Netlify Dev functions 500 error with package.json type="module"

[srobertson421]

Describe the bug

When running netlify dev with svelte@next (sveltekit), local lambda functions respond with 500 error. Would appear that netlify-cli/src/lib/functions/netlify-function.js is using lambda-local/build/lambdalocal.js to issue a CommonJS require of the function file but fails when "type"="module" exists in the root level package.json file as this tells Node to treat all .js files as ES modules.

To Reproduce

Steps to reproduce the behavior:

1. Run npm init svelte@next my-app && cd my-app && npm install
2. Install netlify-adapter for sveltekit: npm install --save-dev @sveltejs/adapter-netlify@next
3. Change svelte.config.js to utilize new adapter:

/** @type {import('@sveltejs/kit').Config} */
import adapter from '@sveltejs/adapter-netlify';
 
const config = {
  kit: {
    adapter: adapter(),
    // hydrate the <div id="svelte"> element in src/app.html
    target: '#svelte'
	}
};
 
export default config

4. Connect netlify-cli to local repo and netlify site to use netlify dev
5. Create netlify.toml in root and add these rules:

[build]
  command = "npm run build"
  publish = "build"

[functions]
  directory = "functions"
  node_bundler = "esbuild"

[dev]
  command = "npm run dev"
  targetPort = 3000
  port = 5000

[[redirects]]
  from = "/api/*"
  to = "/.netlify/functions/:splat"
  status = 200

[[redirects]]
  from = "/*"
  to = "/index.html"
  status = 200
  force = false

6. Run netlify functions:create test and select the "Hello World" option
7. Attempt to invoke the function from either the cli or from the svelte application.

Configuration

[build]
  command = "npm run build"
  publish = "build"

[functions]
  directory = "functions"
  node_bundler = "esbuild"

[dev]
  command = "npm run dev"
  targetPort = 3000
  port = 5000

[[redirects]]
  from = "/api/*"
  to = "/.netlify/functions/:splat"
  status = 200

[[redirects]]
  from = "/*"
  to = "/index.html"
  status = 200
  force = false

• Please enter the following command in a terminal and copy/paste its output:

System:
    OS: Linux 5.11 Ubuntu 21.04 (Hirsute Hippo)
    CPU: (4) x64 Intel(R) Core(TM) i5-7300U CPU @ 2.60GHz
    Memory: 616.22 MB / 7.65 GB
    Container: Yes
    Shell: 5.8 - /usr/bin/zsh
  Binaries:
    Node: 16.10.0 - ~/.nvm/versions/node/v16.10.0/bin/node
    npm: 7.24.0 - ~/.nvm/versions/node/v16.10.0/bin/npm
  npmGlobalPackages:
    netlify-cli: 6.9.15

Expected behavior

Expect the local functions structure to support "type"="module" in package.json

CLI Output

Request from ::1: GET /.netlify/functions/test
{"level":"error","message":"End - Error:"}
{"errorMessage":"require() of ES Module /home/sean/code/kit-test/functions/test/test.js from /home/sean/.nvm/versions/node/v16.10.0/lib/node_modules/netlify-cli/node_modules/lambda-local/build/lambdalocal.js not supported.\ntest.js is treated as an ES module file as it is a .js file whose nearest parent package.json contains \"type\": \"module\" which declares all .js files in that package scope as ES modules.\nInstead rename test.js to end in .cjs, change the requiring code to use dynamic import() which is available in all CommonJS modules, or change \"type\": \"module\" to \"type\": \"commonjs\" in /home/sean/code/kit-test/package.json to treat all .js files as CommonJS (using .mjs for all ES modules instead).\n","errorType":"Error","stackTrace":["t.js is treated as an ES module file as it is a .js file whose nearest parent package.json contains \"type\": \"module\" which declares all .js files in that package scope as ES modules.","tead rename test.js to end in .cjs, change the requiring code to use dynamic import() which is available in all CommonJS modules, or change \"type\": \"module\" to \"type\": \"commonjs\" in /home/sean/code/kit-test/package.json to treat all .js files as CommonJS (using .mjs for all ES modules instead).","","Object._executeSync (/home/sean/.nvm/versions/node/v16.10.0/lib/node_modules/netlify-cli/node_modules/lambda-local/build/lambdalocal.js:277:26)","/home/sean/.nvm/versions/node/v16.10.0/lib/node_modules/netlify-cli/node_modules/lambda-local/build/lambdalocal.js:95:26","new Promise (<anonymous>)","Object.execute (/home/sean/.nvm/versions/node/v16.10.0/lib/node_modules/netlify-cli/node_modules/lambda-local/build/lambdalocal.js:87:16)","Object.invokeFunction (/home/sean/.nvm/versions/node/v16.10.0/lib/node_modules/netlify-cli/src/lib/functions/runtimes/js/index.js:57:36)","NetlifyFunction.invoke (/home/sean/.nvm/versions/node/v16.10.0/lib/node_modules/netlify-cli/src/lib/functions/netlify-function.js:76:41)","async handler (/home/sean/.nvm/versions/node/v16.10.0/lib/node_modules/netlify-cli/src/lib/functions/server.js:103:33)"],"level":"error"}
Response with status 500 in 46 ms.

Additional context

Add any other context about the problem here.

[maddsua]

I don't think that it's resolved. Still getting a similar error, the only difference is that in my case CLI just dumps the entire error trace like this Error: require() of ES Module.... not supported...