List available themes from the CLI

cmd/root.go

@@ -363,6 +363,7 @@ Environment:
 	rootCmd.AddCommand(newRunCmd())
 	rootCmd.AddCommand(newReportCmd())
 	rootCmd.AddCommand(newConfigCmd())
+	rootCmd.AddCommand(newThemeCmd())
 	rootCmd.AddCommand(newCleanCmd())
 	rootCmd.AddCommand(newCompletionCmd())
 	rootCmd.AddCommand(newKeysCmd())

cmd/theme.go

@@ -0,0 +1,43 @@
+package cmd
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/jongio/grut/internal/theme"
+	"github.com/spf13/cobra"
+)
+
+type themeListFunc func() []string
+
+func newThemeCmd() *cobra.Command {
+	themeCmd := &cobra.Command{
+		Use:   "theme",
+		Short: "Inspect grut themes",
+	}
+	themeCmd.AddCommand(newThemeListCmd(theme.ListThemes))
+	return themeCmd
+}
+
+func newThemeListCmd(list themeListFunc) *cobra.Command {
+	var asJSON bool
+
+	listCmd := &cobra.Command{
+		Use:   cmdList,
+		Short: "List available themes",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			themes := list()
+			if asJSON {
+				enc := json.NewEncoder(cmd.OutOrStdout())
+				enc.SetIndent("", "  ")
+				return enc.Encode(themes)
+			}
+			for _, name := range themes {
+				_, _ = fmt.Fprintln(cmd.OutOrStdout(), name)
+			}
+			return nil
+		},
+	}
+	listCmd.Flags().BoolVar(&asJSON, "json", false, "Print theme names as JSON")
+	return listCmd
+}

cmd/theme_test.go

@@ -0,0 +1,45 @@
+package cmd
+
+import (
+	"bytes"
+	"encoding/json"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestThemeListCommandPrintsNames(t *testing.T) {
+	cmd := newThemeListCmd(func() []string { return []string{"catppuccin", "custom"} })
+	var out bytes.Buffer
+	cmd.SetOut(&out)
+
+	err := cmd.Execute()
+
+	require.NoError(t, err)
+	assert.Equal(t, "catppuccin\ncustom\n", out.String())
+}
+
+func TestThemeListCommandPrintsJSON(t *testing.T) {
+	cmd := newThemeListCmd(func() []string { return []string{"default", "gruvbox"} })
+	cmd.SetArgs([]string{"--json"})
+	var out bytes.Buffer
+	cmd.SetOut(&out)
+
+	err := cmd.Execute()
+
+	require.NoError(t, err)
+	var names []string
+	require.NoError(t, json.Unmarshal(out.Bytes(), &names))
+	assert.Equal(t, []string{"default", "gruvbox"}, names)
+}
+
+func TestRootRegistersThemeListCommand(t *testing.T) {
+	root, cleanup := newRootCommand()
+	defer cleanup()
+
+	themeCmd, _, err := root.Find([]string{"theme", "list"})
+	require.NoError(t, err)
+	require.NotNil(t, themeCmd)
+	assert.Equal(t, cmdList, themeCmd.Name())
+}