Reimplement _run() to use run().

yeoman · Nov 17, 2020 · f61d58c · f61d58c
1 parent 6b074ab
commit f61d58c
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Showing 2 changed files with 24 additions and 83 deletions.
diff --git a/lib/run-context.js b/lib/run-context.js
@@ -10,21 +10,6 @@ const {EventEmitter} = require('events');
 const helpers = require('.');
 const RunResult = require('./run-result');
 
-/**
- * Wrap callback so it can't get called twice
- */
-const callbackWrapper = (done) => {
-  let callbackHandled = false;
-  const callback = (err) => {
-    if (!callbackHandled) {
-      callbackHandled = true;
-      done(err);
-    }
-  };
-
-  return callback;
-};
-
 /**
  * This class provide a run context object to façade the complexity involved in setting
  * up a generator for testing
@@ -170,26 +155,27 @@ RunContext.prototype._run = function () {
   this.buildAsync = true;
   if (this.build() === false) return false;
 
-  const endCallback = callbackWrapper((envOrGenerator) => {
-    helpers.restorePrompt(envOrGenerator);
-    this.emit('end');
-    this.completed = true;
-  });
-
-  const callback = callbackWrapper((err) => {
-    helpers.restorePrompt(this.env);
-    this.errored = true;
-    this.emit('error', err);
-  });
-
-  // Yeoman-generator >=5.0.0 doesn't emits error on itself, it emits on the environment.
-  this.generator.on('error', callback);
-
-  this.env.on('error', callback);
-  this.env.runLoop.once('end', () => endCallback(this.generator));
   this.emit('ready', this.generator);
+  this.run()
+    .catch((error) => {
+      if (
+        this.listenerCount('end') === 0 &&
+        this.listenerCount('error') === 0
+      ) {
+        // When there is no listeners throw a unhandled rejection.
+        setImmediate(function () {
+          return Promise.reject(error);
+        });
+      } else {
+        this.errored = true;
+        this.emit('error', error);
+      }
+    })
+    .finally(() => {
+      this.emit('end');
+      this.completed = true;
+    });
 
-  this.generator.run().catch(callback);
   return true;
 };
 
@@ -198,7 +184,7 @@ RunContext.prototype._run = function () {
  * @return {Promise} Promise
  */
 RunContext.prototype.run = function () {
-  if (!this.settings.runEnvironment) {
+  if (!this.settings.runEnvironment && this.buildAsync === undefined) {
     throw new Error('Should be called with runEnvironment option');
   }
 

diff --git a/test/run-context.js b/test/run-context.js
@@ -215,51 +215,11 @@ describe('RunContext', function () {
   });
 
   describe('error handling', function () {
-    function removeListeners(host, handlerName) {
-      if (!host) {
-        return;
-      }
-
-      // Store the original handlers for the host
-      const originalHandlers = host.listeners(handlerName);
-      // Remove the current handlers for the host
-      host.removeAllListeners(handlerName);
-      return originalHandlers;
-    }
-
-    function setListeners(host, handlerName, handlers) {
-      if (!host) {
-        return;
-      }
-
-      handlers.forEach((handler) => host.on(handlerName, handler));
-    }
-
-    function processError(host, handlerName, cb) {
-      if (!host) {
-        return;
-      }
-
-      host.once(handlerName, cb);
-    }
-
-    beforeEach(function () {
-      this.originalHandlersProcess = removeListeners(
-        process,
-        'uncaughtException'
-      );
-      this.originalHandlersProcessDomain = removeListeners(
-        process.domain,
-        'error'
-      );
-    });
-
-    afterEach(function () {
-      setListeners(process, 'uncaughtException', this.originalHandlersProcess);
-      setListeners(process.domain, 'error', this.originalHandlersProcessDomain);
+    afterEach(() => {
+      process.removeAllListeners('unhandledRejection');
     });
 
-    it('throw an error when no listener is present', function (done) {
+    it('throw an unhandledRejection when no listener is present', function (done) {
       const error = new Error('dummy exception');
       const execSpy = sinon.stub().throws(error);
       const errorHandler = function (err) {
@@ -268,12 +228,7 @@ describe('RunContext', function () {
         done();
       };
 
-      // Tests can be run via 2 commands : 'gulp test' or 'mocha'
-      // in 'mocha' case the error has to be caught using process.on('uncaughtException')
-      // in 'gulp' case the error has to be caught using process.domain.on('error')
-      // as we don't know in which case we are, we set the error handler for both
-      processError(process, 'uncaughtException', errorHandler);
-      processError(process.domain, 'error', errorHandler);
+      process.once('unhandledRejection', errorHandler);
 
       const Dummy = helpers.createDummyGenerator();
       Dummy.prototype.exec = execSpy;