Nushell support for Global packages (#2743)

## Summary
To load global packages with Nushell the user is required to `eval
$(devbox global shellenv)`. Nushell doesn't have an `eval` equivalent
and we need to:
1. Convert the output
2. Do this on the fly when the environment is loaded
3. Maintain previous behavior 

## How was it tested?
Locally with Nushell based setup trying to load both bash and nu
scripts.

## Community Contribution License

All community contributions in this pull request are licensed to the
project
maintainers under the terms of the
[Apache 2 License](https://www.apache.org/licenses/LICENSE-2.0).

By creating this pull request, I represent that I have the right to
license the
contributions to the project maintainers under the Apache 2 License as
stated in
the
[Community Contribution
License](https://github.com/jetify-com/opensource/blob/main/CONTRIBUTING.md#community-contribution-license).

---------

Signed-off-by: John Lago <750845+Lagoja@users.noreply.github.com>
Co-authored-by: John Lago <750845+Lagoja@users.noreply.github.com>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: 3 people

NUSHELL.md

@@ -0,0 +1,44 @@
+# Using Devbox with Nushell
+
+Devbox now supports [nushell](https://github.com/nushell/nushell) through the `--format` flag on the `shellenv` command.
+
+## Quick Start
+
+**Add this to `~/.config/nushell/env.nu`:**
+
+```nushell
+devbox global shellenv --format nushell --preserve-path-stack -r
+  | lines 
+  | parse "$env.{name} = \"{value}\""
+  | where name != null 
+  | transpose -r 
+  | into record 
+  | load-env
+```
+
+This is equivalent to bash's `eval "$(devbox global shellenv)"` and runs on every fresh shell start.
+
+---
+
+## Global Configuration
+
+To use devbox global packages with nushell, you need to load the environment similar to how bash/zsh use `eval "$(devbox global shellenv)"`.
+
+### Dynamic loading with `load-env` - eval equivalent
+
+Add this to `~/.config/nushell/env.nu` to regenerate and load devbox environment fresh every time, just like bash's `eval`:
+
+```nushell
+# Load devbox global environment dynamically (equivalent to bash eval)
+devbox global shellenv --format nushell --preserve-path-stack -r
+  | lines 
+  | parse "$env.{name} = \"{value}\""
+  | where name != null 
+  | transpose -r 
+  | into record 
+  | load-env
+```
+
+- `--format nushell` - Output in nushell syntax
+- `--preserve-path-stack` - Maintain existing PATH order if devbox is already active
+- `-r` (recompute) - Always recompute the environment, prevents "out of date" warnings

internal/boxcli/global.go

@@ -112,10 +112,12 @@ func ensureGlobalEnvEnabled(cmd *cobra.Command, args []string) error {
 			cmd.ErrOrStderr(),
 			`devbox global is not activated.
 
-Add the following line to your shell's rcfile (e.g., ~/.bashrc or ~/.zshrc)
-and restart your shell to fix this:
+Add the following line to your shell's rcfile and restart your shell:
 
+For bash/zsh (~/.bashrc or ~/.zshrc):
 	eval "$(devbox global shellenv)"
+
+For nushell: See NUSHELL.md for setup instructions
 `,
 		)
 	}

internal/boxcli/shellenv.go

@@ -24,6 +24,7 @@ type shellEnvCmdFlags struct {
 	pure              bool
 	recomputeEnv      bool
 	runInitHook       bool
+	format            string
 }
 
 // shellenvFlagDefaults are the flag default values that differ
@@ -46,7 +47,7 @@ func shellEnvCmd(defaults shellenvFlagDefaults) *cobra.Command {
 				return err
 			}
 			fmt.Fprintln(cmd.OutOrStdout(), s)
-			if !strings.HasSuffix(os.Getenv("SHELL"), "fish") {
+			if flags.format != "nushell" && !strings.HasSuffix(os.Getenv("SHELL"), "fish") {
 				fmt.Fprintln(cmd.OutOrStdout(), "hash -r")
 			}
 			return nil
@@ -81,6 +82,11 @@ func shellEnvCmd(defaults shellenvFlagDefaults) *cobra.Command {
 		"Recompute environment if needed",
 	)
 
+	command.Flags().StringVar(
+		&flags.format, "format", "bash",
+		"Output format for shell environment (nushell)",
+	)
+
 	flags.config.register(command)
 	flags.envFlag.register(command)
 
@@ -115,6 +121,15 @@ func shellEnvFunc(
 		}
 	}
 
+	// Convert format string to ShellFormat type
+	var shellFormat devopt.ShellFormat
+	switch flags.format {
+	case "nushell":
+		shellFormat = devopt.ShellFormatNushell
+	default:
+		shellFormat = devopt.ShellFormatBash
+	}
+
 	envStr, err := box.EnvExports(ctx, devopt.EnvExportsOpts{
 		EnvOptions: devopt.EnvOptions{
 			Hooks: devopt.LifecycleHooks{
@@ -136,6 +151,7 @@ func shellEnvFunc(
 		},
 		NoRefreshAlias: flags.noRefreshAlias,
 		RunHooks:       flags.runInitHook,
+		ShellFormat:    shellFormat,
 	})
 	if err != nil {
 		return "", err

internal/devbox/devbox.go

@@ -366,15 +366,21 @@ func (d *Devbox) EnvExports(ctx context.Context, opts devopt.EnvExportsOpts) (st
 		return "", err
 	}
 
-	envStr := exportify(envs)
+	// Use the appropriate export format based on shell type
+	var envStr string
+	if opts.ShellFormat == devopt.ShellFormatNushell {
+		envStr = exportifyNushell(envs)
+	} else {
+		envStr = exportify(envs)
+	}
 
 	if opts.RunHooks {
 		hooksStr := ". \"" + shellgen.ScriptPath(d.ProjectDir(), shellgen.HooksFilename) + "\""
 		envStr = fmt.Sprintf("%s\n%s;\n", envStr, hooksStr)
 	}
 
 	if !opts.NoRefreshAlias {
-		envStr += "\n" + d.refreshAlias()
+		envStr += "\n" + d.refreshAliasForShell(string(opts.ShellFormat))
 	}
 
 	return envStr, nil

internal/devbox/devopt/devboxopts.go

@@ -69,10 +69,18 @@ type UpdateOpts struct {
 	IgnoreMissingPackages bool
 }
 
+type ShellFormat string
+
+const (
+	ShellFormatBash    ShellFormat = "bash"
+	ShellFormatNushell ShellFormat = "nushell"
+)
+
 type EnvExportsOpts struct {
 	EnvOptions     EnvOptions
 	NoRefreshAlias bool
 	RunHooks       bool
+	ShellFormat    ShellFormat
 }
 
 // EnvOptions configure the Devbox Environment in the `computeEnv` function.

internal/devbox/envvars.go

@@ -60,6 +60,57 @@ func exportify(vars map[string]string) string {
 	return strings.TrimSpace(strb.String())
 }
 
+// exportifyNushell formats vars as nushell environment variable assignments.
+// Each line is of the form `$env.KEY = "value"` with special characters escaped.
+func exportifyNushell(vars map[string]string) string {
+	// Nushell protected environment variables that cannot be set manually
+	// See: https://www.nushell.sh/book/environment.html#automatic-environment-variables
+	protectedVars := map[string]bool{
+		"CURRENT_FILE":    true,
+		"FILE_PWD":        true,
+		"LAST_EXIT_CODE":  true,
+		"CMD_DURATION_MS": true,
+		"NU_VERSION":      true,
+		"PWD":             true, // Nushell manages this automatically
+	}
+
+	keys := make([]string, len(vars))
+	i := 0
+	for k := range vars {
+		keys[i] = k
+		i++
+	}
+	slices.Sort(keys) // for reproducibility
+
+	strb := strings.Builder{}
+	for _, key := range keys {
+		// Skip bash functions for nushell
+		if strings.HasPrefix(key, "BASH_FUNC_") && strings.HasSuffix(key, "%%") {
+			continue
+		}
+
+		// Skip nushell protected environment variables
+		if protectedVars[key] {
+			continue
+		}
+
+		// Nushell environment variable syntax: $env.KEY = "value"
+		strb.WriteString("$env.")
+		strb.WriteString(key)
+		strb.WriteString(` = "`)
+		for _, r := range vars[key] {
+			switch r {
+			// Escape special characters for nushell double-quoted strings
+			case '"', '\\':
+				strb.WriteRune('\\')
+			}
+			strb.WriteRune(r)
+		}
+		strb.WriteString("\"\n")
+	}
+	return strings.TrimSpace(strb.String())
+}
+
 // addEnvIfNotPreviouslySetByDevbox adds the key-value pairs from new to existing,
 // but only if the key was not previously set by devbox
 // Caveat, this won't mark the values as set by devbox automatically. Instead,

internal/devbox/refresh.go

@@ -74,3 +74,20 @@ fi`,
 		d.refreshCmd(),
 	)
 }
+
+func (d *Devbox) refreshAliasForShell(format string) string {
+	// For nushell format, provide instructions as a comment since aliases with pipes are complex
+	if format == "nushell" {
+		devboxCmd := "global shellenv --preserve-path-stack -r --format nushell"
+		if !d.isGlobal() {
+			devboxCmd = fmt.Sprintf("shellenv --preserve-path-stack -c %q --format nushell", d.projectDir)
+		}
+		return fmt.Sprintf(
+			`# To refresh your devbox environment in nushell, run:
+# devbox %s | save -f ~/.cache/devbox-env.nu; source ~/.cache/devbox-env.nu`,
+			devboxCmd,
+		)
+	}
+	// Otherwise use the original refreshAlias function
+	return d.refreshAlias()
+}

testscripts/add/add_platforms_flakeref.test.txt

@@ -4,6 +4,7 @@ exec devbox install
 
 # aside: choose armv7l-linux to verify that the add actually works on the
 # current host that is unlikely to be armv7l-linux
+
 exec devbox add github:F1bonacc1/process-compose/v1.87.0 --exclude-platform armv7l-linux
 json.superset devbox.json expected_devbox1.json