Add support for lua.getField(), lua.setField(), lua.getGlobal(), lua.setGlobal()

Author: thsackos

README.md

@@ -78,8 +78,8 @@ lua.doString(
 
 | API | Support |
 |---|---|
-| Lua C API (`lua_*`) | 58% available (55/92) | <!-- 59.76% - Add 1.07 per -->
-| Auxilary Library (`luaL_*`) | 6% available (3/48) | <!-- Always 2% * n, for n up to 48 -->
+| Lua C API (`lua_*`) | 64% available (59/92) |
+| Auxilary Library (`luaL_*`) | 6% available (3/48) |
 | LuaJIT Extensions | *No plans to implement.* |
 
 ## C API Coverage (`lua_`)
@@ -119,8 +119,8 @@ pattern has changed, such as using the Zig `init()` function pattern instead of
 | `lua_gc`||
 | `lua_getallocf`| ➖ `lua.getAllocF()` |
 | `lua_getfenv`||
-| `lua_getfield`||
-| `lua_getglobal`||
+| `lua_getfield`| ☑️ `lua.getField()` |
+| `lua_getglobal`| ☑️ `lua.getGlobal()` |
 | `lua_getmetatable`| ☑️ `lua.getMetatable()` |
 | `lua_gettable`| ☑️ `lua.getTable()` |
 | `lua_gettop`| ☑️ `lua.getTop()` |
@@ -172,8 +172,8 @@ pattern has changed, such as using the Zig `init()` function pattern instead of
 | `lua_resume`||
 | `lua_setallocf`|➖ `lua.setAllocF()`|
 | `lua_setfenv`||
-| `lua_setfield`||
-| `lua_setglobal`||
+| `lua_setfield`| ☑️ `lua.setField()` |
+| `lua_setglobal`| ☑️ `lua.setGlobal()` |
 | `lua_setmetatable`| ☑️ `lua.setMetatable()` |
 | `lua_settable`| ☑️ `lua.setTable()` |
 | `lua_settop`| ☑️ `lua.setTop()` |

src/lua_api.zig

@@ -41,21 +41,6 @@ pub const GcMode = enum(i32) {
 /// Stack Behavior: `[-0, +1, -]`
 pub fn getfenv(lua: *Lua, index: i32) void;
 
-/// Pushes onto the stack the value t[k], where t is the value at the given valid index.
-/// As in Lua, this function may trigger a metamethod for the "index" event (see https://www.lua.org/manual/5.1/manual.html#2.8).
-///
-/// From: `void lua_getfield(lua_State *L, int index, const char *k);`
-/// Refer to: https://www.lua.org/manual/5.1/manual.html#lua_getfield
-/// Stack Behavior: `[-0, +1, e]`
-pub fn getField(lua: *Lua, index: i32, k: [:0]const u8) LuaType;
-
-/// Pushes onto the stack the value of the global name.
-///
-/// From: `void lua_getglobal(lua_State *L, const char *name);`
-/// Refer to: https://www.lua.org/manual/5.1/manual.html#lua_getglobal
-/// Stack Behavior: `[-0, +1, e]`
-pub fn getGlobal(lua: *Lua, name: [*:0]const u8) LuaType;
-
 /// The type used by the Lua API to represent integral values. 
 /// By default it is a signed integral type that the machine handles "comfortably".
 ///
@@ -248,22 +233,6 @@ pub fn resumeCoroutine(lua: *Lua, narg: i32) i32;
 /// Stack Behavior: `[-1, +0, -]`
 pub fn setFenv(lua: *Lua, index: i32) bool;
 
-/// Does the equivalent to t[k] = v, where t is the value at the given valid index and v is the value at the 
-/// top of the stack. This function pops the value from the stack. As in Lua, this function may trigger a 
-/// metamethod for the "newindex" event (see https://www.lua.org/manual/5.1/manual.html#2.8).
-///
-/// From: `void lua_setfield(lua_State *L, int index, const char *k);`
-/// Refer to: https://www.lua.org/manual/5.1/manual.html#lua_setfield
-/// Stack Behavior: `[-1, +0, e]`
-pub fn setField(lua: *Lua, index: i32, key: [:0]const u8) void;
-
-/// Pops a value from the stack and sets it as the new value of global `name`.
-///
-/// From: `void lua_setglobal(lua_State *L, const char *name);`
-/// Refer to: https://www.lua.org/manual/5.1/manual.html#lua_setglobal
-/// Stack Behavior: `[-1, +0, e]`
-pub fn setGlobal(lua: *Lua, name: [:0]const u8) void;
-
 /// Opaque structure that keeps the whole state of a Lua interpreter. The Lua library is fully reentrant:
 /// it has no global variables. All information about a state is kept in this structure. A pointer
 /// to this state must be passed as the first argument to every function in the library, except 

src/root.zig

@@ -851,6 +851,53 @@ pub const Lua = opaque {
         return 1 == c.lua_getmetatable(asState(lua), index);
     }
 
+    /// Pushes onto the stack the value `t[k]`, where `t` is the value at the given valid index. As in Lua, this function
+    /// may trigger a metamethod for the "index" event (see https://www.lua.org/manual/5.1/manual.html#2.8).
+    ///
+    /// From: `void lua_getfield(lua_State *L, int index, const char *k);`
+    /// Refer to: https://www.lua.org/manual/5.1/manual.html#lua_getfield
+    /// Stack Behavior: `[-0, +1, e]`
+    pub fn getField(lua: *Lua, index: i32, key: [:0]const u8) Lua.Type {
+        lua.validateStackIndex(index);
+
+        c.lua_getfield(asState(lua), index, @ptrCast(key.ptr));
+        return lua.typeOf(-1);
+    }
+
+    /// Does the equivalent to `t[k] = v`, where `t` is the value at the given valid index and `v` is the value at the
+    /// top of the stack. This function pops the value from the stack. As in Lua, this function may trigger a
+    /// metamethod for the "newindex" event (see https://www.lua.org/manual/5.1/manual.html#2.8).
+    ///
+    /// From: `void lua_setfield(lua_State *L, int index, const char *k);`
+    /// Refer to: https://www.lua.org/manual/5.1/manual.html#lua_setfield
+    /// Stack Behavior: `[-1, +0, e]`
+    pub fn setField(lua: *Lua, index: i32, key: [:0]const u8) void {
+        lua.validateStackIndex(index);
+
+        return c.lua_setfield(asState(lua), index, @ptrCast(key.ptr));
+    }
+
+    /// Pushes onto the stack the value of the global name.
+    ///
+    /// From: `void lua_getglobal(lua_State *L, const char *name);`
+    /// Refer to: https://www.lua.org/manual/5.1/manual.html#lua_getglobal
+    /// Stack Behavior: `[-0, +1, e]`
+    pub fn getGlobal(lua: *Lua, name: [:0]const u8) Lua.Type {
+        c.lua_getglobal(asState(lua), @as([*:0]const u8, @ptrCast(name.ptr)));
+        return lua.typeOf(-1);
+    }
+
+    /// Pops a value from the stack and sets it as the new value of global `name`.
+    ///
+    /// From: `void lua_setglobal(lua_State *L, const char *name);`
+    /// Refer to: https://www.lua.org/manual/5.1/manual.html#lua_setglobal
+    /// Stack Behavior: `[-1, +0, e]`
+    pub fn setGlobal(lua: *Lua, name: [:0]const u8) void {
+        assert(lua.getTop() > 0);
+
+        return c.lua_setglobal(asState(lua), @as([*:0]const u8, @ptrCast(name.ptr)));
+    }
+
     /// Does the equivalent of `t[k] = v`, where `t` is the acceptable index of the table on the stack, `v` is
     /// the value at the top of the stack, and `k` is the value just below the top. This function pops both the
     /// key and the value from the stack. As in Lua, this function may trigger a metamethod for the "newindex"
@@ -1701,6 +1748,35 @@ test "tables" {
     try std.testing.expectEqual(Lua.Type.string, lua.getTableRaw(-2));
 }
 
+test "getfield and setfield" {
+    const lua = try Lua.init(std.testing.allocator);
+    defer lua.deinit();
+
+    lua.newTable();
+    lua.pushInteger(42);
+    lua.setField(-2, "foo");
+
+    try std.testing.expectEqual(1, lua.getTop());
+
+    const actual_type = lua.getField(-1, "foo");
+    try std.testing.expectEqual(Lua.Type.number, actual_type);
+    try std.testing.expectEqual(42, lua.toInteger(-1));
+}
+
+test "getglobal and setglobal" {
+    const lua = try Lua.init(std.testing.allocator);
+    defer lua.deinit();
+
+    lua.pushInteger(42);
+    lua.setGlobal("XXX");
+
+    try std.testing.expectEqual(0, lua.getTop());
+
+    const actual_type = lua.getGlobal("XXX");
+    try std.testing.expectEqual(Lua.Type.number, actual_type);
+    try std.testing.expectEqual(42, lua.toInteger(-1));
+}
+
 test "lengthOf" {
     const lua = try Lua.init(std.testing.allocator);
     defer lua.deinit();