add experimental.swcFileReading flag to disable file reading in swc (v…

…ercel#31995) automatically disable swc file reading when wasm builds are used and for virtual or yarn cache paths ## Bug - [ ] Related issues linked using `fixes #number` - [ ] Integration tests added - [ ] Errors have helpful link attached, see `contributing.md` ## Feature - [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR. - [ ] Related issues linked using `fixes #number` - [ ] Integration tests added - [ ] Documentation added - [ ] Telemetry added. In case of a feature if it's used or not. - [ ] Errors have helpful link attached, see `contributing.md` ## Documentation / Examples - [ ] Make sure the linting passes by running `yarn lint` Co-authored-by: Maia Teegarden <[email protected]>
ijjk · Dec 2, 2021 · 494e37c · 494e37c
1 parent 5747435
commit 494e37c
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Showing 4 changed files with 33 additions and 19 deletions.
diff --git a/packages/next/build/swc/index.js b/packages/next/build/swc/index.js
@@ -19,6 +19,7 @@ async function loadWasm() {
         bindings = await bindings.default()
       }
       return {
+        isWasm: true,
         transform(src, options) {
           return Promise.resolve(
             bindings.transformSync(src.toString(), options)
@@ -63,6 +64,7 @@ function loadNative() {
 
   if (bindings) {
     return {
+      isWasm: false,
       transform(src, options) {
         const isModule =
           typeof src !== undefined &&
@@ -133,6 +135,11 @@ function toBuffer(t) {
   return Buffer.from(JSON.stringify(t))
 }
 
+export async function isWasm() {
+  let bindings = await loadBindings()
+  return bindings.isWasm
+}
+
 export async function transform(src, options) {
   let bindings = await loadBindings()
   return bindings.transform(src, options)

diff --git a/packages/next/build/webpack-config.ts b/packages/next/build/webpack-config.ts
@@ -445,6 +445,7 @@ export default async function getBaseWebpackConfig(
             isServer: isMiddleware || isServer,
             pagesDir,
             hasReactRefresh: !isMiddleware && hasReactRefresh,
+            fileReading: config.experimental.swcFileReading,
             nextConfig: config,
             jsConfig,
           },

diff --git a/packages/next/build/webpack/loaders/next-swc-loader.js b/packages/next/build/webpack/loaders/next-swc-loader.js
@@ -26,7 +26,7 @@ IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 DEALINGS IN THE SOFTWARE.
 */
 
-import { transform } from '../../swc'
+import { isWasm, transform } from '../../swc'
 import { getLoaderSWCOptions } from '../../swc/options'
 import { isAbsolute } from 'path'
 
@@ -93,26 +93,30 @@ async function loaderTransform(parentTrace, source, inputSourceMap) {
   )
 }
 
+const EXCLUDED_PATHS =
+  /[\\/](cache[\\/][^\\/]+\.zip[\\/]node_modules|__virtual__)[\\/]/g
+
 export function pitch() {
-  if (
-    this.loaders.length - 1 === this.loaderIndex &&
-    isAbsolute(this.resourcePath)
-  ) {
-    const loaderSpan = this.currentTraceSpan.traceChild('next-swc-loader')
-    const callback = this.async()
-    loaderSpan
-      .traceAsyncFn(() => loaderTransform.call(this, loaderSpan))
-      .then(
-        ([transformedSource, outputSourceMap]) => {
-          this.addDependency(this.resourcePath)
-          callback(null, transformedSource, outputSourceMap)
-        },
-        (err) => {
-          this.addDependency(this.resourcePath)
-          callback(err)
-        }
+  const callback = this.async()
+  ;(async () => {
+    let loaderOptions = this.getOptions() || {}
+    if (
+      loaderOptions.fileReading &&
+      !EXCLUDED_PATHS.test(this.resourcePath) &&
+      this.loaders.length - 1 === this.loaderIndex &&
+      isAbsolute(this.resourcePath) &&
+      !(await isWasm())
+    ) {
+      const loaderSpan = this.currentTraceSpan.traceChild('next-swc-loader')
+      this.addDependency(this.resourcePath)
+      return loaderSpan.traceAsyncFn(() =>
+        loaderTransform.call(this, loaderSpan)
       )
-  }
+    }
+  })().then((r) => {
+    if (r) return callback(null, ...r)
+    callback()
+  }, callback)
 }
 
 export default function swcLoader(inputSource, inputSourceMap) {

diff --git a/packages/next/server/config-shared.ts b/packages/next/server/config-shared.ts
@@ -139,6 +139,7 @@ export type NextConfig = { [key: string]: any } & {
         }
     styledComponents?: boolean
     swcMinify?: boolean
+    swcFileReading?: boolean
     cpus?: number
     sharedPool?: boolean
     plugins?: boolean
@@ -243,6 +244,7 @@ export const defaultConfig: NextConfig = {
     reactRoot: Number(process.env.NEXT_PRIVATE_REACT_ROOT) > 0,
     disableOptimizedLoading: false,
     gzipSize: true,
+    swcFileReading: true,
     craCompat: false,
     esmExternals: true,
     // default to 50MB limit