fix(bazel): Schematics should upgrade rxjs to 6.4.0 (#28841)

Since rxjs is no longer built from source in Bazel schematics, the
minimum version ought to be at least 6.4.0.

This commit adds function to bump the version in package.json.

PR Close #28841

packages/bazel/src/schematics/ng-add/index.ts

@@ -13,7 +13,7 @@ import {Rule, SchematicContext, SchematicsException, Tree, apply, applyTemplates
 import {getWorkspacePath} from '@schematics/angular/utility/config';
 import {findPropertyInAstObject, insertPropertyInAstObjectInOrder} from '@schematics/angular/utility/json-utils';
 import {validateProjectName} from '@schematics/angular/utility/validation';
-import {isJsonAstObject, removeKeyValueInAstObject as removeKeyValueInAstObject, replacePropertyInAstObject} from '../utility/json-utils';
+import {isJsonAstObject, removeKeyValueInAstObject, replacePropertyInAstObject} from '../utility/json-utils';
 import {Schema} from './schema';
 
 /**
@@ -257,6 +257,47 @@ function updateTsconfigJson(): Rule {
   };
 }
 
+/**
+ * @angular/bazel requires minimum version of rxjs to be 6.4.0. This function
+ * upgrades the version of rxjs in package.json if necessary.
+ */
+function upgradeRxjs() {
+  return (host: Tree, context: SchematicContext) => {
+    const packageJson = 'package.json';
+    if (!host.exists(packageJson)) {
+      throw new Error(`Could not find ${packageJson}`);
+    }
+    const content = host.read(packageJson).toString();
+    const jsonAst = parseJsonAst(content);
+    if (!isJsonAstObject(jsonAst)) {
+      throw new Error(`Failed to parse JSON for ${packageJson}`);
+    }
+    const deps = findPropertyInAstObject(jsonAst, 'dependencies');
+    if (!isJsonAstObject(deps)) {
+      throw new Error(`Failed to find dependencies in ${packageJson}`);
+    }
+    const rxjs = findPropertyInAstObject(deps, 'rxjs');
+    if (!rxjs) {
+      throw new Error(`Failed to find rxjs in dependencies of ${packageJson}`);
+    }
+    const value = rxjs.value as string;  // value can be version or range
+    const match = value.match(/(\d)+\.(\d)+.(\d)+$/);
+    if (match) {
+      const [_, major, minor] = match;
+      if (major < '6' || (major === '6' && minor < '4')) {
+        const recorder = host.beginUpdate(packageJson);
+        replacePropertyInAstObject(recorder, deps, 'rxjs', '~6.4.0');
+        host.commitUpdate(recorder);
+      }
+    } else {
+      context.logger.info(
+          'Could not determine version of rxjs. \n' +
+          'Please make sure that version is at least 6.4.0.');
+    }
+    return host;
+  };
+}
+
 export default function(options: Schema): Rule {
   return (host: Tree) => {
     validateProjectName(options.name);
@@ -270,6 +311,7 @@ export default function(options: Schema): Rule {
       updateAngularJsonToUseBazelBuilder(options),
       updateGitignore(),
       updateTsconfigJson(),
+      upgradeRxjs(),
     ]);
   };
 }

packages/bazel/src/schematics/ng-add/index_spec.ts

@@ -21,6 +21,7 @@ describe('ng-add schematic', () => {
       name: 'demo',
       dependencies: {
         '@angular/core': '1.2.3',
+        'rxjs': '~6.3.3',
       },
       devDependencies: {
         'typescript': '3.2.2',
@@ -198,4 +199,44 @@ describe('ng-add schematic', () => {
       }
     });
   });
+
+  describe('rxjs', () => {
+    const cases = [
+      // version|upgrade
+      ['6.3.3', true],
+      ['~6.3.3', true],
+      ['^6.3.3', true],
+      ['~6.3.11', true],
+      ['6.4.0', false],
+      ['~6.4.0', false],
+      ['~6.4.1', false],
+      ['6.5.0', false],
+      ['~6.5.0', false],
+      ['^6.5.0', false],
+      ['~7.0.1', false],
+    ];
+    for (const [version, upgrade] of cases) {
+      it(`should ${upgrade ? '' : 'not '}upgrade v${version}')`, () => {
+        host.overwrite('package.json', JSON.stringify({
+          name: 'demo',
+          dependencies: {
+            '@angular/core': '1.2.3',
+            'rxjs': version,
+          },
+          devDependencies: {
+            'typescript': '3.2.2',
+          },
+        }));
+        host = schematicRunner.runSchematic('ng-add', defaultOptions, host);
+        expect(host.files).toContain('/package.json');
+        const content = host.readContent('/package.json');
+        const json = JSON.parse(content);
+        if (upgrade) {
+          expect(json.dependencies.rxjs).toBe('~6.4.0');
+        } else {
+          expect(json.dependencies.rxjs).toBe(version);
+        }
+      });
+    }
+  });
 });