Rely on cross-fetch

And rely on cross-fetch directly, as that version provides the desired
interface.

Due to "self is not defined" JakeChampion/fetch#657

Libraries/Core/Devtools/symbolicateStackTrace.js

@@ -26,19 +26,19 @@ function isSourcedFromDisk(sourcePath: string): boolean {
 async function symbolicateStackTrace(
   stack: Array<StackFrame>,
 ): Promise<Array<StackFrame>> {
-  // RN currently lazy loads whatwg-fetch using a custom fetch module, which,
-  // when called for the first time, requires and re-exports 'whatwg-fetch'.
-  // However, when a dependency of the project tries to require whatwg-fetch
-  // either directly or indirectly, whatwg-fetch is required before
-  // RN can lazy load whatwg-fetch. As whatwg-fetch checks
+  // RN currently lazy loads cross-fetch using a custom fetch module, which,
+  // when called for the first time, requires and re-exports 'cross-fetch'.
+  // However, when a dependency of the project tries to require cross-fetch
+  // either directly or indirectly, cross-fetch is required before
+  // RN can lazy load cross-fetch. As cross-fetch checks
   // for a fetch polyfill before loading, it will in turn try to load
-  // RN's fetch module, which immediately tries to import whatwg-fetch AGAIN.
+  // RN's fetch module, which immediately tries to import cross-fetch AGAIN.
   // This causes a circular require which results in RN's fetch module
   // exporting fetch as 'undefined'.
   // The fix below postpones trying to load fetch until the first call to symbolicateStackTrace.
-  // At that time, we will have either global.fetch (whatwg-fetch) or RN's fetch.
+  // At that time, we will have either global.fetch (cross-fetch) or RN's fetch.
   if (!fetch) {
-    fetch = global.fetch || require('fetch').fetch;
+    fetch = global.fetch || require('cross-fetch').fetch;
   }
 
   const devServer = getDevServer();

Libraries/Core/setUpXHR.js

@@ -20,10 +20,10 @@ const {polyfillGlobal} = require('PolyfillFunctions');
 polyfillGlobal('XMLHttpRequest', () => require('XMLHttpRequest'));
 polyfillGlobal('FormData', () => require('FormData'));
 
-polyfillGlobal('fetch', () => require('fetch').fetch); // flowlint-line untyped-import:off
-polyfillGlobal('Headers', () => require('fetch').Headers); // flowlint-line untyped-import:off
-polyfillGlobal('Request', () => require('fetch').Request); // flowlint-line untyped-import:off
-polyfillGlobal('Response', () => require('fetch').Response); // flowlint-line untyped-import:off
+polyfillGlobal('fetch', () => require('cross-fetch').fetch); // flowlint-line untyped-import:off
+polyfillGlobal('Headers', () => require('cross-fetch').Headers); // flowlint-line untyped-import:off
+polyfillGlobal('Request', () => require('cross-fetch').Request); // flowlint-line untyped-import:off
+polyfillGlobal('Response', () => require('cross-fetch').Response); // flowlint-line untyped-import:off
 polyfillGlobal('WebSocket', () => require('WebSocket'));
 polyfillGlobal('Blob', () => require('Blob'));
 polyfillGlobal('File', () => require('File'));

package.json

@@ -168,6 +168,7 @@
     "compression": "^1.7.1",
     "connect": "^3.6.5",
     "create-react-class": "^15.6.3",
+    "cross-fetch": "^3.0.1",
     "debug": "^2.2.0",
     "denodeify": "^1.2.1",
     "errorhandler": "^1.5.0",
@@ -187,7 +188,6 @@
     "minimist": "^1.2.0",
     "mkdirp": "^0.5.1",
     "morgan": "^1.9.0",
-    "node-fetch": "^2.2.0",
     "node-notifier": "^5.2.1",
     "npmlog": "^2.0.4",
     "nullthrows": "^1.1.0",
@@ -205,7 +205,6 @@
     "serve-static": "^1.13.1",
     "shell-quote": "1.6.1",
     "stacktrace-parser": "^0.1.3",
-    "whatwg-fetch": "^1.0.0",
     "ws": "^1.1.5",
     "xmldoc": "^0.4.0",
     "yargs": "^9.0.0"
@@ -257,4 +256,4 @@
       }
     }
   }
-}
+}

yarn.lock

@@ -2540,6 +2540,14 @@ create-react-class@^15.6.3:
     loose-envify "^1.3.1"
     object-assign "^4.1.1"
 
+cross-fetch@^3.0.1:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/cross-fetch/-/cross-fetch-3.0.1.tgz#3f207bbd829a76e9aa2a953348bd1f2a3cf388a7"
+  integrity sha512-qWtpgBAF8ioqBOddRD+pHhrdzm/UWOArkrlIU7c08DlNbOxo5GfUbSY2vr90ZypWf0raW+HNN1F38pi5CEOjiQ==
+  dependencies:
+    node-fetch "2.3.0"
+    whatwg-fetch "3.0.0"
+
 cross-spawn@^4.0.2:
   version "4.0.2"
   resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-4.0.2.tgz#7b9247621c23adfdd3856004a823cbe397424d41"
@@ -5823,6 +5831,11 @@ node-dir@^0.1.17:
   dependencies:
     minimatch "^3.0.2"
 
+node-fetch@2.3.0:
+  version "2.3.0"
+  resolved "https://registry.yarnpkg.com/node-fetch/-/node-fetch-2.3.0.tgz#1a1d940bbfb916a1d3e0219f037e89e71f8c5fa5"
+  integrity sha512-MOd8pV3fxENbryESLgVIeaGKrdl+uaYhCSSVkjeOb/31/njTpcis5aWfdqgNlHIrKOLRbMnfPINPOML2CIFeXA==
+
 node-fetch@^1.0.1:
   version "1.7.3"
   resolved "https://registry.yarnpkg.com/node-fetch/-/node-fetch-1.7.3.tgz#980f6f72d85211a5347c6b2bc18c5b84c3eb47ef"
@@ -7857,7 +7870,7 @@ whatwg-encoding@^1.0.1, whatwg-encoding@^1.0.3:
   dependencies:
     iconv-lite "0.4.24"
 
-whatwg-fetch@>=0.10.0:
+whatwg-fetch@3.0.0, whatwg-fetch@>=0.10.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/whatwg-fetch/-/whatwg-fetch-3.0.0.tgz#fc804e458cc460009b1a2b966bc8817d2578aefb"
   integrity sha512-9GSJUgz1D4MfyKU7KRqwOjXCXTqWdFNvEr7eUBYchQiVc744mqK/MzXPNR2WsPkmkOa4ywfg8C2n8h+13Bey1Q==