From a6ed00ad33d4218ac3b3bcdceee9e2604abbab45 Mon Sep 17 00:00:00 2001
From: Filip Tibell <filip.tibell@gmail.com>
Date: Sat, 29 Apr 2023 11:02:46 +0200
Subject: [PATCH] Fix _G

---
 CHANGELOG.md                     |  2 ++
 packages/lib/src/importer/mod.rs |  3 +--
 packages/lib/src/lua/create.rs   |  3 +++
 packages/lib/src/tests.rs        |  1 +
 tests/globals/_G.luau            | 20 ++++++++++++++++++++
 5 files changed, 27 insertions(+), 2 deletions(-)
 create mode 100644 tests/globals/_G.luau

diff --git a/CHANGELOG.md b/CHANGELOG.md
index d2b99e8..916b032 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -25,6 +25,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+-   Fixed `_G` not being a readable & writable table
+-   Fixed `_G` containing normal globals such as `print`, `math`, ...
 -   Fixed using instances as keys in tables
 
 ## `0.6.5` - March 27th, 2023
diff --git a/packages/lib/src/importer/mod.rs b/packages/lib/src/importer/mod.rs
index e1fb93b..50802f1 100644
--- a/packages/lib/src/importer/mod.rs
+++ b/packages/lib/src/importer/mod.rs
@@ -40,11 +40,10 @@ pub fn create(lua: &'static Lua, args: Vec<String>) -> LuaResult<()> {
         ("printinfo", lua.create_function(top_level::printinfo)?),
     ];
 
-    // Set top-level globals and seal them
+    // Set top-level globals
     for (name, global) in globals {
         lua_globals.set(name, global)?;
     }
-    lua_globals.set_readonly(true);
 
     Ok(())
 }
diff --git a/packages/lib/src/lua/create.rs b/packages/lib/src/lua/create.rs
index c618adc..cde5f2e 100644
--- a/packages/lib/src/lua/create.rs
+++ b/packages/lib/src/lua/create.rs
@@ -81,6 +81,9 @@ pub fn create() -> LuaResult<&'static Lua> {
     let table: LuaTable = globals.raw_get("table")?;
     let string: LuaTable = globals.raw_get("string")?;
     let coroutine: LuaTable = globals.get("coroutine")?;
+    // Create a _G table that is separate from our built-in globals
+    let global_table = lua.create_table()?;
+    globals.set("_G", global_table)?;
     // Store original lua global functions in the registry so we can use
     // them later without passing them around and dealing with lifetimes
     lua.set_named_registry_value("print", globals.get::<_, LuaFunction>("print")?)?;
diff --git a/packages/lib/src/tests.rs b/packages/lib/src/tests.rs
index 846b88c..f66232f 100644
--- a/packages/lib/src/tests.rs
+++ b/packages/lib/src/tests.rs
@@ -69,6 +69,7 @@ create_tests! {
     require_nested: "require/tests/nested",
     require_parents: "require/tests/parents",
     require_siblings: "require/tests/siblings",
+    global_g_table: "globals/_G",
     // TODO: Uncomment this test, it is commented out right
     // now to let CI pass so that we can make a new release
     // global_coroutine: "globals/coroutine",
diff --git a/tests/globals/_G.luau b/tests/globals/_G.luau
new file mode 100644
index 0000000..3011f54
--- /dev/null
+++ b/tests/globals/_G.luau
@@ -0,0 +1,20 @@
+assert(_G ~= nil, "Missing _G")
+
+assert(type(_G) == "table", "Invalid type for _G")
+
+assert(_G.require == nil, "Built-in global value was found in _G")
+assert(_G.print == nil, "Built-in global value was found in _G")
+assert(_G.warn == nil, "Built-in global value was found in _G")
+assert(_G.error == nil, "Built-in global value was found in _G")
+assert(_G.coroutine == nil, "Built-in global value was found in _G")
+assert(_G.typeof == nil, "Built-in global value was found in _G")
+assert(_G.type == nil, "Built-in global value was found in _G")
+
+assert(next(_G) == nil, "_G contained value but should be empty")
+
+_G.Hello = "World"
+assert(_G.Hello == "World", "Failed to set value in _G")
+
+local bar = {}
+_G.Foo = bar
+assert(_G.Foo == bar, "Failed to set reference in _G")