From 538682edf817424da67e3ae35f6268e659dbf073 Mon Sep 17 00:00:00 2001
From: Martin Klepsch <martinklepsch@googlemail.com>
Date: Wed, 13 Mar 2024 22:16:32 +0200
Subject: [PATCH] use unicode-resilient approach to exclude sub delimiters

---
 src/encoding.ts   | 22 ++++++++++++++++++----
 test/main.test.ts | 11 +++++++++++
 2 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/src/encoding.ts b/src/encoding.ts
index 8f27702..9df22fc 100644
--- a/src/encoding.ts
+++ b/src/encoding.ts
@@ -13,8 +13,6 @@
               / "*" / "+" / "," / ";" / "="
  */
 
-const excludeSubDelimiters = /[^!$'()*+,;|:]/g
-
 export type URLParamsEncodingType =
   | 'default'
   | 'uri'
@@ -22,8 +20,24 @@ export type URLParamsEncodingType =
   | 'none'
   | 'legacy'
 
-export const encodeURIComponentExcludingSubDelims = (segment: string): string =>
-  segment.replace(excludeSubDelimiters, match => encodeURIComponent(match))
+export const encodeURIComponentExcludingSubDelims = (
+  segment: string
+): string => {
+  // Define sub-delimiters to exclude from encoding
+  const subDelimiters = /[!$'()*+,;|:]/g
+
+  // Use Array.from to correctly handle characters represented by surrogate pairs
+  return Array.from(segment)
+    .map(char => {
+      // Check if the character is a sub-delimiter
+      if (subDelimiters.test(char)) {
+        return char // Return the character as is if it's a sub-delimiter
+      } else {
+        return encodeURIComponent(char) // Otherwise, encode it
+      }
+    })
+    .join('') // Join the array back into a string
+}
 
 const encodingMethods: Record<
   URLParamsEncodingType,
diff --git a/test/main.test.ts b/test/main.test.ts
index c997e06..de8a1fc 100644
--- a/test/main.test.ts
+++ b/test/main.test.ts
@@ -50,6 +50,17 @@ describe('Path', () => {
     )
   })
 
+  it('should match and build paths with emojis in query parameters', () => {
+    const pathA = new Path('/home?emoji')
+
+    expect(pathA.build({ emoji: '🤗' })).toEqual('/home?emoji=%F0%9F%A4%97')
+
+    const path = new Path('/home?emoji')
+    expect(path.test('/home?emoji=%F0%9F%99%8C')).toEqual({
+      emoji: '🙌'
+    })
+  })
+
   it('should match and build paths with query parameters', () => {
     const path = new Path('/users?offset&limit', {
       queryParams: { booleanFormat: 'string' }