label: Add delete subcommand

After supporting label creation, it just seems logical to support
the reverse action as well.

cmd/label_delete.go

@@ -0,0 +1,42 @@
+package cmd
+
+import (
+	"log"
+
+	"github.com/rsteube/carapace"
+	"github.com/spf13/cobra"
+	"github.com/zaquestion/lab/internal/action"
+	lab "github.com/zaquestion/lab/internal/gitlab"
+)
+
+var labelDeleteCmd = &cobra.Command{
+	Use:              "delete [remote] <name>",
+	Aliases:          []string{"remove"},
+	Short:            "Deletes an existing label",
+	Long:             ``,
+	PersistentPreRun: LabPersistentPreRun,
+	Args:             cobra.MinimumNArgs(1),
+	Run: func(cmd *cobra.Command, args []string) {
+		rn, name, err := parseArgsRemoteAndProject(args)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		labels, err := MapLabels(rn, []string{name})
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		err = lab.LabelDelete(rn, labels[0])
+		if err != nil {
+			log.Fatal(err)
+		}
+	},
+}
+
+func init() {
+	labelCmd.AddCommand(labelDeleteCmd)
+	carapace.Gen(labelCmd).PositionalCompletion(
+		action.Remotes(),
+	)
+}

cmd/label_test.go

@@ -0,0 +1,60 @@
+package cmd
+
+import (
+	"os/exec"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func Test_labelCmd(t *testing.T) {
+	t.Parallel()
+	repo := copyTestRepo(t)
+	t.Run("prepare", func(t *testing.T) {
+		cmd := exec.Command("sh", "-c", labBinaryPath+` label list lab-testing | grep -q 'test-label' && `+labBinaryPath+` label delete test-label`)
+		cmd.Dir = repo
+
+		b, err := cmd.CombinedOutput()
+		if err != nil {
+			t.Log(string(b))
+			//t.Fatal(err)
+		}
+	})
+	t.Run("create", func(t *testing.T) {
+		cmd := exec.Command(labBinaryPath, "label", "create", "lab-testing", "test-label",
+			"--color", "crimson",
+			"--description", "Reddish test label",
+		)
+		cmd.Dir = repo
+
+		_ = cmd.Run()
+
+		cmd = exec.Command(labBinaryPath, "label", "list", "lab-testing")
+		cmd.Dir = repo
+
+		b, err := cmd.CombinedOutput()
+		out := string(b)
+		if err != nil {
+			t.Log(out)
+			//t.Fatal(err)
+		}
+		require.Contains(t, out, "test-label")
+	})
+	t.Run("delete", func(t *testing.T) {
+		cmd := exec.Command(labBinaryPath, "label", "delete", "lab-testing", "test-label")
+		cmd.Dir = repo
+
+		_ = cmd.Run()
+
+		cmd = exec.Command(labBinaryPath, "label", "list", "lab-testing")
+		cmd.Dir = repo
+
+		b, err := cmd.CombinedOutput()
+		out := string(b)
+		if err != nil {
+			t.Log(out)
+			//t.Fatal(err)
+		}
+		require.NotContains(t, out, "test-label")
+	})
+}

internal/gitlab/gitlab.go

@@ -777,6 +777,19 @@ func LabelCreate(project string, opts *gitlab.CreateLabelOptions) error {
 	return err
 }
 
+// LabelDelete removes a project label
+func LabelDelete(project, name string) error {
+	p, err := FindProject(project)
+	if err != nil {
+		return err
+	}
+
+	_, err = lab.Labels.DeleteLabel(p.ID, &gitlab.DeleteLabelOptions{
+		Name: &name,
+	})
+	return err
+}
+
 // ProjectSnippetCreate creates a snippet in a project
 func ProjectSnippetCreate(pid interface{}, opts *gitlab.CreateProjectSnippetOptions) (*gitlab.Snippet, error) {
 	snip, _, err := lab.ProjectSnippets.CreateSnippet(pid, opts)