feat: adding lowercase, trimleft, trimright, trim functions

ZEISS · Jun 25, 2024 · d80acf0 · d80acf0
1 parent 3398f1d
commit d80acf0
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Showing 3 changed files with 214 additions and 8 deletions.
diff --git a/README.md b/README.md
@@ -8,6 +8,34 @@
 
 Transform is a Go library that provides a simple way to transform data from one format to another.
 
+## Installation
+
+```bash
+go get github.com/zeiss/go-transform
+```
+
+## Usage
+
+```go
+type example struct {
+  Name string `tansform:"trim,lowercase"`
+}
+
+t := transform.New()
+e := example{Name: "  John Doe  "}
+
+if err := t.Transform(&e); err != nil {
+  log.Fatal(err)
+}
+
+fmt.Println(e.Name) // Output: john doe
+```
+
+## Transformations
+
+* `trim` - Removes leading and trailing whitespace.
+* `lowercase` - Converts the string to lowercase.
+
 ## License
 
-[MIT](/LICENSE)
+[MIT](/LICENSE)
diff --git a/transform.go b/transform.go
@@ -27,7 +27,22 @@ type FieldLevel interface {
 type Func func(fl FieldLevel) error
 
 var internalTransformers = map[string]Func{
-	"trim": trimFunc,
+	"trim":       trimFunc,
+	"trim_left":  trimLeftFunc,
+	"trim_right": trimRightFunc,
+	"lowercase":  toLowerCaseFunc,
+}
+
+func trimLeftFunc(fl FieldLevel) error {
+	fl.Field().SetString(strings.TrimLeft(fl.Field().String(), " "))
+
+	return nil
+}
+
+func trimRightFunc(fl FieldLevel) error {
+	fl.Field().SetString(strings.TrimRight(fl.Field().String(), " "))
+
+	return nil
 }
 
 func trimFunc(fl FieldLevel) error {
@@ -36,6 +51,12 @@ func trimFunc(fl FieldLevel) error {
 	return nil
 }
 
+func toLowerCaseFunc(fl FieldLevel) error {
+	fl.Field().SetString(strings.ToLower(fl.Field().String()))
+
+	return nil
+}
+
 var _ FieldLevel = &fieldLevel{}
 
 type fieldLevel struct {
@@ -100,10 +121,10 @@ func WithTagName(tagName string) TransformerOpt {
 }
 
 // Transform ...
-func Transform(name string, s interface{}) error {
+func Transform(s interface{}) error {
 	t := NewTransformer()
 
-	return t.Transform(name, s)
+	return t.Transform(s)
 }
 
 // NewTransformer ...
@@ -120,7 +141,7 @@ func NewTransformer(opts ...TransformerOpt) *TransformerImpl {
 }
 
 // Transform ...
-func (t *TransformerImpl) Transform(name string, s interface{}) error {
+func (t *TransformerImpl) Transform(s interface{}) error {
 	val := reflect.ValueOf(s)
 	if val.Kind() != reflect.Ptr {
 		return ErrNoPointer

diff --git a/transform_test.go b/transform_test.go
@@ -1,20 +1,177 @@
 package transform_test
 
 import (
+	"fmt"
+	"log"
 	"testing"
 
 	"github.com/zeiss/go-transform"
 
 	"github.com/stretchr/testify/require"
 )
 
-func TestStruct(t *testing.T) {
+func ExampleTransform() {
+	type example struct {
+		Name string `transform:"trim,lowercase"`
+	}
+
+	t := transform.NewTransformer()
+	e := example{Name: "  John Doe  "}
+
+	if err := t.Transform(&e); err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Println(e.Name)
+	// Output: john doe
+}
+
+func BenchmarkStruct(b *testing.B) {
 	trans := transform.NewTransformer()
 
 	type testStruct struct {
 		Name string `transform:"trim"`
 	}
 
+	for i := 0; i < b.N; i++ {
+		err := trans.Transform(&testStruct{Name: "  test  "})
+		require.NoError(b, err)
+	}
+}
+
+func TestStruct(t *testing.T) {
+	trans := transform.NewTransformer()
+
+	type testStruct struct {
+		Name string `transform:"trim,lowercase"`
+	}
+
+	tests := []struct {
+		name string
+		in   *testStruct
+		out  *testStruct
+	}{
+		{
+			name: "nil",
+			in:   nil,
+			out:  nil,
+		},
+		{
+			name: "empty",
+			in:   &testStruct{},
+			out:  &testStruct{},
+		},
+		{
+			name: "string",
+			in: &testStruct{
+				Name: "  TEST  ",
+			},
+			out: &testStruct{
+				Name: "test",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := trans.Transform(tt.in)
+			require.NoError(t, err)
+			require.Equal(t, tt.out, tt.in)
+		})
+	}
+}
+
+func TestStructLowercase(t *testing.T) {
+	trans := transform.NewTransformer()
+
+	type testStruct struct {
+		Name string `transform:"lowercase"`
+	}
+
+	tests := []struct {
+		name string
+		in   *testStruct
+		out  *testStruct
+	}{
+		{
+			name: "nil",
+			in:   nil,
+			out:  nil,
+		},
+		{
+			name: "empty",
+			in:   &testStruct{},
+			out:  &testStruct{},
+		},
+		{
+			name: "string",
+			in: &testStruct{
+				Name: "TEST",
+			},
+			out: &testStruct{
+				Name: "test",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := trans.Transform(tt.in)
+			require.NoError(t, err)
+			require.Equal(t, tt.out, tt.in)
+		})
+	}
+}
+
+func TestStructTrimRight(t *testing.T) {
+	trans := transform.NewTransformer()
+
+	type testStruct struct {
+		Name string `transform:"trim_right"`
+	}
+
+	tests := []struct {
+		name string
+		in   *testStruct
+		out  *testStruct
+	}{
+		{
+			name: "nil",
+			in:   nil,
+			out:  nil,
+		},
+		{
+			name: "empty",
+			in:   &testStruct{},
+			out:  &testStruct{},
+		},
+		{
+			name: "string",
+			in: &testStruct{
+				Name: "test   ",
+			},
+			out: &testStruct{
+				Name: "test",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := trans.Transform(tt.in)
+			require.NoError(t, err)
+			require.Equal(t, tt.out, tt.in)
+		})
+	}
+}
+
+func TestStructTrimLeft(t *testing.T) {
+	trans := transform.NewTransformer()
+
+	type testStruct struct {
+		Name string `transform:"trim_left"`
+	}
+
 	tests := []struct {
 		name string
 		in   *testStruct
@@ -33,7 +190,7 @@ func TestStruct(t *testing.T) {
 		{
 			name: "string",
 			in: &testStruct{
-				Name: "  test  ",
+				Name: "   test",
 			},
 			out: &testStruct{
 				Name: "test",
@@ -43,7 +200,7 @@ func TestStruct(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			err := trans.Transform(tt.name, tt.in)
+			err := trans.Transform(tt.in)
 			require.NoError(t, err)
 			require.Equal(t, tt.out, tt.in)
 		})