Colors are specific color values and their attributes, like…

Error message

Colors are specific color values and their attributes, like 'brightred', or 'blue'

What it means

`Color` values parsed from git config must be a valid color name ('red', 'brightred', 'blue', ...), an ANSI number, or a color value combined with attributes like 'bold' or 'underline'. `color_err` raises this Error with the offending input when `TryFrom<&BStr> for Color` (and the `from_str` path) fails to match any known color or attribute token.

Solutions

Use a valid color name ('normal', 'black', 'red', 'green', 'yellow', 'blue', 'magenta', 'cyan', 'white', optionally 'bright'-prefixed) optionally followed by attributes ('bold', 'dim', 'ul', 'blink', 'reverse', 'italic', 'strike')
Use a numeric ANSI 0-255 color instead of a made-up name
Catch the Error and fall back to the default color setting

Example fix

// before (config)
[color]
    ui = purpul bold
// after
[color]
    ui = brightred bold

Defensive patterns

Strategy: validation

Validate before calling

fn is_valid_git_color(s: &str) -> bool {
    let colors = ["normal","black","red","green","yellow","blue","magenta","cyan","white"];
    let attrs = ["bold","dim","ul","blink","reverse","italic","strike"];
    let mut toks = s.split_whitespace();
    let c = toks.next().unwrap_or("");
    (colors.iter().any(|x| c.eq_ignore_ascii_case(x)) || c.parse::<u8>().is_ok())
        && toks.all(|t| attrs.contains(&t))
}

Try / catch

let color = Color::try_from(value).unwrap_or_default();

Prevention

Only write color names from the git-documented set
Validate color config when accepting user input in tooling
Fall back to defaults instead of failing on exotic color strings

When it happens

Trigger: `Color::try_from(&BStr)` or `Color::from_str` with input like 'redd', 'purplish', 'bright' alone, or an attribute spelled wrong ('bald' instead of 'bold').

Common situations: Hand-edited `[color]` sections in `.git/config`, e.g. `ui = purpul bold`, or scripts writing color values without validating against git's accepted names.

Understand the failure class

Background: "Invalid value" and "allowed values are" config errors: what your library rejected and how to fix it — this error's family across 41 libraries.

Related errors

AI-assisted analysis of GitoxideLabs/gitoxide@e73179060b (2026-09-08). Data as JSON: /api/errors/5244eb182a09fcea. Report an issue: GitHub.

Appendix: source

Thrown at gix-config-value/src/color.rs:34

            if write_space.take().is_some() {
                write!(f, " ")?;
            }
            bg.fmt(f)?;
            write_space = Some(());
        }

        if !self.attributes.is_empty() {
            if write_space.take().is_some() {
                write!(f, " ")?;
            }
            self.attributes.fmt(f)?;
        }
        Ok(())
    }
}

fn color_err(input: impl Into<BString>) -> Error {
    Error::new(
        "Colors are specific color values and their attributes, like 'brightred', or 'blue'",
        input,
    )
}

impl TryFrom<&BStr> for Color {
    type Error = Error;

    fn try_from(s: &BStr) -> Result<Self, Self::Error> {
        let s = std::str::from_utf8(s).map_err(|err| color_err(s).with_err(err))?;
        enum ColorItem {
            Value(Name),
            Attr(Attribute),
        }

        let items = s.split_whitespace().filter_map(|s| {
            if s.is_empty() {
                return None;

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