fix(@schematics/update): stabilize package list before continuing

Fix angular/angular-cli#10875

packages/schematics/update/update/index.ts

@@ -790,10 +790,16 @@ export default function(options: UpdateSchema): Rule {
 
       map(npmPackageJsonMap => {
         // Augment the command line package list with packageGroups and forward peer dependencies.
-        npmPackageJsonMap.forEach((npmPackageJson) => {
-          _addPackageGroup(packages, allDependencies, npmPackageJson, logger);
-          _addPeerDependencies(packages, allDependencies, npmPackageJson, logger);
-        });
+        // Each added package may uncover new package groups and peer dependencies, so we must
+        // repeat this process until the package list stabilizes.
+        let lastPackagesSize;
+        do {
+          lastPackagesSize = packages.size;
+          npmPackageJsonMap.forEach((npmPackageJson) => {
+            _addPackageGroup(packages, allDependencies, npmPackageJson, logger);
+            _addPeerDependencies(packages, allDependencies, npmPackageJson, logger);
+          });
+        } while (packages.size > lastPackagesSize);
 
         // Build the PackageInfo for each module.
         const packageInfoMap = new Map<string, PackageInfo>();

packages/schematics/update/update/index_spec.ts

@@ -161,9 +161,11 @@ describe('@schematics/update', () => {
     dependencies['@angular/animations'] = '5.1.0';
     dependencies['@angular/common'] = '5.1.0';
     dependencies['@angular/compiler'] = '5.1.0';
+    dependencies['@angular/compiler-cli'] = '5.1.0';
     dependencies['@angular/platform-browser'] = '5.1.0';
     dependencies['rxjs'] = '5.5.0';
     dependencies['zone.js'] = '0.8.26';
+    dependencies['typescript'] = '2.4.2';
     host.sync.write(
       normalize('/package.json'),
       virtualFs.stringToFileBuffer(JSON.stringify(packageJson)),
@@ -176,6 +178,9 @@ describe('@schematics/update', () => {
       map(tree => {
         const packageJson = JSON.parse(tree.readContent('/package.json'));
         expect(packageJson['dependencies']['@angular/core'][0]).toBe('6');
+        expect(packageJson['dependencies']['rxjs'][0]).toBe('6');
+        expect(packageJson['dependencies']['typescript'][0]).toBe('2');
+        expect(packageJson['dependencies']['typescript'][2]).toBe('7');
 
         // Check install task.
         expect(schematicRunner.tasks).toEqual([