Tagged userdata headers (#262)

Closes #261 by creating a `userdatas.h` header file under the Runtime
folder, and switching the `Duration` and `Instant` userdatas to be
tagged.

Author: ffrostfall

Sources.cmake

@@ -4,6 +4,7 @@ target_sources(Lute.Runtime PRIVATE
     runtime/include/lute/require.h
     runtime/include/lute/requireutils.h
     runtime/include/lute/runtime.h
+    runtime/include/lute/userdatas.h
 
     runtime/src/options.cpp
     runtime/src/ref.cpp

luau/src/luau.cpp

@@ -8,6 +8,9 @@
 #include "Luau/ToString.h"
 #include "Luau/Compiler.h"
 
+#include "lute/userdatas.h"
+
+
 #include "lua.h"
 #include "lualib.h"
 #include <cstddef>
@@ -1707,7 +1710,7 @@ struct AstSerialize : public Luau::AstVisitor
         node->type->visit(this);
         lua_setfield(L, -2, "type");
 
-        serializeToken(Luau::Position{node->location.end.line, node->location.end.column -1}, ")");
+        serializeToken(Luau::Position{node->location.end.line, node->location.end.column - 1}, ")");
         lua_setfield(L, -2, "closeParens");
     }
 
@@ -2190,7 +2193,7 @@ int compile_luau(lua_State* L)
 
     std::string bytecode = Luau::compile(std::string(source, source_size), opts);
 
-    std::string* userdata = static_cast<std::string*>(lua_newuserdata(L, sizeof(std::string)));
+    std::string* userdata = static_cast<std::string*>(lua_newuserdatatagged(L, sizeof(std::string), kCompilerResultTag));
 
     new (userdata) std::string(std::move(bytecode));
 

runtime/include/lute/userdatas.h

@@ -0,0 +1,5 @@
+#pragma once
+
+const int kDurationTag = 1;
+const int kInstantTag = 2;
+const int kCompilerResultTag = 3;

time/include/lute/time.h

@@ -9,9 +9,6 @@ int luaopen_time(lua_State* L);
 // open the library as a table on top of the stack
 int luteopen_time(lua_State* L);
 
-static const int kDurationTag = 2;
-static const int kInstantTag = 1;
-
 static const char kInstantType[] = "instant";
 static const char kDurationType[] = "duration";
 static const char kDurationLibraryIdentifier[] = "duration";

time/src/time.cpp

@@ -1,6 +1,7 @@
 #include "lute/time.h"
 #include "lua.h"
 #include "lualib.h"
+#include "lute/userdatas.h"
 #include "uv.h"
 
 #include <cmath>