feat(core): add dynamic queries schematic

Adds a schematic that will remove the explicit `static: false` flag from dynamic queries. E.g.

#### Before
```ts
import { Directive, ViewChild, ContentChild, ElementRef } from '@angular/core';

@directive()
export class MyDirective {
  @ViewChild('child', { static: false }) child: any;
  @ViewChild('secondChild', { read: ElementRef, static: false }) secondChild: ElementRef;
  @ContentChild('thirdChild', { static: false }) thirdChild: any;
}
```

#### After
```ts
import { Directive, ViewChild, ContentChild, ElementRef } from '@angular/core';

@directive()
export class MyDirective {
  @ViewChild('child') child: any;
  @ViewChild('secondChild', { read: ElementRef }) secondChild: ElementRef;
  @ContentChild('thirdChild') thirdChild: any;
}
```

packages/core/schematics/BUILD.bazel

@@ -10,6 +10,7 @@ npm_package(
     srcs = ["migrations.json"],
     visibility = ["//packages/core:__pkg__"],
     deps = [
+        "//packages/core/schematics/migrations/dynamic-queries",
         "//packages/core/schematics/migrations/move-document",
         "//packages/core/schematics/migrations/renderer-to-renderer2",
         "//packages/core/schematics/migrations/static-queries",

packages/core/schematics/migrations.json

@@ -24,6 +24,11 @@
       "version": "9-beta",
       "description": "Decorates undecorated base classes of directives/components that use dependency injection. Copies metadata from base classes to derived directives/components/pipes that are not decorated.",
       "factory": "./migrations/undecorated-classes-with-di/index"
+    },
+    "migration-v9-dynamic-queries": {
+      "version": "9-beta",
+      "description": "Removes the `static` flag from dynamic queries.",
+      "factory": "./migrations/dynamic-queries/index"
     }
   }
 }

packages/core/schematics/migrations/dynamic-queries/BUILD.bazel

@@ -0,0 +1,18 @@
+load("//tools:defaults.bzl", "ts_library")
+
+ts_library(
+    name = "dynamic-queries",
+    srcs = glob(["**/*.ts"]),
+    tsconfig = "//packages/core/schematics:tsconfig.json",
+    visibility = [
+        "//packages/core/schematics:__pkg__",
+        "//packages/core/schematics/migrations/google3:__pkg__",
+        "//packages/core/schematics/test:__pkg__",
+    ],
+    deps = [
+        "//packages/core/schematics/utils",
+        "@npm//@angular-devkit/schematics",
+        "@npm//@types/node",
+        "@npm//typescript",
+    ],
+)

packages/core/schematics/migrations/dynamic-queries/README.md

@@ -0,0 +1,27 @@
+## Dynamic queries migration
+
+Automatically migrates dynamic queries to remove their `static` flag.
+
+#### Before
+```ts
+import { Directive, ViewChild, ContentChild, ElementRef } from '@angular/core';
+
+@Directive()
+export class MyDirective {
+  @ViewChild('child', { static: false }) child: any;
+  @ViewChild('secondChild', { read: ElementRef, static: false }) secondChild: ElementRef;
+  @ContentChild('thirdChild', { static: false }) thirdChild: any;
+}
+```
+
+#### After
+```ts
+import { Directive, ViewChild, ContentChild, ElementRef } from '@angular/core';
+
+@Directive()
+export class MyDirective {
+  @ViewChild('child') child: any;
+  @ViewChild('secondChild', { read: ElementRef }) secondChild: ElementRef;
+  @ContentChild('thirdChild') thirdChild: any;
+}
+```

packages/core/schematics/migrations/dynamic-queries/index.ts

@@ -0,0 +1,84 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {Rule, SchematicsException, Tree} from '@angular-devkit/schematics';
+import {dirname, relative} from 'path';
+import * as ts from 'typescript';
+
+import {getProjectTsConfigPaths} from '../../utils/project_tsconfig_paths';
+import {parseTsconfigFile} from '../../utils/typescript/parse_tsconfig'
+import {identifyDynamicQueryNodes, removeOptionsParameter, removeStaticFlag} from './util';
+
+
+/**
+ * Runs a migration over a TypeScript project that removes
+ * the `static: false` flag from query annotations.
+ */
+export default function(): Rule {
+  return (tree: Tree) => {
+    const {buildPaths, testPaths} = getProjectTsConfigPaths(tree);
+    const basePath = process.cwd();
+    const allPaths = [...buildPaths, ...testPaths];
+
+    if (!allPaths.length) {
+      throw new SchematicsException(
+          'Could not find any tsconfig file. Cannot migrate dynamic queries.');
+    }
+
+    for (const tsconfigPath of allPaths) {
+      runDynamicQueryMigration(tree, tsconfigPath, basePath);
+    }
+  };
+}
+
+function runDynamicQueryMigration(tree: Tree, tsconfigPath: string, basePath: string) {
+  const parsed = parseTsconfigFile(tsconfigPath, dirname(tsconfigPath));
+  const host = ts.createCompilerHost(parsed.options, true);
+
+  // We need to overwrite the host "readFile" method, as we want the TypeScript
+  // program to be based on the file contents in the virtual file tree. Otherwise
+  // if we run the migration for multiple tsconfig files which have intersecting
+  // source files, it can end up updating query definitions multiple times.
+  host.readFile = fileName => {
+    const buffer = tree.read(relative(basePath, fileName));
+    // Strip BOM as otherwise TSC methods (Ex: getWidth) will return an offset which
+    // which breaks the CLI UpdateRecorder.
+    // See: https://github.com/angular/angular/pull/30719
+    return buffer ? buffer.toString().replace(/^\uFEFF/, '') : undefined;
+  };
+
+  const program = ts.createProgram(parsed.fileNames, parsed.options, host);
+  const typeChecker = program.getTypeChecker();
+  const sourceFiles = program.getSourceFiles().filter(
+      f => !f.isDeclarationFile && !program.isSourceFileFromExternalLibrary(f));
+  const printer = ts.createPrinter();
+
+  sourceFiles.forEach(sourceFile => {
+    const result = identifyDynamicQueryNodes(typeChecker, sourceFile);
+
+    if (result.removeProperty.length || result.removeParameter.length) {
+      const update = tree.beginUpdate(relative(basePath, sourceFile.fileName));
+
+      result.removeProperty.forEach(node => {
+        update.remove(node.getStart(), node.getWidth());
+        update.insertRight(
+            node.getStart(),
+            printer.printNode(ts.EmitHint.Unspecified, removeStaticFlag(node), sourceFile));
+      });
+
+      result.removeParameter.forEach(node => {
+        update.remove(node.getStart(), node.getWidth());
+        update.insertRight(
+            node.getStart(),
+            printer.printNode(ts.EmitHint.Unspecified, removeOptionsParameter(node), sourceFile));
+      });
+
+      tree.commitUpdate(update);
+    }
+  });
+}

packages/core/schematics/migrations/dynamic-queries/util.ts

@@ -0,0 +1,77 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import * as ts from 'typescript';
+import {getAngularDecorators} from '../../utils/ng_decorators';
+
+/**
+ * Identifies the nodes that should be migrated by the dynamic
+ * queries schematic. Splits the nodes into the following categories:
+ * - `removeProperty` - queries from which we should only remove the `static` property of the
+ *  `options` parameter (e.g. `@ViewChild('child', {static: false, read: ElementRef})`).
+ * - `removeParameter` - queries from which we should drop the entire `options` parameter.
+ *  (e.g. `@ViewChild('child', {static: false})`).
+ */
+export function identifyDynamicQueryNodes(typeChecker: ts.TypeChecker, sourceFile: ts.SourceFile) {
+  const removeProperty: ts.ObjectLiteralExpression[] = [];
+  const removeParameter: ts.CallExpression[] = [];
+
+  sourceFile.forEachChild(function walk(node: ts.Node) {
+    if (ts.isClassDeclaration(node)) {
+      node.members.forEach(member => {
+        const angularDecorators =
+            member.decorators && getAngularDecorators(typeChecker, member.decorators);
+
+        if (angularDecorators) {
+          angularDecorators
+              // Filter out the queries that can have the `static` flag.
+              .filter(decorator => {
+                return decorator.name === 'ViewChild' || decorator.name === 'ContentChild';
+              })
+              // Filter out the queries where the `static` flag is explicitly set to `false`.
+              .filter(decorator => {
+                const options = decorator.node.expression.arguments[1];
+                return options && ts.isObjectLiteralExpression(options) &&
+                    options.properties.some(
+                        property => ts.isPropertyAssignment(property) &&
+                            property.initializer.kind === ts.SyntaxKind.FalseKeyword);
+              })
+              .forEach(decorator => {
+                const options =
+                    decorator.node.expression.arguments[1] as ts.ObjectLiteralExpression;
+
+                // At this point we know that at least one property is the `static` flag. If this is
+                // the only property we can drop the entire object literal, otherwise we have to
+                // drop only the property.
+                if (options.properties.length === 1) {
+                  removeParameter.push(decorator.node.expression);
+                } else {
+                  removeProperty.push(options);
+                }
+              });
+        }
+      });
+    }
+
+    node.forEachChild(walk);
+  });
+
+  return {removeProperty, removeParameter};
+}
+
+/** Removes the `options` parameter from the call expression of a query decorator. */
+export function removeOptionsParameter(node: ts.CallExpression): ts.CallExpression {
+  return ts.updateCall(node, node.expression, node.typeArguments, [node.arguments[0]]);
+}
+
+/** Removes the `static` property from an object literal expression. */
+export function removeStaticFlag(node: ts.ObjectLiteralExpression): ts.ObjectLiteralExpression {
+  return ts.updateObjectLiteral(
+      node,
+      node.properties.filter(property => property.name && property.name.getText() !== 'static'));
+}

packages/core/schematics/migrations/google3/BUILD.bazel

@@ -6,6 +6,7 @@ ts_library(
     tsconfig = "//packages/core/schematics:tsconfig.json",
     visibility = ["//packages/core/schematics/test/google3:__pkg__"],
     deps = [
+        "//packages/core/schematics/migrations/dynamic-queries",
         "//packages/core/schematics/migrations/missing-injectable",
         "//packages/core/schematics/migrations/missing-injectable/google3",
         "//packages/core/schematics/migrations/renderer-to-renderer2",

packages/core/schematics/migrations/google3/dynamicQueriesRule.ts

@@ -0,0 +1,45 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {Replacement, RuleFailure, Rules} from 'tslint';
+import * as ts from 'typescript';
+
+import {identifyDynamicQueryNodes, removeOptionsParameter, removeStaticFlag} from '../dynamic-queries/util';
+
+const RULE_NAME = 'dynamic-queries';
+const FAILURE_MESSAGE = 'Static flag on queries is no longer required.';
+
+/**
+ * TSLint rule that removes the `static` flag from dynamic queries.
+ */
+export class Rule extends Rules.TypedRule {
+  applyWithProgram(sourceFile: ts.SourceFile, program: ts.Program): RuleFailure[] {
+    const printer = ts.createPrinter();
+    const failures: RuleFailure[] = [];
+    const result = identifyDynamicQueryNodes(program.getTypeChecker(), sourceFile);
+
+    result.removeProperty.forEach(node => {
+      failures.push(new RuleFailure(
+          sourceFile, node.getStart(), node.getEnd(), FAILURE_MESSAGE, RULE_NAME,
+          new Replacement(
+              node.getStart(), node.getWidth(),
+              printer.printNode(ts.EmitHint.Unspecified, removeStaticFlag(node), sourceFile))));
+    });
+
+    result.removeParameter.forEach(node => {
+      failures.push(new RuleFailure(
+          sourceFile, node.getStart(), node.getEnd(), FAILURE_MESSAGE, RULE_NAME,
+          new Replacement(
+              node.getStart(), node.getWidth(),
+              printer.printNode(
+                  ts.EmitHint.Unspecified, removeOptionsParameter(node), sourceFile))));
+    });
+
+    return failures;
+  }
+}

packages/core/schematics/test/BUILD.bazel

@@ -9,6 +9,7 @@ ts_library(
         "//packages/core/schematics:migrations.json",
     ],
     deps = [
+        "//packages/core/schematics/migrations/dynamic-queries",
         "//packages/core/schematics/migrations/missing-injectable",
         "//packages/core/schematics/migrations/move-document",
         "//packages/core/schematics/migrations/renderer-to-renderer2",