Issues with Snowpack v2.18.3+ (Yarn v2, React)

[mmillerbkg]

Hello everyone,

I am having some issues upgrading from Snowpack 2.18.2 to 2.18.4 (as well as 2.18.3). I've changed my snowpack.config.js to match create-snowpack-app's React template with no luck. So, for right now I have reverted back to 2.18.2 until I can figure out what the issue is. Below I've tried to list as much info as possible with the error.

Thank you and have a great day!

Env:
Node: v15.4.0
Yarn: 2.4.0

Snowpack Plugins:
"@snowpack/plugin-babel": "^2.1.5", "@snowpack/plugin-dotenv": "^2.0.5", "@snowpack/plugin-react-refresh": "^2.3.9", "@snowpack/plugin-webpack": "^2.2.0", "@snowpack/web-test-runner-plugin": "^0.1.5"

.babelrc:
{ "presets": ["@babel/preset-react"], "plugins": [["@emotion", { "sourceMap": false }], "graphql-tag"] }

Error message:
[snowpack] ! installing dependencies... [snowpack] The "path" argument must be of type string. Received an instance of Object [snowpack] TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received an instance of Object at new NodeError (node:internal/errors:278:15) at validateString (node:internal/validators:123:11) at Object.join (node:path:1081:7) at resolveWebDependency (/my-dir/node_modules/esinstall/lib/index.js:111:44) at Object.install (/my-dir/node_modules/esinstall/lib/index.js:267:36) at Object.run (/my-dir/node_modules/snowpack/lib/commands/install.js:91:43) at installDependencies (/my-dir/node_modules/snowpack/lib/sources/local.js:45:43) at async Object.prepare (/my-dir/node_modules/snowpack/lib/sources/local.js:97:35) at async startDevServer (/my-dir/node_modules/snowpack/lib/commands/dev.js:272:27) at async Object.command (/my-dir/node_modules/snowpack/lib/commands/dev.js:1218:9) at async cli (/my-dir/node_modules/snowpack/lib/index.js:155:9)

[FredKSchott]

I'm not sure why this would be. Do you see anything inside of resolveWebDependency that could be causing this? Possibly a bad package lookup? If you can add logs to /my-dir/node_modules/esinstall/lib/index.js:111:44 to debug, that would be great!

[mmillerbkg]

I'm sorry for the late reply. After a bit of hunting, it seems that esinstall does not support packages that have specific exports depending on the environment.

For example, nanoid (The package that was causing me issues) has a different entrypoints depending on environment. So, when esinstall looks for their export entrypoint, nanoid returns an object ex.{development: index.dev.js, production index.prod.js}instead of a string.

esinstall.ts
Line 144-147:

  const exportMapValue = resolveExportsMap(packageManifest, '.');
  if (exportMapValue) {
    const loc = path.join(packageManifestLoc, '..', exportMapValue);
    return {
      type: getWebDependencyType(loc),
      loc,
    };
  }

I implemented a fix on this file locally (simple check for an object and see if one of its properties match the current NODE_ENV, then load the value of the matching property) and everything works great!

Is there any way to handle this kind of behavior in snowpack.config.js?

[FredKSchott]

@matthewp just merged and released a fix for this, I believe. However, this isn't really supported by any tool as far as I can tell (not Node.js, at least iirc). If you have any official docs that describe what should happen with this export map entry, please share! Otherwise, we'll likely continue to ignore it