chore: comments

lib/dependencies/URLDependency.js

@@ -155,13 +155,13 @@ URLDependency.Template = class URLDependencyTemplate extends (
 
 		runtimeRequirements.add(RuntimeGlobals.require);
 
-		// Check if we need to add prefetch/preload runtime
+		// Determine if prefetch/preload hints are specified
 		const needsPrefetch = dep.prefetch !== undefined && dep.prefetch !== false;
 		const needsPreload = dep.preload !== undefined && dep.preload !== false;
 
-		// Skip inline prefetch/preload if handled by startup module
+		// Generate inline prefetch/preload code if not handled by startup module
 		if ((needsPrefetch || needsPreload) && !dep._startupPrefetch) {
-			// Get the module to determine asset type
+			// Resolve module to determine appropriate asset type
 			const module = moduleGraph.getModule(dep);
 			let asType = "";
 
@@ -172,7 +172,7 @@ URLDependency.Template = class URLDependencyTemplate extends (
 				asType = getAssetType(request);
 			}
 
-			// Generate the module expression (just the module id)
+			// Get the module ID for runtime code generation
 			const moduleExpr = runtimeTemplate.moduleRaw({
 				chunkGraph,
 				module: moduleGraph.getModule(dep),
@@ -181,9 +181,9 @@ URLDependency.Template = class URLDependencyTemplate extends (
 				weak: false
 			});
 
-			// Build the prefetch/preload code
+			// Construct prefetch/preload function calls
 			const hintCode = [];
-			// Only pass valid fetchPriority values
+			// Validate fetchPriority against allowed values
 			const validFetchPriority =
 				dep.fetchPriority && ["high", "low", "auto"].includes(dep.fetchPriority)
 					? dep.fetchPriority
@@ -196,20 +196,20 @@ URLDependency.Template = class URLDependencyTemplate extends (
 				: "undefined";
 
 			if (needsPrefetch && !needsPreload) {
-				// Only prefetch
+				// Generate prefetch call
 				runtimeRequirements.add(RuntimeGlobals.prefetchAsset);
 				hintCode.push(
 					`${RuntimeGlobals.prefetchAsset}(url, "${asType}", ${fetchPriority}, ${preloadType});`
 				);
 			} else if (needsPreload) {
-				// Preload (takes precedence over prefetch)
+				// Generate preload call (overrides prefetch if both specified)
 				runtimeRequirements.add(RuntimeGlobals.preloadAsset);
 				hintCode.push(
 					`${RuntimeGlobals.preloadAsset}(url, "${asType}", ${fetchPriority}, ${preloadType});`
 				);
 			}
 
-			// Wrap in IIFE to execute hint code and return URL
+			// Create IIFE that generates URL and adds resource hints
 			if (dep.relative) {
 				runtimeRequirements.add(RuntimeGlobals.relativeUrl);
 				source.replace(
@@ -234,7 +234,7 @@ URLDependency.Template = class URLDependencyTemplate extends (
 				);
 			}
 		} else if ((needsPrefetch || needsPreload) && dep._startupPrefetch) {
-			// Prefetch/preload handled by startup module - generate standard URL
+			// Generate standard URL when prefetch/preload is handled by startup module
 			if (dep.relative) {
 				runtimeRequirements.add(RuntimeGlobals.relativeUrl);
 				source.replace(
@@ -264,14 +264,14 @@ URLDependency.Template = class URLDependencyTemplate extends (
 					})}, ${RuntimeGlobals.baseURI}`
 				);
 			}
-			// Still need to add runtime requirements for prefetch/preload
+			// Register runtime requirements for prefetch/preload functions
 			if (needsPrefetch && !needsPreload) {
 				runtimeRequirements.add(RuntimeGlobals.prefetchAsset);
 			} else if (needsPreload) {
 				runtimeRequirements.add(RuntimeGlobals.preloadAsset);
 			}
 		} else if (dep.relative) {
-			// No prefetch/preload - use original code
+			// Standard URL generation without resource hints
 			runtimeRequirements.add(RuntimeGlobals.relativeUrl);
 			source.replace(
 				dep.outerRange[0],

lib/prefetch/AssetPrefetchStartupPlugin.js

@@ -41,12 +41,12 @@ class AssetPrefetchStartupPlugin {
 			const assetPrefetchMap = new WeakMap();
 			const chunkAssetInfoMap = new WeakMap();
 
-			// Hook into finishModules to collect all URLDependencies
+			// Collect URLDependencies with prefetch/preload hints during module finalization
 			compilation.hooks.finishModules.tap(PLUGIN_NAME, (modules) => {
 				for (const module of modules) {
 					if (!module.dependencies) continue;
 
-					// Collect URLDependencies with prefetch/preload
+					// Find all URL dependencies that have prefetch or preload hints
 					const assetDeps = [];
 					for (const dep of module.dependencies) {
 						if (dep.constructor.name === "URLDependency") {
@@ -64,7 +64,7 @@ class AssetPrefetchStartupPlugin {
 				}
 			});
 
-			// Process assets when chunks are being optimized
+			// Aggregate prefetch/preload assets by chunk during optimization
 			compilation.hooks.optimizeChunks.tap(
 				{ name: PLUGIN_NAME, stage: 1 },
 				(chunks) => {
@@ -77,13 +77,13 @@ class AssetPrefetchStartupPlugin {
 							preload: /** @type {AssetInfo[]} */ ([])
 						};
 
-						// Process all modules in this chunk
+						// Iterate through all modules in the chunk
 						for (const module of chunkGraph.getChunkModules(chunk)) {
 							const urlDeps = assetPrefetchMap.get(module);
 							if (!urlDeps) continue;
 
 							for (const dep of urlDeps) {
-								// Mark dependency as handled by startup prefetch
+								// Flag this dependency as handled by startup module to prevent inline generation
 								dep._startupPrefetch = true;
 
 								const resolvedModule = moduleGraph.getModule(dep);
@@ -94,7 +94,7 @@ class AssetPrefetchStartupPlugin {
 								).request;
 								if (!request) continue;
 
-								// Get the actual asset filename from module buildInfo
+								// Extract the asset filename from module metadata
 								let assetUrl;
 								if (
 									resolvedModule.buildInfo &&
@@ -102,7 +102,7 @@ class AssetPrefetchStartupPlugin {
 								) {
 									assetUrl = resolvedModule.buildInfo.filename;
 								} else {
-									// Fallback to extracting from request
+									// Fall back to filename from request path
 									assetUrl = request.split(/[\\/]/).pop() || request;
 								}
 
@@ -160,18 +160,15 @@ class AssetPrefetchStartupPlugin {
 				}
 			);
 
-			// Ensure runtime functions are available
 			compilation.hooks.runtimeRequirementInTree
 				.for(RuntimeGlobals.prefetchAsset)
 				.tap(PLUGIN_NAME, (chunk, set) => {
-					// AssetPrefetchPreloadRuntimeModule will be added by URLParserPlugin
 					set.add(RuntimeGlobals.publicPath);
 				});
 
 			compilation.hooks.runtimeRequirementInTree
 				.for(RuntimeGlobals.preloadAsset)
 				.tap(PLUGIN_NAME, (chunk, set) => {
-					// AssetPrefetchPreloadRuntimeModule will be added by URLParserPlugin
 					set.add(RuntimeGlobals.publicPath);
 				});
 		});

lib/prefetch/AssetPrefetchStartupRuntimeModule.js

@@ -55,8 +55,8 @@ class AssetPrefetchStartupRuntimeModule extends RuntimeModule {
 		const lines = [];
 
 		/**
-		 * @param {AssetInfo} asset The asset information to serialize
-		 * @returns {string} Serialized arguments for prefetch/preload function
+		 * @param {AssetInfo} asset asset info object
+		 * @returns {string} serialized function arguments
 		 */
 		const serializeAsset = (asset) => {
 			const args = [

lib/runtime/AssetPrefetchPreloadPlugin.js

@@ -19,7 +19,7 @@ class AssetPrefetchPreloadPlugin {
 	 */
 	apply(compiler) {
 		compiler.hooks.compilation.tap(PLUGIN_NAME, (compilation) => {
-			// Add runtime module for asset prefetch
+			// Register runtime module for asset prefetch
 			compilation.hooks.runtimeRequirementInTree
 				.for(RuntimeGlobals.prefetchAsset)
 				.tap(PLUGIN_NAME, (chunk, set) => {
@@ -29,7 +29,7 @@ class AssetPrefetchPreloadPlugin {
 					);
 				});
 
-			// Add runtime module for asset preload
+			// Register runtime module for asset preload
 			compilation.hooks.runtimeRequirementInTree
 				.for(RuntimeGlobals.preloadAsset)
 				.tap(PLUGIN_NAME, (chunk, set) => {

lib/runtime/AssetPrefetchPreloadRuntimeModule.js

@@ -47,7 +47,7 @@ class AssetPrefetchPreloadRuntimeModule extends RuntimeModule {
 					"link.setAttribute('fetchpriority', fetchPriority);"
 				]),
 				"}",
-				// Add nonce if needed
+				// Apply nonce attribute for CSP if configured
 				compilation.outputOptions.crossOriginLoading
 					? Template.asString([
 							`if(${RuntimeGlobals.scriptNonce}) {`,

lib/url/URLParserPlugin.js

@@ -185,9 +185,9 @@ class URLParserPlugin {
 				);
 				dep.loc = /** @type {DependencyLocation} */ (expr.loc);
 
-				// Handle prefetch/preload hints
+				// Process magic comments for prefetch/preload hints
 				if (importOptions) {
-					// Validate webpackPrefetch
+					// webpackPrefetch should be boolean true
 					if (
 						importOptions.webpackPrefetch !== undefined &&
 						importOptions.webpackPrefetch !== true
@@ -200,7 +200,7 @@ class URLParserPlugin {
 						);
 					}
 
-					// Validate webpackPreload
+					// webpackPreload should be boolean true
 					if (
 						importOptions.webpackPreload !== undefined &&
 						importOptions.webpackPreload !== true
@@ -213,7 +213,7 @@ class URLParserPlugin {
 						);
 					}
 
-					// Validate webpackFetchPriority
+					// webpackFetchPriority should be one of: high, low, auto
 					if (
 						importOptions.webpackFetchPriority !== undefined &&
 						(typeof importOptions.webpackFetchPriority !== "string" ||
@@ -229,7 +229,7 @@ class URLParserPlugin {
 						);
 					}
 
-					// Validate webpackPreloadAs
+					// webpackPreloadAs should be a string
 					if (
 						importOptions.webpackPreloadAs !== undefined &&
 						typeof importOptions.webpackPreloadAs !== "string"
@@ -242,7 +242,7 @@ class URLParserPlugin {
 						);
 					}
 
-					// Validate webpackPreloadType
+					// webpackPreloadType should be a string
 					if (
 						importOptions.webpackPreloadType !== undefined &&
 						typeof importOptions.webpackPreloadType !== "string"
@@ -255,7 +255,7 @@ class URLParserPlugin {
 						);
 					}
 
-					// Store hints on the dependency for later use
+					// Store magic comment values on dependency
 					dep.prefetch = importOptions.webpackPrefetch;
 					dep.preload = importOptions.webpackPreload;
 					dep.fetchPriority = importOptions.webpackFetchPriority;
@@ -263,7 +263,7 @@ class URLParserPlugin {
 					dep.preloadType = importOptions.webpackPreloadType;
 				}
 
-				// Add dependency directly
+				// Register the dependency
 				parser.state.current.addDependency(dep);
 				InnerGraph.onUsage(parser.state, (e) => (dep.usedByExports = e));
 				return true;

lib/util/assetType.js

@@ -7,10 +7,9 @@
 
 /**
  * Determines the 'as' attribute value for prefetch/preload based on file extension
- * Reference: MDN rel=preload documentation
  * https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes/rel/preload#what_types_of_content_can_be_preloaded
- * @param {string} request The module request string or filename
- * @returns {string} The 'as' attribute value for link element
+ * @param {string} request module request string or filename
+ * @returns {string} asset type for link element 'as' attribute
  */
 const getAssetType = (request) => {
 	if (/\.(png|jpe?g|gif|svg|webp|avif|bmp|ico|tiff?)$/i.test(request)) {
@@ -26,8 +25,7 @@ const getAssetType = (request) => {
 	} else if (
 		/\.(mp4|webm|ogg|mp3|wav|flac|aac|m4a|avi|mov|wmv|mkv)$/i.test(request)
 	) {
-		// Audio/video files: use 'fetch' as fallback since as='audio'/'video' not supported
-		// Reference: https://github.com/mdn/browser-compat-data/issues/9577
+		// Audio/video files use 'fetch' as browser support varies
 		return "fetch";
 	}
 	return "fetch";