Prevent Jest from configuring Error source-maps

Author: Brian Vaughn

packages/react-devtools-extensions/src/__tests__/__source__/__compiled__/external/ComponentWithExternalCustomHooks.js

@@ -27,6 +27,11 @@ describe('parseHookNames', () => {
       .inspectHooks;
     parseHookNames = require('../parseHookNames').default;
 
+    // Jest (jest-runner?) configures Errors to automatically account for source maps.
+    // This changes behavior between our tests and the browser.
+    // To "fix" this, clear the prepareStackTrace() method on the Error object.
+    delete Error.prepareStackTrace;
+
     fetchMock.mockIf(/.+$/, request => {
       const {resolve} = require('path');
       const url = request.url;

packages/react-devtools-extensions/src/__tests__/__source__/__compiled__/external/Example.js

@@ -44,12 +44,9 @@ function compile(fileName) {
   // Generate compiled output with external source maps
   writeFileSync(
     resolve(externalDir, fileName),
-    // This comment format (//##) isn't valid;
-    // but it prevents Node from auto-applying source maps to stack traces
-    // which lets unit tests more accurately simulate browser behavior.
     transformed.code +
-      `\n//## sourceMappingURL=${fileName}.map` +
-      `\n//## sourceURL=${fileName}`,
+      `\n//# sourceMappingURL=${fileName}.map` +
+      `\n//# sourceURL=${fileName}`,
     'utf8',
   );
   writeFileSync(
@@ -61,13 +58,10 @@ function compile(fileName) {
   // Generate compiled output with external inline base64 source maps
   writeFileSync(
     resolve(inlineDir, fileName),
-    // This comment format (//##) isn't valid;
-    // but it prevents Node from auto-applying source maps to stack traces
-    // which lets unit tests more accurately simulate browser behavior.
     transformed.code +
-      '\n//## sourceMappingURL=data:application/json;charset=utf-8;base64,' +
+      '\n//# sourceMappingURL=data:application/json;charset=utf-8;base64,' +
       btoa(JSON.stringify(sourceMap)) +
-      `\n//## sourceURL=${fileName}`,
+      `\n//# sourceURL=${fileName}`,
     'utf8',
   );
 }