fix(lambda-nodejs): local bundling fails with relative depsLockFilePa…

…th (aws#12125)

Ensure it's a file and make it absolute.

Closes aws#12115


----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/@aws-cdk/aws-lambda-nodejs/lib/function.ts

@@ -87,7 +87,10 @@ export class NodejsFunction extends lambda.Function {
  if (!fs.existsSync(props.depsLockFilePath)) {
  throw new Error(`Lock file at ${props.depsLockFilePath} doesn't exist`);
  }
- depsLockFilePath = props.depsLockFilePath;
+ if (!fs.statSync(props.depsLockFilePath).isFile()) {
+ throw new Error('`depsLockFilePath` should point to a file');
+ }
+ depsLockFilePath = path.resolve(props.depsLockFilePath);
  } else {
  const lockFile = findUp(LockFile.YARN) ?? findUp(LockFile.NPM);
  if (!lockFile) {

packages/@aws-cdk/aws-lambda-nodejs/test/function.test.ts

@@ -107,6 +107,22 @@ test('throws with non existing lock file', () => {
  })).toThrow(/Lock file at \/does\/not\/exist.lock doesn't exist/);
 });
 
+test('throws when depsLockFilePath is not a file', () => {
+ expect(() => new NodejsFunction(stack, 'handler1', {
+ depsLockFilePath: __dirname,
+ })).toThrow(/\`depsLockFilePath\` should point to a file/);
+});
+
+test('resolves depsLockFilePath to an absolute path', () => {
+ new NodejsFunction(stack, 'handler1', {
+ depsLockFilePath: './package.json',
+ });
+
+ expect(Bundling.bundle).toHaveBeenCalledWith(expect.objectContaining({
+ depsLockFilePath: expect.stringMatching(/@aws-cdk\/aws-lambda-nodejs\/package.json$/),
+ }));
+});
+
 test('resolves entry to an absolute path', () => {
  // WHEN
  new NodejsFunction(stack, 'fn', {