fix: require ts optimistically (#388)

src/umzug.ts

@@ -168,10 +168,10 @@ export class Umzug<Ctx> extends EventEmitter {
 		}
 
 		const ext = path.extname(filepath);
-		const canRequire = ext === '.js' || ext in require.extensions;
+		const canRequire = ext === '.js' || ext === '.ts';
 		const languageSpecificHelp: Record<string, string> = {
 			'.ts':
-				"You can use the default resolver with typescript files by adding `ts-node` as a dependency and calling `require('ts-node/register')` at the program entrypoint before running migrations.",
+				"TypeScript files can be required by adding `ts-node` as a dependency and calling `require('ts-node/register')` at the program entrypoint before running migrations.",
 			'.sql': 'Try writing a resolver which reads file content and executes it as a sql query.',
 		};
 		if (!canRequire) {
@@ -183,7 +183,17 @@ export class Umzug<Ctx> extends EventEmitter {
 			throw new Error(errorParts.filter(Boolean).join(' '));
 		}
 
-		const getModule = () => require(filepath);
+		const getModule = () => {
+			try {
+				return require(filepath);
+			} catch (e: unknown) {
+				if (e instanceof Error && filepath.endsWith('.ts')) {
+					e.message += '\n\n' + languageSpecificHelp['.ts'];
+				}
+
+				throw e;
+			}
+		};
 
 		return {
 			name,

test/umzug.test.ts

@@ -317,6 +317,33 @@ describe('alternate migration inputs', () => {
 		expect(spy).toHaveBeenNthCalledWith(1, 'migration1-up');
 	});
 
+	test('typescript migration files', async () => {
+		const syncer = fsSyncer(path.join(__dirname, 'generated/umzug/typescript'), {
+			'm1.ts': `export const up = () => {}; export const down = () => {}`,
+			'm2.ts': `throw Error('Error to simulate typescript modules not being registered')`,
+		});
+		syncer.sync();
+
+		const umzug = new Umzug({
+			migrations: {
+				glob: ['*.ts', { cwd: syncer.baseDir }],
+			},
+			logger: undefined,
+		});
+
+		expect([names(await umzug.pending()), names(await umzug.executed())]).toEqual([['m1.ts', 'm2.ts'], []]);
+
+		await umzug.up({ to: 'm1.ts' });
+
+		expect([names(await umzug.pending()), names(await umzug.executed())]).toEqual([['m2.ts'], ['m1.ts']]);
+
+		await expect(umzug.up()).rejects.toThrowErrorMatchingInlineSnapshot(`
+			"Error to simulate typescript modules not being registered
+
+			TypeScript files can be required by adding \`ts-node\` as a dependency and calling \`require('ts-node/register')\` at the program entrypoint before running migrations."
+		`);
+	});
+
 	test('with custom file globbing options', async () => {
 		const spy = jest.fn();