From 5806127294529c2e2a3bfaa552491a537f44ee58 Mon Sep 17 00:00:00 2001
From: paq <89paku@gmail.com>
Date: Mon, 11 May 2026 11:26:50 +0900
Subject: [PATCH 1/3] fix: align %p behavior with native C Lua

---
 src/Lua/Standard/Internal/MatchState.cs |  3 ++-
 tests/Lua.Tests/PatternMatchingTests.cs | 33 +++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/src/Lua/Standard/Internal/MatchState.cs b/src/Lua/Standard/Internal/MatchState.cs
index f9bbf718..b306ddac 100644
--- a/src/Lua/Standard/Internal/MatchState.cs
+++ b/src/Lua/Standard/Internal/MatchState.cs
@@ -460,7 +460,8 @@ static bool MatchClass(char c, char cl)
                 res = char.IsLower(c);
                 break;
             case 'p':
-                res = char.IsPunctuation(c);
+                // Emulate C ispunct; .NET's char.IsPunctuation does not include symbols like '='.
+                res = !char.IsLetterOrDigit(c) && !char.IsControl(c) && !char.IsWhiteSpace(c);
                 break;
             case 's':
                 res = char.IsWhiteSpace(c);
diff --git a/tests/Lua.Tests/PatternMatchingTests.cs b/tests/Lua.Tests/PatternMatchingTests.cs
index 7ddc6d9f..6411d3ea 100644
--- a/tests/Lua.Tests/PatternMatchingTests.cs
+++ b/tests/Lua.Tests/PatternMatchingTests.cs
@@ -597,6 +597,39 @@ public async Task Test_StringGSub_PatternReplacements()
         Assert.That(result[1].Read<double>(), Is.EqualTo(1));
     }
 
+    [Test]
+    public async Task Test_StringGSub_PunctuationClassCapturesSymbolCharacters()
+    {
+        var state = LuaState.Create();
+        state.OpenStringLibrary();
+
+        var result = await state.DoStringAsync(
+            """
+            local punctuation = [=[!"#$%&'()*+,-./
+            :;<=>?@
+            [\]^_`
+            {|}~]=]
+            local matched = ''
+            local count = 0
+            string.gsub(punctuation, '%p', function(c)
+                matched = matched .. c
+                count = count + 1
+            end)
+            return matched, count
+            """
+        );
+
+        Assert.That(result[0].Read<string>(), Is.EqualTo("!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~"));
+        Assert.That(result[1].Read<double>(), Is.EqualTo(32));
+
+        result = await state.DoStringAsync(
+            "return string.gsub('abc=xyz', '(%w*)(%p)(%w+)', '%3%2%1-%0')"
+        );
+
+        Assert.That(result[0].Read<string>(), Is.EqualTo("xyz=abc-abc=xyz"));
+        Assert.That(result[1].Read<double>(), Is.EqualTo(1));
+    }
+
     [Test]
     public async Task Test_StringGSub_FunctionReplacements()
     {

From 9a34b886ec6c90eb95fc62af614303b7ce02f20b Mon Sep 17 00:00:00 2001
From: paq <89paku@gmail.com>
Date: Sun, 31 May 2026 09:28:58 +0900
Subject: [PATCH 2/3] fix: align %p behavior with C ispunct exactly

---
 src/Lua/Standard/Internal/MatchState.cs |  5 ++++-
 tests/Lua.Tests/PatternMatchingTests.cs | 13 ++++++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/Lua/Standard/Internal/MatchState.cs b/src/Lua/Standard/Internal/MatchState.cs
index b306ddac..0204ab07 100644
--- a/src/Lua/Standard/Internal/MatchState.cs
+++ b/src/Lua/Standard/Internal/MatchState.cs
@@ -461,7 +461,10 @@ static bool MatchClass(char c, char cl)
                 break;
             case 'p':
                 // Emulate C ispunct; .NET's char.IsPunctuation does not include symbols like '='.
-                res = !char.IsLetterOrDigit(c) && !char.IsControl(c) && !char.IsWhiteSpace(c);
+                res = (c >= '!' && c <= '/') ||
+                      (c >= ':' && c <= '@') ||
+                      (c >= '[' && c <= '`') ||
+                      (c >= '{' && c <= '~');
                 break;
             case 's':
                 res = char.IsWhiteSpace(c);
diff --git a/tests/Lua.Tests/PatternMatchingTests.cs b/tests/Lua.Tests/PatternMatchingTests.cs
index 6411d3ea..146e8fc2 100644
--- a/tests/Lua.Tests/PatternMatchingTests.cs
+++ b/tests/Lua.Tests/PatternMatchingTests.cs
@@ -598,7 +598,7 @@ public async Task Test_StringGSub_PatternReplacements()
     }
 
     [Test]
-    public async Task Test_StringGSub_PunctuationClassCapturesSymbolCharacters()
+    public async Task Test_StringGSub_PunctuationClassCapturesAsciiSymbolCharacters()
     {
         var state = LuaState.Create();
         state.OpenStringLibrary();
@@ -622,6 +622,17 @@ public async Task Test_StringGSub_PunctuationClassCapturesSymbolCharacters()
         Assert.That(result[0].Read<string>(), Is.EqualTo("!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~"));
         Assert.That(result[1].Read<double>(), Is.EqualTo(32));
 
+        // Lua %p does not capture non-ASCII punctuation characters
+        result = await state.DoStringAsync(
+            """
+            local text = '’،。、！？'
+            return string.gsub(text, '%p', 'X')
+            """
+        );
+
+        Assert.That(result[0].Read<string>(), Is.EqualTo("’،。、！？"));
+        Assert.That(result[1].Read<double>(), Is.EqualTo(0));
+
         result = await state.DoStringAsync(
             "return string.gsub('abc=xyz', '(%w*)(%p)(%w+)', '%3%2%1-%0')"
         );

From f9a5f3a432793bf5d1636e7044ad25eef48c4339 Mon Sep 17 00:00:00 2001
From: akeit0 <90429982+Akeit0@users.noreply.github.com>
Date: Sun, 31 May 2026 20:02:16 +0900
Subject: [PATCH 3/3] run formatter

---
 src/Lua/Standard/Internal/MatchState.cs | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/Lua/Standard/Internal/MatchState.cs b/src/Lua/Standard/Internal/MatchState.cs
index 0204ab07..15874841 100644
--- a/src/Lua/Standard/Internal/MatchState.cs
+++ b/src/Lua/Standard/Internal/MatchState.cs
@@ -461,10 +461,12 @@ static bool MatchClass(char c, char cl)
                 break;
             case 'p':
                 // Emulate C ispunct; .NET's char.IsPunctuation does not include symbols like '='.
-                res = (c >= '!' && c <= '/') ||
-                      (c >= ':' && c <= '@') ||
-                      (c >= '[' && c <= '`') ||
-                      (c >= '{' && c <= '~');
+                res =
+                    c
+                        is (>= '!' and <= '/')
+                            or (>= ':' and <= '@')
+                            or (>= '[' and <= '`')
+                            or (>= '{' and <= '~');
                 break;
             case 's':
                 res = char.IsWhiteSpace(c);