refactor(language-service): clean up and exports and consolidate types (#36533)

PR Close #36533

packages/language-service/test/utils_spec.ts

@@ -9,7 +9,8 @@
 import * as ng from '@angular/compiler';
 import * as ts from 'typescript';
 
-import {getDirectiveClassLike, getPathToNodeAtPosition} from '../src/utils';
+import {getClassDeclFromDecoratorProp, getDirectiveClassLike, getPathToNodeAtPosition} from '../src/utils';
+import {MockTypescriptHost} from './test_utils';
 
 describe('getDirectiveClassLike', () => {
   it('should return a directive class', () => {
@@ -80,3 +81,42 @@ describe('getPathToNodeAtPosition', () => {
     expect(path.tail instanceof ng.Attribute).toBe(true);
   });
 });
+
+describe('getClassDeclFromTemplateNode', () => {
+  it('should find class declaration in syntax-only mode', () => {
+    const sourceFile = ts.createSourceFile(
+        'foo.ts', `
+        @Component({
+          template: '<div></div>'
+        })
+        class MyComponent {}`,
+        ts.ScriptTarget.ES2015, true /* setParentNodes */);
+    function visit(node: ts.Node): ts.ClassDeclaration|undefined {
+      if (ts.isPropertyAssignment(node)) {
+        return getClassDeclFromDecoratorProp(node);
+      }
+      return node.forEachChild(visit);
+    }
+    const classDecl = sourceFile.forEachChild(visit);
+    expect(classDecl).toBeTruthy();
+    expect(classDecl!.kind).toBe(ts.SyntaxKind.ClassDeclaration);
+    expect((classDecl as ts.ClassDeclaration).name!.text).toBe('MyComponent');
+  });
+
+
+  it('should return class declaration for AppComponent', () => {
+    const host = new MockTypescriptHost(['/app/app.component.ts']);
+    const tsLS = ts.createLanguageService(host);
+    const sourceFile = tsLS.getProgram()!.getSourceFile('/app/app.component.ts');
+    expect(sourceFile).toBeTruthy();
+    const classDecl = sourceFile!.forEachChild(function visit(node): ts.Node|undefined {
+      if (ts.isPropertyAssignment(node)) {
+        return getClassDeclFromDecoratorProp(node);
+      }
+      return node.forEachChild(visit);
+    });
+    expect(classDecl).toBeTruthy();
+    expect(ts.isClassDeclaration(classDecl!)).toBe(true);
+    expect((classDecl as ts.ClassDeclaration).name!.text).toBe('AppComponent');
+  });
+});