refactor: improve perf

Author: alexander-akait

README.md

@@ -294,8 +294,8 @@ module.exports = {
 
 #### `Array`
 
-If an array of functions is passed to the `minify` option, the `minimizerOptions` must also be an array.
 The function index in the `minify` array corresponds to the options object with the same index in the `minimizerOptions` array.
+If you use `minimizerOptions` like object, all `minify` function accept it.
 
 #### `processorOptions`
 

src/index.js

@@ -280,57 +280,34 @@ class CssMinimizerPlugin {
               input = input.toString();
             }
 
-            const minifyFns =
-              typeof this.options.minify === 'function'
-                ? [this.options.minify]
-                : this.options.minify;
-            const minimizerOptions = {
+            const options = {
               name,
               input,
               inputSourceMap,
+              minify: this.options.minify,
+              minifyOptions: this.options.minimizerOptions,
             };
 
-            let warnings = [];
-
-            this.options.minimizerOptions = Array.isArray(
-              this.options.minimizerOptions
-            )
-              ? this.options.minimizerOptions
-              : [this.options.minimizerOptions];
-
-            for await (const [i, minifyFunc] of minifyFns.entries()) {
-              minimizerOptions.minify = minifyFunc;
-              minimizerOptions.minimizerOptions = this.options.minimizerOptions[
-                i
-              ];
-
-              try {
-                output = await (getWorker
-                  ? getWorker().transform(serialize(minimizerOptions))
-                  : minifyFn(minimizerOptions));
-              } catch (error) {
-                compilation.errors.push(
-                  CssMinimizerPlugin.buildError(
-                    error,
-                    name,
-                    compilation.requestShortener,
-                    inputSourceMap &&
-                      CssMinimizerPlugin.isSourceMap(inputSourceMap)
-                      ? new SourceMapConsumer(inputSourceMap)
-                      : null
-                  )
-                );
-
-                return;
-              }
+            try {
+              output = await (getWorker
+                ? getWorker().transform(serialize(options))
+                : minifyFn(options));
+            } catch (error) {
+              compilation.errors.push(
+                CssMinimizerPlugin.buildError(
+                  error,
+                  name,
+                  compilation.requestShortener,
+                  inputSourceMap &&
+                    CssMinimizerPlugin.isSourceMap(inputSourceMap)
+                    ? new SourceMapConsumer(inputSourceMap)
+                    : null
+                )
+              );
 
-              minimizerOptions.input = output.code;
-              minimizerOptions.inputSourceMap = output.map;
-              warnings = warnings.concat(output.warnings);
+              return;
             }
 
-            output.warnings = warnings;
-
             if (output.map) {
               output.source = new SourceMapSource(
                 output.code,

src/minify.js

@@ -1,31 +1,35 @@
-/*
- * We bring to the line here, because when passing result from the worker,
- * the warning.toString is replaced with native Object.toString
- * */
-function warningsToString(warnings) {
-  return warnings.map((i) => i.toString());
-}
-
 const minify = async (options) => {
-  const {
-    name,
-    input,
-    minimizerOptions,
-    inputSourceMap,
-    minify: minifyFn,
-  } = options;
-
-  const result = await minifyFn(
-    { [name]: input },
-    inputSourceMap,
-    minimizerOptions
-  );
-
-  return {
-    code: result.code,
-    map: result.map,
-    warnings: warningsToString(result.warnings || []),
+  const minifyFns =
+    typeof options.minify === 'function' ? [options.minify] : options.minify;
+
+  const result = {
+    code: options.input,
+    map: options.inputSourceMap,
+    warnings: [],
   };
+
+  for (let i = 0; i <= minifyFns.length - 1; i++) {
+    const minifyFn = minifyFns[i];
+    const minifyOptions = Array.isArray(options.minifyOptions)
+      ? options.minifyOptions[i]
+      : options.minifyOptions;
+    // eslint-disable-next-line no-await-in-loop
+    const minifyResult = await minifyFn(
+      { [options.name]: result.code },
+      result.map,
+      minifyOptions
+    );
+
+    result.code = minifyResult.code;
+    result.map = minifyResult.map;
+    result.warnings = result.warnings.concat(minifyResult.warnings || []);
+  }
+
+  if (result.warnings.length > 0) {
+    result.warnings = result.warnings.map((warning) => warning.toString());
+  }
+
+  return result;
 };
 
 async function transform(options) {

test/__snapshots__/minify-option.test.js.snap

@@ -33,7 +33,8 @@ exports[`"minify" option should work if minify is array && minimizerOptions is a
 
 exports[`"minify" option should work if minify is array && minimizerOptions is object: assets 1`] = `
 Object {
-  "foo.css": "body {
+  "foo.css": "/*HERE*/.one{background: white;}
+body {
   font-weight: bold;
 }
 
@@ -45,7 +46,7 @@ body a {
 }
 
 .one{color: red;}
-.one{background: white;}
+/*HERE*/.one{background: white;}
 
 .two{color: red;}
 

test/minify-option.test.js

@@ -195,14 +195,14 @@ describe('"minify" option', () => {
         async (data, inputMap, minimizerOptions) => {
           const [input] = Object.values(data);
           return {
-            code: `${input}\n.one{color: red;}\n${minimizerOptions.test}\n`,
+            code: `${input}\n.one{color: red;}\n/*HERE*/${minimizerOptions.test}\n`,
             map: inputMap,
           };
         },
-        async (data, inputMap) => {
+        async (data, inputMap, minimizerOptions) => {
           const [input] = Object.values(data);
           return {
-            code: `${input}\n.two{color: red;}\n`,
+            code: `/*HERE*/${minimizerOptions.test}\n${input}\n.two{color: red;}\n`,
             map: inputMap,
           };
         },