luaL_newstate, lua_pushnil, lua_gettop, luaL_typename

5 files changed, 76 insertions, 21 deletions

diff --git a/README.md b/README.md
index ee33ad4..a21cb1b 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,9 @@
     - [x] lua_atpanic
     - [x] lua_newstate
     - [x] lua_pushnil
+    - [x] lua_gettop
+    - [x] lua_type
+    - [x] lua_typename
     - [ ] lua_absindex
     - [ ] lua_arith
     - [ ] lua_call
@@ -50,7 +53,6 @@
     - [ ] lua_getmetatable
     - [ ] lua_getstack
     - [ ] lua_gettable
-    - [ ] lua_gettop
     - [ ] lua_getupvalue
     - [ ] lua_getuservalue
     - [ ] lua_insert
@@ -129,8 +131,6 @@
     - [ ] lua_tostring
     - [ ] lua_tothread
     - [ ] lua_touserdata
-    - [ ] lua_type
-    - [ ] lua_typename
     - [ ] lua_upvalueid
     - [ ] lua_upvalueindex
     - [ ] lua_upvaluejoin
@@ -140,6 +140,7 @@
     - [ ] lua_yieldk
 - [ ] Auxiliary library
     - [x] luaL_newstate
+    - [x] luaL_typename
     - [ ] luaL_Buffer
     - [ ] luaL_Reg
     - [ ] luaL_Stream
@@ -198,7 +199,6 @@
     - [ ] luaL_testudata
     - [ ] luaL_tolstring
     - [ ] luaL_traceback
-    - [ ] luaL_typename
     - [ ] luaL_unref
     - [ ] luaL_where
 - [ ] Standard library
diff --git a/src/lapi.js b/src/lapi.js
index 9e20d7f..0cb0a4b 100644
--- a/src/lapi.js
+++ b/src/lapi.js
@@ -5,6 +5,7 @@ const assert    = require('assert');
 
 const ldo       = require('./ldo.js');
 const lobject   = require('./lobject.js');
+const ltm       = require('./ltm.js');
 const lfunc     = require('./lfunc.js');
 const lua       = require('./lua.js');
 const lstate    = require('./lstate.js');
@@ -49,6 +50,14 @@ const index2addr = function(L, idx) {
 
 };
 
+/*
+** basic stack manipulation
+*/
+
+const lua_gettop = function(L) {
+    return L.top - 1;
+};
+
 const lua_pushvalue = function(L, idx) {
     L.stack[L.top] = L.stack[index2addr(L, idx)];
 
@@ -164,6 +173,16 @@ const f_call = function(L, ud) {
     ldo.luaD_callnoyield(L, ud.func, ud.nresults);
 };
 
+const lua_type = function(L, idx) {
+    let o = index2addr(L, idx);
+    return o.ttnov(); // TODO: isvalid ? luaO_nilobject != nil tvalue ?
+};
+
+const lua_typename = function(L, t) {
+    assert(CT.LUA_TNONE <= t && t < CT.LUA_NUMTAGS, "invalid tag");
+    return ltm.ttypename(t);
+};
+
 
 /*
 ** 'load' and 'call' functions (run Lua code)
@@ -225,4 +244,7 @@ module.exports.lua_pushinteger = lua_pushinteger;
 module.exports.lua_pushlstring = lua_pushlstring;
 module.exports.lua_pushstring  = lua_pushstring;
 module.exports.lua_version     = lua_version;
-module.exports.lua_atpanic     = lua_atpanic;
\ No newline at end of file
+module.exports.lua_atpanic     = lua_atpanic;
+module.exports.lua_gettop      = lua_gettop;
+module.exports.lua_typename    = lua_typename;
+module.exports.lua_type        = lua_type;
\ No newline at end of file
diff --git a/src/lauxlib.js b/src/lauxlib.js
index 3ff346e..6cc3d3c 100644
--- a/src/lauxlib.js
+++ b/src/lauxlib.js
@@ -18,4 +18,10 @@ const luaL_newstate = function() {
 };
 
 
-module.exports.luaL_newstate = luaL_newstate;
\ No newline at end of file
+const luaL_typename = function(L, i) {
+    return lapi.lua_typename(L, lapi.lua_type(L, i));
+}
+
+
+module.exports.luaL_newstate = luaL_newstate;
+module.exports.luaL_typename = luaL_typename;
\ No newline at end of file
diff --git a/src/ltm.js b/src/ltm.js
index 8b4f4f5..77d65e4 100644
--- a/src/ltm.js
+++ b/src/ltm.js
@@ -40,6 +40,24 @@ const TMS = {
     TM_N:        26
 };
 
+const luaT_typenames_ = [
+    "no value",
+    "nil",
+    "boolean",
+    "userdata",
+    "number",
+    "string",
+    "table",
+    "function",
+    "userdata",
+    "thread",
+    "proto" /* this last case is used for tests only */
+];
+
+const ttypename = function(t) {
+    return luaT_typenames_[t + 1];
+};
+
 const luaT_init = function(L) {
     L.l_G.tmname = [];
     for (let event in TMS) {
@@ -112,4 +130,5 @@ module.exports.luaT_callbinTM   = luaT_callbinTM;
 module.exports.luaT_trybinTM    = luaT_trybinTM;
 module.exports.luaT_callorderTM = luaT_callorderTM;
 module.exports.luaT_gettmbyobj  = luaT_gettmbyobj;
-module.exports.luaT_init        = luaT_init;
\ No newline at end of file
+module.exports.luaT_init        = luaT_init;
+module.exports.ttypename        = ttypename;
\ No newline at end of file
diff --git a/tests/lapi.js b/tests/lapi.js
index b79c519..39477b2 100644
--- a/tests/lapi.js
+++ b/tests/lapi.js
@@ -1,31 +1,39 @@
 /*jshint esversion: 6 */
 "use strict";
 
-const test          = require('tape');
-const beautify      = require('js-beautify').js_beautify;
+const test     = require('tape');
+const beautify = require('js-beautify').js_beautify;
 
-const getState      = require("./tests.js").getState;
+const getState = require("./tests.js").getState;
 
-const VM            = require("../src/lvm.js");
-const ldo           = require("../src/ldo.js");
-const lapi          = require("../src/lapi.js");
-const lauxlib       = require("../src/lauxlib.js");
-const CT            = require('../src/lua.js').constant_types;
+const VM       = require("../src/lvm.js");
+const ldo      = require("../src/ldo.js");
+const lapi     = require("../src/lapi.js");
+const lauxlib  = require("../src/lauxlib.js");
+const CT       = require('../src/lua.js').constant_types;
 
-test('luaL_newstate, lua_pushnil', function (t) {
+test('luaL_newstate, lua_pushnil, lua_gettop, luaL_typename', function (t) {
     let L;
     
-    t.plan(2);
+    t.plan(3);
 
     t.doesNotThrow(function () {
-        L = lauxlib.luaL_newstate()
+
+        L = lauxlib.luaL_newstate();
 
         lapi.lua_pushnil(L);
+
     }, "JS Lua program ran without error");
 
     t.strictEqual(
-        L.stack[L.top - 1].type,
-        CT.LUA_TNIL,
-        "nil is on the stack"
+        lapi.lua_gettop(L),
+        1,
+        "top is correct"
+    );
+
+    t.strictEqual(
+        lauxlib.luaL_typename(L, lapi.lua_gettop(L)),
+        "nil",
+        "Correct element(s) on the stack"
     );
 });
\ No newline at end of file