feat: add readonly flag for filesystem cache

declarations/WebpackOptions.d.ts

@@ -1027,7 +1027,7 @@ export interface FileCacheOptions {
 	 */
 	profile?: boolean;
 	/**
-	 * Set filesystem cache in readonly mode. Main usage is for parallel webpack builds with warmed up cache.
+	 * Enable/disable readonly mode.
 	 */
 	readonly?: boolean;
 	/**

lib/cache/PackFileCacheStrategy.js

@@ -1216,6 +1216,8 @@ class PackFileCacheStrategy {
 	 * @returns {Promise<void>} promise
 	 */
 	store(identifier, etag, data) {
+		if (this.readonly) return Promise.resolve();
+
 		return this._getPack().then(pack => {
 			pack.set(identifier, etag === null ? null : etag.toString(), data);
 		});
@@ -1242,16 +1244,11 @@ class PackFileCacheStrategy {
 	}
 
 	storeBuildDependencies(dependencies) {
+		if (this.readonly) return;
 		this.newBuildDependencies.addAll(dependencies);
 	}
 
 	afterAllStored() {
-		if (this.readonly) {
-			this.logger.log(`Readonly mode. Skip storing cache.`);
-			this.packPromise = undefined;
-			return Promise.resolve();
-		}
-
 		const packPromise = this.packPromise;
 		if (packPromise === undefined) return Promise.resolve();
 		const reportProgress = ProgressPlugin.getReporter(this.compiler);

schemas/WebpackOptions.json

@@ -1255,7 +1255,7 @@
           "type": "boolean"
         },
         "readonly": {
-          "description": "Set filesystem cache in readonly mode. Main usage is for parallel webpack builds with warmed up cache.",
+          "description": "Enable/disable readonly mode.",
           "type": "boolean"
         },
         "store": {

test/PersistentCaching.test.js

@@ -210,6 +210,7 @@ sum([1,2,3])
 		});
 		await compile({ entry: `./src/main.js` });
 		const firstCacheFiles = (await readdir(cachePath)).sort();
+		// cSpell:words Mtimes
 		const firstMtimes = firstCacheFiles.map(
 			f => fs.statSync(path.join(cachePath, f)).mtime
 		);
@@ -230,6 +231,7 @@ import 'lodash';
 		expect(cacheFiles).toStrictEqual(firstCacheFiles);
 		expect(
 			firstCacheFiles.map(f => fs.statSync(path.join(cachePath, f)).mtime)
+			// cSpell:words Mtimes
 		).toStrictEqual(firstMtimes);
-	}, 120000);
+	}, 20000);
 });

test/__snapshots__/Cli.basictest.js.snap

@@ -323,13 +323,13 @@ Object {
   "cache-readonly": Object {
     "configs": Array [
       Object {
-        "description": "Set filesystem cache in readonly mode. Main usage is for parallel webpack builds with warmed up cache.",
+        "description": "Enable/disable readonly mode.",
         "multiple": false,
         "path": "cache.readonly",
         "type": "boolean",
       },
     ],
-    "description": "Set filesystem cache in readonly mode. Main usage is for parallel webpack builds with warmed up cache.",
+    "description": "Enable/disable readonly mode.",
     "multiple": false,
     "simpleType": "boolean",
   },

types.d.ts

@@ -4262,7 +4262,7 @@ declare interface FileCacheOptions {
 	profile?: boolean;
 
 	/**
-	 * Set filesystem cache in readonly mode. Main usage is for parallel webpack builds with warmed up cache.
+	 * Enable/disable readonly mode.
 	 */
 	readonly?: boolean;