fix caching of asset modules

lib/Generator.js

@@ -28,6 +28,7 @@
  * @property {RuntimeSpec} runtime the runtime
  * @property {ConcatenationScope=} concatenationScope when in concatenated module, information about other concatenated modules
  * @property {string} type which kind of code should be generated
+ * @property {function(): Map<string, any>=} getData get access to the code generation data
  */
 
 /**

lib/NormalModule.js

@@ -993,6 +993,13 @@ class NormalModule extends Module {
 			runtimeRequirements.add(RuntimeGlobals.thisAsExports);
 		}
 
+		/** @type {Map<string, any>} */
+		let data;
+		const getData = () => {
+			if (data === undefined) data = new Map();
+			return data;
+		};
+
 		const sources = new Map();
 		for (const type of this.generator.getTypes(this)) {
 			const source = this.error
@@ -1007,6 +1014,7 @@ class NormalModule extends Module {
 						runtimeRequirements,
 						runtime,
 						concatenationScope,
+						getData,
 						type
 				  });
 
@@ -1018,7 +1026,8 @@ class NormalModule extends Module {
 		/** @type {CodeGenerationResult} */
 		const resultEntry = {
 			sources,
-			runtimeRequirements
+			runtimeRequirements,
+			data
 		};
 		return resultEntry;
 	}

lib/asset/AssetGenerator.js

@@ -47,7 +47,7 @@ class AssetGenerator extends Generator {
 	 */
 	generate(
 		module,
-		{ runtime, chunkGraph, runtimeTemplate, runtimeRequirements, type }
+		{ runtime, chunkGraph, runtimeTemplate, runtimeRequirements, type, getData }
 	) {
 		switch (type) {
 			case "asset":
@@ -146,6 +146,15 @@ class AssetGenerator extends Generator {
 						sourceFilename,
 						...info
 					};
+					if (getData) {
+						// Due to code generation caching module.buildInfo.XXX can't used to store such information
+						// It need to be stored in the code generation results instead, where it's cached too
+						// TODO webpack 6 For back-compat reasons we also store in on module.buildInfo
+						const data = getData();
+						data.set("fullContentHash", fullHash);
+						data.set("filename", filename);
+						data.set("assetInfo", info);
+					}
 
 					runtimeRequirements.add(RuntimeGlobals.publicPath); // add __webpack_require__.p
 

lib/asset/AssetModulesPlugin.js

@@ -145,14 +145,23 @@ class AssetModulesPlugin {
 					);
 					if (modules) {
 						for (const module of modules) {
+							const codeGenResult = codeGenerationResults.get(
+								module,
+								chunk.runtime
+							);
 							result.push({
-								render: () =>
-									codeGenerationResults.getSource(module, chunk.runtime, type),
-								filename: module.buildInfo.filename,
-								info: module.buildInfo.assetInfo,
+								render: () => codeGenResult.sources.get(type),
+								filename:
+									module.buildInfo.filename ||
+									codeGenResult.data.get("filename"),
+								info:
+									module.buildInfo.assetInfo ||
+									codeGenResult.data.get("assetInfo"),
 								auxiliary: true,
 								identifier: `assetModule${chunkGraph.getModuleId(module)}`,
-								hash: module.buildInfo.fullContentHash
+								hash:
+									module.buildInfo.fullContentHash ||
+									codeGenResult.data.get("fullContentHash")
 							});
 						}
 					}

lib/cache/IdleFileCachePlugin.js

@@ -127,9 +127,15 @@ class IdleFileCachePlugin {
 					});
 					return;
 				}
-				currentIdlePromise = currentIdlePromise.then(() =>
-					strategy.afterAllStored()
-				);
+				currentIdlePromise = currentIdlePromise
+					.then(() => strategy.afterAllStored())
+					.catch(err => {
+						const logger = compiler.getInfrastructureLogger(
+							"IdleFileCachePlugin"
+						);
+						logger.warn(`Background tasks during idle failed: ${err.message}`);
+						logger.debug(err.stack);
+					});
 				isInitialStore = false;
 			}
 		};

types.d.ts

@@ -3796,6 +3796,11 @@ declare interface GenerateContext {
 	 * which kind of code should be generated
 	 */
 	type: string;
+
+	/**
+	 * get access to the code generation data
+	 */
+	getData?: () => Map<string, any>;
 }
 declare class Generator {
 	constructor();