Working on SCMA-compatible assembler.

asm/expr/expression_test.go

@@ -0,0 +1,50 @@
+package expr
+
+import (
+	"testing"
+)
+
+func TestExpressionString(t *testing.T) {
+	tests := []struct {
+		expr E
+		want string
+	}{
+		{
+			E{},
+			"?",
+		},
+		{
+			E{Op: OpLeaf, Text: "*"},
+			"*",
+		},
+		{
+			E{
+				Op:    OpPlus,
+				Left:  &E{Op: OpLeaf, Text: "Label"},
+				Right: &E{Op: OpLeaf, Val: 42},
+			},
+			"(+ Label $002a)",
+		},
+		{
+			E{
+				Op:    OpMinus,
+				Left:  &E{Op: OpLeaf, Text: "Label"},
+				Right: &E{Op: OpLeaf, Val: 42},
+			},
+			"(- Label $002a)",
+		},
+		{
+			E{
+				Op:   OpMinus,
+				Left: &E{Op: OpLeaf, Val: 42},
+			},
+			"(- $002a)",
+		},
+	}
+	for i, tt := range tests {
+		got := tt.expr.String()
+		if got != tt.want {
+			t.Errorf(`%d: want String(expr)="%s"; got "%s"`, i, tt.want, got)
+		}
+	}
+}