feat: allow git remote names in gh repo set-default

When specifying a repository for `gh repo set-default`, users can now
use a git remote name (e.g., "origin", "upstream") instead of the
full OWNER/REPO format.

The command first checks if the argument is a git remote name. If
found, it uses the corresponding repository. Otherwise, it falls
back to parsing the argument as OWNER/REPO format.

Example:
  gh repo set-default origin

Fixes cli#9149

Signed-off-by: majiayu000 <1835304752@qq.com>

Author: majiayu000

pkg/cmd/repo/setdefault/setdefault.go

@@ -70,6 +70,9 @@ func NewCmdSetDefault(f *cmdutil.Factory, runF func(*SetDefaultOptions) error) *
 			# Set a repository explicitly
 			$ gh repo set-default owner/repo
 
+			# Set a repository using a git remote name
+			$ gh repo set-default origin
+
 			# View the current default repository
 			$ gh repo set-default --view
 
@@ -79,24 +82,35 @@ func NewCmdSetDefault(f *cmdutil.Factory, runF func(*SetDefaultOptions) error) *
 		`),
 		Args: cobra.MaximumNArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
+			if isLocal, err := opts.GitClient.IsLocalGitRepo(cmd.Context()); err != nil {
+				return err
+			} else if !isLocal {
+				return errors.New("must be run from inside a git repository")
+			}
+
 			if len(args) > 0 {
-				var err error
-				opts.Repo, err = ghrepo.FromFullName(args[0])
-				if err != nil {
-					return err
+				// First, try to find argument as a git remote name
+				if !strings.Contains(args[0], "/") && opts.Remotes != nil {
+					if remotes, err := opts.Remotes(); err == nil {
+						if remote, err := remotes.FindByName(args[0]); err == nil {
+							opts.Repo = remote.Repo
+						}
+					}
+				}
+				// If not found as remote name, try parsing as OWNER/REPO
+				if opts.Repo == nil {
+					var err error
+					opts.Repo, err = ghrepo.FromFullName(args[0])
+					if err != nil {
+						return err
+					}
 				}
 			}
 
 			if !opts.ViewMode && !opts.IO.CanPrompt() && opts.Repo == nil {
 				return cmdutil.FlagErrorf("repository required when not running interactively")
 			}
 
-			if isLocal, err := opts.GitClient.IsLocalGitRepo(cmd.Context()); err != nil {
-				return err
-			} else if !isLocal {
-				return errors.New("must be run from inside a git repository")
-			}
-
 			if runF != nil {
 				return runF(opts)
 			}

pkg/cmd/repo/setdefault/setdefault_test.go

@@ -21,6 +21,7 @@ func TestNewCmdSetDefault(t *testing.T) {
 	tests := []struct {
 		name     string
 		gitStubs func(*run.CommandStubber)
+		remotes  func() (context.Remotes, error)
 		input    string
 		output   SetDefaultOptions
 		wantErr  bool
@@ -43,11 +44,13 @@ func TestNewCmdSetDefault(t *testing.T) {
 			output: SetDefaultOptions{Repo: ghrepo.New("cli", "cli")},
 		},
 		{
-			name:     "invalid repo argument",
-			gitStubs: func(cs *run.CommandStubber) {},
-			input:    "some_invalid_format",
-			wantErr:  true,
-			errMsg:   `expected the "[HOST/]OWNER/REPO" format, got "some_invalid_format"`,
+			name: "invalid repo argument",
+			gitStubs: func(cs *run.CommandStubber) {
+				cs.Register(`git rev-parse --git-dir`, 0, ".git")
+			},
+			input:   "some_invalid_format",
+			wantErr: true,
+			errMsg:  `expected the "[HOST/]OWNER/REPO" format, got "some_invalid_format"`,
 		},
 		{
 			name: "view flag",
@@ -74,6 +77,22 @@ func TestNewCmdSetDefault(t *testing.T) {
 			wantErr: true,
 			errMsg:  "must be run from inside a git repository",
 		},
+		{
+			name: "remote name argument",
+			gitStubs: func(cs *run.CommandStubber) {
+				cs.Register(`git rev-parse --git-dir`, 0, ".git")
+			},
+			remotes: func() (context.Remotes, error) {
+				return context.Remotes{
+					{
+						Remote: &git.Remote{Name: "origin"},
+						Repo:   ghrepo.New("OWNER", "REPO"),
+					},
+				}, nil
+			},
+			input:  "origin",
+			output: SetDefaultOptions{Repo: ghrepo.New("OWNER", "REPO")},
+		},
 	}
 
 	for _, tt := range tests {
@@ -84,6 +103,7 @@ func TestNewCmdSetDefault(t *testing.T) {
 		f := &cmdutil.Factory{
 			IOStreams: io,
 			GitClient: &git.Client{GitPath: "/fake/path/to/git"},
+			Remotes:   tt.remotes,
 		}
 
 		var gotOpts *SetDefaultOptions