improve based on CR

packages/jest-cli/src/reporters/coverage_worker.js

@@ -37,6 +37,12 @@ function formatCoverageError(error, filename: Path): SerializableError {
   };
 }
 
+// Make sure uncaught errors are logged before we exit.
+process.on('uncaughtException', err => {
+  console.error(err.stack);
+  process.exit(1);
+});
+
 module.exports = (
   {config, globalConfig, path}: CoverageWorkerData,
   callback: WorkerCallback,

packages/jest-jasmine2/src/jasmine/Env.js

@@ -197,6 +197,17 @@ module.exports = function(j$) {
         }
       };
 
+      // Need to ensure we are the only ones handling these exceptions.
+      const oldListenersException = process
+        .listeners('uncaughtException')
+        .slice();
+      const oldListenersRejection = process
+        .listeners('unhandledRejection')
+        .slice();
+
+      process.removeAllListeners('uncaughtException');
+      process.removeAllListeners('unhandledRejection');
+
       process.on('uncaughtException', uncaught);
       process.on('unhandledRejection', uncaught);
 
@@ -229,6 +240,15 @@ module.exports = function(j$) {
 
       process.removeListener('uncaughtException', uncaught);
       process.removeListener('unhandledRejection', uncaught);
+
+      // restore previous exception handlers
+      oldListenersException.forEach(listener => {
+        process.on('uncaughtException', listener);
+      });
+
+      oldListenersRejection.forEach(listener => {
+        process.on('unhandledRejection', listener);
+      });
     };
 
     this.addReporter = function(reporterToAdd) {

packages/jest-jasmine2/src/queue_runner.js

@@ -71,15 +71,15 @@ function queueRunner(options: Options) {
     );
   };
 
-  const res = options.queueableFns.reduce(
+  const result = options.queueableFns.reduce(
     (promise, fn) => promise.then(() => mapper(fn)),
     Promise.resolve(),
   );
 
   return {
     cancel: token.cancel.bind(token),
-    catch: res.catch.bind(res),
-    then: res.then.bind(res),
+    catch: result.catch.bind(result),
+    then: result.then.bind(result),
   };
 }
 

packages/jest-runner/src/test_worker.js

@@ -12,6 +12,12 @@ import type {GlobalConfig, Path, ProjectConfig} from 'types/Config';
 import type {SerializableError, TestResult} from 'types/TestResult';
 import type {RawModuleMap} from 'types/HasteMap';
 
+// Make sure uncaught errors are logged before we exit.
+process.on('uncaughtException', err => {
+  console.error(err.stack);
+  process.exit(1);
+});
+
 import HasteMap from 'jest-haste-map';
 import {separateMessageFromStack} from 'jest-message-util';
 import Runtime from 'jest-runtime';