write some tests

vm/vm_test.go

@@ -0,0 +1,83 @@
+package vm
+
+import (
+	. "testing"
+
+	"github.com/mediocregopher/ginger/lang"
+)
+
+func TestCompiler(t *T) {
+	mkcmd := func(a lang.Atom, args ...lang.Term) lang.Tuple {
+		if len(args) == 1 {
+			return lang.Tuple{a, args[0]}
+		}
+		return lang.Tuple{a, lang.Tuple(args)}
+	}
+	mkint := func(i string) lang.Tuple {
+		return lang.Tuple{Int, lang.Const(i)}
+	}
+
+	type test struct {
+		in  []lang.Term
+		exp uint64
+	}
+
+	one := mkint("1")
+	two := mkint("2")
+	foo := lang.Atom("foo")
+	bar := lang.Atom("bar")
+	baz := lang.Atom("baz")
+
+	tests := []test{
+		{
+			in:  []lang.Term{one},
+			exp: 1,
+		},
+		{
+			in: []lang.Term{
+				mkcmd(Add, mkcmd(Tuple, one, two)),
+			},
+			exp: 3,
+		},
+		{
+			in: []lang.Term{
+				mkcmd(Assign, foo, one),
+				mkcmd(Add, mkcmd(Tuple, mkcmd(Var, foo), two)),
+			},
+			exp: 3,
+		},
+		{
+			in: []lang.Term{
+				mkcmd(Assign, foo, mkcmd(Tuple, one, two)),
+				mkcmd(Add, mkcmd(Var, foo)),
+			},
+			exp: 3,
+		},
+		{
+			in: []lang.Term{
+				mkcmd(Assign, foo, mkcmd(Tuple, one, two)),
+				mkcmd(Assign, bar, mkcmd(Add, mkcmd(Var, foo))),
+				mkcmd(Assign, baz, mkcmd(Add, mkcmd(Var, foo))),
+				mkcmd(Add, mkcmd(Tuple, mkcmd(Var, bar), mkcmd(Var, baz))),
+			},
+			exp: 6,
+		},
+	}
+
+	for _, test := range tests {
+		t.Logf("testing program: %v", test.in)
+		mod, err := Build(test.in...)
+		if err != nil {
+			t.Fatalf("building failed: %s", err)
+		}
+
+		out, err := mod.Run()
+		if err != nil {
+			mod.Dump()
+			t.Fatalf("running failed: %s", err)
+		} else if out != test.exp {
+			mod.Dump()
+			t.Fatalf("expected result %T:%v, got %T:%v", test.exp, test.exp, out, out)
+		}
+	}
+}