table.move

3 files changed, 89 insertions, 22 deletions

diff --git a/src/lapi.js b/src/lapi.js
index f34216b..488fb58 100644
--- a/src/lapi.js
+++ b/src/lapi.js
@@ -538,6 +538,23 @@ const lua_topointer = function(L, idx) {
     }
 };
 
+const lua_compare = function(L, index1, index2, op) {
+    let i = 0;
+    let o1 = index2addr(L, index1);
+    let o2 = index2addr(L, index1);
+
+    if (!o1.ttisnil() && !o2.ttisnil()) {
+        switch (op) {
+            case lua.LUA_OPEQ: i = lvm.luaV_equalobj(L, o1, o2); break;
+            case lua.LUA_OPLT: i = lvm.luaV_lessthan(L, o1, o2); break;
+            case lua.LUA_OPLE: i = lvm.luaV_lessequal(L, o1, o2); break;
+            default: assert(false, "invalid option");
+        }
+    }
+
+    return i;
+};
+
 const lua_stringtonumber = function(L, s) {
     let number = parseFloat(s);
     L.stack[L.top++] = new TValue(number % 1 !== 0 ? CT.LUA_TNUMFLT : CT.LUA_TNUMINT, number);
@@ -568,6 +585,10 @@ const lua_typename = function(L, t) {
     return ltm.ttypename(t);
 };
 
+const lua_isnoneornil = function(L, n) {
+    return lua_type(L, n) <= 0;
+}
+
 const lua_istable = function(L, idx) {
     return index2addr(L, idx).ttistable();
 };
@@ -741,6 +762,7 @@ module.exports.lua_atpanic         = lua_atpanic;
 module.exports.lua_call            = lua_call;
 module.exports.lua_callk           = lua_callk;
 module.exports.lua_checkstack      = lua_checkstack;
+module.exports.lua_compare         = lua_compare;
 module.exports.lua_concat          = lua_concat;
 module.exports.lua_copy            = lua_copy;
 module.exports.lua_createtable     = lua_createtable;
@@ -755,6 +777,7 @@ module.exports.lua_getmetatable    = lua_getmetatable;
 module.exports.lua_gettable        = lua_gettable;
 module.exports.lua_gettop          = lua_gettop;
 module.exports.lua_insert          = lua_insert;
+module.exports.lua_isnoneornil     = lua_isnoneornil;
 module.exports.lua_isstring        = lua_isstring;
 module.exports.lua_istable         = lua_istable;
 module.exports.lua_len             = lua_len;
diff --git a/src/ltablib.js b/src/ltablib.js
index 6255761..97ecd65 100644
--- a/src/ltablib.js
+++ b/src/ltablib.js
@@ -9,6 +9,7 @@ const lauxlib = require('./lauxlib.js');
 const lstate  = require('./lstate.js');
 const ldo     = require('./ldo.js');
 const ldebug  = require('./ldebug.js');
+const llimit  = require('./llimit.js');
 const CT      = lua.constant_types;
 const TS      = lua.thread_status;
 
@@ -98,6 +99,41 @@ const tremove = function(L) {
     return 1;
 };
 
+/*
+** Copy elements (1[f], ..., 1[e]) into (tt[t], tt[t+1], ...). Whenever
+** possible, copy in increasing order, which is better for rehashing.
+** "possible" means destination after original range, or smaller
+** than origin, or copying to another table.
+*/
+const tmove = function(L) {
+    let f = lauxlib.luaL_checkinteger(L, 2);
+    let e = lauxlib.luaL_checkinteger(L, 3);
+    let t = lauxlib.luaL_checkinteger(L, 4);
+    let tt = !lapi.lua_isnoneornil(L, 5) ? 5 : 1;  /* destination table */
+    checktab(L, 1, TAB_R);
+    checktab(L, tt, TAB_W);
+    if (e >= f) {  /* otherwise, nothing to move */
+        lauxlib.luaL_argcheck(L, f > 0 || e < llimit.LUA_MAXINTEGER + f, 3, "too many elements to move");
+        let n = e - f + 1;  /* number of elements to move */
+        lauxlib.luaL_argcheck(L, t <= llimit.LUA_MAXINTEGER - n + 1, 4, "destination wrap around");
+
+        if (t > e || t <= f || (tt !== 1 && lapi.lua_compare(L, 1, tt, lua.LUA_OPEQ) !== 1)) {
+            for (let i = 0; i < n; i++) {
+                lapi.lua_geti(L, 1, f + i);
+                lapi.lua_seti(L, tt, t + i);
+            }
+        } else {
+            for (let i = n - 1; i >= 0; i--) {
+                lapi.lua_geti(L, 1, f + i);
+                lapi.lua_seti(L, tt, t + i);
+            }
+        }
+    }
+
+    lapi.lua_pushvalue(L, tt);  /* return destination table */
+    return 1;
+};
+
 const tconcat = function(L) {
     let last = aux_getn(L, 1, TAB_R);
     let sep = lauxlib.luaL_optlstring(L, 2, "");
@@ -147,6 +183,7 @@ const unpack = function(L) {
 const tab_funcs = {
     "concat": tconcat,
     "insert": tinsert,
+    "move":   tmove,
     "pack":   pack,
     "remove": tremove,
     "unpack": unpack
diff --git a/src/lua.js b/src/lua.js
index 358be64..c7d1fd7 100644
--- a/src/lua.js
+++ b/src/lua.js
@@ -62,6 +62,10 @@ constant_types.LUA_TLCL = constant_types.LUA_TFUNCTION | (0 << 4);  /* Lua closu
 constant_types.LUA_TLCF = constant_types.LUA_TFUNCTION | (1 << 4);  /* light C function */
 constant_types.LUA_TCCL = constant_types.LUA_TFUNCTION | (2 << 4);  /* C closure */
 
+const LUA_OPEQ = 0;
+const LUA_OPLT = 1;
+const LUA_OPLE = 2;
+
 const LUA_NUMTAGS = 9;
 const LUA_MINSTACK = 20;
 
@@ -102,33 +106,36 @@ class lua_Debug {
 
 }
 
-module.exports.lua_Debug               = lua_Debug;
-module.exports.constant_types          = constant_types;
-module.exports.thread_status           = thread_status;
-module.exports.LUA_MULTRET             = -1;
-module.exports.print_version           = print_version;
-module.exports.LUA_VERSION_MAJOR       = LUA_VERSION_MAJOR;
-module.exports.LUA_VERSION_MINOR       = LUA_VERSION_MINOR;
-module.exports.LUA_VERSION_NUM         = LUA_VERSION_NUM;
-module.exports.LUA_VERSION_RELEASE     = LUA_VERSION_RELEASE;
-module.exports.LUA_VERSION             = LUA_VERSION;
-module.exports.LUA_RELEASE             = LUA_RELEASE;
-module.exports.LUA_COPYRIGHT           = LUA_COPYRIGHT;
-module.exports.LUA_AUTHORS             = LUA_AUTHORS;
+module.exports.FENGARI_AUTHORS         = FENGARI_AUTHORS;
+module.exports.FENGARI_COPYRIGHT       = FENGARI_COPYRIGHT;
+module.exports.FENGARI_RELEASE         = FENGARI_RELEASE;
+module.exports.FENGARI_VERSION         = FENGARI_VERSION;
 module.exports.FENGARI_VERSION_MAJOR   = FENGARI_VERSION_MAJOR;
 module.exports.FENGARI_VERSION_MINOR   = FENGARI_VERSION_MINOR;
 module.exports.FENGARI_VERSION_NUM     = FENGARI_VERSION_NUM;
 module.exports.FENGARI_VERSION_RELEASE = FENGARI_VERSION_RELEASE;
-module.exports.FENGARI_VERSION         = FENGARI_VERSION;
-module.exports.FENGARI_RELEASE         = FENGARI_RELEASE;
-module.exports.FENGARI_COPYRIGHT       = FENGARI_COPYRIGHT;
-module.exports.FENGARI_AUTHORS         = FENGARI_AUTHORS;
-module.exports.LUA_INIT_VAR            = LUA_INIT_VAR;
+module.exports.LUA_AUTHORS             = LUA_AUTHORS;
+module.exports.LUA_COPYRIGHT           = LUA_COPYRIGHT;
 module.exports.LUA_INITVARVERSION      = LUA_INITVARVERSION;
-module.exports.LUA_NUMTAGS             = LUA_NUMTAGS;
+module.exports.LUA_INIT_VAR            = LUA_INIT_VAR;
 module.exports.LUA_MINSTACK            = LUA_MINSTACK;
-module.exports.LUA_RIDX_MAINTHREAD     = LUA_RIDX_MAINTHREAD;
+module.exports.LUA_MULTRET             = -1;
+module.exports.LUA_NUMTAGS             = LUA_NUMTAGS;
+module.exports.LUA_OPEQ                = LUA_OPEQ;
+module.exports.LUA_OPLE                = LUA_OPLE;
+module.exports.LUA_OPLT                = LUA_OPLT;
+module.exports.LUA_REGISTRYINDEX       = LUA_REGISTRYINDEX;
+module.exports.LUA_RELEASE             = LUA_RELEASE;
 module.exports.LUA_RIDX_GLOBALS        = LUA_RIDX_GLOBALS;
 module.exports.LUA_RIDX_LAST           = LUA_RIDX_LAST;
-module.exports.LUA_REGISTRYINDEX       = LUA_REGISTRYINDEX;
-module.exports.lua_upvalueindex        = lua_upvalueindex;
\ No newline at end of file
+module.exports.LUA_RIDX_MAINTHREAD     = LUA_RIDX_MAINTHREAD;
+module.exports.LUA_VERSION             = LUA_VERSION;
+module.exports.LUA_VERSION_MAJOR       = LUA_VERSION_MAJOR;
+module.exports.LUA_VERSION_MINOR       = LUA_VERSION_MINOR;
+module.exports.LUA_VERSION_NUM         = LUA_VERSION_NUM;
+module.exports.LUA_VERSION_RELEASE     = LUA_VERSION_RELEASE;
+module.exports.constant_types          = constant_types;
+module.exports.lua_Debug               = lua_Debug;
+module.exports.lua_upvalueindex        = lua_upvalueindex;
+module.exports.print_version           = print_version;
+module.exports.thread_status           = thread_status;
\ No newline at end of file