feat: support convert

README.md

@@ -53,26 +53,37 @@ and you will get file user_tag.go:
 //go:generate gtag -types User -tags bson .
 package tutorial
 
-import "reflect"
+import (
+	"reflect"
+	"strings"
+)
 
 var (
 	// ...
 )
 
+// UserTags indicate tags of type User
 type UserTags struct {
-	Id    string
-	Name  string
-	Email string
+	Id    string // `bson:"_id"`
+	Name  string // `bson:"name"`
+	Email string // `bson:"email"`
 }
 
-func (User) Tags(tag string) UserTags {
+// Tags return specified tags of User
+func (User) Tags(tag string, convert ...func(string) string) UserTags {
+	conv := func(in string) string { return strings.TrimSpace(strings.Split(in, ",")[0]) }
+	if len(convert) > 0 && convert[0] != nil {
+		conv = convert[0]
+	}
+	_ = conv
 	return UserTags{
-		Id:    tagOfUserId.Get(tag),
-		Name:  tagOfUserName.Get(tag),
-		Email: tagOfUserEmail.Get(tag),
+		Id:    conv(tagOfUserId.Get(tag)),
+		Name:  conv(tagOfUserName.Get(tag)),
+		Email: conv(tagOfUserEmail.Get(tag)),
 	}
 }
 
+// TagsBson is alias of Tags("bson")
 func (v User) TagsBson() UserTags {
 	return v.Tags("bson")
 }

go.mod

@@ -4,6 +4,6 @@ go 1.14
 
 require (
 	github.com/gochore/uniq v1.0.0
-	github.com/pmezard/go-difflib v1.0.0
+	github.com/google/go-cmp v0.4.0
 	golang.org/x/tools v0.0.0-20200505023115-26f46d2f7ef8
 )

go.sum

@@ -1,7 +1,7 @@
 github.com/gochore/uniq v1.0.0 h1:qBA8Jm9GhSojZ8vsCI2h5FJGonmItjY9NLBPUaciOYk=
 github.com/gochore/uniq v1.0.0/go.mod h1:zxZBO4/6PcgNuYMrlJCUKOEEpxSejbD6R53GUpSHelk=
-github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
-github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/google/go-cmp v0.4.0 h1:xsAVV57WRhGj6kEIi8ReJzQlHHqcBYCElAvkovg3B/4=
+github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=

internal/gtag/gtag.go

@@ -76,7 +76,7 @@ func generateFile(ctx context.Context, cmd, file string, types []string, tags []
 	}
 	pkg := f.Name.Name
 
-	fieldM := map[string][]string{}
+	fieldM := map[string][]*ast.Field{}
 	for _, typ := range types {
 		fields, ok := parseStructField(f, typ)
 		if ok {
@@ -95,9 +95,23 @@ func generateFile(ctx context.Context, cmd, file string, types []string, tags []
 
 	for _, typ := range types {
 		if fields, ok := fieldM[typ]; ok {
+			var tmpFields []templateDataTypeField
+			for _, field := range fields {
+				tag := ""
+				if field.Tag != nil {
+					tag = field.Tag.Value
+				}
+				for _, name := range field.Names {
+					tmpFields = append(tmpFields, templateDataTypeField{
+						Name: name.Name,
+						Tag:  tag,
+					})
+				}
+			}
+
 			data.Types = append(data.Types, templateDataType{
 				Name:   typ,
-				Fields: fields,
+				Fields: tmpFields,
 			})
 		}
 	}
@@ -140,7 +154,7 @@ func loadFile(name string) (*ast.File, error) {
 	return parser.ParseFile(token.NewFileSet(), name, f, 0)
 }
 
-func parseStructField(f *ast.File, name string) ([]string, bool) {
+func parseStructField(f *ast.File, name string) ([]*ast.Field, bool) {
 	var fields []*ast.Field
 	found := false
 
@@ -166,12 +180,5 @@ func parseStructField(f *ast.File, name string) ([]string, bool) {
 		return nil, found
 	}
 
-	var ret []string
-	for _, field := range fields {
-		for _, v := range field.Names {
-			ret = append(ret, v.Name)
-		}
-	}
-
-	return ret, found
+	return fields, found
 }

internal/gtag/template_test.go

@@ -3,7 +3,7 @@ package gtag
 import (
 	"testing"
 
-	"github.com/pmezard/go-difflib/difflib"
+	"github.com/google/go-cmp/cmp"
 )
 
 func Test_execute(t *testing.T) {
@@ -22,8 +22,17 @@ func Test_execute(t *testing.T) {
 					Package: "test",
 					Types: []templateDataType{
 						{
-							Name:   "test",
-							Fields: []string{"A", "b"},
+							Name: "test",
+							Fields: []templateDataTypeField{
+								{
+									Name: "A",
+									Tag:  `json:"a"`,
+								},
+								{
+									Name: "b",
+									Tag:  ``,
+								},
+							},
 						},
 					},
 					Tags: []templateDataTag{
@@ -45,7 +54,10 @@ func Test_execute(t *testing.T) {
 //go:generate 
 package test
 
-import "reflect"
+import (
+	"reflect"
+	"strings"
+)
 
 
 
@@ -66,15 +78,23 @@ var (
 
 // testTags indicate tags of type test
 type testTags struct {
-	A string
-	b string
+	A string // json:"a"
+	b string // 
 }
 
 // Tags return specified tags of test
-func (test) Tags(tag string) testTags {
+func (test) Tags(tag string, convert ...func(string) string) testTags {
+	conv := func(in string) string { return strings.TrimSpace(strings.Split(in, ",")[0]) }
+	if len(convert) > 0 {
+		conv = convert[0]
+	}
+	if conv == nil {
+		conv = func(in string) string { return in }
+	}
+	_ = conv
 	return testTags{
-		A: tagOftestA.Get(tag),
-		b: tagOftestb.Get(tag),
+		A: conv(tagOftestA.Get(tag)),
+		b: conv(tagOftestb.Get(tag)),
 	}
 }
 
@@ -99,14 +119,7 @@ func (v test) TagsBson() testTags {
 		t.Run(tt.name, func(t *testing.T) {
 			if got := string(execute(tt.args.data)); got != tt.want {
 				t.Errorf("execute() = %v, want %v", got, tt.want)
-				diff := difflib.UnifiedDiff{
-					A:        difflib.SplitLines(got),
-					B:        difflib.SplitLines(tt.want),
-					FromFile: "got",
-					ToFile:   "want",
-				}
-				text, _ := difflib.GetUnifiedDiffString(diff)
-				t.Log(text)
+				t.Error(cmp.Diff(got, tt.want))
 			}
 		})
 	}

test/internal/regular/empty_tag_test.go

@@ -2,12 +2,14 @@ package regular
 
 import (
 	"reflect"
+	"strings"
 	"testing"
 )
 
 func TestEmpty_Tags(t *testing.T) {
 	type args struct {
-		tag string
+		tag     string
+		convert []func(string) string
 	}
 	tests := []struct {
 		name string
@@ -21,11 +23,27 @@ func TestEmpty_Tags(t *testing.T) {
 			},
 			want: EmptyTags{},
 		},
+		{
+			name: "convert ToUpper",
+			args: args{
+				tag:     "json",
+				convert: []func(string) string{strings.ToUpper},
+			},
+			want: EmptyTags{},
+		},
+		{
+			name: "convert nil",
+			args: args{
+				tag:     "json",
+				convert: []func(string) string{nil},
+			},
+			want: EmptyTags{},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			em := Empty{}
-			if got := em.Tags(tt.args.tag); !reflect.DeepEqual(got, tt.want) {
+			if got := em.Tags(tt.args.tag, tt.args.convert...); !reflect.DeepEqual(got, tt.want) {
 				t.Errorf("Tags() = %v, want %v", got, tt.want)
 			}
 		})

test/internal/regular/user.go

@@ -2,7 +2,7 @@ package regular
 
 type User struct {
 	Id    int      `json:"id"`
-	Name  UserName `json:"name"`
+	Name  UserName `json:"name,omitempty"`
 	Email string   `json:"email"`
 	age   int
 }