diff --git a/pkg/controllers/binding/common_test.go b/pkg/controllers/binding/common_test.go
new file mode 100644
index 000000000..77c76840f
--- /dev/null
+++ b/pkg/controllers/binding/common_test.go
@@ -0,0 +1,124 @@
+package binding
+
+import (
+	"reflect"
+	"testing"
+
+	workv1alpha2 "github.com/karmada-io/karmada/pkg/apis/work/v1alpha2"
+)
+
+func Test_mergeTargetClusters(t *testing.T) {
+	tests := []struct {
+		name                      string
+		targetClusters            []workv1alpha2.TargetCluster
+		requiredByBindingSnapshot []workv1alpha2.BindingSnapshot
+		want                      []workv1alpha2.TargetCluster
+	}{
+		{
+			name: "the same cluster",
+			targetClusters: []workv1alpha2.TargetCluster{
+				{
+					Name:     "foo",
+					Replicas: 1,
+				},
+			},
+			requiredByBindingSnapshot: []workv1alpha2.BindingSnapshot{
+				{
+					Clusters: []workv1alpha2.TargetCluster{
+						{
+							Name:     "foo",
+							Replicas: 1,
+						},
+					},
+				},
+			},
+			want: []workv1alpha2.TargetCluster{
+				{
+					Name:     "foo",
+					Replicas: 1,
+				},
+			},
+		},
+		{
+			name: "different clusters",
+			targetClusters: []workv1alpha2.TargetCluster{
+				{
+					Name:     "foo",
+					Replicas: 1,
+				},
+			},
+			requiredByBindingSnapshot: []workv1alpha2.BindingSnapshot{
+				{
+					Clusters: []workv1alpha2.TargetCluster{
+						{
+							Name:     "bar",
+							Replicas: 1,
+						},
+					},
+				},
+			},
+			want: []workv1alpha2.TargetCluster{
+				{
+					Name:     "foo",
+					Replicas: 1,
+				},
+				{
+					Name:     "bar",
+					Replicas: 1,
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := mergeTargetClusters(tt.targetClusters, tt.requiredByBindingSnapshot); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("mergeTargetClusters() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func Test_transScheduleResultToMap(t *testing.T) {
+	tests := []struct {
+		name           string
+		scheduleResult []workv1alpha2.TargetCluster
+		want           map[string]int64
+	}{
+		{
+			name: "one cluster",
+			scheduleResult: []workv1alpha2.TargetCluster{
+				{
+					Name:     "foo",
+					Replicas: 1,
+				},
+			},
+			want: map[string]int64{
+				"foo": 1,
+			},
+		},
+		{
+			name: "different clusters",
+			scheduleResult: []workv1alpha2.TargetCluster{
+				{
+					Name:     "foo",
+					Replicas: 1,
+				},
+				{
+					Name:     "bar",
+					Replicas: 2,
+				},
+			},
+			want: map[string]int64{
+				"foo": 1,
+				"bar": 2,
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := transScheduleResultToMap(tt.scheduleResult); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("transScheduleResultToMap() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}