build.rs

use std::process::Command;

fn main() {
    let sha = Command::new("git")
        .args(["rev-parse", "--short=7", "HEAD"])
        .output()
        .ok()
        .and_then(|o| {
            o.status
                .success()
                .then(|| String::from_utf8(o.stdout).ok())
                .flatten()
        })
        .map(|s| s.trim().to_string())
        .unwrap_or_else(|| "unknown".to_string());

    let dirty = Command::new("git")
        .args(["status", "--porcelain"])
        .output()
        .map(|o| !o.stdout.is_empty())
        .unwrap_or(false);

    let suffix = if dirty && sha != "unknown" {
        format!("{sha}-dirty")
    } else {
        sha
    };
    println!("cargo:rustc-env=UTTER_GIT_SHA={suffix}");
    println!("cargo:rerun-if-changed=.git/HEAD");
    println!("cargo:rerun-if-changed=.git/index");
    println!("cargo:rerun-if-changed=build.rs");
}