Add metatag test.

src/core/org/luaj/vm2/LuaValue.java

@@ -216,7 +216,7 @@ public class LuaValue extends Varargs {
 	public LuaValue call() { return callmt().call(this); }
 	public LuaValue call(LuaValue arg) { return callmt().call(this,arg); }
 	public LuaValue call(LuaValue arg1, LuaValue arg2) { return callmt().call(this,arg1,arg2); }
-	public LuaValue call(LuaValue arg1, LuaValue arg2, LuaValue arg3) { return callmt().invoke(LuaValue.varargsOf(new LuaValue[]{this,arg1,arg2,arg3})).arg1(); }
+	public LuaValue call(LuaValue arg1, LuaValue arg2, LuaValue arg3) { return callmt().invoke(new LuaValue[]{this,arg1,arg2,arg3}).arg1(); }
 	public LuaValue method(String name) { return this.get(name).call(this); }
 	public LuaValue method(LuaValue name) { return this.get(name).call(this); }
 	public LuaValue method(String name, LuaValue arg) { return this.get(name).call(this,arg); }
@@ -224,7 +224,7 @@ public class LuaValue extends Varargs {
 	public LuaValue method(String name, LuaValue arg1, LuaValue arg2) { return this.get(name).call(this,arg1,arg2); }
 	public LuaValue method(LuaValue name, LuaValue arg1, LuaValue arg2) { return this.get(name).call(this,arg1,arg2); }
 	public Varargs invoke() { return invoke(NONE); }
-	public Varargs invoke(Varargs args) { return callmt().invoke(args); }
+	public Varargs invoke(Varargs args) { return callmt().invoke(this,args); }
 	public Varargs invoke(LuaValue arg,Varargs varargs) { return invoke(varargsOf(arg,varargs)); }
 	public Varargs invoke(LuaValue arg1,LuaValue arg2,Varargs varargs) { return invoke(varargsOf(arg1,arg2,varargs)); }
 	public Varargs invoke(LuaValue[] args) { return invoke(varargsOf(args)); }

src/core/org/luaj/vm2/lib/DebugLib.java

@@ -557,6 +557,7 @@ public class DebugLib extends VarArgFunction {
 				case TBOOLEAN:  LuaBoolean.s_metatable  = mt; break;
 				case TSTRING:   LuaString.s_metatable   = mt; break;
 				case TFUNCTION: LuaFunction.s_metatable = mt; break;
+				case TTHREAD:   LuaThread.s_metatable   = mt; break;
 				default: object.setmetatable( mt );
 			}
 			return LuaValue.TRUE;

test/junit/org/luaj/vm2/CompatibiltyTest.java

@@ -49,6 +49,7 @@ public class CompatibiltyTest extends TestSuite {
 		public void testIoLib()         { runTest("iolib");     }
 		public void testManyUpvals()    { runTest("manyupvals"); }
 		public void testMathLib()       { runTest("mathlib"); }
+		public void testMetatags()      { runTest("metatags"); }
 		public void testOsLib()         { runTest("oslib"); }
 		public void testStringLib()     { runTest("stringlib"); }
 		public void testTableLib()      { runTest("tablelib"); }

test/lua/metatags.lua

@@ -0,0 +1,39 @@
+print( '---- initial metatables' )
+local values = { 1, false, coroutine.create( function() end ) }
+for i=1,#values do
+	print( debug.getmetatable( values[i] ) )
+end
+
+local mt = {
+	__call=function(a,b,c) 
+		print( 'mt.__call()', type(a), type(b), type(c), b, c )
+		return '__call-result'
+	end,
+}
+
+-- pcall a function and check for a pattern in the error string
+ecall = function(pattern, ...)
+	local s,e = pcall(...)
+	if not s then e = string.match(e,pattern) or e end
+	return s,e
+end 
+
+print( '---- __call' )
+for i=1,#values do
+	print( type(values[i]), 'before', ecall( 'attempt to call', function() return values[i]('a','b') end ) )
+	print( debug.setmetatable( values[i], mt ) )
+	print( type(values[i]), 'after', pcall( function() return values[i]() end ) )
+	print( type(values[i]), 'after', pcall( function() return values[i]('a') end ) )
+	print( type(values[i]), 'after', pcall( function() return values[i]('a','b') end ) )
+	print( type(values[i]), 'after', pcall( function() return values[i]('a','b','c') end ) )
+	print( type(values[i]), 'after', pcall( function() return values[i]('a','b','c','d') end ) )
+	print( debug.setmetatable( values[i], nil ) )
+end
+
+
+
+print( '---- final metatables' )
+for i=1,#values do 
+	print( debug.getmetatable( values[i] ) )
+end
+