Fix std::filesystem::path - to - std::string conversions on Windows.

On Windows, std::filesystem::path::value_type is wchar_t, not char -- so
path::string_type is std::wstring, not std::string. So while Posix path
instances implicitly convert to string, Windows path instances do not. Add
explicit u8string() calls.

Also add LL.abspath() Lua entry point to further facilitate finding a resource
file relative to the calling Lua script. Use abspath() for both
test_luafloater_demo.lua and test_luafloater_gesture_list.lua.

1 files changed, 14 insertions, 2 deletions

diff --git a/indra/llcommon/lua_function.cpp b/indra/llcommon/lua_function.cpp
index 96282df554..cd83f40e85 100644
--- a/indra/llcommon/lua_function.cpp
+++ b/indra/llcommon/lua_function.cpp
@@ -711,7 +711,7 @@ std::pair<LuaFunction::Registry&, LuaFunction::Lookup&> LuaFunction::getState()
 lua_function(source_path, "return the source path of the running Lua script")
 {
     luaL_checkstack(L, 1, nullptr);
-    lua_pushstdstring(L, lluau::source_path(L));
+    lua_pushstdstring(L, lluau::source_path(L).u8string());
     return 1;
 }
 
@@ -721,7 +721,19 @@ lua_function(source_path, "return the source path of the running Lua script")
 lua_function(source_dir, "return the source directory of the running Lua script")
 {
     luaL_checkstack(L, 1, nullptr);
-    lua_pushstdstring(L, lluau::source_path(L).parent_path());
+    lua_pushstdstring(L, lluau::source_path(L).parent_path().u8string());
+    return 1;
+}
+
+/*****************************************************************************
+*   abspath()
+*****************************************************************************/
+lua_function(abspath,
+             "for given filesystem path relative to running script, return absolute path")
+{
+    auto path{ lua_tostdstring(L, 1) };
+    lua_pop(L, 1);
+    lua_pushstdstring(L, (lluau::source_path(L).parent_path() / path).u8string());
     return 1;
 }