abiosoft/colima · error

error parsing template: %w

Error message

error parsing template: %w

What it means

ParseTemplate (util/template.go:23) calls text/template's Parse on the body string; this error wraps a syntax-level failure, meaning the template text itself is malformed (unclosed {{, stray }}, bad pipeline, invalid action). colima uses ParseTemplate to render Lima config snippets and provisioning scripts (e.g. the disk mount script), so the body is normally a hardcoded, already-valid template. Seeing this error means a template literal was edited and broke Go template syntax.

Source

Thrown at util/template.go:23

	"fmt"
	"os"
	"text/template"
)

// WriteTemplate writes template with body to file after applying values.
func WriteTemplate(body string, file string, values any) error {
	b, err := ParseTemplate(body, values)
	if err != nil {
		return err
	}
	return os.WriteFile(file, b, 0644)
}

// ParseTemplate parses template with body and values and returns the resulting bytes.
func ParseTemplate(body string, values any) ([]byte, error) {
	t, err := template.New("").Parse(body)
	if err != nil {
		return nil, fmt.Errorf("error parsing template: %w", err)
	}

	var b bytes.Buffer
	if err := t.Execute(&b, values); err != nil {
		return nil, fmt.Errorf("error executing template: %w", err)
	}

	return b.Bytes(), err
}

View on GitHub (pinned to c3a5f9184d)

Solutions

1. Fix the template syntax: balance every {{ with }} and validate action syntax against text/template docs
2. Escape literal braces as {{"{{"}} and {{"}}"}} instead of raw {{ }}
3. Add a unit test that runs ParseTemplate over the embedded template body so syntax errors fail at build/test time
4. If the text is not meant to be a template at all, pass it through directly instead of ParseTemplate

Example fix

// before
body := "echo {{.InstanceId" // unterminated action
b, err := util.ParseTemplate(body, values)

// after
body := "echo {{.InstanceId}}"
b, err := util.ParseTemplate(body, values)

// pre-parse templates at startup/test time to catch syntax errors early
func templateIsValid(body string) bool {
    _, err := template.New("").Parse(body)
    return err == nil
}

b, err := util.ParseTemplate(body, values)
if err != nil {
    // the wrapped cause names the line/column of the syntax error — surface it verbatim
    return fmt.Errorf("rendering failed: %w", err)
}

When it happens

Trigger: Calling util.ParseTemplate(body, values) with a body like "{{.InstanceId" (missing closing braces), "{{ end }}" without an opening block, or a body containing a literal "{{" that was meant as plain text.

Common situations: Editing embedded template literals (disk scripts, cloud-init, Lima override files) in a colima fork and introducing a typo; user-supplied strings containing raw braces being concatenated into a template; copy-pasting shell scripts with {{ }} into a template without escaping.

Related errors

• error executing template: %w
• invalid pid: %v
• error applying nerdctl script template: %w
• error reading embedded file: %w
• error reading template file: %w

AI-assisted analysis of abiosoft/colima@c3a5f9184d (2026-08-15). Data as JSON: /api/errors/2f44495c5b82ad1a. Report an issue: GitHub.