fix(aws-lambda-nodejs): Default entry finding when Node returns paths starting with file://

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

@@ -6,7 +6,7 @@ import { Construct } from 'constructs';
 import { Bundling } from './bundling';
 import { LockFile } from './package-manager';
 import { BundlingOptions } from './types';
-import { callsites, findUpMultiple } from './util';
+import { callsites, findDefiningFile, findUpMultiple } from './util';
 
 /**
  * Properties for a NodejsFunction
@@ -168,44 +168,23 @@ function findEntry(id: string, entry?: string): string {
     return entry;
   }
 
-  const definingFile = findDefiningFile();
+  const definingFile = findDefiningFile(callsites());
   const extname = path.extname(definingFile);
 
-  const tsHandlerFile = definingFile.replace(new RegExp(`${extname}$`), `.${id}.ts`);
+  const tsHandlerFile = definingFile.replace(new RegExp(`${extname}$`), `.${id}.ts`).replace('file://', '');
   if (fs.existsSync(tsHandlerFile)) {
     return tsHandlerFile;
   }
 
-  const jsHandlerFile = definingFile.replace(new RegExp(`${extname}$`), `.${id}.js`);
+  const jsHandlerFile = definingFile.replace(new RegExp(`${extname}$`), `.${id}.js`).replace('file://', '');
   if (fs.existsSync(jsHandlerFile)) {
     return jsHandlerFile;
   }
 
-  const mjsHandlerFile = definingFile.replace(new RegExp(`${extname}$`), `.${id}.mjs`);
+  const mjsHandlerFile = definingFile.replace(new RegExp(`${extname}$`), `.${id}.mjs`).replace('file://', '');
   if (fs.existsSync(mjsHandlerFile)) {
     return mjsHandlerFile;
   }
 
   throw new Error(`Cannot find handler file ${tsHandlerFile}, ${jsHandlerFile} or ${mjsHandlerFile}`);
 }
-
-/**
- * Finds the name of the file where the `NodejsFunction` is defined
- */
-function findDefiningFile(): string {
-  let definingIndex;
-  const sites = callsites();
-  for (const [index, site] of sites.entries()) {
-    if (site.getFunctionName() === 'NodejsFunction') {
-      // The next site is the site where the NodejsFunction was created
-      definingIndex = index + 1;
-      break;
-    }
-  }
-
-  if (!definingIndex || !sites[definingIndex]) {
-    throw new Error('Cannot find defining file.');
-  }
-
-  return sites[definingIndex].getFileName();
-}

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

@@ -208,3 +208,24 @@ function extractTsConfig(tsconfigPath: string, previousCompilerOptions?: Record<
   }
   return updatedCompilerOptions;
 }
+
+
+/**
+ * Finds the name of the file where the `NodejsFunction` is defined
+ */
+export function findDefiningFile(sites: CallSite[]): string {
+  let definingIndex;
+  for (const [index, site] of sites.entries()) {
+    if (site.getFunctionName() === 'NodejsFunction') {
+      // The next site is the site where the NodejsFunction was created
+      definingIndex = index + 1;
+      break;
+    }
+  }
+
+  if (!definingIndex || !sites[definingIndex]) {
+    throw new Error('Cannot find defining file.');
+  }
+
+  return sites[definingIndex].getFileName();
+}

packages/@aws-cdk/aws-lambda-nodejs/test/function_esmPaths.test.handler1.ts

@@ -0,0 +1 @@
+// Dummy for test purposes

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

@@ -0,0 +1,51 @@
+import { Template } from '@aws-cdk/assertions';
+import { CodeConfig } from '@aws-cdk/aws-lambda';
+import { Stack } from '@aws-cdk/core';
+import { NodejsFunction } from '../lib';
+import { Bundling } from '../lib/bundling';
+import { CallSite } from '../lib/util';
+import * as util from '../lib/util';
+
+jest.mock('../lib/bundling', () => {
+  return {
+    Bundling: {
+      bundle: jest.fn().mockReturnValue({
+        bind: (): CodeConfig => {
+          return {
+            s3Location: {
+              bucketName: 'my-bucket',
+              objectKey: 'my-key',
+            },
+          };
+        },
+        bindToResource: () => { return; },
+      }),
+    },
+  };
+});
+
+const actualFindDefiningFile = util.findDefiningFile;
+
+jest.spyOn(util, 'findDefiningFile').mockImplementation((sites: CallSite[]): string => {
+  return 'file://' + actualFindDefiningFile(sites);
+});
+
+let stack: Stack;
+beforeEach(() => {
+  stack = new Stack();
+  jest.clearAllMocks();
+});
+
+test('NodejsFunction with .ts handler, with ESM file:// paths', () => {
+  // WHEN
+  new NodejsFunction(stack, 'handler1');
+
+  expect(Bundling.bundle).toHaveBeenCalledWith(expect.objectContaining({
+    entry: expect.stringContaining('function_esmPaths.test.handler1.ts'), // Automatically finds .ts handler file
+  }));
+
+  Template.fromStack(stack).hasResourceProperties('AWS::Lambda::Function', {
+    Handler: 'index.handler',
+    Runtime: 'nodejs14.x',
+  });
+});