fix(core): Ensure the generic OAuth2 API credential uses the OAuth2 credential test (#8941)

packages/cli/src/services/credentials-tester.service.ts

@@ -84,7 +84,7 @@ export class CredentialsTester {
 		return 'access_token' in oauthTokenData;
 	}
 
-	private getCredentialTestFunction(
+	getCredentialTestFunction(
 		credentialType: string,
 	): ICredentialTestFunction | ICredentialTestRequestData | undefined {
 		// Check if test is defined on credentials
@@ -116,7 +116,8 @@ export class CredentialsTester {
 				for (const { name, testedBy } of nodeType.description.credentials ?? []) {
 					if (
 						name === credentialType &&
-						this.credentialTypes.getParentTypes(name).includes('oAuth2Api')
+						(this.credentialTypes.getParentTypes(name).includes('oAuth2Api') ||
+							name === 'oAuth2Api')
 					) {
 						return async function oauth2CredTest(
 							this: ICredentialTestFunctions,

packages/cli/test/unit/credentials-tester.unit.test.ts

@@ -0,0 +1,32 @@
+import { CredentialsTester } from '@/services/credentials-tester.service';
+import mock from 'jest-mock-extended/lib/Mock';
+import type { CredentialTypes } from '@/CredentialTypes';
+import type { ICredentialType, INodeType } from 'n8n-workflow';
+import type { NodeTypes } from '@/NodeTypes';
+
+describe('CredentialsTester', () => {
+	const credentialTypes = mock<CredentialTypes>();
+	const nodeTypes = mock<NodeTypes>();
+	const credentialsTester = new CredentialsTester(mock(), credentialTypes, nodeTypes, mock());
+
+	beforeEach(() => {
+		jest.clearAllMocks();
+	});
+
+	it('should find the OAuth2 credential test for a generic OAuth2 API credential', () => {
+		credentialTypes.getByName.mockReturnValue(mock<ICredentialType>({ test: undefined }));
+		credentialTypes.getSupportedNodes.mockReturnValue(['oAuth2Api']);
+		credentialTypes.getParentTypes.mockReturnValue([]);
+		nodeTypes.getByName.mockReturnValue(
+			mock<INodeType>({
+				description: { credentials: [{ name: 'oAuth2Api' }] },
+			}),
+		);
+
+		const testFn = credentialsTester.getCredentialTestFunction('oAuth2Api');
+
+		if (typeof testFn !== 'function') fail();
+
+		expect(testFn.name).toBe('oauth2CredTest');
+	});
+});