagerRunning.ts b/packages/tools/src/isPackagerRunning.ts
index b2b888005..ad97fb9ca 100644
--- a/packages/tools/src/isPackagerRunning.ts
+++ b/packages/tools/src/isPackagerRunning.ts
@@ -19,10 +19,9 @@ async function isPackagerRunning(
   packagerPort: string = process.env.RCT_METRO_PORT || '8081',
 ): Promise<'running' | 'not_running' | 'unrecognized'> {
   try {
-    const result = await fetch(`http://localhost:${packagerPort}/status`);
-    const body = await result.text();
+    const {data} = await fetch(`http://localhost:${packagerPort}/status`);
 
-    return body === 'packager-status:running' ? 'running' : 'unrecognized';
+    return data === 'packager-status:running' ? 'running' : 'unrecognized';
   } catch (_error) {
     return 'not_running';
   }

From 2bf2da520ab706bace120959edc51e246448ec89 Mon Sep 17 00:00:00 2001
From: Kacper Wiszczuk <kacperwiszczuk@gmail.com>
Date: Tue, 16 Jul 2019 17:54:43 +0200
Subject: [PATCH 05/11] Improve mocking

---
 jest/setupUnitTests.js                                      | 1 +
 packages/cli/src/commands/upgrade/__tests__/upgrade.test.js | 6 +++---
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/jest/setupUnitTests.js b/jest/setupUnitTests.js
index a6ea7c372..a48825526 100644
--- a/jest/setupUnitTests.js
+++ b/jest/setupUnitTests.js
@@ -5,6 +5,7 @@
 jest.mock('@react-native-community/cli-tools', () => {
   return {
     ...jest.requireActual('@react-native-community/cli-tools'),
+    fetch: jest.fn(),
     logger: {
       success: jest.fn(),
       info: jest.fn(),
diff --git a/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js b/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
index f55215f7a..064a7669a 100644
--- a/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
+++ b/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
@@ -45,7 +45,7 @@ jest.mock('../../../tools/packageManager', () => ({
 }));
 jest.mock('@react-native-community/cli-tools', () => ({
   ...jest.requireActual('@react-native-community/cli-tools'),
-  fetch: jest.fn(() => Promise.resolve({data: 'patch', status: 200})),
+  fetch: jest.fn(),
   logger: {
     info: jest.fn((...args) => mockPushLog('info', args)),
     error: jest.fn((...args) => mockPushLog('error', args)),
@@ -56,7 +56,7 @@ jest.mock('@react-native-community/cli-tools', () => ({
   },
 }));
 
-const mockFetch = (value, status) => {
+const mockFetch = (value = '', status = 200) => {
   (fetch: any).mockImplementation(() => Promise.resolve({data: value, status}));
 };
 
@@ -164,7 +164,7 @@ test('warns when dependency upgrade version is in semver range', async () => {
 }, 60000);
 
 test('fetches empty patch and installs deps', async () => {
-  mockFetch('', 200);
+  mockFetch();
   await upgrade.func([newVersion], ctx, opts);
   expect(flushOutput()).toMatchInlineSnapshot(`
     "info Fetching diff between v0.57.8 and v0.58.4...

From 834c15c72d35de1e1e52bab7db36faf8435dc2f7 Mon Sep 17 00:00:00 2001
From: Kacper Wiszczuk <kacperwiszczuk@gmail.com>
Date: Tue, 16 Jul 2019 18:03:56 +0200
Subject: [PATCH 06/11] Fix release checker

---
 packages/cli/src/tools/releaseChecker/getLatestRelease.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/packages/cli/src/tools/releaseChecker/getLatestRelease.js b/packages/cli/src/tools/releaseChecker/getLatestRelease.js
index e13bae679..d3980e8a2 100644
--- a/packages/cli/src/tools/releaseChecker/getLatestRelease.js
+++ b/packages/cli/src/tools/releaseChecker/getLatestRelease.js
@@ -71,8 +71,6 @@ function buildChangelogUrl(version: string) {
  */
 async function getLatestRnDiffPurgeVersion(name: string, eTag: ?string) {
   const options = {
-    hostname: 'api.github.com',
-    path: '/repos/react-native-community/rn-diff-purge/tags',
     // https://developer.github.com/v3/#user-agent-required
     headers: ({'User-Agent': 'React-Native-CLI'}: Headers),
   };
@@ -81,7 +79,10 @@ async function getLatestRnDiffPurgeVersion(name: string, eTag: ?string) {
     options.headers['If-None-Match'] = eTag;
   }
 
-  const {data, status, headers} = await fetch(options);
+  const {data, status, headers} = await fetch(
+    'https://api.github.com/repos/react-native-community/rn-diff-purge/tags',
+    options,
+  );
 
   // Remote is newer.
   if (status === 200) {

From 18900546368583bf526ebedb1264d27a15517018 Mon Sep 17 00:00:00 2001
From: Kacper Wiszczuk <kacperwiszczuk@gmail.com>
Date: Tue, 16 Jul 2019 18:32:05 +0200
Subject: [PATCH 07/11] Fix upgrade

---
 packages/cli/src/commands/upgrade/upgrade.js |  3 ++-
 packages/cli/src/tools/fetch.js              | 17 -----------------
 packages/tools/src/fetch.ts                  |  9 ++++++---
 3 files changed, 8 insertions(+), 21 deletions(-)
 delete mode 100644 packages/cli/src/tools/fetch.js

diff --git a/packages/cli/src/commands/upgrade/upgrade.js b/packages/cli/src/commands/upgrade/upgrade.js
index 3beee1522..609c423ec 100644
--- a/packages/cli/src/commands/upgrade/upgrade.js
+++ b/packages/cli/src/commands/upgrade/upgrade.js
@@ -50,10 +50,11 @@ const getPatch = async (currentVersion, newVersion, config) => {
     );
 
     if (status < 200 || status > 299) {
-      throw new Error(`Failed to load page, status code: ${status}`);
+      throw new CLIError(`Failed to get diff, status code: ${status}`);
     }
     patch = data;
   } catch (error) {
+    logger.error(error);
     logger.error(
       `Failed to fetch diff for react-native@${newVersion}. Maybe it's not released yet?`,
     );
diff --git a/packages/cli/src/tools/fetch.js b/packages/cli/src/tools/fetch.js
deleted file mode 100644
index 5c9ad2fc2..000000000
--- a/packages/cli/src/tools/fetch.js
+++ /dev/null
@@ -1,17 +0,0 @@
-// @flow
-import https from 'https';
-
-export const fetch = (url: string) =>
-  new Promise<string>((resolve, reject) => {
-    const request = https.get(url, response => {
-      if (response.statusCode < 200 || response.statusCode > 299) {
-        reject(
-          new Error(`Failed to load page, status code: ${response.statusCode}`),
-        );
-      }
-      const body = [];
-      response.on('data', chunk => body.push(chunk));
-      response.on('end', () => resolve(body.join('')));
-    });
-    request.on('error', err => reject(err));
-  });
diff --git a/packages/tools/src/fetch.ts b/packages/tools/src/fetch.ts
index 9b793d304..d2afbbbbc 100644
--- a/packages/tools/src/fetch.ts
+++ b/packages/tools/src/fetch.ts
@@ -6,10 +6,12 @@ import nodeFetch, {
 } from 'node-fetch';
 
 async function unwrapFetchResult(response: Response) {
+  const data = await response.text();
+
   try {
-    return response.json();
+    return JSON.stringify(data);
   } catch (e) {
-    return response.text();
+    return data;
   }
 }
 
@@ -18,10 +20,11 @@ export default async function fetch(
   options?: FetchOptions,
 ): Promise<{status: number, data: any, headers: Headers}> {
   const result = await nodeFetch(url, options);
+  const data = await unwrapFetchResult(result);
 
   return {
     status: result.status,
     headers: result.headers,
-    data: await unwrapFetchResult(result),
+    data,
   };
 }

From da3e461b7f0d3b493bc98fed6df3feb65fd441b4 Mon Sep 17 00:00:00 2001
From: Kacper Wiszczuk <kacperwiszczuk@gmail.com>
Date: Tue, 16 Jul 2019 18:42:27 +0200
Subject: [PATCH 08/11] Handle status codes inside fetch

---
 packages/cli/src/commands/upgrade/upgrade.js | 5 +----
 packages/tools/src/fetch.ts                  | 5 +++++
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/packages/cli/src/commands/upgrade/upgrade.js b/packages/cli/src/commands/upgrade/upgrade.js
index 609c423ec..15afbf3a1 100644
--- a/packages/cli/src/commands/upgrade/upgrade.js
+++ b/packages/cli/src/commands/upgrade/upgrade.js
@@ -45,13 +45,10 @@ const getPatch = async (currentVersion, newVersion, config) => {
   logger.info(`Fetching diff between v${currentVersion} and v${newVersion}...`);
 
   try {
-    const {status, data} = await fetch(
+    const {data} = await fetch(
       `${rawDiffUrl}/${currentVersion}..${newVersion}.diff`,
     );
 
-    if (status < 200 || status > 299) {
-      throw new CLIError(`Failed to get diff, status code: ${status}`);
-    }
     patch = data;
   } catch (error) {
     logger.error(error);
diff --git a/packages/tools/src/fetch.ts b/packages/tools/src/fetch.ts
index d2afbbbbc..c8cc62c95 100644
--- a/packages/tools/src/fetch.ts
+++ b/packages/tools/src/fetch.ts
@@ -4,6 +4,7 @@ import nodeFetch, {
   Request,
   Headers,
 } from 'node-fetch';
+import {CLIError} from './errors';
 
 async function unwrapFetchResult(response: Response) {
   const data = await response.text();
@@ -22,6 +23,10 @@ export default async function fetch(
   const result = await nodeFetch(url, options);
   const data = await unwrapFetchResult(result);
 
+  if (result.status >= 400) {
+    throw new CLIError(`Fetch request failed with status ${result.status}`);
+  }
+
   return {
     status: result.status,
     headers: result.headers,

From 704920f6b99d1a19aab19fe67dec7a232b0c9f4d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Pierzcha=C5=82a?= <thymikee@gmail.com>
Date: Tue, 16 Jul 2019 20:34:48 +0200
Subject: [PATCH 09/11] use logger from cli-tools

---
 packages/cli/src/commands/upgrade/__tests__/upgrade.test.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js b/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
index 064a7669a..af689b03e 100644
--- a/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
+++ b/packages/cli/src/commands/upgrade/__tests__/upgrade.test.js
@@ -5,8 +5,7 @@ import fs from 'fs';
 import snapshotDiff from 'snapshot-diff';
 import stripAnsi from 'strip-ansi';
 import upgrade from '../upgrade';
-import {fetch} from '@react-native-community/cli-tools';
-import logger from '../../../tools/logger';
+import {fetch, logger} from '@react-native-community/cli-tools';
 import loadConfig from '../../../tools/config';
 import merge from '../../../tools/merge';
 

From 8296696405d861b02d1626f06422467bd4e9109f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Pierzcha=C5=82a?= <thymikee@gmail.com>
Date: Tue, 16 Jul 2019 20:45:51 +0200
Subject: [PATCH 10/11] add more details to fetch failure

---
 packages/cli/src/commands/upgrade/upgrade.js | 2 +-
 packages/tools/src/fetch.ts                  | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/packages/cli/src/commands/upgrade/upgrade.js b/packages/cli/src/commands/upgrade/upgrade.js
index 15afbf3a1..b20b788e9 100644
--- a/packages/cli/src/commands/upgrade/upgrade.js
+++ b/packages/cli/src/commands/upgrade/upgrade.js
@@ -51,7 +51,7 @@ const getPatch = async (currentVersion, newVersion, config) => {
 
     patch = data;
   } catch (error) {
-    logger.error(error);
+    logger.error(error.message);
     logger.error(
       `Failed to fetch diff for react-native@${newVersion}. Maybe it's not released yet?`,
     );
diff --git a/packages/tools/src/fetch.ts b/packages/tools/src/fetch.ts
index c8cc62c95..098ab0d6d 100644
--- a/packages/tools/src/fetch.ts
+++ b/packages/tools/src/fetch.ts
@@ -24,7 +24,9 @@ export default async function fetch(
   const data = await unwrapFetchResult(result);
 
   if (result.status >= 400) {
-    throw new CLIError(`Fetch request failed with status ${result.status}`);
+    throw new CLIError(
+      `Fetch request failed with status ${result.status}: ${data}.`,
+    );
   }
 
   return {

From 6a2331498ac98a02263ac58b96beff65f86acbe4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Pierzcha=C5=82a?= <thymikee@gmail.com>
Date: Tue, 16 Jul 2019 20:48:06 +0200
Subject: [PATCH 11/11] parse text repsonse

---
 packages/tools/src/fetch.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/tools/src/fetch.ts b/packages/tools/src/fetch.ts
index 098ab0d6d..73cc8cdd5 100644
--- a/packages/tools/src/fetch.ts
+++ b/packages/tools/src/fetch.ts
@@ -10,7 +10,7 @@ async function unwrapFetchResult(response: Response) {
   const data = await response.text();
 
   try {
-    return JSON.stringify(data);
+    return JSON.parse(data);
   } catch (e) {
     return data;
   }