abiosoft/colima · error

error applying nerdctl script template: %w

Error message

error applying nerdctl script template: %w

What it means

Installing the nerdctl wrapper renders an embedded Go text/template (nerdctlScript) with values {ColimaApp: osutil.Executable(), Profile: config.CurrentProfile().ShortName}. This error fires when the template fails to parse or execute — i.e. it references a field not present on the values struct, or the embedded template asset is corrupted. It is an internal invariant break, not an environment condition.

Source

Thrown at cmd/nerdctl.go:119

		RunE: func(cmd *cobra.Command, args []string) error {
			exists := false
			if _, err := os.Stat(nerdctlCmdArgs.path); err == nil && !nerdctlCmdArgs.force && !nerdctlCmdArgs.isColimaScript {
				return fmt.Errorf("%s exists, use --force to replace", nerdctlCmdArgs.path)
			} else if err == nil {
				exists = true
			}

			var values = struct {
				ColimaApp string
				Profile   string
			}{
				ColimaApp: osutil.Executable(),
				Profile:   config.CurrentProfile().ShortName,
			}
			buf, err := util.ParseTemplate(nerdctlScript, values)
			if err != nil {
				return fmt.Errorf("error applying nerdctl script template: %w", err)
			}

			// /usr/local/bin writeable i.e. sudo not needed
			// or user-specified install path, we assume user specified path is writeable
			if nerdctlCmdArgs.usrBinWriteable || nerdctlCmdArgs.path != nerdctlDefaultInstallPath {
				if exists {
					if err := os.Rename(nerdctlCmdArgs.path, nerdctlCmdArgs.path+".moved"); err != nil {
						return fmt.Errorf("error backing up existing file: %w", err)
					}
				}
				if err := fsutil.MkdirAll("/usr/local/bin", 0755); err != nil {
					return nil
				}
				return os.WriteFile(nerdctlCmdArgs.path, buf, 0755)
			}

			// sudo is needed for the default path
			log.Println("/usr/local/bin not writable, sudo password required to install nerdctl binary")

View on GitHub (pinned to c3a5f9184d)

Solutions

1. If you patched the template: ensure every {{.Field}} exists on the values struct (ColimaApp, Profile) and the syntax is valid text/template
2. Rebuild from a clean checkout: check `git status` for modified embedded assets, then rebuild/reinstall the release binary
3. If using a released binary, report it — released templates should always render; meanwhile write the wrapper script manually

Example fix

// before
template: `#!/bin/sh
exec {{.ColimaApp}} nerdctl --profile {{.ProfileName}} "$@"`

// after
template: `#!/bin/sh
exec {{.ColimaApp}} nerdctl --profile {{.Profile}} "$@"`

// template authors: unit-test that the embedded template renders with the values struct
func TestNerdctlTemplateRenders(t *testing.T) {
    _, err := util.ParseTemplate(nerdctlScript, struct{ ColimaApp, Profile string }{"colima", "default"})
    if err != nil {
        t.Fatal(err)
    }
}

// narrow template failures precisely
var execErr template.ExecError
if errors.As(err, &execErr) {
    // a field was missing on the values struct; execErr.Name identifies the failing node
}

buf, err := util.ParseTemplate(nerdctlScript, values)
if err != nil {
    var execErr template.ExecError
    if errors.As(err, &execErr) {
        return fmt.Errorf("nerdctl template references unknown field in %q", execErr.Name)
    }
    return fmt.Errorf("error applying nerdctl script template: %w", err)
}

When it happens

Trigger: A modified nerdctlScript template referencing fields other than .ColimaApp/.Profile; a build whose embedded template got corrupted or tampered with; go:embed changes dropping the script file so ParseTemplate reads garbage.

Common situations: Contributors editing the template during development; CI builds from a dirty tree; essentially never seen in released binaries.

Related errors

• error retrieving current runtime: empty value
• error reading ssh config: %w
• error at '%s': %w
• cannot make dir: %w
• pid file not found: %w

AI-assisted analysis of abiosoft/colima@c3a5f9184d (2026-08-15). Data as JSON: /api/errors/e616ab296b94faec. Report an issue: GitHub.