test(@schematics/angular): refactor tailwind schematic tests for clarity

The tests for the Tailwind schematic have been refactored to improve readability and reduce boilerplate code.

Helper functions (`createTestApp`, `getWorkspace`) have been introduced to handle the repetitive setup of the test application and the parsing of the workspace configuration. The existing tests were updated to use these new helpers, making them more concise and easier to maintain.

Author: clydin

packages/schematics/angular/tailwind/index_spec.ts

@@ -10,18 +10,31 @@ import { SchematicTestRunner, UnitTestTree } from '@angular-devkit/schematics/te
 import { Schema as ApplicationOptions, Style } from '../application/schema';
 import { Schema as WorkspaceOptions } from '../workspace/schema';
 
-describe('Tailwind Schematic', () => {
-  const schematicRunner = new SchematicTestRunner(
-    '@schematics/angular',
-    require.resolve('../collection.json'),
-  );
-
+async function createTestApp(
+  runner: SchematicTestRunner,
+  appOptions: ApplicationOptions,
+  style = Style.Css,
+): Promise<UnitTestTree> {
   const workspaceOptions: WorkspaceOptions = {
     name: 'workspace',
     newProjectRoot: 'projects',
     version: '6.0.0',
   };
 
+  let appTree = await runner.runSchematic('workspace', workspaceOptions);
+  return runner.runSchematic('application', { ...appOptions, style }, appTree);
+}
+
+function getWorkspace(tree: UnitTestTree): any {
+  return JSON.parse(tree.readContent('/angular.json'));
+}
+
+describe('Tailwind Schematic', () => {
+  const schematicRunner = new SchematicTestRunner(
+    '@schematics/angular',
+    require.resolve('../collection.json'),
+  );
+
   const appOptions: ApplicationOptions = {
     name: 'bar',
     inlineStyle: false,
@@ -35,8 +48,7 @@ describe('Tailwind Schematic', () => {
   let appTree: UnitTestTree;
 
   beforeEach(async () => {
-    appTree = await schematicRunner.runSchematic('workspace', workspaceOptions);
-    appTree = await schematicRunner.runSchematic('application', appOptions, appTree);
+    appTree = await createTestApp(schematicRunner, appOptions);
   });
 
   it('should add tailwind dependencies', async () => {
@@ -47,17 +59,6 @@ describe('Tailwind Schematic', () => {
     expect(packageJson.devDependencies['@tailwindcss/postcss']).toBeDefined();
   });
 
-  it('should create a .postcssrc.json file in the project root', async () => {
-    const tree = await schematicRunner.runSchematic('tailwind', { project: 'bar' }, appTree);
-    expect(tree.exists('/projects/bar/.postcssrc.json')).toBe(true);
-  });
-
-  it('should configure tailwindcss plugin in .postcssrc.json', async () => {
-    const tree = await schematicRunner.runSchematic('tailwind', { project: 'bar' }, appTree);
-    const postCssConfig = JSON.parse(tree.readContent('/projects/bar/.postcssrc.json'));
-    expect(postCssConfig.plugins['@tailwindcss/postcss']).toBeDefined();
-  });
-
   it('should add tailwind imports to styles.css', async () => {
     const tree = await schematicRunner.runSchematic('tailwind', { project: 'bar' }, appTree);
     const stylesContent = tree.readContent('/projects/bar/src/styles.css');
@@ -76,12 +77,7 @@ describe('Tailwind Schematic', () => {
 
   describe('with scss styles', () => {
     beforeEach(async () => {
-      appTree = await schematicRunner.runSchematic('workspace', workspaceOptions);
-      appTree = await schematicRunner.runSchematic(
-        'application',
-        { ...appOptions, style: Style.Scss },
-        appTree,
-      );
+      appTree = await createTestApp(schematicRunner, appOptions, Style.Scss);
     });
 
     it('should create a tailwind.css file', async () => {
@@ -93,8 +89,8 @@ describe('Tailwind Schematic', () => {
 
     it('should add tailwind.css to angular.json', async () => {
       const tree = await schematicRunner.runSchematic('tailwind', { project: 'bar' }, appTree);
-      const angularJson = JSON.parse(tree.readContent('/angular.json'));
-      const styles = angularJson.projects.bar.architect.build.options.styles;
+      const workspace = getWorkspace(tree);
+      const styles = workspace.projects.bar.architect.build.options.styles;
       expect(styles).toEqual(['projects/bar/src/tailwind.css', 'projects/bar/src/styles.scss']);
     });