wip: add parseHeader function

pkg/commit/commit.go

@@ -3,11 +3,12 @@
 package commit
 
 type Commit struct {
-	Type        string
-	Scope       string
-	Description string
-	Body        string
-	Footers     []Footer
+	Type       string
+	Scope      string
+	Subject    string
+	Body       string
+	Footers    []*Footer
+	IsBreaking bool
 }
 
 type Footer struct {

pkg/commit/parser.go

@@ -1,21 +1,51 @@
 package commit
 
-import "bytes"
-
-const (
-	cr = 13
-	lf = 10
+import (
+	"bytes"
+	"errors"
+	"regexp"
 )
 
-func paragraphs(input []byte) [][]byte {
-	cln := bytes.ReplaceAll(input, []byte{cr, lf}, []byte{lf})
-	cln = bytes.ReplaceAll(cln, []byte{cr}, []byte{lf})
+const (
+	cr   = 13
+	lf   = 10
+	crlf = "\r\n"
+)
 
-	ps := bytes.Split(cln, []byte{lf, lf})
+var rHeader = regexp.MustCompile(
+	`^([\w\-]*)(?:\(([\w\$\.\/\-\* ]*)\))?(!)?\: (.*)$`,
+)
 
-	for i, p := range ps {
-		ps[i] = bytes.Trim(p, "\r\n")
+func parseHeader(header []byte) (*Commit, error) {
+	if bytes.ContainsAny(header, crlf) {
+		return nil, errors.New("header cannot span multiple lines")
 	}
 
-	return ps
+	result := rHeader.FindSubmatch(header)
+	if result == nil {
+		return &Commit{Subject: string(header)}, nil
+	}
+
+	return &Commit{
+		Type:       string(result[1]),
+		Scope:      string(result[2]),
+		Subject:    string(result[4]),
+		IsBreaking: (string(result[3]) == "!"),
+	}, nil
+}
+
+func paragraphs(input []byte) [][]byte {
+	paras := bytes.Split(normlizeLinefeeds(input), []byte{lf, lf})
+	for i, p := range paras {
+		paras[i] = bytes.Trim(p, crlf)
+	}
+
+	return paras
+}
+
+func normlizeLinefeeds(input []byte) []byte {
+	return bytes.ReplaceAll(
+		bytes.ReplaceAll(input, []byte{cr, lf}, []byte{lf}),
+		[]byte{cr}, []byte{lf},
+	)
 }

pkg/commit/parser_test.go

@@ -6,6 +6,175 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+func Test_parseHeader(t *testing.T) {
+	type args struct {
+		header []byte
+	}
+	tests := []struct {
+		name   string
+		args   args
+		want   *Commit
+		errStr string
+	}{
+		{
+			name: "non-convention commit",
+			args: args{header: []byte("add user sorting option")},
+			want: &Commit{Subject: "add user sorting option"},
+		},
+		{
+			name: "type only",
+			args: args{header: []byte("feat: add user sorting option")},
+			want: &Commit{Type: "feat", Subject: "add user sorting option"},
+		},
+		{
+			name: "type and scope",
+			args: args{header: []byte("feat(user): add user sorting option")},
+			want: &Commit{
+				Type:    "feat",
+				Scope:   "user",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "type and breaking",
+			args: args{header: []byte("feat!: add user sorting option")},
+			want: &Commit{
+				Type:       "feat",
+				Subject:    "add user sorting option",
+				IsBreaking: true,
+			},
+		},
+		{
+			name: "type, scope and breaking",
+			args: args{header: []byte("feat(user)!: add user sorting option")},
+			want: &Commit{
+				Type:       "feat",
+				Scope:      "user",
+				Subject:    "add user sorting option",
+				IsBreaking: true,
+			},
+		},
+		{
+			name: "type with underscore (_)",
+			args: args{header: []byte("int_feat: add user sorting option")},
+			want: &Commit{
+				Type:    "int_feat",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "type with hyphen (-)",
+			args: args{header: []byte("int-feat: add user sorting option")},
+			want: &Commit{
+				Type:    "int-feat",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "scope with underscopre (_)",
+			args: args{
+				header: []byte("feat(user_sort): add user sorting option"),
+			},
+			want: &Commit{
+				Type:    "feat",
+				Scope:   "user_sort",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "scope with hyphen (-)",
+			args: args{
+				header: []byte("feat(user-sort): add user sorting option"),
+			},
+			want: &Commit{
+				Type:    "feat",
+				Scope:   "user-sort",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "scope with slash (/)",
+			args: args{
+				header: []byte("feat(user/sort): add user sorting option"),
+			},
+			want: &Commit{
+				Type:    "feat",
+				Scope:   "user/sort",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "scope with period (.)",
+			args: args{
+				header: []byte("feat(user.sort): add user sorting option"),
+			},
+			want: &Commit{
+				Type:    "feat",
+				Scope:   "user.sort",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "scope with dollar sign ($)",
+			args: args{
+				header: []byte("feat($user): add user sorting option"),
+			},
+			want: &Commit{
+				Type:    "feat",
+				Scope:   "$user",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "scope with star (*)",
+			args: args{
+				header: []byte("feat(user*): add user sorting option"),
+			},
+			want: &Commit{
+				Type:    "feat",
+				Scope:   "user*",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "scope with space ( )",
+			args: args{
+				header: []byte("feat(user sort): add user sorting option"),
+			},
+			want: &Commit{
+				Type:    "feat",
+				Scope:   "user sort",
+				Subject: "add user sorting option",
+			},
+		},
+		{
+			name: "multi-line header (LF)",
+			args: args{
+				header: []byte("feat(user)!: add usersorting\noption"),
+			},
+			errStr: "header cannot span multiple lines",
+		},
+		{
+			name: "multi-line header (CR)",
+			args: args{
+				header: []byte("feat(user)!: add usersorting\roption"),
+			},
+			errStr: "header cannot span multiple lines",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := parseHeader(tt.args.header)
+
+			if tt.errStr != "" {
+				assert.Error(t, err, tt.errStr)
+			} else {
+				assert.Equal(t, tt.want, got)
+			}
+		})
+	}
+}
+
 func Test_paragraph(t *testing.T) {
 	type args struct {
 		input []byte