//! Low level terminal capability lookups#![cfg_attr(docsrs, feature(doc_cfg))]#![warn(missing_docs)]#![warn(clippy::print_stderr)]#![warn(clippy::print_stdout)]pub mod windows;/// Check [CLICOLOR] status////// - When `true`, ANSI colors are supported and should be used when the program isn't piped,///   similar to [`term_supports_color`]/// - When `false`, don’t output ANSI color escape codes, similar to [`no_color`]////// See also:/// - [terminfo](https://crates.io/crates/terminfo) or [term](https://crates.io/crates/term) for///   checking termcaps/// - [termbg](https://crates.io/crates/termbg) for detecting background color////// [CLICOLOR]: https://bixense.com/clicolors/#[inline]pub fn clicolor() -> Option<bool> {    let value = std::env::var_os("CLICOLOR")?;    Some(value != "0")}/// Check [CLICOLOR_FORCE] status////// ANSI colors should be enabled no matter what.////// [CLICOLOR_FORCE]: https://bixense.com/clicolors/#[inline]pub fn clicolor_force() -> bool {    non_empty(std::env::var_os("CLICOLOR_FORCE").as_deref())}/// Check [NO_COLOR] status////// When `true`, should prevent the addition of ANSI color.////// User-level configuration files and per-instance command-line arguments should override/// [NO_COLOR]. A user should be able to export `$NO_COLOR` in their shell configuration file as a/// default, but configure a specific program in its configuration file to specifically enable/// color.////// [NO_COLOR]: https://no-color.org/#[inline]pub fn no_color() -> bool {    non_empty(std::env::var_os("NO_COLOR").as_deref())}/// Check `TERM` for color support#[inline]pub fn term_supports_color() -> bool {    #[cfg(not(windows))]    {        match std::env::var_os("TERM") {            // If TERM isn't set, then we are in a weird environment that            // probably doesn't support colors.            None => return false,            Some(k) => {                if k == "dumb" {                    return false;                }            }        }        true    }    #[cfg(windows)]    {        // On Windows, if TERM isn't set, then we shouldn't automatically        // assume that colors aren't allowed. This is unlike Unix environments        // where TERM is more rigorously set.        if let Some(k) = std::env::var_os("TERM") {            if k == "dumb" {                return false;            }        }        true    }}/// Check `TERM` for ANSI color support////// On Windows, you might need to also check [`windows::enable_ansi_colors`] as ANSI color support/// is opt-in, rather than assumed.#[inline]pub fn term_supports_ansi_color() -> bool {    #[cfg(not(windows))]    {        term_supports_color()    }    #[cfg(windows)]    {        match std::env::var_os("TERM") {            None => return false,            Some(k) => {                // cygwin doesn't seem to support ANSI escape sequences                // and instead has its own variety. However, the Windows                // console API may be available.                if k == "dumb" || k == "cygwin" {                    return false;                }            }        }        true    }}/// Check [COLORTERM] for truecolor support////// [COLORTERM]: https://github.com/termstandard/colors#[inline]pub fn truecolor() -> bool {    let value = std::env::var_os("COLORTERM");    let value = value.as_deref().unwrap_or_default();    value == "truecolor" || value == "24bit"}/// Report whether this is running in CI////// CI is a common environment where, despite being piped, ansi color codes are supported////// This is not as exhaustive as you'd find in a crate like `is_ci` but it should work in enough/// cases.#[inline]pub fn is_ci() -> bool {    // Assuming its CI based on presence because who would be setting `CI=false`?    //    // This makes it easier to all of the potential values when considering our known values:    // - Gitlab and Github set it to `true`    // - Woodpecker sets it to `woodpecker`    std::env::var_os("CI").is_some()}fn non_empty(var: Option<&std::ffi::OsStr>) -> bool {    !var.unwrap_or_default().is_empty()}#[cfg(test)]mod test {    use super::*;    #[test]    fn non_empty_not_present() {        assert!(!non_empty(None));    }    #[test]    fn non_empty_empty() {        assert!(!non_empty(Some(std::ffi::OsStr::new(""))));    }    #[test]    fn non_empty_texty() {        assert!(non_empty(Some(std::ffi::OsStr::new("hello"))));    }}#[doc = include_str!("../README.md")]#[cfg(doctest)]pub struct ReadmeDoctests;