feat: add Distinct

stream/stream_test.go

@@ -15,7 +15,7 @@ func TestFromSlice(t *testing.T) {
 }
 
 func TestFromRange(t *testing.T) {
-	assert := internal.NewAssert(t, "TestFromSlice")
+	assert := internal.NewAssert(t, "TestFromRange")
 
 	s1 := FromRange(1, 5, 1)
 	s2 := FromRange(1.1, 5.0, 1.0)
@@ -23,3 +23,35 @@ func TestFromRange(t *testing.T) {
 	assert.Equal([]int{1, 2, 3, 4, 5}, s1.ToSlice())
 	assert.Equal([]float64{1.1, 2.1, 3.1, 4.1}, s2.ToSlice())
 }
+
+func TestStream_Distinct(t *testing.T) {
+	assert := internal.NewAssert(t, "TestStream_Distinct")
+
+	nums := FromSlice([]int{1, 2, 2, 3, 3, 3})
+	distinctNums := nums.Distinct()
+
+	assert.Equal([]int{1, 2, 2, 3, 3, 3}, nums.ToSlice())
+	assert.Equal([]int{1, 2, 3}, distinctNums.ToSlice())
+
+	type Person struct {
+		Id   string
+		Name string
+		Age  uint
+	}
+
+	people := []Person{
+		{Id: "001", Name: "Tom", Age: 10},
+		{Id: "001", Name: "Tom", Age: 10},
+		{Id: "002", Name: "Jim", Age: 20},
+		{Id: "003", Name: "Mike", Age: 30},
+	}
+
+	stream := FromSlice(people)
+	distinctStream := stream.Distinct()
+
+	// {[{001 Tom 10} {001 Tom 10} {002 Jim 20} {003 Mike 30}]}
+	t.Log(stream)
+
+	// {[{001 Tom 10} {002 Jim 20} {003 Mike 30}]}
+	t.Log(distinctStream)
+}