From b618b835c74a8637e00ba1f4adf6b8884d360d43 Mon Sep 17 00:00:00 2001
From: Benoit Giannangeli <benoit.giannangeli@boursorama.fr>
Date: Fri, 3 Feb 2017 15:59:29 +0100
Subject: Table, metatable

---
 luac.out       | Bin 241 -> 190 bytes
 src/lobject.js |  64 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 src/lvm.js     |   2 ++
 tests/lvm.js   |  23 +++++++++++++++++++++
 4 files changed, 88 insertions(+), 1 deletion(-)

diff --git a/luac.out b/luac.out
index 85aec6d..0b992bf 100644
Binary files a/luac.out and b/luac.out differ
diff --git a/src/lobject.js b/src/lobject.js
index 7efbef5..876a16f 100644
--- a/src/lobject.js
+++ b/src/lobject.js
@@ -18,11 +18,73 @@ class TValue {
     constructor(type, value) {
         this.type = type;
         this.value = value;
+        this.metatable = null;
     }
 
 }
 
+
+class TString extends TValue {
+
+    constructor(string) {
+        super(CT.LUA_TSTRING, string);
+    }
+
+}
+
+
+class Table extends TValue {
+
+    constructor(array, hash) {
+        super(CT.LUA_TTABLE, {
+            array: array !== undefined ? array : [],
+            hash: new Map(hash)
+        });
+
+        this.usermetatable = null;
+
+        this.metatable = {
+            __newindex: function (table, key) {
+                if (key instanceof TValue) {
+                    // Those lua values are used by value, tables and functions by reference
+                    if ([CT.TNUMBER, CT.TSTRING, CT.TSHRSTR, CT.TLNGSTR, CT.TNUMFLT, CT.TNUMINT].indexOf(key.type) > -1) {
+                        key = key.value;
+                    }
+                }
+
+                if (typeof key === 'number') {
+                    table.value.array[key] = value;
+                } else {
+                    table.value.hash.set(key, value);
+                }
+            },
+
+            __index: function (table, key, value) {
+                if (key instanceof TValue) {
+                    // Those lua values are used by value, tables and functions by reference
+                    if ([CT.TNUMBER, CT.TSTRING, CT.TSHRSTR, CT.TLNGSTR, CT.TNUMFLT, CT.TNUMINT].indexOf(key.type) > -1) {
+                        key = key.value;
+                    }
+                }
+
+                if (typeof key === 'number') {
+                    return table.value.array[key];
+                } else {
+                    return table.value.hash.get(key);
+                }
+            },
+
+            __len: function (table) {
+                return t.value.array.length;
+            }
+        };
+    }
+
+}
+
+
 module.exports = {
     LClosure: LClosure,
-    TValue: TValue
+    TValue: TValue,
+    Table: Table
 };
\ No newline at end of file
diff --git a/src/lvm.js b/src/lvm.js
index 3d6f43a..9518721 100644
--- a/src/lvm.js
+++ b/src/lvm.js
@@ -5,6 +5,7 @@ const BytecodeParser = require("./lundump.js");
 const OC             = require('./lopcodes.js');
 const CT             = require('./lua.js').constant_types;
 const TValue         = require('./lobject.js').TValue;
+const Table          = require('./lobject.js').Table;
 
 class LuaVM {
 
@@ -104,6 +105,7 @@ class LuaVM {
                     break;
                 }
                 case "OP_NEWTABLE": {
+                    L.stack[ra] = new Table();
                     break;
                 }
                 case "OP_SELF": {
diff --git a/tests/lvm.js b/tests/lvm.js
index 6a4ed9f..1dbff2e 100644
--- a/tests/lvm.js
+++ b/tests/lvm.js
@@ -10,6 +10,7 @@ const DataView       = require('buffer-dataview');
 const BytecodeParser = require("../src/lundump.js");
 const lua_State      = require("../src/lstate.js").lua_State;
 const LuaVM          = require("../src/lvm.js").LuaVM;
+const Table          = require("../src/lobject.js").Table;
 
 const toByteCode = function (luaCode) {
     var luaFile = tmp.fileSync(),
@@ -134,4 +135,26 @@ test('Unary op, LOADBOOL', function (t) {
         [-5, true, -6],
         "Program output is correct"
     );
+});
+
+
+test('NEWTABLE', function (t) {
+    let luaCode = `
+        local a = {}
+        return a
+    `, vm;
+    
+    t.plan(2);
+
+    t.comment("Running following code: \n" + luaCode);
+
+    t.doesNotThrow(function () {
+        vm = getVM(luaCode);
+        vm.execute();
+    }, "Program executed without errors");
+
+    t.ok(
+        vm.L.stack[0] instanceof Table,
+        "Program output is correct"
+    );
 });
\ No newline at end of file
-- 
cgit v1.2.3-70-g09d2