bug #649 Allow to use the [N] placeholder in copyFiles() (Lyrkan)

This PR was merged into the master branch.

Discussion
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Allow to use the [N] placeholder in copyFiles()

This PR should fix #647 by passing the `regExp` option to the `file-loader` used by `Encore.copyFiles()`.

It's a bit hacky since it changes the loader's options from the loader itself, but we should probably be fine for a while (I also tested it with `webpack@5.0.0-alpha.29` and the latest version of `file-loader@4.2.0`).

Commits
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b8ac398 Allow to use the [N] placeholder in copyFiles()

Author: weaverryan

lib/webpack/copy-files-loader.js

@@ -56,7 +56,7 @@ module.exports.default = function loader(source) {
     // The "source" part of the regexp is base64 encoded
     // in case it contains characters that don't work with
     // the "inline loader" syntax
-    const pattern = new RegExp(
+    const pattern = options.regExp || new RegExp(
         Buffer.from(options.patternSource, 'base64').toString(),
         options.patternFlags
     );
@@ -69,6 +69,23 @@ module.exports.default = function loader(source) {
         return 'module.exports = "";';
     }
 
+    // Add the "regExp" option (needed to use the [N] placeholder
+    // see: https://github.com/webpack-contrib/file-loader#n)
+    options.regExp = pattern;
+
+    // Remove copy-files-loader's custom options (in case the
+    // file-loader starts looking for thing it doesn't expect)
+    delete options.patternSource;
+    delete options.patternFlags;
+
+    // Update loader's options.
+    this.loaders.forEach(loader => {
+        if (__filename === loader.path) {
+            loader.options = options;
+            delete loader.query;
+        }
+    });
+
     // If everything is OK, let the file-loader do the copy
     return fileLoader.bind(this)(source);
 };

test/functional.js

@@ -2205,6 +2205,41 @@ module.exports = {
                     done();
                 });
             });
+
+            it('Can use the "[N]" placeholder', (done) => {
+                const config = createWebpackConfig('www/build', 'production');
+                config.addEntry('main', './js/no_require');
+                config.setPublicPath('/build');
+                config.copyFiles({
+                    from: './images',
+                    pattern: /(symfony)_(logo)\.png/,
+                    to: '[path][2]_[1].[ext]',
+                    includeSubdirectories: false
+                });
+
+                testSetup.runWebpack(config, (webpackAssert) => {
+                    expect(config.outputPath).to.be.a.directory()
+                        .with.files([
+                            'entrypoints.json',
+                            'runtime.js',
+                            'main.js',
+                            'manifest.json',
+                            'logo_symfony.png'
+                        ]);
+
+                    webpackAssert.assertManifestPath(
+                        'build/main.js',
+                        '/build/main.js'
+                    );
+
+                    webpackAssert.assertManifestPath(
+                        'build/symfony_logo.png',
+                        '/build/logo_symfony.png'
+                    );
+
+                    done();
+                });
+            });
         });
 
         describe('entrypoints.json & splitChunks()', () => {