spectreconsole/spectre.console · error · InvalidOperationException

Console width must be greater than zero

Error message

Console width must be greater than zero

What it means

Thrown by the Profile.Width setter when the value is <= 0. Profile holds the console dimensions used for layout calculations. Width is normally auto-detected from the terminal, but can be explicitly overridden (e.g., for AnsiConsole.Create with a custom output, or for testing). A non-positive width would break every layout algorithm in Spectre.Console, so the setter rejects it immediately.

Source

Thrown at src/Spectre.Console/Profile.cs:80

                throw new InvalidOperationException("Encoding cannot be null");
            }

            _out.SetEncoding(value);
            _encoding = value;
        }
    }

    /// <summary>
    /// Gets or sets an explicit console width.
    /// </summary>
    public int Width
    {
        get => _width ?? _out.Width;
        set
        {
            if (value <= 0)
            {
                throw new InvalidOperationException("Console width must be greater than zero");
            }

            _width = value;
        }
    }

    /// <summary>
    /// Gets or sets an explicit console height.
    /// </summary>
    public int Height
    {
        get => _height ?? _out.Height;
        set
        {
            if (value <= 0)
            {
                throw new InvalidOperationException("Console height must be greater than zero");
            }

View on GitHub (pinned to 0acc92fada)

Solutions

1. Ensure the width value is positive before assigning: profile.Width = Math.Max(1, detectedWidth);
2. When using AnsiConsole.Create, pass a real terminal or a correctly-sized TestConsole.
3. In CI, set COLUMNS/LINES env vars or use a PTY so width detection returns a positive value.
4. Do not set Width explicitly unless overriding for a known terminal size — let auto-detection handle it.

Example fix

// before
var profile = new Profile(output, capabilities, encoding);
profile.Width = ConsoleHelper.GetWidth(); // may return 0

// after
var detected = ConsoleHelper.GetWidth();
profile.Width = detected > 0 ? detected : 80; // safe default

// Clamp width to positive before setting
var width = detectedWidth > 0 ? detectedWidth : 80;
AnsiConsole.Profile.Width = width;

static bool IsValidConsoleDimension(int value) => value > 0;

When it happens

Trigger: Setting AnsiConsole.Profile.Width = 0, AnsiConsole.Profile.Width = -1, or passing a non-positive width when constructing a custom console profile. Also when reading width from an environment where Console width detection returns 0 (e.g., no TTY) and that value is passed to the setter.

Common situations: CI/headless environments where the detected console width is 0 and code forwards it; testing with AnsiConsole.Create and a bad width; misconfigured AnsiConsoleSettings; custom IAnsiConsoleOutput reporting Width = 0.

Related errors

• Console height must be greater than zero
• Profile enricher of type '{enricher.GetType().FullName}' doe
• Failed to read input in non-interactive mode.
• At least one column must be specified.
• Output writer was null

AI-assisted analysis of spectreconsole/spectre.console@0acc92fada (2026-08-13). Data as JSON: /api/errors/5f839881a705f985. Report an issue: GitHub.