From 9eea382185f481b43bea852008edb686f8a2e3d4 Mon Sep 17 00:00:00 2001
From: gudzpoz <gudzpoz@live.com>
Date: Fri, 28 Jun 2024 17:11:21 +0800
Subject: [PATCH] feat: always check stack size when popping

---
 .../src/main/java/party/iroiro/luajava/LuaTestSuite.java    | 4 ++++
 luajava/src/main/java/party/iroiro/luajava/AbstractLua.java | 6 ++++++
 2 files changed, 10 insertions(+)

diff --git a/example/suite/src/main/java/party/iroiro/luajava/LuaTestSuite.java b/example/suite/src/main/java/party/iroiro/luajava/LuaTestSuite.java
index 1a768c64..d80c75e5 100644
--- a/example/suite/src/main/java/party/iroiro/luajava/LuaTestSuite.java
+++ b/example/suite/src/main/java/party/iroiro/luajava/LuaTestSuite.java
@@ -684,6 +684,10 @@ private void testStackOperations() {
         try (Lua L = constructor.get()) {
             assertEquals(0, L.getTop());
             assertEquals(0, L.newThread().getTop());
+            assertThrowsLua(LuaError.MEMORY, () -> L.pop(-1), "invalid number of items to pop");
+            assertThrowsLua(LuaError.MEMORY, () -> L.pop(10), "invalid number of items to pop");
+            L.setTop(0);
+            assertThrowsLua(LuaError.MEMORY, () -> L.pop(1), "invalid number of items to pop");
         }
 
         Lua sub = L.newThread();
diff --git a/luajava/src/main/java/party/iroiro/luajava/AbstractLua.java b/luajava/src/main/java/party/iroiro/luajava/AbstractLua.java
index 3a5893ef..46a812a2 100644
--- a/luajava/src/main/java/party/iroiro/luajava/AbstractLua.java
+++ b/luajava/src/main/java/party/iroiro/luajava/AbstractLua.java
@@ -547,6 +547,12 @@ public void insert(int index) {
 
     @Override
     public void pop(int n) {
+        if (n < 0 || getTop() < n) {
+            throw new LuaException(
+                    LuaException.LuaError.MEMORY,
+                    "invalid number of items to pop"
+            );
+        }
         C.lua_pop(L, n);
     }