Perf: bail out fast if input doesn't contain stylex

facebook · Dec 6, 2023 · b350894 · b350894
1 parent 0e3cfb4
commit b350894
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Showing 3 changed files with 20 additions and 2 deletions.
diff --git a/packages/nextjs-plugin/src/custom-webpack-loader.js b/packages/nextjs-plugin/src/custom-webpack-loader.js
@@ -9,8 +9,14 @@
 
 const PLUGIN_NAME = 'stylex';
 
-module.exports = function stylexLoader(inputCode) {
+module.exports = function stylexLoader(inputCode, inputSourceMap) {
   const callback = this.async();
+
+  // bail out early if the input doesn't contain "stylex"
+  if (!inputCode.includes('stylex')) {
+    return callback(null, inputCode, inputSourceMap);
+  }
+
   const { stylexPlugin } = this.getOptions();
   const logger = this._compiler.getInfrastructureLogger(PLUGIN_NAME);
 

diff --git a/packages/rollup-plugin/src/index.js b/packages/rollup-plugin/src/index.js
@@ -47,6 +47,12 @@ module.exports = function stylexPlugin({
       return false;
     },
     async transform(inputCode, id) {
+      // bail out early if the input doesn't contain "stylex"
+      if (!inputCode.includes('stylex')) {
+        // In rollup, returning null from any plugin phase means "no changes made".
+        return null;
+      }
+
       const { code, map, metadata } = await babel.transformAsync(inputCode, {
         babelrc: false,
         filename: id,

diff --git a/packages/webpack-plugin/src/loader.js b/packages/webpack-plugin/src/loader.js
@@ -11,8 +11,14 @@
 
 const PLUGIN_NAME = 'stylex';
 
-module.exports = function stylexLoader(inputCode) {
+module.exports = function stylexLoader(inputCode, inputSourceMap) {
   const callback = this.async();
+
+  // bail out early if the input doesn't contain "stylex"
+  if (!inputCode.includes('stylex')) {
+    return callback(null, inputCode, inputSourceMap);
+  }
+
   const { stylexPlugin } = this.getOptions();
   const logger = this._compiler.getInfrastructureLogger(PLUGIN_NAME);