Merge pull request #2915 from devversion/config-bazel

refactor(config-loader): do not lookup `package.json` with explicit extensions

Author: bashmish

.changeset/nice-guests-invent.md

@@ -0,0 +1,9 @@
+---
+'@web/config-loader': patch
+---
+
+Optimizes config loading to not look for `package.json` in file system if the
+config extension is already informing whether CommonJS or ESM is used.
+
+Currently config loading did unnecessarily traverse the file system. This could
+be unnecessary slowness, or cause issues in sandbox environments (like Bazel)

packages/config-loader/src/importOrRequireConfig.js

@@ -17,7 +17,6 @@ function importConfig(configPath) {
  * @param {string} basedir
  */
 async function importOrRequireConfig(configPath, basedir) {
-  const packageType = await getPackageType(basedir);
   const ext = path.extname(configPath);
 
   switch (ext) {
@@ -26,6 +25,7 @@ async function importOrRequireConfig(configPath, basedir) {
     case '.cjs':
       return requireConfig(configPath);
     default:
+      const packageType = await getPackageType(basedir);
       return packageType === 'module' ? importConfig(configPath) : requireConfig(configPath);
   }
 }