From a7ee0c27e73afceeb3ee201e0ae7051481530edd Mon Sep 17 00:00:00 2001
From: Eduardo Speroni <edusperoni@gmail.com>
Date: Fri, 3 Jul 2026 12:00:02 -0300
Subject: [PATCH] fix(urlpattern): match capture groups in test()/exec()

v8_regex_provider::regex_search had two bugs that made URLPattern matching
fail (or crash) for any pattern with capture groups:

- The ToLocal(&item) success check was inverted, so the first successfully
  read match element bailed out as "no match" and test()/exec() always
  returned false/null.
- It included match element 0 (the whole-match string). ada's
  create_component_match_result pairs exec_result[i] with group_name_list[i]
  and expects only the capture groups, so the extra element overran
  group_name_list and crashed once the inverted check was fixed.

Iterate from index 1 and bail only when reading an element fails.

Add URLPattern regression tests covering test() match/non-match and exec()
named capture-group extraction and null-on-no-match.
---
 NativeScript/runtime/URLPatternImpl.cpp | 14 ++++++++++++--
 TestRunner/app/tests/URLPattern.js      | 19 +++++++++++++++++++
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/NativeScript/runtime/URLPatternImpl.cpp b/NativeScript/runtime/URLPatternImpl.cpp
index 4b4435f5..5ffe5a6a 100644
--- a/NativeScript/runtime/URLPatternImpl.cpp
+++ b/NativeScript/runtime/URLPatternImpl.cpp
@@ -73,9 +73,19 @@ v8_regex_provider::regex_search(
     auto array = matches.As<v8::Array>();
     auto len = array->Length();
     ret.reserve(len);
-    for (int i = 0; i < len; i++) {
+    // Skip element 0 (the whole-match string). ada's
+    // url_pattern_component::create_component_match_result pairs exec_result[i]
+    // with group_name_list[i], i.e. it expects only the capture groups.
+    // Including element 0 makes exec_result one longer than group_name_list and
+    // indexes it out of bounds (crash). ada documents this: the provider must
+    // drop the full match ("start from 1").
+    for (int i = 1; i < len; i++) {
       v8::Local<v8::Value> item;
-      if (array->Get(isolate->GetCurrentContext(), i).ToLocal(&item)) {
+      // ToLocal returns true on success; bail only when reading the element
+      // fails. (This condition was inverted, which made every regex match
+      // report no match, so URLPattern test()/exec() always failed for patterns
+      // with capture groups.)
+      if (!array->Get(isolate->GetCurrentContext(), i).ToLocal(&item)) {
         return std::nullopt;
       }
 
diff --git a/TestRunner/app/tests/URLPattern.js b/TestRunner/app/tests/URLPattern.js
index 0c2d1c1f..889e33cb 100644
--- a/TestRunner/app/tests/URLPattern.js
+++ b/TestRunner/app/tests/URLPattern.js
@@ -46,4 +46,23 @@ describe("URLPattern", function () {
     expect(pattern.hostname).toBe("google.com");
   });
 
+  it("test() matches a URL against a pattern with a capture group", function () {
+    const pattern = new URLPattern("https://example.com/books/:id");
+    expect(pattern.test("https://example.com/books/123")).toBe(true);
+    expect(pattern.test("https://example.com/movies/123")).toBe(false);
+  });
+
+  it("exec() extracts named capture groups", function () {
+    const pattern = new URLPattern("https://example.com/books/:id");
+    const result = pattern.exec("https://example.com/books/123");
+    expect(result).not.toBeNull();
+    expect(result.pathname.input).toBe("/books/123");
+    expect(result.pathname.groups.id).toBe("123");
+  });
+
+  it("exec() returns null when the URL does not match", function () {
+    const pattern = new URLPattern("https://example.com/books/:id");
+    expect(pattern.exec("https://example.com/movies/123")).toBeNull();
+  });
+
 });