refactor(router-core): utils/decodePath minor performance improvements

packages/router-core/src/utils.ts

@@ -489,64 +489,63 @@ export function findLast<T>(
   return undefined
 }
 
-const DECODE_IGNORE_LIST = Array.from(
-  new Map([
-    ['%', '%25'],
-    ['\\', '%5C'],
-  ]).values(),
-)
+const DECODE_IGNORE_LIST = [
+  '%25', // %
+  '%5C', // \
+]
 
-export function decodePath(
+function splitAndDecode(
   part: string,
-  decodeIgnore: Array<string> = DECODE_IGNORE_LIST,
+  decodeIgnore: Array<string>,
+  startIndex = 0,
 ): string {
-  function splitAndDecode(
-    part: string,
-    decodeIgnore: Array<string>,
-    startIndex = 0,
-  ): string {
-    // decode the path / path segment by splitting it into parts defined by the ignore list.
-    // once these pieces have been decoded, join them back together to form the final decoded path segment with the ignored character in place.
-    // we walk through the ignore list linearly, breaking the segment up into pieces and decoding each piece individually.
-    // use index traversal to avoid making unnecessary copies of the array.
-    for (let i = startIndex; i < decodeIgnore.length; i++) {
-      const char = decodeIgnore[i]!.toUpperCase()
-
-      // check if the part includes the current ignore character
-      // if it doesn't continue to the next ignore character
-      if (part.includes(char)) {
-        // split the part into pieces that needs to be checked and decoded
-        const partsToDecode = part.split(char)
-        const partsToJoin: Array<string> = []
-
-        // now check and decode each piece individually taking into consideration the remaining ignored characters.
-        // since we are walking through the list linearly, we only need to consider ignore items not yet traversed.
-        for (const partToDecode of partsToDecode) {
-          // once we have traversed the entire ignore list, each decoded part is returned.
-          partsToJoin.push(splitAndDecode(partToDecode, decodeIgnore, i + 1))
-        }
-
-        // and join them back together to form the final decoded path segment with the ignored character in place.
-        return partsToJoin.join(char)
+  // decode the path / path segment by splitting it into parts defined by the ignore list.
+  // once these pieces have been decoded, join them back together to form the final decoded path segment with the ignored character in place.
+  // we walk through the ignore list linearly, breaking the segment up into pieces and decoding each piece individually.
+  // use index traversal to avoid making unnecessary copies of the array.
+  for (let i = startIndex; i < decodeIgnore.length; i++) {
+    const char = decodeIgnore[i]!.toUpperCase()
+
+    // check if the part includes the current ignore character
+    // if it doesn't continue to the next ignore character
+    if (part.includes(char)) {
+      // split the part into pieces that needs to be checked and decoded
+      const partsToDecode = part.split(char)
+      const partsToJoin = new Array<string>(partsToDecode.length)
+
+      // now check and decode each piece individually taking into consideration the remaining ignored characters.
+      // since we are walking through the list linearly, we only need to consider ignore items not yet traversed.
+      for (let j = 0; j < partsToDecode.length; j++) {
+        const partToDecode = partsToDecode[j]!
+        // once we have traversed the entire ignore list, each decoded part is returned.
+        partsToJoin[j] = splitAndDecode(partToDecode, decodeIgnore, i + 1)
       }
-    }
 
-    // once we have reached the end of the ignore list, we start walking back returning each decoded part.
-    // should there be no matching characters, the path segment as a whole will be decoded.
-    try {
-      return decodeURI(part)
-    } catch {
-      // if the decoding fails, try to decode the various parts leaving the malformed tags in place
-      return part.replaceAll(/%[0-9A-F]{2}/g, (match) => {
-        try {
-          return decodeURI(match)
-        } catch {
-          return match
-        }
-      })
+      // and join them back together to form the final decoded path segment with the ignored character in place.
+      return partsToJoin.join(char)
     }
   }
 
+  // once we have reached the end of the ignore list, we start walking back returning each decoded part.
+  // should there be no matching characters, the path segment as a whole will be decoded.
+  try {
+    return decodeURI(part)
+  } catch {
+    // if the decoding fails, try to decode the various parts leaving the malformed tags in place
+    return part.replaceAll(/%[0-9A-F]{2}/g, (match) => {
+      try {
+        return decodeURI(match)
+      } catch {
+        return match
+      }
+    })
+  }
+}
+
+export function decodePath(
+  part: string,
+  decodeIgnore: Array<string> = DECODE_IGNORE_LIST,
+): string {
   // if the path segment does not contain any encoded uri components return the path as is
   if (part === '' || !/%[0-9A-Fa-f]{2}/g.test(part)) return part