junegunn/fzf · error

minimum height must be a non-negative integer

Error message

minimum height must be a non-negative integer

What it means

Thrown when --min-height's numeric part fails atoi or is negative. The option accepts HEIGHT optionally suffixed with '+' (meaning 'auto-grow allowed', internally stored as a negative number); if the remaining expression is not a valid non-negative integer, the error fires. Note percentages are handled elsewhere (parseSize).

Source

Thrown at src/options.go:3219

			if err != nil {
				return err
			}
			if opts.Height, err = parseHeight(str, index); err != nil {
				return err
			}
		case "--min-height":
			expr, err := nextString("minimum height required: HEIGHT[+]")
			if err != nil {
				return err
			}
			auto := false
			if strings.HasSuffix(expr, "+") {
				expr = expr[:len(expr)-1]
				auto = true
			}
			num, err := atoi(expr)
			if err != nil || num < 0 {
				return errors.New("minimum height must be a non-negative integer")
			}
			if auto {
				num *= -1
			}
			opts.MinHeight = num
		case "--no-height":
			opts.Height = heightSpec{}
		case "--no-margin":
			opts.Margin = defaultMargin()
		case "--no-padding":
			opts.Padding = defaultMargin()
		case "--no-border":
			opts.BorderShape = tui.BorderNone
		case "--border":
			hasArg, arg := optionalNextString()
			if opts.BorderShape, err = parseBorder(arg, !hasArg); err != nil {
				return err
			}

View on GitHub (pinned to bd4efa277b)

Solutions

1. Use a plain non-negative integer: `--min-height 10`
2. Put the '+' suffix for auto-grow: `--min-height 10+`
3. Sanitize computed values to integers (strip decimals, clamp >= 0) before passing

Example fix

# before
fzf --min-height +5
# after
fzf --min-height 5+

# bash: HEIGHT or HEIGHT+ only
[[ "$MH" =~ ^[0-9]+\+?$ ]] || MH=10
fzf --min-height "$MH"

min_height_ok() { [[ "$1" =~ ^[0-9]+\+?$ ]]; }

When it happens

Trigger: `--min-height abc`, `--min-height -10`, `--min-height 5.5`, or `--min-height +5` (the '+' must be a suffix: '5+', not a prefix).

Common situations: Placing the auto-grow '+' before the number; passing computed values containing spaces or decimals; confusing --min-height semantics with --height's negative/percent forms.

Related errors

• unknown action: ${spec}
• ${label} must be non-negative
• ${label} (without %) must be a non-negative integer
• invalid layout (expected: default / reverse / reverse-list)
• invalid info style (expected: default|right|hidden|inline[-r

AI-assisted analysis of junegunn/fzf@bd4efa277b (2026-08-15). Data as JSON: /api/errors/173a90888eea3976. Report an issue: GitHub.