Improve calling convention handling when the number of arguments doesn't match the expected number, and the number of return values doesn't match those needed.

src/main/java/lua/Builtin.java

@@ -4,6 +4,7 @@
 package lua;
 
 import lua.value.LFunction;
+import lua.value.LNil;
 import lua.value.LString;
 import lua.value.LTable;
 import lua.value.LValue;
@@ -30,7 +31,7 @@ final class Builtin extends LFunction {
 	}
 	
 	// perform a lua call
-	public void luaStackCall(StackState state, int base, int nargs) {
+	public int luaStackCall(StackState state, int base, int nargs) {
 		switch ( id ) {
 		case PRINT:
 			for ( int i=0; i<nargs; i++ ) {
@@ -39,13 +40,14 @@ final class Builtin extends LFunction {
 				System.out.print( String.valueOf(state.stack[base+1+i]) );
 			}
 			System.out.println();
-			return;
+			return 0;
 		case PAIRS:
 			LValue value = state.stack[base+1].luaPairs();
 			state.stack[base] = value;
-			return;
+			return 1;
 		default:
 			luaUnsupportedOperation();
+			return 0;
 		}
 	}
 

src/main/java/lua/io/Closure.java

@@ -17,7 +17,8 @@ public class Closure extends LValue {
 
 
 	// perform a lua call
-	public void luaStackCall(StackState state, int base, int nresults) {
-		state.vmExecute( this, base+1 );
+	public int luaStackCall(StackState state, int base, int nargs) {
+		state.clear( base+1+nargs, p.numparams-nargs );
+		return state.vmExecute( this, base+1 );
 	}
 }

src/main/java/lua/value/LTable.java

@@ -50,15 +50,14 @@ public class LTable extends LValue {
 		}
 
 		// perform a lua call
-		public void luaStackCall(StackState state, int base, int nresults) {
+		public int luaStackCall(StackState state, int base, int nargs) {
 			if ( e.hasMoreElements() ) {
 				LValue key = (LValue) e.nextElement();
 				state.stack[base] = key;
 				state.stack[base+1] = t.luaGetTable(key);
-			} else {
-				state.stack[base] = LNil.NIL;
+				return 2;
 			}
-			
+			return 0;			
 		}
 	}
 

src/main/java/lua/value/LValue.java

@@ -14,9 +14,10 @@ public class LValue {
 		return true;
 	}
 
-	// perform a lua call
-	public void luaStackCall(StackState state, int base, int nargs) {
+	// perform a lua call, return number of results actually produced
+	public int luaStackCall(StackState state, int base, int nargs) {
 		luaUnsupportedOperation();
+		return 0;
 	}
 
 	// unsupported except for numbers

src/test/res/compile.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 LUA_HOME=/cygdrive/c/programs/lua5.1
 TESTS="test1 test2 test3 test4 test5"
-#TESTS="test5"
+TESTS="test3"
 for x in $TESTS
 do
     echo compiling $x

src/test/res/test3.lua

@@ -1,6 +1,40 @@
-a = func(1, 2, 3)
-a = func(3, 2, 1)
-a = func(func(),func(),func())
+function f0() print( "f0:" ) end
+function f1(a) print( "f1:", a ) end
+function f2(a,b) print( "f2:", a, b ) end
+function f3(a,b,c) print( "f3:", a, b, c ) end
+function f4(a,b,c,d) print( "f4:", a, b, c, d ) end
 
+f0()  f0( "a1/1" ) f0( "a1/2", "a2/2" ) f0( "a1/3", "a2/3", "a3/3" ) f0( "a1/4", "a2/4", "a3/4", "a4/4" )
+f1()  f1( "a1/1" ) f1( "a1/2", "a2/2" ) f1( "a1/3", "a2/3", "a3/3" ) f1( "a1/4", "a2/4", "a3/4", "a4/4" )
+f2()  f2( "a1/1" ) f2( "a1/2", "a2/2" ) f2( "a1/3", "a2/3", "a3/3" ) f2( "a1/4", "a2/4", "a3/4", "a4/4" )
+f3()  f3( "a1/1" ) f3( "a1/2", "a2/2" ) f3( "a1/3", "a2/3", "a3/3" ) f3( "a1/4", "a2/4", "a3/4", "a4/4" )
+f4()  f4( "a1/1" ) f4( "a1/2", "a2/2" ) f4( "a1/3", "a2/3", "a3/3" ) f4( "a1/4", "a2/4", "a3/4", "a4/4" )
 
+function g0(a,b,c,d) return end
+function g1(a,b,c,d) return d end
+function g2(a,b,c,d) return c, d end
+function g3(a,b,c,d) return b, c, d end
+function g4(a,b,c,d) return a, b, c, d end
+
+z = g0("c0.1/4", "c0.2/4", "c0.3/4", "c0.4/4")
+print( "z0:", z )
+z = g2("c2.1/4", "c2.2/4", "c2.3/4", "c2.4/4")
+print( "z2:", z )
+z = g4("c4.1/4", "c4.2/4", "c4.3/4", "c4.4/4")
+print( "z4:", z )
+
+a,b,c,d = g0( "c0.1/4", "c0.2/4", "c0.3/4", "c0.4/4" )
+print( "g0:", a, b, c, d, "(eol" )
+a,b,c,d = g2( "b2.1/4", "b2.2/4", "b2.3/4", "b2.4/4" )
+print( "g2:", a, b, c, d, "(eol)" )
+a,b,c,d = g4( "b4.1/4", "b4.2/4", "b4.3/4", "b4.4/4" )
+print( "g4:", a, b, c, d, "(eol)" )
+
+function func(a,b,c)
+	return a, b, c
+end
+
+print( func(11, 12, 13) )
+print( func(23, 22, 21) )
+print( func(func(32,33,34), func(45,46,47), func(58,59,50)) )