From f69d8b75c80ec067fb5fa2c411e59fbf792236db Mon Sep 17 00:00:00 2001
From: roytam1 <roytam@gmail.com>
Date: Mon, 1 May 2023 07:22:50 +0800
Subject: [PATCH] import from UXP: Issue #1285 - Follow-up: Correctly handle
 follow-up compilations of RegExp with named capturing groups (0a74a575)

---
 js/src/vm/RegExpObject.cpp | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/js/src/vm/RegExpObject.cpp b/js/src/vm/RegExpObject.cpp
index cc1ef6418..a66d86ff5 100644
--- a/js/src/vm/RegExpObject.cpp
+++ b/js/src/vm/RegExpObject.cpp
@@ -996,11 +996,33 @@ RegExpShared::initializeNamedCaptures(JSContext* cx, HandleRegExpShared re,
                                       irregexp::CharacterVectorVector* names,
                                       irregexp::IntegerVector* indices)
 {
-    MOZ_ASSERT(!re->groupsTemplate_);
     MOZ_ASSERT(names);
     MOZ_ASSERT(indices);
     MOZ_ASSERT(names->length() == indices->length());
 
+    if (re->getGroupsTemplate()) {
+        // If initializeNamedCaptures was previously called for a different CompilationMode/Latin1Chars combination,
+        // the template object is already created and correct.
+#ifdef DEBUG
+        // In debug builds, verify that.
+        MOZ_ASSERT(re->getGroupsTemplate()->propertyCount() == names->length());
+        RootedId id(cx);
+        RootedNativeObject groupsTemplate(cx, re->getGroupsTemplate());
+        Rooted<PropertyDescriptor> desc(cx);
+        for (uint32_t i = 0; i < names->length(); i++) {
+            irregexp::CharacterVector* cv = (*names)[i];
+            JSAtom* atom = AtomizeChars(cx, cv->begin(), cv->length());
+            MOZ_ASSERT(atom);
+            id = NameToId(atom->asPropertyName());
+            MOZ_ASSERT(NativeGetOwnPropertyDescriptor(cx, groupsTemplate, id, &desc));
+            int32_t idx;
+            MOZ_ASSERT(ToInt32(cx, desc.value(), &idx));
+            MOZ_ASSERT(idx == (*indices)[i]);
+        }
+#endif
+        return true;
+    }
+
     // The irregexp parser returns named capture information in the form
     // of two arrays. We create a template object with a property for each
     // capture name, and store the capture index as Integer in the corresponding value.
@@ -1027,7 +1049,7 @@ RegExpShared::initializeNamedCaptures(JSContext* cx, HandleRegExpShared re,
         // Need to explicitly create an Atom (not a String) or it won't get added to the atom table
         JSAtom* atom = AtomizeChars(cx, cv->begin(), cv->length());
         if (!atom) {
-          return false;
+            return false;
         }
         id = NameToId(atom->asPropertyName());
         RootedValue idx(cx, Int32Value((*indices)[i]));