Merge pull request chrislusf#53 from justicezyx/pr

Add utils_test.go.

flow/utils_test.go

@@ -0,0 +1,48 @@
+package flow
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestGuessFunctionOutputType(t *testing.T) {
+	f := func(i int) int {
+		return 1
+	}
+	if got, want := guessFunctionOutputType(f), reflect.TypeOf(1); got != want {
+		t.Errorf("Type mismatch, got %v want %v", got, want)
+	}
+}
+
+func TestGuessKey(t *testing.T) {
+	testStruct := struct {
+		A string
+	}{
+		A: "test",
+	}
+	cases := []struct {
+		input reflect.Value
+		want  reflect.Value
+	}{{
+		input: reflect.ValueOf(1),
+		want:  reflect.ValueOf(1),
+	}, {
+		input: reflect.ValueOf("test"),
+		want:  reflect.ValueOf("test"),
+	}, {
+		input: reflect.ValueOf([1]int{1}),
+		want:  reflect.ValueOf(1),
+	}, {
+		input: reflect.ValueOf([]int{1}),
+		want:  reflect.ValueOf(1),
+	}, {
+		input: reflect.ValueOf(testStruct),
+		want:  reflect.ValueOf("test"),
+	}}
+
+	for _, c := range cases {
+		if got := guessKey(c.input); got.Interface() != c.want.Interface() {
+			t.Errorf("Got %v want %v", got, c.want)
+		}
+	}
+}