chore: テストコード追加 (#15)

main.go

@@ -11,8 +11,12 @@ func init() {
 }
 
 func main() {
-	if err := RootCommand.Execute(); err != nil {
+	if err := Main(); err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(-1)
 	}
 }
+
+func Main() error {
+	return RootCommand.Execute()
+}

main_test.go

@@ -1,11 +1,100 @@
 package main
 
 import (
+	"os"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 )
 
 func TestMain(t *testing.T) {
-	assert.Equal(t, 1, 1)
+	tests := []struct {
+		desc      string
+		args      []string
+		wantError bool
+	}{
+		{
+			desc:      "正常系: align left",
+			args:      []string{"align", "left", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align l",
+			args:      []string{"align", "l", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align center",
+			args:      []string{"align", "center", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align c",
+			args:      []string{"align", "c", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align right",
+			args:      []string{"align", "right", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align r",
+			args:      []string{"align", "r", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align vertical-top",
+			args:      []string{"align", "vertical-top", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align vt",
+			args:      []string{"align", "vt", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align vertical-center",
+			args:      []string{"align", "vertical-center", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align vc",
+			args:      []string{"align", "vc", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align vertical-bottom",
+			args:      []string{"align", "vertical-bottom", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align vb",
+			args:      []string{"align", "vb", "README.adoc"},
+			wantError: false,
+		},
+		{
+			desc:      "正常系: align --help",
+			args:      []string{"align", "--help"},
+			wantError: false,
+		},
+		{
+			desc:      "異常系: 存在しないサブコマンド",
+			args:      []string{"align", "foobar"},
+			wantError: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.desc, func(t *testing.T) {
+			assert := assert.New(t)
+			os.Args = tt.args
+			err := Main()
+			if tt.wantError {
+				assert.Error(err)
+				return
+			}
+			assert.NoError(err)
+		})
+	}
 }