hub alias: unsupported shell supported shells

Error message

hub alias: unsupported shell
supported shells: %s

What it means

After detecting (or being told) the shell, `hub alias` validates it against a whitelist: bash, zsh, sh, ksh, csh, tcsh, fish, rc (comparing filepath.Base of the shell). If the shell isn't in that list it errors with this message listing the supported shells, then exits via utils.Check.

Solutions

Use one of the supported shells: bash, zsh, sh, ksh, csh, tcsh, fish, or rc — e.g. `hub alias -s bash` and adapt the output.
If your shell is bash-compatible, generate bash output and source it: eval "$(hub alias -s bash)".
Define the alias manually in your shell's config: alias git=hub (plus shell-specific completion setup).

Example fix

// before (nushell)
hub alias nu   # unsupported shell
// after — use bash-compatible output and translate
hub alias -s bash

Defensive patterns

Strategy: validation

Validate before calling

supported="bash zsh sh ksh csh tcsh fish rc"
sh=$(basename "${SHELL:-bash}")
echo "$supported" | grep -qw "$sh" || sh=bash
eval "$(hub alias -s "$sh")"

Prevention

Only request alias output for whitelisted shells (bash zsh sh ksh csh tcsh fish rc).
For modern shells (nushell, elvish), hand-write `alias git=hub` using bash output as a base.
Use basename of $SHELL, not the full path.

When it happens

Trigger: Running `hub alias <shell>` (or implicit detection via $SHELL) with a shell outside the whitelist, e.g. `hub alias nushell`, or SHELL=/usr/bin/nu / elvish / powershell / xonsh.

Common situations: Users of modern shells (nushell, elvish, xonsh, PowerShell) trying to generate the alias; SHELL pointing to a shell with an unusual name or full path whose basename isn't recognized; typos like `hub alias zsh5`.

Related errors

AI-assisted analysis of mislav/hub@5c547ed804 (2026-09-01). Data as JSON: /api/errors/fcb8af00f621ae78. Report an issue: GitHub.

Appendix: source

Thrown at commands/alias.go:64

		cmd := "hub alias <shell>"
		if flagAliasScript {
			cmd = "hub alias -s <shell>"
		}
		utils.Check(fmt.Errorf("Error: couldn't detect shell type. Please specify your shell with `%s`", cmd))
	}

	shells := []string{"bash", "zsh", "sh", "ksh", "csh", "tcsh", "fish", "rc"}
	shell = filepath.Base(shell)
	var validShell bool
	for _, s := range shells {
		if s == shell {
			validShell = true
			break
		}
	}

	if !validShell {
		err := fmt.Errorf("hub alias: unsupported shell\nsupported shells: %s", strings.Join(shells, " "))
		utils.Check(err)
	}

	if flagAliasScript {
		var alias string
		switch shell {
		case "csh", "tcsh":
			alias = "alias git hub"
		case "rc":
			alias = "fn git { builtin hub $* }"
		default:
			alias = "alias git=hub"
		}

		ui.Println(alias)
	} else {
		var profile string
		switch shell {

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