refactor(schematics): do not depend on parse5 twice (#13594)

* As we've already moved the ng-update foundation to the CDK, and therefore introduced an `optionalDependency` on `parse5` for the CDK, we should also move the last `parse5` call from `@angular/material` to the `@angular/cdk`. This way we don't depend on `parse5` for both packages + we can re-use the abstract utility function within the CDK schematics if we need them.

* The `parse5` runtime check is actually not working because NodeJS would throw already if we just `require("parse5")`. Since we marked `parse5` as a dependency and the default NodeJS `module not found` message is clear enough, we can remove this check from the `ng-add` command as well.

src/cdk/schematics/utils/html-head-element.ts

@@ -6,32 +6,28 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {WorkspaceProject} from '@angular-devkit/core/src/workspace';
 import {SchematicsException, Tree} from '@angular-devkit/schematics';
-import {getChildElementIndentation} from '@angular/cdk/schematics';
+import {getChildElementIndentation} from './parse5-element';
 import {DefaultTreeDocument, DefaultTreeElement, parse as parseHtml} from 'parse5';
-import {getIndexHtmlPath} from './project-index-html';
 
+/** Appends the given element HTML fragment to the `<head>` element of the specified HTML file. */
+export function appendHtmlElementToHead(host: Tree, htmlFilePath: string, elementHtml: string) {
+  const htmlFileBuffer = host.read(htmlFilePath);
 
-/** Appends the given element HTML fragment to the index.html head tag. */
-export function appendElementToHead(host: Tree, project: WorkspaceProject, elementHtml: string) {
-  const indexPath = getIndexHtmlPath(project);
-  const indexHtmlBuffer = host.read(indexPath);
-
-  if (!indexHtmlBuffer) {
-    throw new SchematicsException(`Could not find file for path: ${indexPath}`);
+  if (!htmlFileBuffer) {
+    throw new SchematicsException(`Could not read file for path: ${htmlFilePath}`);
   }
 
-  const htmlContent = indexHtmlBuffer.toString();
+  const htmlContent = htmlFileBuffer.toString();
 
   if (htmlContent.includes(elementHtml)) {
     return;
   }
 
-  const headTag = getHeadTagElement(htmlContent);
+  const headTag = getHtmlHeadTagElement(htmlContent);
 
   if (!headTag) {
-    throw `Could not find '<head>' element in HTML file: ${indexPath}`;
+    throw `Could not find '<head>' element in HTML file: ${htmlFileBuffer}`;
   }
 
   // We always have access to the source code location here because the `getHeadTagElement`
@@ -41,15 +37,15 @@ export function appendElementToHead(host: Tree, project: WorkspaceProject, eleme
   const insertion = `${' '.repeat(indentationOffset)}${elementHtml}`;
 
   const recordedChange = host
-    .beginUpdate(indexPath)
+    .beginUpdate(htmlFilePath)
     .insertRight(endTagOffset, `${insertion}\n`);
 
   host.commitUpdate(recordedChange);
 }
 
 /** Parses the given HTML file and returns the head element if available. */
-export function getHeadTagElement(src: string): DefaultTreeElement | null {
-  const document = parseHtml(src, {sourceCodeLocationInfo: true}) as DefaultTreeDocument;
+export function getHtmlHeadTagElement(htmlContent: string): DefaultTreeElement | null {
+  const document = parseHtml(htmlContent, {sourceCodeLocationInfo: true}) as DefaultTreeDocument;
   const nodeQueue = [...document.childNodes];
 
   while (nodeQueue.length) {

src/cdk/schematics/utils/index.ts

@@ -10,6 +10,7 @@ export * from './ast';
 export * from './ast/ng-module-imports';
 export * from './build-component';
 export * from './get-project';
+export * from './html-head-element';
 export * from './parse5-element';
 export * from './project-main-file';
 export * from './project-style-file';

src/lib/package.json

@@ -30,9 +30,6 @@
   "dependencies": {
     "tslib": "^1.7.1"
   },
-  "optionalDependencies": {
-    "parse5": "^5.0.0"
-  },
   "schematics": "./schematics/collection.json",
   "ng-update": {
     "migrations": "./schematics/migration.json",

src/lib/schematics/BUILD.bazel

@@ -25,7 +25,6 @@ ts_library(
     # TODO(devversion): Only include jasmine for test sources (See: tsconfig types).
     "@npm//@types/jasmine",
     "@npm//@types/node",
-    "@npm//parse5",
     "@npm//tslint",
     "@npm//typescript",
   ],

src/lib/schematics/ng-add/fonts/material-fonts.ts

@@ -7,23 +7,26 @@
  */
 
 import {Tree} from '@angular-devkit/schematics';
-import {getProjectFromWorkspace} from '@angular/cdk/schematics';
+import {appendHtmlElementToHead, getProjectFromWorkspace} from '@angular/cdk/schematics';
 import {getWorkspace} from '@schematics/angular/utility/config';
 import {Schema} from '../schema';
-import {appendElementToHead} from './head-element';
+import {getIndexHtmlPath} from './project-index-html';
 
 /** Adds the Material Design fonts to the index HTML file. */
 export function addFontsToIndex(options: Schema): (host: Tree) => Tree {
   return (host: Tree) => {
     const workspace = getWorkspace(host);
     const project = getProjectFromWorkspace(workspace, options.project);
+    const projectIndexHtmlPath = getIndexHtmlPath(project);
 
     const fonts = [
       'https://fonts.googleapis.com/css?family=Roboto:300,400,500',
       'https://fonts.googleapis.com/icon?family=Material+Icons',
     ];
 
-    fonts.forEach(f => appendElementToHead(host, project, `<link href="${f}" rel="stylesheet">`));
+    fonts.forEach(f => {
+      appendHtmlElementToHead(host, projectIndexHtmlPath, `<link href="${f}" rel="stylesheet">`);
+    });
 
     return host;
   };

src/lib/schematics/ng-add/setup-project.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {chain, noop, Rule, SchematicsException, Tree} from '@angular-devkit/schematics';
+import {chain, noop, Rule, Tree} from '@angular-devkit/schematics';
 import {
   addModuleImportToRootModule,
   getProjectFromWorkspace,
@@ -17,7 +17,6 @@ import {
 import {red, bold} from 'chalk';
 import {getWorkspace} from '@schematics/angular/utility/config';
 import {getAppModulePath} from '@schematics/angular/utility/ng-ast-utils';
-import * as parse5 from 'parse5';
 import {addFontsToIndex} from './fonts/material-fonts';
 import {addHammerJsToMain} from './gestures/hammerjs-import';
 import {Schema} from './schema';
@@ -36,11 +35,6 @@ const noopAnimationsModuleName = 'NoopAnimationsModule';
  *  - Adds Browser Animation to app.module
  */
 export default function(options: Schema): Rule {
-  if (!parse5) {
-    throw new SchematicsException('Parse5 is required but could not be found! Please install ' +
-      '"parse5" manually in order to continue.');
-  }
-
   return chain([
     options && options.gestures ? addHammerJsToMain(options) : noop(),
     addAnimationsModule(options),