perf: speed up resource parsing

.github/workflows/test.yml

@@ -55,7 +55,14 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
           architecture: ${{ steps.calculate_architecture.outputs.result }}
-          cache: ${{ matrix.node-version == '6.x' && '' || 'npm' }}
+        if: matrix.node-version == '6.x'
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node-version }}
+          architecture: ${{ steps.calculate_architecture.outputs.result }}
+          cache: "npm"
+        if: matrix.node-version != '6.x'
       - run: |
           sudo npm i npm@6.x
           sudo npm install --ignore-engines

lib/LoaderRunner.js

@@ -20,19 +20,60 @@ function utf8BufferToString(buf) {
 }
 
 const PATH_QUERY_FRAGMENT_REGEXP =
-	/^((?:\0.|[^?#\0])*)(\?(?:\0.|[^#\0])*)?(#.*)?$/;
+	/^(#?(?:\0.|[^?#\0])*)(\?(?:\0.|[^#\0])*)?(#.*)?$/;
+const ZERO_ESCAPE_REGEXP = /\0(.)/g;
 
 /**
- * @param {string} str the path with query and fragment
- * @returns {{ path: string, query: string, fragment: string }} parsed parts
+ * @param {string} identifier identifier
+ * @returns {[string, string, string]} parsed identifier
  */
-function parsePathQueryFragment(str) {
-	const match = PATH_QUERY_FRAGMENT_REGEXP.exec(str);
-	return {
-		path: match[1].replace(/\0(.)/g, "$1"),
-		query: match[2] ? match[2].replace(/\0(.)/g, "$1") : "",
-		fragment: match[3] || "",
-	};
+function parseIdentifier(identifier) {
+	const firstEscape = identifier.indexOf("\0");
+
+	if (firstEscape < 0) {
+		// Fast path for inputs that don't use \0 escaping.
+		const queryStart = identifier.indexOf("?");
+		// Start at index 1 to ignore a possible leading hash.
+		const fragmentStart = identifier.indexOf("#");
+
+		if (fragmentStart < 0) {
+			if (queryStart < 0) {
+				// No fragment, no query
+				return [identifier, "", ""];
+			}
+
+			// Query, no fragment
+			return [
+				identifier.slice(0, queryStart),
+				identifier.slice(queryStart),
+				"",
+			];
+		}
+
+		if (queryStart < 0 || fragmentStart < queryStart) {
+			// Fragment, no query
+			return [
+				identifier.slice(0, fragmentStart),
+				"",
+				identifier.slice(fragmentStart),
+			];
+		}
+
+		// Query and fragment
+		return [
+			identifier.slice(0, queryStart),
+			identifier.slice(queryStart, fragmentStart),
+			identifier.slice(fragmentStart),
+		];
+	}
+
+	const match = PATH_QUERY_FRAGMENT_REGEXP.exec(identifier);
+
+	return [
+		match[1].replace(ZERO_ESCAPE_REGEXP, "$1"),
+		match[2] ? match[2].replace(ZERO_ESCAPE_REGEXP, "$1") : "",
+		match[3] || "",
+	];
 }
 
 function dirname(path) {
@@ -73,10 +114,10 @@ function createLoaderObject(loader) {
 		},
 		set(value) {
 			if (typeof value === "string") {
-				const splittedRequest = parsePathQueryFragment(value);
-				obj.path = splittedRequest.path;
-				obj.query = splittedRequest.query;
-				obj.fragment = splittedRequest.fragment;
+				const [path, query, fragment] = parseIdentifier(value);
+				obj.path = path;
+				obj.query = query;
+				obj.fragment = fragment;
 				obj.options = undefined;
 				obj.ident = undefined;
 			} else {
@@ -298,7 +339,7 @@ function iteratePitchingLoaders(options, loaderContext, callback) {
 }
 
 module.exports.getContext = function getContext(resource) {
-	const { path } = parsePathQueryFragment(resource);
+	const [path] = parseIdentifier(resource);
 	return dirname(path);
 };
 
@@ -314,10 +355,10 @@ module.exports.runLoaders = function runLoaders(options, callback) {
 			readResource(resource, callback);
 		}).bind(null, options.readResource || readFile);
 
-	const splittedResource = resource && parsePathQueryFragment(resource);
-	const resourcePath = splittedResource ? splittedResource.path : "";
-	const resourceQuery = splittedResource ? splittedResource.query : "";
-	const resourceFragment = splittedResource ? splittedResource.fragment : "";
+	const splittedResource = resource && parseIdentifier(resource);
+	const resourcePath = splittedResource ? splittedResource[0] : "";
+	const resourceQuery = splittedResource ? splittedResource[1] : "";
+	const resourceFragment = splittedResource ? splittedResource[2] : "";
 	const contextDirectory = resourcePath ? dirname(resourcePath) : null;
 
 	// execution state
@@ -378,15 +419,15 @@ module.exports.runLoaders = function runLoaders(options, callback) {
 			);
 		},
 		set(value) {
-			const splittedResource = value && parsePathQueryFragment(value);
+			const splittedResource = value && parseIdentifier(value);
 			loaderContext.resourcePath = splittedResource
-				? splittedResource.path
+				? splittedResource[0]
 				: undefined;
 			loaderContext.resourceQuery = splittedResource
-				? splittedResource.query
+				? splittedResource[1]
 				: undefined;
 			loaderContext.resourceFragment = splittedResource
-				? splittedResource.fragment
+				? splittedResource[2]
 				: undefined;
 		},
 	});