feat(Go-StudyExample):2021/02/09:新增merge源码阅读和单测代码

SourceAnalysisAndTool/mergo@v0.3.11/merge_test.go

@@ -0,0 +1,88 @@
+package mergo_test
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/imdario/mergo"
+)
+
+type transformer struct {
+	m map[reflect.Type]func(dst, src reflect.Value) error
+}
+
+func (s *transformer) Transformer(t reflect.Type) func(dst, src reflect.Value) error {
+	if fn, ok := s.m[t]; ok {
+		return fn
+	}
+	return nil
+}
+
+type foo struct {
+	s   string
+	Bar *bar
+}
+
+type bar struct {
+	i int
+	s map[string]string
+}
+
+func TestMergeWithTransformerNilStruct(t *testing.T) {
+	a := foo{s: "foo"}
+	b := foo{Bar: &bar{i: 2, s: map[string]string{"foo": "bar"}}}
+
+	if err := mergo.Merge(&a, &b, mergo.WithOverride, mergo.WithTransformers(&transformer{
+		m: map[reflect.Type]func(dst, src reflect.Value) error{
+			reflect.TypeOf(&bar{}): func(dst, src reflect.Value) error {
+				// Do sthg with Elem
+				t.Log(dst.Elem().FieldByName("i"))
+				t.Log(src.Elem())
+				return nil
+			},
+		},
+	})); err != nil {
+		t.Error(err)
+	}
+
+	if a.s != "foo" {
+		t.Errorf("b not merged in properly: a.s.Value(%s) != expected(%s)", a.s, "foo")
+	}
+
+	if a.Bar == nil {
+		t.Errorf("b not merged in properly: a.Bar shouldn't be nil")
+	}
+}
+
+func TestMergeNonPointer(t *testing.T) {
+	dst := bar{
+		i: 1,
+	}
+	src := bar{
+		i: 2,
+		s: map[string]string{
+			"a": "1",
+		},
+	}
+	want := mergo.ErrNonPointerAgument
+
+	if got := mergo.Merge(dst, src); got != want {
+		t.Errorf("want: %s, got: %s", want, got)
+	}
+}
+
+func TestMapNonPointer(t *testing.T) {
+	dst := make(map[string]bar)
+	src := map[string]bar{
+		"a": {
+			i: 2,
+			s: map[string]string{
+				"a": "1",
+			},
+		},
+	}
+	want := mergo.ErrNonPointerAgument
+	if got := mergo.Merge(dst, src); got != want {
+		t.Errorf("want: %s, got: %s", want, got)
+	}
+}