feat: add `snapshot.contextModule `to configure snapshots for context modules

declarations/WebpackOptions.d.ts

@@ -2475,6 +2475,19 @@ export interface SnapshotOptions {
 		 */
 		timestamp?: boolean;
 	};
+	/**
+	 * Options for snapshotting the context module to determine if it needs to be built again.
+	 */
+	contextModule?: {
+		/**
+		 * Use hashes of the content of the files/directories to determine invalidation.
+		 */
+		hash?: boolean;
+		/**
+		 * Use timestamps of the files/directories to determine invalidation.
+		 */
+		timestamp?: boolean;
+	};
 	/**
 	 * List of paths that are managed by a package manager and contain a version or hash in its path so all files are immutable.
 	 */

lib/ContextModule.js

@@ -109,8 +109,6 @@ const makeSerializable = require("./util/makeSerializable");
 
 /** @typedef {Record<ModuleId, FakeMapType>} FakeMap */
 
-const SNAPSHOT_OPTIONS = { timestamp: true };
-
 class ContextModule extends Module {
 	/**
 	 * @param {ResolveDependencies} resolveDependencies function to get dependencies in this context
@@ -535,6 +533,8 @@ class ContextModule extends Module {
 			}
 			if (!this.context && !this.options.resource) return callback();
 
+			const snapshotOptions = compilation.options.snapshot.contextModule;
+
 			compilation.fileSystemInfo.createSnapshot(
 				startTime,
 				null,
@@ -544,7 +544,7 @@ class ContextModule extends Module {
 						? [this.options.resource]
 						: /** @type {string[]} */ (this.options.resource),
 				null,
-				SNAPSHOT_OPTIONS,
+				snapshotOptions,
 				(err, snapshot) => {
 					if (err) return callback(err);
 					/** @type {BuildInfo} */

lib/config/defaults.js

@@ -694,6 +694,7 @@ const applySnapshotDefaults = (snapshot, { production, futureDefaults }) => {
 	F(snapshot, "module", () =>
 		production ? { timestamp: true, hash: true } : { timestamp: true }
 	);
+	F(snapshot, "contextModule", () => ({ timestamp: true }));
 	F(snapshot, "resolve", () =>
 		production ? { timestamp: true, hash: true } : { timestamp: true }
 	);

lib/config/normalization.js

@@ -457,6 +457,13 @@ const getNormalizedWebpackOptions = (config) => ({
 			timestamp: module.timestamp,
 			hash: module.hash
 		})),
+		contextModule: optionalNestedConfig(
+			snapshot.contextModule,
+			(contextModule) => ({
+				timestamp: contextModule.timestamp,
+				hash: contextModule.hash
+			})
+		),
 		immutablePaths: optionalNestedArray(snapshot.immutablePaths, (p) => [...p]),
 		managedPaths: optionalNestedArray(snapshot.managedPaths, (p) => [...p]),
 		unmanagedPaths: optionalNestedArray(snapshot.unmanagedPaths, (p) => [...p])

schemas/WebpackOptions.json

@@ -5022,6 +5022,21 @@
             }
           }
         },
+        "contextModule": {
+          "description": "Options for snapshotting the context module to determine if it needs to be built again.",
+          "type": "object",
+          "additionalProperties": false,
+          "properties": {
+            "hash": {
+              "description": "Use hashes of the content of the files/directories to determine invalidation.",
+              "type": "boolean"
+            },
+            "timestamp": {
+              "description": "Use timestamps of the files/directories to determine invalidation.",
+              "type": "boolean"
+            }
+          }
+        },
         "immutablePaths": {
           "description": "List of paths that are managed by a package manager and contain a version or hash in its path so all files are immutable.",
           "type": "array",

test/Defaults.unittest.js

@@ -653,6 +653,9 @@ describe("snapshots", () => {
 		      "hash": true,
 		      "timestamp": true,
 		    },
+		    "contextModule": Object {
+		      "timestamp": true,
+		    },
 		    "immutablePaths": Array [],
 		    "managedPaths": Array [
 		      "<cwd>/node_modules/",

test/PersistentCaching.test.js

@@ -82,6 +82,16 @@ describe("Persistent Caching", () => {
 			);
 		});
 
+	const getCacheFileTimes = async () => {
+		const cacheFiles = (await readdir(cachePath)).sort();
+		return new Map(
+			cacheFiles.map((f) => [
+				f,
+				fs.statSync(path.join(cachePath, f)).mtime.toString()
+			])
+		);
+	};
+
 	const execute = () => {
 		const cache = {};
 		const require = (name) => {
@@ -230,11 +240,7 @@ 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
-		);
+		const firstCacheFileTimes = await getCacheFileTimes();
 
 		await updateSrc({
 			"main.js": `
@@ -248,11 +254,29 @@ import 'lodash';
 				readonly: true
 			}
 		});
-		const cacheFiles = (await readdir(cachePath)).sort();
-		expect(cacheFiles).toStrictEqual(firstCacheFiles);
-		expect(
-			firstCacheFiles.map((f) => fs.statSync(path.join(cachePath, f)).mtime)
-			// cSpell:words Mtimes
-		).toStrictEqual(firstMtimes);
+		await expect(getCacheFileTimes()).resolves.toEqual(firstCacheFileTimes);
+	}, 20000);
+
+	it("should not invalidate cache files if timestamps changed with dynamic import()", async () => {
+		const configAdditions = {
+			entry: "./src/main.js",
+			snapshot: {
+				resolve: { hash: true },
+				module: { hash: true },
+				contextModule: { hash: true }
+			}
+		};
+		await updateSrc({
+			"newer.js": "export default 2;",
+			// eslint-disable-next-line no-template-curly-in-string
+			"main.js": 'const f = "newer.js"; import(`./${f}`);'
+		});
+		await compile(configAdditions);
+		const firstCacheFileTimes = await getCacheFileTimes();
+
+		await utimes(path.resolve(srcPath, "newer.js"), new Date(), new Date());
+
+		await compile(configAdditions);
+		await expect(getCacheFileTimes()).resolves.toEqual(firstCacheFileTimes);
 	}, 20000);
 });

test/__snapshots__/Cli.basictest.js.snap

@@ -8830,6 +8830,32 @@ Object {
     "multiple": false,
     "simpleType": "boolean",
   },
+  "snapshot-context-module-hash": Object {
+    "configs": Array [
+      Object {
+        "description": "Use hashes of the content of the files/directories to determine invalidation.",
+        "multiple": false,
+        "path": "snapshot.contextModule.hash",
+        "type": "boolean",
+      },
+    ],
+    "description": "Use hashes of the content of the files/directories to determine invalidation.",
+    "multiple": false,
+    "simpleType": "boolean",
+  },
+  "snapshot-context-module-timestamp": Object {
+    "configs": Array [
+      Object {
+        "description": "Use timestamps of the files/directories to determine invalidation.",
+        "multiple": false,
+        "path": "snapshot.contextModule.timestamp",
+        "type": "boolean",
+      },
+    ],
+    "description": "Use timestamps of the files/directories to determine invalidation.",
+    "multiple": false,
+    "simpleType": "boolean",
+  },
   "snapshot-immutable-paths": Object {
     "configs": Array [
       Object {

types.d.ts

@@ -16170,6 +16170,20 @@ declare interface SnapshotOptionsWebpackOptions {
 		timestamp?: boolean;
 	};
 
+	/**
+	 * Options for snapshotting the context module to determine if it needs to be built again.
+	 */
+	contextModule?: {
+		/**
+		 * Use hashes of the content of the files/directories to determine invalidation.
+		 */
+		hash?: boolean;
+		/**
+		 * Use timestamps of the files/directories to determine invalidation.
+		 */
+		timestamp?: boolean;
+	};
+
 	/**
 	 * List of paths that are managed by a package manager and contain a version or hash in its path so all files are immutable.
 	 */