TypescriptAPIUtils.isClassInstanceOf: return true for same classes used in imported file

Author: davidkudera

packages/typescript-api-utils/classes/instanceOf.ts

@@ -11,10 +11,16 @@ export function isClassInstanceOf(classDeclaration: ts.ClassDeclaration, parentC
 		return true;
 	}
 
-	let parentClassSourceFile: ts.SourceFile = undefined;
-	function getParentClassSourceFile(): ts.SourceFile
-	{
-		return exists(parentClassSourceFile) ? parentClassSourceFile : parentClassSourceFile = lookupSourceFile(parentClass);
+	const classDeclarationSourceFile = lookupSourceFile(classDeclaration);
+	const parentClassSourceFile = lookupSourceFile(parentClass);
+
+	if (
+		classDeclarationSourceFile.fileName === parentClassSourceFile.fileName &&
+		exists(classDeclaration.name) &&
+		exists(parentClass.name) &&
+		(<ts.Identifier>classDeclaration.name).text === (<ts.Identifier>parentClass.name).text
+	) {
+		return true;
 	}
 
 	const parents = lookupDeepParentClasses(classDeclaration, compilerOptions, moduleResolutionHost);
@@ -36,9 +42,7 @@ export function isClassInstanceOf(classDeclaration: ts.ClassDeclaration, parentC
 			return false;
 		}
 
-		const parentSourceFile = getParentClassSourceFile();
-
-		if (parentSourceFile.fileName !== parent.sourceFile.fileName) {
+		if (parentClassSourceFile.fileName !== parent.sourceFile.fileName) {
 			return false;
 		}
 

packages/typescript-api-utils/tests/data/classes/instanceOf/valid_6.classA.ts

@@ -0,0 +1 @@
+export class A {}

packages/typescript-api-utils/tests/data/classes/instanceOf/valid_6.ts

@@ -0,0 +1,4 @@
+import {A} from './valid_6.classA';
+
+
+_(A);

packages/typescript-api-utils/tests/tests/classes/instanceOf.ts

@@ -1,4 +1,4 @@
-import {findNode, isClassInstanceOf as _isClassInstanceOf, fsModuleResolutionHost} from '../../../';
+import {findNode, isClassInstanceOf as _isClassInstanceOf, fsModuleResolutionHost, resolveIdentifier} from '../../../';
 import {expect} from 'chai';
 import * as ts from 'typescript';
 import * as path from 'path';
@@ -68,6 +68,16 @@ describe('#classes/instanceOf', () => {
 			expect(isClassInstanceOf(classA, classA)).to.be.equal(true);
 		});
 
+		it('should return true when test class is same as testing class used from imported file', () => {
+			const sourceFile = getSourceFile('valid_6');
+			const sourceFileA = getSourceFile('valid_6.classA');
+			const nodeA = findNode<ts.Identifier>(ts.SyntaxKind.Identifier, 'A', sourceFile);
+			const classA = findNode<ts.ClassDeclaration>(ts.SyntaxKind.ClassDeclaration, 'A', sourceFileA);
+			const resolvedNodeA = resolveIdentifier<ts.ClassDeclaration>(nodeA, {}, fsModuleResolutionHost());
+
+			expect(isClassInstanceOf(resolvedNodeA.node, classA)).to.be.equal(true);
+		});
+
 	});
 
 });