use std::process::Command;
fn main() {
println!("cargo:rerun-if-env-changed=MUM_VERSION");
let env_version = std::env::var("MUM_VERSION").ok();
let version = match env_version.or_else(commit_hash).as_deref() {
None | Some("") => format!("v{}", env!("CARGO_PKG_VERSION")),
Some(version) => version.to_string(),
};
println!("cargo:rustc-env=VERSION={}", version);
}
fn commit_hash() -> Option<String> {
let output = Command::new("git")
.arg("describe")
.arg("--tags")
.current_dir(env!("CARGO_MANIFEST_DIR"))
.output();
output
.ok()
.map(|o| String::from_utf8_lossy(&o.stdout).to_string())
}