From 762c9ee50d6d173f73bc5a701d533081155b270f Mon Sep 17 00:00:00 2001
From: Colum Ferry <cferry09@gmail.com>
Date: Wed, 4 Jan 2023 11:04:53 +0000
Subject: [PATCH] feat(angular): add isStandalone util to check for standalone
 decorators (#14129)

---
 .../src/utils/nx-devkit/ast-utils.spec.ts     | 109 ++++++++++++++++++
 .../angular/src/utils/nx-devkit/ast-utils.ts  |  18 ++-
 2 files changed, 126 insertions(+), 1 deletion(-)

diff --git a/packages/angular/src/utils/nx-devkit/ast-utils.spec.ts b/packages/angular/src/utils/nx-devkit/ast-utils.spec.ts
index c26ff6c147..f438acd2cf 100644
--- a/packages/angular/src/utils/nx-devkit/ast-utils.spec.ts
+++ b/packages/angular/src/utils/nx-devkit/ast-utils.spec.ts
@@ -3,6 +3,7 @@ import {
   addImportToDirective,
   addImportToModule,
   addImportToPipe,
+  isStandalone,
 } from './ast-utils';
 import { createTreeWithEmptyWorkspace } from '@nrwl/devkit/testing';
 import { createSourceFile, ScriptTarget } from 'typescript';
@@ -151,4 +152,112 @@ describe('Angular AST Utils', () => {
           "
     `);
   });
+
+  it('should allow checking if a component is standalone and return true if so', () => {
+    // ARRANGE
+    const tree = createTreeWithEmptyWorkspace();
+    const pathToFile = `my.component.ts`;
+    const originalContents = `import { Component } from '@angular/core';
+    
+    @Component({
+      standalone: true
+    })
+    export class MyComponent {}
+    `;
+
+    tree.write(pathToFile, originalContents);
+
+    const sourceText = tree.read(pathToFile, 'utf-8');
+    const tsSourceFile = createSourceFile(
+      pathToFile,
+      sourceText,
+      ScriptTarget.Latest,
+      true
+    );
+
+    // ACT
+    // ASSERT
+    expect(isStandalone(tsSourceFile, 'Component')).toBeTruthy();
+  });
+
+  it('should allow checking if a component is standalone and return false if not', () => {
+    // ARRANGE
+    const tree = createTreeWithEmptyWorkspace();
+    const pathToFile = `my.component.ts`;
+    const originalContents = `import { Component } from '@angular/core';
+    
+    @Component({
+      standalone: false
+    })
+    export class MyComponent {}
+    `;
+
+    tree.write(pathToFile, originalContents);
+
+    const sourceText = tree.read(pathToFile, 'utf-8');
+    const tsSourceFile = createSourceFile(
+      pathToFile,
+      sourceText,
+      ScriptTarget.Latest,
+      true
+    );
+
+    // ACT
+    // ASSERT
+    expect(isStandalone(tsSourceFile, 'Component')).not.toBeTruthy();
+  });
+
+  it('should allow checking if a directive is standalone and return true if so', () => {
+    // ARRANGE
+    const tree = createTreeWithEmptyWorkspace();
+    const pathToFile = `my.directive.ts`;
+    const originalContents = `import { Directive } from '@angular/core';
+    
+    @Directive({
+      standalone: true
+    })
+    export class MyDirective {}
+    `;
+
+    tree.write(pathToFile, originalContents);
+
+    const sourceText = tree.read(pathToFile, 'utf-8');
+    const tsSourceFile = createSourceFile(
+      pathToFile,
+      sourceText,
+      ScriptTarget.Latest,
+      true
+    );
+
+    // ACT
+    // ASSERT
+    expect(isStandalone(tsSourceFile, 'Directive')).toBeTruthy();
+  });
+
+  it('should allow checking if a pipe is standalone and return true if so', () => {
+    // ARRANGE
+    const tree = createTreeWithEmptyWorkspace();
+    const pathToFile = `my.pipe.ts`;
+    const originalContents = `import { Pipe } from '@angular/core';
+    
+    @Pipe({
+      standalone: true
+    })
+    export class MyPipe {}
+    `;
+
+    tree.write(pathToFile, originalContents);
+
+    const sourceText = tree.read(pathToFile, 'utf-8');
+    const tsSourceFile = createSourceFile(
+      pathToFile,
+      sourceText,
+      ScriptTarget.Latest,
+      true
+    );
+
+    // ACT
+    // ASSERT
+    expect(isStandalone(tsSourceFile, 'Pipe')).toBeTruthy();
+  });
 });
diff --git a/packages/angular/src/utils/nx-devkit/ast-utils.ts b/packages/angular/src/utils/nx-devkit/ast-utils.ts
index 079cda7a4c..9e4dc05a79 100644
--- a/packages/angular/src/utils/nx-devkit/ast-utils.ts
+++ b/packages/angular/src/utils/nx-devkit/ast-utils.ts
@@ -10,6 +10,8 @@ import {
   replaceChange,
 } from '@nrwl/workspace/src/utilities/ast-utils';
 
+type DecoratorName = 'Component' | 'Directive' | 'NgModule' | 'Pipe';
+
 function _angularImportsFromNode(
   node: ts.ImportDeclaration,
   _sourceFile: ts.SourceFile
@@ -62,6 +64,20 @@ function _angularImportsFromNode(
   }
 }
 
+export function isStandalone(
+  sourceFile: ts.SourceFile,
+  decoratorName: DecoratorName
+) {
+  const decoratorMetadata = getDecoratorMetadata(
+    sourceFile,
+    decoratorName,
+    '@angular/core'
+  );
+  return decoratorMetadata.some((node) =>
+    node.getText().includes('standalone: true')
+  );
+}
+
 export function getDecoratorMetadata(
   source: ts.SourceFile,
   identifier: string,
@@ -134,7 +150,7 @@ function _addSymbolToDecoratorMetadata(
   filePath: string,
   metadataField: string,
   expression: string,
-  decoratorName: 'Component' | 'Directive' | 'NgModule' | 'Pipe'
+  decoratorName: DecoratorName
 ): ts.SourceFile {
   const nodes = getDecoratorMetadata(source, decoratorName, '@angular/core');
   let node: any = nodes[0]; // tslint:disable-line:no-any