table.concat

7 files changed, 232 insertions, 27 deletions

diff --git a/src/lapi.js b/src/lapi.js
index c841ba2..6316326 100644
--- a/src/lapi.js
+++ b/src/lapi.js
@@ -205,7 +205,7 @@ const lua_pushinteger = function(L, n) {
 
 const lua_pushlstring = function(L, s, len) { // TODO: embedded \0
     assert(typeof s === "string");
-    assert(typeof n === "number");
+    assert(typeof len === "number");
 
     let ts = len === 0 ? new TValue(CT.LUA_TLNGSTR, "") : new TValue(CT.LUA_TLNGSTR, s.substr(0, len));
     L.stack[L.top++] = ts;
@@ -538,6 +538,15 @@ const lua_stringtonumber = function(L, s) {
     return s.length;
 };
 
+// TODO: pisnum
+const lua_tointegerx = function(L, idx) {
+    let o = index2addr(L, idx);
+    let res = lvm.tointeger(o);
+    if (res === false)
+        res = 0;  /* call to 'tointeger' may change 'n' even if it fails */
+    return res;
+};
+
 const f_call = function(L, ud) {
     ldo.luaD_callnoyield(L, ud.funcOff, ud.nresults);
 };
@@ -701,6 +710,12 @@ const lua_concat = function(L, n) {
     }
 };
 
+const lua_len = function(L, idx) {
+    let t = index2addr(L, idx);
+    lvm.luaV_objlen(L, L.top++, t);
+    assert(L.top <= L.ci.top, "stack overflow");
+};
+
 // This functions are only there for compatibility purposes
 const lua_gc = function () {};
 
@@ -735,6 +750,7 @@ module.exports.lua_gettop          = lua_gettop;
 module.exports.lua_insert          = lua_insert;
 module.exports.lua_isstring        = lua_isstring;
 module.exports.lua_istable         = lua_istable;
+module.exports.lua_len             = lua_len;
 module.exports.lua_load            = lua_load;
 module.exports.lua_newtable        = lua_newtable;
 module.exports.lua_next            = lua_next;
@@ -771,6 +787,7 @@ module.exports.lua_status          = lua_status;
 module.exports.lua_stringtonumber  = lua_stringtonumber;
 module.exports.lua_toboolean       = lua_toboolean;
 module.exports.lua_tointeger       = lua_tointeger;
+module.exports.lua_tointegerx      = lua_tointegerx;
 module.exports.lua_tolstring       = lua_tolstring;
 module.exports.lua_tonumber        = lua_tonumber;
 module.exports.lua_topointer       = lua_topointer;
diff --git a/src/lauxlib.js b/src/lauxlib.js
index a04f3be..ba720af 100644
--- a/src/lauxlib.js
+++ b/src/lauxlib.js
@@ -9,9 +9,16 @@ const lua    = require('./lua.js');
 const ldebug = require('./ldebug.js');
 const CT     = lua.constant_types;
 
-const LUA_LOADED_TABLE = "_LOADED"
+const LUA_LOADED_TABLE = "_LOADED";
 
 
+class luaL_Buffer {
+    constructor(L) {
+        this.L = L;
+        this.b = "";
+    }
+}
+
 /*
 ** search for 'objidx' in table at index -1.
 ** return 1 + string at top if find a good name.
@@ -95,7 +102,7 @@ const typeerror = function(L, arg, tname) {
     else
         typearg = luaL_typename(L, arg);
 
-    let msg = lua_pushstring(L, `${tname} expected, got ${typearg}`);
+    let msg = lapi.lua_pushstring(L, `${tname} expected, got ${typearg}`);
     return luaL_argerror(L, arg, msg);
 };
 
@@ -183,6 +190,30 @@ const luaL_optinteger = function(L, arg, def) {
     return luaL_opt(L, luaL_checkinteger, arg, def);
 };
 
+const luaL_buffinit = function(L, B) {
+    B.L = L;
+    B.b = "";
+};
+
+const luaL_addlstring = function(B, s) {
+    B.b += s;
+};
+
+const luaL_addstring = luaL_addlstring;
+
+const luaL_pushresult = function(B) {
+    let L = B.L;
+    lapi.lua_pushstring(L, B.b);
+};
+
+const luaL_addvalue = function(B) {
+    let L = B.L;
+    let s = lapi.lua_tostring(L, -1);
+    // TODO: buffonstack ? necessary ?
+    luaL_addstring(B, s);
+    lapi.lua_remove(L, -1);
+};
+
 const luaL_opt = function(L, f, n, d) {
     return lapi.lua_type(L, n) <= 0 ? d : f(L, n);
 };
@@ -210,6 +241,15 @@ const luaL_callmeta = function(L, obj, event) {
     return true;
 };
 
+const luaL_len = function(L, idx) {
+    lapi.lua_len(L, idx);
+    let l = lapi.lua_tointegerx(L, -1);
+    if (l === false)
+        luaL_error(L, "object length is not an integer");
+    lapi.lua_pop(L, 1);  /* remove object */
+    return l;
+};
+
 const luaL_tolstring = function(L, idx) {
     if (luaL_callmeta(L, idx, "__tostring")) {
         if (!lapi.lua_isstring(L, -1))
@@ -226,7 +266,7 @@ const luaL_tolstring = function(L, idx) {
                 break;
             default:
                 let tt = luaL_getmetafield(L, idx, "__name");
-                let kind = tt === CT.LUA_TSTRING ? lua_tostring(L, -1) : luaL_typename(L, idx);
+                let kind = tt === CT.LUA_TSTRING ? lapi.lua_tostring(L, -1) : luaL_typename(L, idx);
                 lapi.lua_pushstring(L, `${kind}`); // We can't print memory address in JS
                 if (tt !== CT.LUA_TNIL)
                     lapi.lua_remove(L, -2);
@@ -315,26 +355,33 @@ const luaL_newlib = function(L, l) {
     luaL_setfuncs(L, l, 0);
 };
 
-module.exports.luaL_newstate     = luaL_newstate;
-module.exports.luaL_typename     = luaL_typename;
+module.exports.LUA_LOADED_TABLE  = LUA_LOADED_TABLE;
+module.exports.luaL_addlstring   = luaL_addlstring;
+module.exports.luaL_addstring    = luaL_addstring;
+module.exports.luaL_addvalue     = luaL_addvalue;
+module.exports.luaL_argcheck     = luaL_argcheck;
+module.exports.luaL_argerror     = luaL_argerror;
+module.exports.luaL_Buffer       = luaL_Buffer;
+module.exports.luaL_buffinit     = luaL_buffinit;
+module.exports.luaL_callmeta     = luaL_callmeta;
 module.exports.luaL_checkany     = luaL_checkany;
+module.exports.luaL_checkinteger = luaL_checkinteger;
+module.exports.luaL_checklstring = luaL_checklstring;
+module.exports.luaL_checkstack   = luaL_checkstack;
 module.exports.luaL_checktype    = luaL_checktype;
-module.exports.luaL_callmeta     = luaL_callmeta;
+module.exports.luaL_error        = luaL_error;
 module.exports.luaL_getmetafield = luaL_getmetafield;
-module.exports.luaL_requiref     = luaL_requiref;
 module.exports.luaL_getsubtable  = luaL_getsubtable;
-module.exports.luaL_setfuncs     = luaL_setfuncs;
-module.exports.luaL_checkstack   = luaL_checkstack;
-module.exports.LUA_LOADED_TABLE  = LUA_LOADED_TABLE;
-module.exports.luaL_tolstring    = luaL_tolstring;
-module.exports.luaL_argcheck     = luaL_argcheck;
-module.exports.luaL_checklstring = luaL_checklstring;
+module.exports.luaL_len          = luaL_len;
+module.exports.luaL_newlib       = luaL_newlib;
+module.exports.luaL_newstate     = luaL_newstate;
+module.exports.luaL_opt          = luaL_opt;
+module.exports.luaL_optinteger   = luaL_optinteger;
 module.exports.luaL_optlstring   = luaL_optlstring;
 module.exports.luaL_optstring    = luaL_optstring;
-module.exports.luaL_checkinteger = luaL_checkinteger;
-module.exports.luaL_optinteger   = luaL_optinteger;
-module.exports.luaL_opt          = luaL_opt;
-module.exports.luaL_where        = luaL_where;
-module.exports.luaL_error        = luaL_error;
-module.exports.luaL_argerror     = luaL_argerror;
-module.exports.luaL_newlib       = luaL_newlib;
\ No newline at end of file
+module.exports.luaL_pushresult   = luaL_pushresult;
+module.exports.luaL_requiref     = luaL_requiref;
+module.exports.luaL_setfuncs     = luaL_setfuncs;
+module.exports.luaL_tolstring    = luaL_tolstring;
+module.exports.luaL_typename     = luaL_typename;
+module.exports.luaL_where        = luaL_where;
\ No newline at end of file
diff --git a/src/linit.js b/src/linit.js
index d52b640..eb8caf2 100644
--- a/src/linit.js
+++ b/src/linit.js
@@ -8,10 +8,12 @@ const lauxlib  = require('./lauxlib.js');
 const lualib   = require('./lualib.js');
 const lbaselib = require('./lbaselib.js');
 const lcorolib = require('./lcorolib.js');
+const ltablib  = require('./ltablib.js');
 
 const loadedlibs = {
-    [lualib.LUA_COLIBNAME]: lcorolib.luaopen_coroutine,
-    "_G":                  lbaselib.luaopen_base
+    [lualib.LUA_TABLIBNAME]: ltablib.luaopen_table,
+    [lualib.LUA_COLIBNAME]:  lcorolib.luaopen_coroutine,
+    "_G":                    lbaselib.luaopen_base
 };
 
 const luaL_openlibs = function(L) {
diff --git a/src/ltablib.js b/src/ltablib.js
new file mode 100644
index 0000000..8e1f758
--- /dev/null
+++ b/src/ltablib.js
@@ -0,0 +1,92 @@
+/* jshint esversion: 6 */
+"use strict";
+
+const assert  = require('assert');
+
+const lua     = require('./lua.js');
+const lapi    = require('./lapi.js');
+const lauxlib = require('./lauxlib.js');
+const lstate  = require('./lstate.js');
+const ldo     = require('./ldo.js');
+const ldebug  = require('./ldebug.js');
+const CT      = lua.constant_types;
+const TS      = lua.thread_status;
+
+
+/*
+** Operations that an object must define to mimic a table
+** (some functions only need some of them)
+*/
+const TAB_R  = 1;               /* read */
+const TAB_W  = 2;               /* write */
+const TAB_L  = 4;               /* length */
+const TAB_RW = (TAB_R | TAB_W); /* read/write */
+
+const checkfield = function(L, key, n) {
+    lapi.lua_pushstring(L, key);
+    return lapi.lua_rawget(L, -n) !== CT.LUA_TNIL;
+};
+
+/*
+** Check that 'arg' either is a table or can behave like one (that is,
+** has a metatable with the required metamethods)
+*/
+const checktab = function(L, arg, what) {
+    if (lapi.lua_type(L, arg) !== CT.LUA_TTABLE) {  /* is it not a table? */
+        let n = 1;
+        if (lapi.lua_getmetatable(L, arg) &&  /* must have metatable */
+            (!(what & TAB_R) || checkfield(L, "__index", ++n)) &&
+            (!(what & TAB_W) || checkfield(L, "__newindex", ++n)) &&
+            (!(what & TAB_L) || checkfield(L, "__len", ++n))) {
+            lapi.lua_pop(L, n);  /* pop metatable and tested metamethods */
+        }
+        else
+            lauxlib.luaL_checktype(L, arg, CT.LUA_TTABLE);  /* force an error */
+    }
+};
+
+const aux_getn = function(L, n, w) {
+    checktab(L, n, w | TAB_L);
+    lauxlib.luaL_len(L, n);
+};
+
+const addfield = function(L, b, i) {
+    lapi.lua_geti(L, 1, i);
+    if (!lapi.lua_isstring(L, -1))
+        lauxlib.luaL_error(L, `invalid value (${lauxlib.luaL_typename(L, -1)}) at index ${i} in table for 'concat'`);
+
+    lauxlib.luaL_addvalue(b);
+};
+
+const tconcat = function(L) {
+    let last = aux_getn(L, 1, TAB_R);
+    let sep = lauxlib.luaL_optlstring(L, 2, "");
+    let i = lauxlib.luaL_optinteger(L, 3, 1);
+    last = lauxlib.luaL_optinteger(L, 4, last);
+
+    let b = new lauxlib.luaL_Buffer();
+    lauxlib.luaL_buffinit(L, b);
+
+    for (; i < last; i++) {
+        addfield(L, b, i);
+        lauxlib.luaL_addlstring(b, sep);
+    }
+
+    if (i === last)
+        addfield(L, b, i);
+
+    lauxlib.luaL_pushresult(b);
+
+    return 1;
+};
+
+const tab_funcs = {
+    "concat": tconcat
+};
+
+const luaopen_table = function(L) {
+    lauxlib.luaL_newlib(L, tab_funcs);
+    return 1;
+};
+
+module.exports.luaopen_table = luaopen_table;
\ No newline at end of file
diff --git a/src/lvm.js b/src/lvm.js
index 95e8cc4..16a3bd2 100644
--- a/src/lvm.js
+++ b/src/lvm.js
@@ -915,7 +915,7 @@ const luaV_objlen = function(L, ra, rb) {
         case CT.LUA_TTABLE: {
             tm = ltm.luaT_gettmbyobj(L, rb, ltm.TMS.TM_LEN);
             if (!tm.ttisnil()) break;
-            L.stack[ra] = rb.luaH_getn();
+            L.stack[ra] = new TValue(CT.LUA_TNUMINT, rb.luaH_getn());
             return;
         }
         case CT.LUA_TSHRSTR:
diff --git a/tests/ltablib.js b/tests/ltablib.js
new file mode 100644
index 0000000..22a6797
--- /dev/null
+++ b/tests/ltablib.js
@@ -0,0 +1,47 @@
+/*jshint esversion: 6 */
+"use strict";
+
+const test       = require('tape');
+const beautify   = require('js-beautify').js_beautify;
+
+const tests      = require("./tests.js");
+const getState   = tests.getState;
+const toByteCode = tests.toByteCode;
+
+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 lua        = require('../src/lua.js');
+const linit      = require('../src/linit.js');
+const lstate     = require('../src/lstate.js');
+const CT         = lua.constant_types;
+
+
+test('table.concat', function (t) {
+    let luaCode = `
+        return table.concat({1, 2, 3, 4, 5, 6, 7}, ",", 3, 5)
+    `, L;
+    
+    t.plan(2);
+
+    t.doesNotThrow(function () {
+
+        let bc = toByteCode(luaCode).dataView;
+
+        L = lauxlib.luaL_newstate();
+
+        linit.luaL_openlibs(L);
+
+        lapi.lua_load(L, bc, "test-table.concat");
+
+        lapi.lua_call(L, 0, -1);
+
+    }, "JS Lua program ran without error");
+
+    t.strictEqual(
+        lapi.lua_tostring(L, -1),
+        "3,4,5",
+        "Correct element(s) on the stack"
+    );
+});
\ No newline at end of file
diff --git a/tests/lvm.js b/tests/lvm.js
index 8517393..4f02ed5 100644
--- a/tests/lvm.js
+++ b/tests/lvm.js
@@ -758,19 +758,19 @@ test('LEN', function (t) {
     }, "Program executed without errors");
 
     t.strictEqual(
-        L.stack[L.top - 1],
+        L.stack[L.top - 1].value,
         5,
         "Program output is correct"
     );
 
     t.strictEqual(
-        L.stack[L.top - 2],
+        L.stack[L.top - 2].value,
         3,
         "Program output is correct"
     );
 
     t.strictEqual(
-        L.stack[L.top - 3],
+        L.stack[L.top - 3].value,
         0,
         "Program output is correct"
     );