Updates

Author: devversion

scripts/install-angular-snapshots.js

@@ -4,25 +4,39 @@
  * would complain about outdated lock files.
  */
 
-const join = require('path').join;
+const path = require('path');
+const fs = require('fs');
 const execSync = require('child_process').execSync;
-const packageJson = require('../package.json');
+const packageJsonPath = path.join(__dirname, '../package.json');
+const packageJson = require(packageJsonPath);
 
-// List of Angular packages that are specified in the "package.json". Packages will be listed
-// without the "@angular/" scope.
-const angularPackages = Object
-  .keys({...packageJson.dependencies, ...packageJson.devDependencies})
-  .filter(depName => depName.startsWith('@angular/'))
-  .map(depName => depName.split('/').slice(1));
+/** 
+ * Updates all Angular dependencies for a given type by replacing the version with a Github URL
+ * that refers to the corresponding Github builds repository.
+ * @param dependencyType Either `dependencies` or `devDependencies` 
+*/
+function updateAngularDependencies(dependencyType) {
+  Object.keys(packageJson[dependencyType])
+    .filter(depName => depName.startsWith('@angular/'))
+    .forEach(depName => {
+      packageJson[dependencyType][depName] = `github:angular/${depName.split('/')[1]}-builds`
+    });
+}
 
-// List of URLs that refer to the Github snapshot builds for all Angular packages.
-const githubBuildUrls = angularPackages.map(name => `github:angular/${name}-builds`);
+// Update `dependencies` and `devDependencies` in the "packageJson" object, so that
+// we can write the changes to disk afterwards. We cannot just run `yarn add ${all_deps}` because
+// Yarn will complain that some dependencies are already set up in the package.json file.
+updateAngularDependencies('dependencies');
+updateAngularDependencies('devDependencies');
 
-// Run yarn add {URLs}, so that it replaces the Angular npm packages with the Github builds.
-execSync(`yarn add ${githubBuildUrls.join(' ')}`, {
+// Write the dependencies changes to the original "package.json" file.
+fs.writeFileSync(packageJsonPath, JSON.stringify(packageJson, null, 2));
+
+// Run "yarn install" in order to install the packages that have been written to the package.json.
+execSync('yarn install', {
   stdio: 'inherit',
   shell: true,
-  cwd: join(__dirname, '../')
+  cwd: path.join(__dirname, '../')
 });
 
 console.log('Finished installing the Angular snapshot builds.');