Support acquiring Blockly through Git instead of npm

plugins/dev-scripts/bin/blockly-scripts.js

@@ -14,7 +14,8 @@ const args = process.argv.slice(2);
 const {spawnSync} = require('child_process');
 
 const script = args[0];
-if (['build', 'start', 'clean', 'lint', 'test'].includes(script)) {
+if (['build', 'start', 'clean', 'lint', 'test', 'postinstall']
+    .includes(script)) {
   const result = spawnSync('node',
       [].concat(require.resolve('../scripts/' + script))
           .concat(args.slice(1)), {stdio: 'inherit'}

plugins/dev-scripts/config/webpack.config.js

@@ -18,6 +18,8 @@ const ForkTsCheckerWebpackPlugin = require('fork-ts-checker-webpack-plugin');
 const appDirectory = fs.realpathSync(process.cwd());
 const resolveApp = (relativePath) => path.resolve(appDirectory, relativePath);
 
+const packageJson = require(resolveApp('package.json'));
+
 module.exports = (env) => {
   const mode = env.mode;
   const isDevelopment = mode === 'development';
@@ -55,6 +57,16 @@ module.exports = (env) => {
     target = 'node';
   }
 
+  // Add 'dist' to the end of the blockly module alias if we have acquired
+  // blockly from git instead of npm.
+  let blocklyAliasSuffix = '';
+  const blocklyDependency =
+    (packageJson.dependencies && packageJson.dependencies['blockly']) ||
+    (packageJson.devDependencies && packageJson.devDependencies['blockly']);
+  if (blocklyDependency && blocklyDependency.indexOf('git://') === 0) {
+    blocklyAliasSuffix = '/dist';
+  }
+
   return {
     target,
     mode: isProduction ? 'production' : 'development',
@@ -69,7 +81,7 @@ module.exports = (env) => {
     },
     resolve: {
       alias: {
-        'blockly': resolveApp('node_modules/blockly'),
+        'blockly': resolveApp(`node_modules/blockly${blocklyAliasSuffix}`),
       },
       extensions: ['.ts', '.js']
           .filter((ext) => isTypescript || !ext.includes('ts')),

plugins/dev-scripts/scripts/postinstall.js

@@ -0,0 +1,49 @@
+/**
+ * @license
+ * Copyright 2020 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview A 'postinstall' script for Blockly extension packages.
+ * This script:
+ *   Completes post install tasks if necessary.
+ * @author samelh@google.com (Sam El-Husseini)
+ */
+
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+const execSync = require('child_process').execSync;
+
+const appDirectory = fs.realpathSync(process.cwd());
+const resolveApp = (relativePath) => path.resolve(appDirectory, relativePath);
+
+const packageJson = require(resolveApp('package.json'));
+const blocklyNodeModulesPath = resolveApp('node_modules/blockly');
+
+// Check if we have installed blockly from git instead of npm.
+const blocklyDependency =
+  (packageJson.dependencies && packageJson.dependencies['blockly']) ||
+  (packageJson.devDependencies && packageJson.devDependencies['blockly']);
+
+if (!blocklyDependency) {
+  return;
+}
+
+if (blocklyDependency.indexOf('git://') !== 0) {
+  return;
+}
+
+// Blockly was installed from a Git repo. Install and build.
+console.log(`Running postinstall steps for ${packageJson.name}`);
+
+// Run npm install.
+execSync(`npm install`, {cwd: blocklyNodeModulesPath, stdio: [0, 1, 2]});
+
+// Build.
+execSync(`npm run build`, {cwd: blocklyNodeModulesPath, stdio: [0, 1, 2]});
+
+// Package.
+execSync(`npm run package`, {cwd: blocklyNodeModulesPath, stdio: [0, 1, 2]});