Add noarg parse, multi write test

go/asm/asm.go

@@ -294,6 +294,24 @@ func parseSized(op vm.Opcode, arg Arg, w io.Writer) (int, error) {
 	return rn, err
 }
 
+func parseNoarg(op vm.Opcode, arg Arg, w io.Writer) (int, error) {
+	var rn int
+
+	b := bytes.NewBuffer(nil)
+
+	n, err := writeOpcode(op, b)
+	rn += n
+	if  err != nil {
+		return rn, err
+	}
+	if w != nil {
+		rn, err = w.Write(b.Bytes())
+	} else {
+		rn = 0
+	}
+	return rn, err
+}
+
 func Parse(s string, w io.Writer) (int, error) {
 	rd := strings.NewReader(s)
 	ast, err := asmParser.Parse("file", rd)
@@ -334,6 +352,15 @@ func Parse(s string, w io.Writer) (int, error) {
 			rn += n
 			continue
 		}
+		n, err = parseNoarg(op, v.OpArg, w)
+		if err != nil {
+			return n, err
+		}
+		if n > 0 {
+			rn += n
+			continue
+		}
+
 	}
 	return rn, err
 }

go/asm/asm_test.go

@@ -110,3 +110,49 @@ func TestParseSingle(t *testing.T) {
 		t.Fatalf("expected %x, got %x", expect, rb)
 	}
 }
+
+func TestParseNoarg(t *testing.T) {
+	var b []byte
+	b = vm.NewLine(b, vm.HALT, nil, nil, nil)
+	s, err := vm.ToString(b)
+	log.Printf("parsing:\n%s\n", s)
+
+	r := bytes.NewBuffer(nil)
+	n, err := Parse(s, r)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n != 2 {
+		t.Fatalf("expected 8 byte write count, got %v", n)
+	}
+	rb := r.Bytes()
+	expect := []byte{0x00, vm.HALT}
+	if !bytes.Equal(rb, expect) {
+		t.Fatalf("expected %x, got %x", expect, rb)
+	}
+}
+
+func TestParserWriteMultiple(t *testing.T) {
+	var b []byte
+	b = vm.NewLine(b, vm.HALT, nil, nil, nil)
+	b = vm.NewLine(b, vm.CATCH, []string{"xyzzy"}, []byte{0x02, 0x9a}, []uint8{1})
+	b = vm.NewLine(b, vm.INCMP, []string{"inky", "pinky"}, nil, nil)
+	b = vm.NewLine(b, vm.LOAD, []string{"foo"}, []byte{42}, nil)
+	b = vm.NewLine(b, vm.MOUT, []string{"bar", "barbarbaz"}, nil, nil)
+	s, err := vm.ToString(b)
+	log.Printf("parsing:\n%s\n", s)
+
+	r := bytes.NewBuffer(nil)
+	n, err := Parse(s, r)
+	if err != nil {
+		t.Fatal(err)
+	}
+	n_expect := 2 // halt
+	n_expect += 2 + 6 + 2 + 1 // catch
+	n_expect += 2 + 5 + 6 // incmp
+	n_expect += 2 + 4 + 2 // load
+	n_expect += 2 + 4 + 10 // mout
+	if n != n_expect {
+		t.Fatalf("expected total %v bytes output, got %v", n_expect, n)
+	}
+}