resolve file path only when url is for a file path (Fixes #281)

Author: bjornstar

lib/loaders/get-format.mjs

@@ -5,14 +5,14 @@ import { send } from './ipc.mjs';
 const require = createRequire(import.meta.url);
 
 export async function getFormat(url, context, defaultGetFormat) {
-  const filePath = fileURLToPath(url);
+  const required = url.startsWith('file://') ? fileURLToPath(url) : url;
 
-  send({ required: filePath });
+  send({ required });
 
   try {
     return await defaultGetFormat(url, context, defaultGetFormat);
   } catch (error) {
     if (error.code !== 'ERR_UNKNOWN_FILE_EXTENSION') throw error;
-    return require('get-package-type')(filePath).then(format => ({ format }));
+    return require('get-package-type')(required).then(format => ({ format }));
   }
 }

lib/loaders/load.mjs

@@ -5,14 +5,14 @@ import { send } from './ipc.mjs';
 const require = createRequire(import.meta.url);
 
 export async function load(url, context, defaultLoad) {
-  const filePath = fileURLToPath(url);
+  const required = url.startsWith('file://') ? fileURLToPath(url) : url;
 
-  send({ required: filePath });
+  send({ required });
 
   try {
     return await defaultLoad(url, context, defaultLoad);
   } catch (error) {
     if (error.code !== 'ERR_UNKNOWN_FILE_EXTENSION') throw error;
-    return require('get-package-type')(filePath).then(format => ({ format, source: null }));
+    return require('get-package-type')(required).then(format => ({ format, source: null }));
   }
 }

lib/loaders/resolve.mjs

@@ -3,10 +3,10 @@ import { send } from './ipc.mjs';
 
 export function resolve(specifier, parentModule, defaultResolve) {
   const resolved = defaultResolve(specifier, parentModule);
+  const { url } = resolved;
+  const required = url.startsWith('file://') ? fileURLToPath(url) : url;
 
-  if (parentModule) {
-    send({ required: fileURLToPath(resolved.url) });
-  }
+  if (parentModule) send({ required });
 
   return resolved;
 }

test/fixture/builtin.mjs

@@ -0,0 +1,3 @@
+import { join } from 'path';
+
+console.log(join('hello', 'world'));

test/spawn/builtin.js

@@ -0,0 +1,9 @@
+const tap = require('tap');
+
+const { spawn } = require('../utils');
+
+tap.test('can import builtin modules', t => {
+  spawn('builtin.mjs', out => {
+    if (out.match(/^hello[/\\]world/)) return { exit: t.end.bind(t) };
+  });
+});