From 42b73d5a84f7335b722c7decad24d8069dfc3722 Mon Sep 17 00:00:00 2001
From: Matthew Gordon <matthew.gordon@arm.com>
Date: Wed, 26 Feb 2020 14:17:20 +0000
Subject: [PATCH] Set product name for Electron example app.

- Added main and productName entries to the example package.json.
- When starting the app with `theia start` or from the vscode launch
configurations, pass the example directory rather than the
electron-main script if possible.

This means that an IDE developer can work on multiple Theia
applications on the same machine without them sharing local storage.

Signed-off-by: Matthew Gordon <matthew.gordon@arm.com>
---
 .vscode/launch.json                              |  3 ++-
 .../src/application-package-manager.ts           | 16 +++++++++++++++-
 examples/electron/package.json                   |  2 ++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/.vscode/launch.json b/.vscode/launch.json
index 825f002eca906..5a5a5af3b346e 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -24,9 +24,10 @@
       "windows": {
         "runtimeExecutable": "${workspaceRoot}/node_modules/.bin/electron.cmd"
       },
-      "program": "${workspaceRoot}/examples/electron/src-gen/frontend/electron-main.js",
+      "cwd": "${workspaceRoot}/examples/electron",
       "protocol": "inspector",
       "args": [
+        ".",
         "--log-level=debug",
         "--hostname=localhost",
         "--no-cluster",
diff --git a/dev-packages/application-manager/src/application-package-manager.ts b/dev-packages/application-manager/src/application-package-manager.ts
index 318ea866e313f..976fd127f6cc2 100644
--- a/dev-packages/application-manager/src/application-package-manager.ts
+++ b/dev-packages/application-manager/src/application-package-manager.ts
@@ -78,7 +78,21 @@ export class ApplicationPackageManager {
     }
 
     startElectron(args: string[]): cp.ChildProcess {
-        const { mainArgs, options } = this.adjustArgs([this.pck.frontend('electron-main.js'), ...args]);
+        // If possible, pass the project root directory to electron rather than the script file so that Electron
+        // can determine the app name. This requires that the package.json has a main field.
+        let appPath = this.pck.projectPath;
+
+        if (!this.pck.pck.main) {
+            appPath = this.pck.frontend('electron-main.js');
+
+            console.warn(
+                `WARNING: ${this.pck.packagePath} does not have a "main" entry.\n` +
+                'Please add the following line:\n' +
+                '    "main": "src-gen/frontend/electron-main.js"'
+            );
+        }
+
+        const { mainArgs, options } = this.adjustArgs([ appPath, ...args ]);
         const electronCli = require.resolve('electron/cli.js', { paths: [this.pck.projectPath] });
         return this.__process.fork(electronCli, mainArgs, options);
     }
diff --git a/examples/electron/package.json b/examples/electron/package.json
index c322cac083846..3ca6031654259 100644
--- a/examples/electron/package.json
+++ b/examples/electron/package.json
@@ -1,7 +1,9 @@
 {
   "private": true,
   "name": "@theia/example-electron",
+  "productName": "Theia Electron Example",
   "version": "0.16.0",
+  "main": "src-gen/frontend/electron-main.js",
   "license": "EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0",
   "theia": {
     "target": "electron",