Run git commands in dedicated renderer process

.eslintrc

@@ -20,6 +20,7 @@
     "MouseEvent": true,
     "IDBKeyRange": true,
     "beforeEach": true,
+    "after": true,
     "afterEach": true,
     "describe": true,
     "fdescribe": true,

lib/async-queue.js

@@ -39,9 +39,6 @@ export default class AsyncQueue {
   }
 
   push(fn, {parallel} = {parallel: true}) {
-    if (this.disposed) {
-      throw new Error('AsyncQueue is disposed');
-    }
     const task = new Task(fn, parallel);
     this.queue.push(task);
     this.processQueue();

lib/controllers/git-tab-controller.js

@@ -226,7 +226,7 @@ export default class GitTabController {
     const pathsToIgnore = [];
     const repository = this.getActiveRepository();
     for (const filePath of filePaths) {
-      if (await repository.pathHasMergeMarkers(filePath)) { // eslint-disable-line babel/no-await-in-loop
+      if (await repository.pathHasMergeMarkers(filePath)) { // eslint-disable-line no-await-in-loop
         const choice = atom.confirm({
           message: 'File contains merge markers: ',
           detailedMessage: `Do you still want to stage this file?\n${filePath}`,

lib/git-shell-out-strategy.js

@@ -2,14 +2,14 @@ import path from 'path';
 import os from 'os';
 
 import {CompositeDisposable} from 'event-kit';
-
 import {GitProcess} from 'dugite';
 import {parse as parseDiff} from 'what-the-diff';
 
 import GitPromptServer from './git-prompt-server';
 import AsyncQueue from './async-queue';
-import {getPackageRoot, getDugitePath, readFile, fileExists, writeFile, isFileExecutable} from './helpers';
+import {getPackageRoot, getDugitePath, readFile, fileExists, fsStat, writeFile, isFileExecutable} from './helpers';
 import GitTimingsView from './views/git-timings-view';
+import WorkerManager from './worker-manager';
 
 const LINE_ENDING_REGEX = /\r?\n/;
 
@@ -57,6 +57,7 @@ export default class GitShellOutStrategy {
     }
 
     this.prompt = options.prompt || (query => Promise.reject());
+    this.workerManager = options.workerManager;
   }
 
   /*
@@ -131,6 +132,7 @@ export default class GitShellOutStrategy {
       const options = {
         env,
         processCallback: child => {
+          // TODO: move callback to renderer process. send child.pid back to add cancel listener
           child.on('error', err => {
             console.warn('Error executing: ' + formattedArgs + ':');
             console.warn(err.stack);
@@ -156,51 +158,68 @@ export default class GitShellOutStrategy {
       if (process.env.PRINT_GIT_TIMES) {
         console.time(`git:${formattedArgs}`);
       }
-      return new Promise(resolve => {
-        timingMarker.mark('nexttick');
-        setImmediate(() => {
-          timingMarker.mark('execute');
-          resolve(GitProcess.exec(args, this.workingDir, options)
-            .then(({stdout, stderr, exitCode}) => {
-              timingMarker.finalize();
-              if (process.env.PRINT_GIT_TIMES) {
-                console.timeEnd(`git:${formattedArgs}`);
-              }
-              if (gitPromptServer) {
-                gitPromptServer.terminate();
-              }
-              subscriptions.dispose();
-
-              if (diagnosticsEnabled) {
-                const headerStyle = 'font-weight: bold; color: blue;';
-
-                console.groupCollapsed(`git:${formattedArgs}`);
-                console.log('%cexit status%c %d', headerStyle, 'font-weight: normal; color: black;', exitCode);
-                console.log('%cstdout', headerStyle);
-                console.log(stdout);
-                console.log('%cstderr', headerStyle);
-                console.log(stderr);
-                console.groupEnd();
-              }
-
-              if (exitCode) {
-                const err = new GitError(
-                  `${formattedArgs} exited with code ${exitCode}\nstdout: ${stdout}\nstderr: ${stderr}`,
-                );
-                err.code = exitCode;
-                err.stdErr = stderr;
-                err.stdOut = stdout;
-                err.command = formattedArgs;
-                return Promise.reject(err);
-              }
-              return stdout;
-            }));
-        });
+      return new Promise(async (resolve, reject) => {
+        const {stdout, stderr, exitCode, timing} = await this.executeGitCommand(args, options, timingMarker);
+        if (timing) {
+          const {execTime, spawnTime, ipcTime} = timing;
+          const now = performance.now();
+          timingMarker.mark('nexttick', now - execTime - spawnTime - ipcTime);
+          timingMarker.mark('execute', now - execTime - ipcTime);
+          timingMarker.mark('ipc', now - ipcTime);
+        }
+        timingMarker.finalize();
+        if (process.env.PRINT_GIT_TIMES) {
+          console.timeEnd(`git:${formattedArgs}`);
+        }
+        if (gitPromptServer) {
+          gitPromptServer.terminate();
+        }
+        subscriptions.dispose();
+
+        if (diagnosticsEnabled) {
+          const headerStyle = 'font-weight: bold; color: blue;';
+
+          console.groupCollapsed(`git:${formattedArgs}`);
+          console.log('%cexit status%c %d', headerStyle, 'font-weight: normal; color: black;', exitCode);
+          console.log('%cstdout', headerStyle);
+          console.log(stdout);
+          console.log('%cstderr', headerStyle);
+          console.log(stderr);
+          console.groupEnd();
+        }
+
+        if (exitCode) {
+          const err = new GitError(
+            `${formattedArgs} exited with code ${exitCode}\nstdout: ${stdout}\nstderr: ${stderr}`,
+          );
+          err.code = exitCode;
+          err.stdErr = stderr;
+          err.stdOut = stdout;
+          err.command = formattedArgs;
+          reject(err);
+        }
+        resolve(stdout);
       });
     }, {parallel: !writeOperation});
     /* eslint-enable no-console */
   }
 
+  executeGitCommand(args, options, marker = null) {
+    if (process.env.ATOM_GITHUB_INLINE_GIT_EXEC || !WorkerManager.getInstance().isReady()) {
+      marker && marker.mark('nexttick');
+      const promise = GitProcess.exec(args, this.workingDir, options);
+      marker && marker.mark('execute');
+      return promise;
+    } else {
+      const workerManager = this.workerManager || WorkerManager.getInstance();
+      return workerManager.request({
+        args,
+        workingDir: this.workingDir,
+        options,
+      });
+    }
+  }
+
   /**
    * Execute a git command that may create a commit. If the command fails because the GPG binary was invoked and unable
    * to acquire a passphrase (because the pinentry program attempted to use a tty), retry with a `GitPromptServer`.
@@ -220,6 +239,7 @@ export default class GitShellOutStrategy {
 
   async isGitRepository() {
     try {
+      await fsStat(this.workingDir); // fails if folder doesn't exist
       await this.exec(['rev-parse', '--resolve-git-dir', path.join(this.workingDir, '.git')]);
       return true;
     } catch (e) {

lib/github-package.js

@@ -19,6 +19,7 @@ import Switchboard from './switchboard';
 import yardstick from './yardstick';
 import GitTimingsView from './views/git-timings-view';
 import AsyncQueue from './async-queue';
+import WorkerManager from './worker-manager';
 
 const defaultState = {
   firstRun: true,
@@ -216,6 +217,7 @@ export default class GithubPackage {
     this.subscriptions.dispose();
     this.contextPool.clear();
     await yardstick.flush();
+    WorkerManager.reset();
   }
 
   @autobind

lib/renderer.html

@@ -0,0 +1,19 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8">
+    <title></title>
+    <script type="text/javascript">
+      const qs = require('querystring')
+      const jsPath = qs.parse(window.location.search.substr(1)).js
+      require(jsPath)
+    </script>
+  </head>
+  <body>
+    <h1>GitHub Package Git Execution Window</h1>
+    <p>
+      Hi there! I'm a window used by the GitHub package to execute Git commands in the background. My PID is <script>document.write(process.pid)</script>.
+    </p>
+    <p>Last command: <span id='command'></span></p>
+  </body>
+</html>

lib/views/git-timings-view.js

@@ -43,8 +43,8 @@ class Marker {
     return this.end;
   }
 
-  mark(sectionName) {
-    this.markers.push({name: sectionName, start: performance.now()});
+  mark(sectionName, start) {
+    this.markers.push({name: sectionName, start: start || performance.now()});
   }
 
   finalize() {
@@ -98,6 +98,7 @@ const COLORS = {
   prepare: 'cyan',
   nexttick: 'yellow',
   execute: 'green',
+  ipc: 'pink',
 };
 class MarkerSpan extends React.Component {
   static propTypes = {