fix(Postgres Node): RMC do not mark collumn as required if identity_generation is BY DEFAULT (#13752)

Co-authored-by: Dana <152518854+dana-gill@users.noreply.github.com>

packages/nodes-base/nodes/Postgres/test/v2/resourceMapping.test.ts

@@ -0,0 +1,88 @@
+import type { MockProxy } from 'jest-mock-extended';
+import { mock } from 'jest-mock-extended';
+import type { ILoadOptionsFunctions } from 'n8n-workflow';
+
+import { getMappingColumns } from '../../v2/methods/resourceMapping';
+
+jest.mock('../../transport', () => {
+	const originalModule = jest.requireActual('../../transport');
+	return {
+		...originalModule,
+		configurePostgres: jest.fn(async () => ({ db: {} })),
+	};
+});
+
+jest.mock('../../v2/helpers/utils', () => {
+	const originalModule = jest.requireActual('../../v2/helpers/utils');
+	return {
+		...originalModule,
+		getEnums: jest.fn(() => []),
+		getEnumValues: jest.fn(),
+		getTableSchema: jest.fn(() => [
+			{
+				column_name: 'id',
+				data_type: 'bigint',
+				is_nullable: 'NO',
+				udt_name: 'int8',
+				column_default: null,
+				identity_generation: 'BY DEFAULT',
+				is_generated: 'NEVER',
+			},
+			{
+				column_name: 'name',
+				data_type: 'text',
+				is_nullable: 'YES',
+				udt_name: 'text',
+				column_default: null,
+				identity_generation: null,
+				is_generated: 'NEVER',
+			},
+		]),
+	};
+});
+
+describe('Postgres, resourceMapping', () => {
+	let loadOptionsFunctions: MockProxy<ILoadOptionsFunctions>;
+
+	beforeEach(() => {
+		loadOptionsFunctions = mock<ILoadOptionsFunctions>();
+	});
+
+	afterEach(() => {
+		jest.resetAllMocks();
+	});
+
+	it('should mark id as not required if identity_generation is "BY_DEFAULT"', async () => {
+		loadOptionsFunctions.getCredentials.mockResolvedValue({});
+		loadOptionsFunctions.getNodeParameter.mockReturnValueOnce('public');
+		loadOptionsFunctions.getNodeParameter.mockReturnValueOnce('test_table');
+		loadOptionsFunctions.getNodeParameter.mockReturnValueOnce('insert');
+
+		const fields = await getMappingColumns.call(loadOptionsFunctions);
+
+		expect(fields).toEqual({
+			fields: [
+				{
+					canBeUsedToMatch: true,
+					defaultMatch: true,
+					display: true,
+					displayName: 'id',
+					id: 'id',
+					options: undefined,
+					required: false,
+					type: 'number',
+				},
+				{
+					canBeUsedToMatch: true,
+					defaultMatch: false,
+					display: true,
+					displayName: 'name',
+					id: 'name',
+					options: undefined,
+					required: false,
+					type: 'string',
+				},
+			],
+		});
+	});
+});