refactor!: remove workarounds for the webpack v4 support

packages/configtest/src/index.ts

@@ -39,14 +39,7 @@ class ConfigTestCommand {
         cli.logger.info(`Validate '${Array.from(configPaths).join(" ,")}'.`);
 
         try {
-          // @ts-expect-error cli.webpack.validate returns void
-          const error: Error[] | undefined = cli.webpack.validate(config.options);
-
-          // TODO remove this after drop webpack@4
-          if (error && error.length > 0) {
-            // @ts-expect-error schema argument is missing
-            throw new cli.webpack.WebpackOptionsValidationError(error);
-          }
+          cli.webpack.validate(config.options);
         } catch (error) {
           if (cli.isValidationError(error as Error)) {
             cli.logger.error((error as Error).message);

packages/webpack-cli/src/types.ts

@@ -228,15 +228,6 @@ interface BasicPackageJsonContent {
   license: string;
 }
 
-/**
- * Webpack V4
- */
-
-type WebpackV4LegacyStats = Required<WebpackCLIStats>;
-interface WebpackV4Compiler extends Compiler {
-  compiler: Compiler;
-}
-
 /**
  * Plugins and util types
  */
@@ -320,10 +311,8 @@ export {
   WebpackCLICommandOptions,
   WebpackCLIMainOption,
   WebpackCLILogger,
-  WebpackV4LegacyStats,
   WebpackDevServerOptions,
   WebpackRunOptions,
-  WebpackV4Compiler,
   WebpackCompiler,
   WebpackConfiguration,
   Argv,

packages/webpack-cli/src/webpack-cli.ts

@@ -13,10 +13,8 @@ import {
   WebpackCLICommandOptions,
   WebpackCLIMainOption,
   WebpackCLILogger,
-  WebpackV4LegacyStats,
   WebpackDevServerOptions,
   WebpackRunOptions,
-  WebpackV4Compiler,
   WebpackCompiler,
   WebpackConfiguration,
   Argv,
@@ -34,7 +32,6 @@ import {
   Instantiable,
   JsonExt,
   ModuleName,
-  MultipleCompilerStatsOptions,
   PackageInstallOptions,
   PackageManager,
   Path,
@@ -2226,40 +2223,12 @@ class WebpackCLI implements IWebpackCLI {
       }
 
       // Setup stats
-      // TODO remove after drop webpack@4
-      const statsForWebpack4 =
-        this.webpack.Stats &&
-        (this.webpack.Stats as unknown as Partial<WebpackV4LegacyStats>).presetToOptions;
-
-      if (statsForWebpack4) {
-        if (typeof item.stats === "undefined") {
-          item.stats = {};
-        } else if (typeof item.stats === "boolean") {
-          item.stats = (this.webpack.Stats as unknown as WebpackV4LegacyStats).presetToOptions(
-            item.stats,
-          );
-        } else if (
-          typeof item.stats === "string" &&
-          (item.stats === "none" ||
-            item.stats === "verbose" ||
-            item.stats === "detailed" ||
-            item.stats === "normal" ||
-            item.stats === "minimal" ||
-            item.stats === "errors-only" ||
-            item.stats === "errors-warnings")
-        ) {
-          item.stats = (this.webpack.Stats as unknown as WebpackV4LegacyStats).presetToOptions(
-            item.stats,
-          );
-        }
-      } else {
-        if (typeof item.stats === "undefined") {
-          item.stats = { preset: "normal" };
-        } else if (typeof item.stats === "boolean") {
-          item.stats = item.stats ? { preset: "normal" } : { preset: "none" };
-        } else if (typeof item.stats === "string") {
-          item.stats = { preset: item.stats };
-        }
+      if (typeof item.stats === "undefined") {
+        item.stats = { preset: "normal" };
+      } else if (typeof item.stats === "boolean") {
+        item.stats = item.stats ? { preset: "normal" } : { preset: "none" };
+      } else if (typeof item.stats === "string") {
+        item.stats = { preset: item.stats };
       }
 
       let colors;
@@ -2277,10 +2246,7 @@ class WebpackCLI implements IWebpackCLI {
         colors = Boolean(this.colors.isColorSupported);
       }
 
-      // TODO remove after drop webpack v4
-      if (typeof item.stats === "object" && item.stats !== null) {
-        item.stats.colors = colors;
-      }
+      item.stats.colors = colors;
 
       // Apply CLI plugin
       if (!item.plugins) {
@@ -2305,12 +2271,7 @@ class WebpackCLI implements IWebpackCLI {
   }
 
   isValidationError(error: Error): error is WebpackError {
-    // https://github.com/webpack/webpack/blob/master/lib/index.js#L267
-    // https://github.com/webpack/webpack/blob/v4.44.2/lib/webpack.js#L90
-    const ValidationError =
-      this.webpack.ValidationError || this.webpack.WebpackOptionsValidationError;
-
-    return error instanceof ValidationError || error.name === "ValidationError";
+    return error instanceof this.webpack.ValidationError || error.name === "ValidationError";
   }
 
   async createCompiler(
@@ -2350,11 +2311,6 @@ class WebpackCLI implements IWebpackCLI {
       process.exit(2);
     }
 
-    // TODO webpack@4 return Watching and MultiWatching instead Compiler and MultiCompiler, remove this after drop webpack@4
-    if (compiler && (compiler as WebpackV4Compiler).compiler) {
-      compiler = (compiler as WebpackV4Compiler).compiler;
-    }
-
     return compiler;
   }
 
@@ -2406,17 +2362,6 @@ class WebpackCLI implements IWebpackCLI {
         ? compiler.options.stats
         : undefined;
 
-      // TODO webpack@4 doesn't support `{ children: [{ colors: true }, { colors: true }] }` for stats
-      const statsForWebpack4 =
-        this.webpack.Stats &&
-        (this.webpack.Stats as unknown as Partial<WebpackV4LegacyStats>).presetToOptions;
-
-      if (this.isMultipleCompiler(compiler) && statsForWebpack4) {
-        (statsOptions as StatsOptions).colors = (
-          statsOptions as MultipleCompilerStatsOptions
-        ).children.some((child) => child.colors);
-      }
-
       if (options.json && createJsonStringifyStream) {
         const handleWriteError = (error: WebpackError) => {
           this.logger.error(error);