feat: added the immutable flag to asset with hash in name (#525)

Author: evilebottnawi

src/index.js

@@ -110,15 +110,21 @@ class CopyPlugin {
                 return;
               }
 
-              const info = compilation.getAsset(targetPath);
+              const existingAsset = compilation.getAsset(targetPath);
 
-              if (info) {
+              if (existingAsset) {
                 if (force) {
                   logger.log(
                     `force updating '${webpackTo}' to compilation assets from '${absoluteFrom}'`
                   );
 
-                  compilation.updateAsset(targetPath, source, { copied: true });
+                  const info = { copied: true };
+
+                  if (asset.immutable) {
+                    info.immutable = true;
+                  }
+
+                  compilation.updateAsset(targetPath, source, info);
 
                   return;
                 }
@@ -134,7 +140,13 @@ class CopyPlugin {
                 `writing '${webpackTo}' to compilation assets from '${absoluteFrom}'`
               );
 
-              compilation.emitAsset(targetPath, source, { copied: true });
+              const info = { copied: true };
+
+              if (asset.immutable) {
+                info.immutable = true;
+              }
+
+              compilation.emitAsset(targetPath, source, info);
             });
 
           logger.debug('end to adding additional assets');

src/postProcessPattern.js

@@ -95,6 +95,10 @@ export default async function postProcessPattern(globalRef, pattern, file) {
       file.webpackTo = file.webpackTo.replace(/\.?\[ext]/g, '');
     }
 
+    file.immutable = /\[(?:([^:\]]+):)?(?:hash|contenthash)(?::([a-z]+\d*))?(?::(\d+))?\]/gi.test(
+      file.webpackTo
+    );
+
     file.webpackTo = loaderUtils.interpolateName(
       { resourcePath: file.absoluteFrom },
       file.webpackTo,
@@ -113,6 +117,7 @@ export default async function postProcessPattern(globalRef, pattern, file) {
       `transforming path '${file.webpackTo}' for '${file.absoluteFrom}'`
     );
 
+    file.immutable = false;
     file.webpackTo = await pattern.transformPath(
       file.webpackTo,
       file.absoluteFrom

test/CopyPlugin.test.js

@@ -304,6 +304,50 @@ describe('CopyPlugin', () => {
         .catch(done);
     });
 
+    it('should copy files with "copied" flags', (done) => {
+      expect.assertions(5);
+
+      const expectedAssetKeys = [
+        'directoryfile.5d7817ed5bc246756d73d6a4c8e94c33.txt',
+        '.dottedfile.5e294e270db6734a42f014f0dd18d9ac',
+        'nested/nestedfile.31d6cfe0d16ae931b73c59d7e0c089c0.txt',
+        'nested/deep-nested/deepnested.31d6cfe0d16ae931b73c59d7e0c089c0.txt',
+      ];
+
+      run({
+        preCopy: {
+          additionalAssets: [
+            {
+              name: 'directoryfile.5d7817ed5bc246756d73d6a4c8e94c33.txt',
+              data: 'Content',
+              info: { custom: true },
+            },
+          ],
+        },
+        expectedAssetKeys,
+        patterns: [
+          {
+            from: 'directory',
+            to: '[path][name].[contenthash].[ext]',
+            force: true,
+          },
+        ],
+      })
+        .then(({ stats }) => {
+          for (const name of expectedAssetKeys) {
+            const info = stats.compilation.assetsInfo.get(name);
+
+            expect(info.immutable).toBe(true);
+
+            if (name === 'directoryfile.5d7817ed5bc246756d73d6a4c8e94c33.txt') {
+              expect(info.immutable).toBe(true);
+            }
+          }
+        })
+        .then(done)
+        .catch(done);
+    });
+
     it('should copy files and print "copied" in the string representation ', (done) => {
       const isWebpack4 = webpack.version[0] === '4';