build(docs-infra): separate NgModules from Classes in API docs (#25734)

PR Close #25734

aio/tools/transforms/angular-api-package/processors/extractDecoratedClasses.js

@@ -8,7 +8,7 @@ module.exports = function extractDecoratedClassesProcessor(EXPORT_DOC_TYPES) {
   return {
     $runAfter: ['processing-docs'],
     $runBefore: ['docs-processed'],
-    decoratorTypes: ['Directive', 'Component', 'Pipe'],
+    decoratorTypes: ['Directive', 'Component', 'Pipe', 'NgModule'],
     $process: function(docs) {
       var decoratorTypes = this.decoratorTypes;
 

aio/tools/transforms/angular-api-package/processors/processNgModuleDocs.js

@@ -0,0 +1,18 @@
+module.exports = function processNgModuleDocs() {
+  return {
+    $runAfter: ['extractDecoratedClassesProcessor'],
+    $runBefore: ['docs-processed'],
+    $process(docs) {
+      docs.forEach(doc => {
+        if (doc.docType === 'ngmodule') {
+          Object.keys(doc.ngmoduleOptions).forEach(key => {
+            const value = doc.ngmoduleOptions[key];
+            if (value && !Array.isArray(value)) {
+              doc.ngmoduleOptions[key] = [value];
+            }
+          });
+        }
+      });
+    }
+  };
+};

aio/tools/transforms/angular-api-package/processors/processNgModuleDocs.spec.js

@@ -0,0 +1,24 @@
+const testPackage = require('../../helpers/test-package');
+const Dgeni = require('dgeni');
+
+describe('processNgModuleDocs processor', () => {
+  let processor;
+  beforeEach(() => {
+    const dgeni = new Dgeni([testPackage('angular-api-package')]);
+    const injector = dgeni.configureInjector();
+    processor = injector.get('processNgModuleDocs');
+  });
+
+  it('should be available on the injector', () => {
+    expect(processor.$process).toBeDefined();
+  });
+
+  it('should run before the correct processor', () => {
+    expect(processor.$runBefore).toEqual(['docs-processed']);
+  });
+
+  it('should run after the correct processor', () => {
+    expect(processor.$runAfter).toEqual(['extractDecoratedClassesProcessor']);
+  });
+
+});