src/esbuild/index.ts (1)

102-133: 🚀 Performance & Scalability | 🟡 Minor | ⚡ Quick win

Cache check breaks for empty-content (stubbed) files.

The cache guard at Line 116 (if (fsContentsCache) return fsContentsCache) is falsy for an empty string, so once getContents() caches '' for an ENOENT/stubbed path (Line 131), every subsequent call within the same onTransformCb loop re-enters the try/catch and re-attempts fs.promises.readFile, re-triggering the ENOENT path each time instead of returning the cached value. This defeats the caching intent specifically for the scenario this PR targets.

🐛 Proposed fix using a defined-check instead of truthiness

-          let fsContentsCache: string | undefined
+          let fsContentsCache: string | undefined
+          let fsContentsCached = false

           for (const { options, onTransformCb } of loaders) {
             if (!checkFilter(options))
               continue

             if (onTransformCb) {
               const newArgs: OnTransformArgs = {
                 ...result,
                 ...args,
                 async getContents() {
                   if (result?.contents)
                     return result.contents as string

-                  if (fsContentsCache)
+                  if (fsContentsCached)
                     return fsContentsCache

                   // caution: 'utf8' assumes the input file is not in binary.
                   // if you want your plugin handle binary files, make sure to
                   // `plugin.load()` them first.
                   try {
-                    return (fsContentsCache = await fs.promises.readFile(args.path, 'utf8'))
+                    fsContentsCache = await fs.promises.readFile(args.path, 'utf8')
+                    fsContentsCached = true
+                    return fsContentsCache
                   }
                   catch (error) {
                     if ((error as NodeJS.ErrnoException)?.code === 'ENOENT')
-                      return (fsContentsCache = '')
+                      { fsContentsCache = ''; fsContentsCached = true; return fsContentsCache }
                     throw error
                   }
                 },
               }

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@src/esbuild/index.ts` around lines 102 - 133, The getContents cache in the
esbuild transform path treats an empty string as uncached, so stubbed or
ENOENT-backed files keep re-reading instead of reusing the cached empty result.
Update the cache guard inside the onTransformCb/getContents flow to check
whether fsContentsCache has been defined rather than relying on truthiness, so
the cached '' value is returned correctly on later calls.