fix: allow to use auto value with the publicPath option (#709)

src/loader.js

@@ -44,16 +44,22 @@ export function pitch(request) {
   const childFilename = '*';
   const publicPath =
     typeof options.publicPath === 'string'
-      ? options.publicPath === '' || options.publicPath.endsWith('/')
+      ? options.publicPath === 'auto'
+        ? ''
+        : options.publicPath === '' || options.publicPath.endsWith('/')
         ? options.publicPath
         : `${options.publicPath}/`
       : typeof options.publicPath === 'function'
       ? options.publicPath(this.resourcePath, this.rootContext)
+      : this._compilation.outputOptions.publicPath === 'auto'
+      ? ''
       : this._compilation.outputOptions.publicPath;
+
   const outputOptions = {
     filename: childFilename,
     publicPath,
   };
+
   const childCompiler = this._compilation.createChildCompiler(
     `${pluginName} ${request}`,
     outputOptions

test/cases/publicpath-compiler-auto/expected/main.css

@@ -0,0 +1,5 @@
+body {
+  background: red;
+  background-image: url(c9e192c015437a21dea1faa1d30f4941.svg);
+}
+

test/cases/publicpath-compiler-auto/index.js

@@ -0,0 +1 @@
+import './style.css';

test/cases/publicpath-compiler-auto/style.css

@@ -0,0 +1,4 @@
+body {
+  background: red;
+  background-image: url(./react.svg);
+}

test/cases/publicpath-compiler-auto/webpack.config.js

@@ -0,0 +1,38 @@
+import Self from '../../../src';
+
+module.exports = {
+  entry: './index.js',
+  output: {
+    publicPath: 'auto',
+  },
+  module: {
+    rules: [
+      {
+        test: /\.css$/,
+        use: [
+          {
+            loader: Self.loader,
+            options: {},
+          },
+          'css-loader',
+        ],
+      },
+      {
+        test: /\.(svg|png)$/,
+        use: [
+          {
+            loader: 'file-loader',
+            options: {
+              filename: '[name].[ext]',
+            },
+          },
+        ],
+      },
+    ],
+  },
+  plugins: [
+    new Self({
+      filename: '[name].css',
+    }),
+  ],
+};

test/cases/publicpath-loader-auto/expected/main.css

@@ -0,0 +1,5 @@
+body {
+  background: red;
+  background-image: url(c9e192c015437a21dea1faa1d30f4941.svg);
+}
+

test/cases/publicpath-loader-auto/index.js

@@ -0,0 +1 @@
+import './style.css';

test/cases/publicpath-loader-auto/style.css

@@ -0,0 +1,4 @@
+body {
+  background: red;
+  background-image: url(./react.svg);
+}

test/cases/publicpath-loader-auto/webpack.config.js

@@ -0,0 +1,37 @@
+import Self from '../../../src';
+
+module.exports = {
+  entry: './index.js',
+  module: {
+    rules: [
+      {
+        test: /\.css$/,
+        use: [
+          {
+            loader: Self.loader,
+            options: {
+              publicPath: 'auto',
+            },
+          },
+          'css-loader',
+        ],
+      },
+      {
+        test: /\.(svg|png)$/,
+        use: [
+          {
+            loader: 'file-loader',
+            options: {
+              filename: '[name].[ext]',
+            },
+          },
+        ],
+      },
+    ],
+  },
+  plugins: [
+    new Self({
+      filename: '[name].css',
+    }),
+  ],
+};