add git branch and commit to version information

build.rs

@@ -0,0 +1,15 @@
+use std::process::Command;
+
+fn main() {
+    // get
+    let output = Command::new("git").args(&["rev-parse", "--short", "HEAD"]).output()
+        .expect("git rev-parse HEAD failed");
+    let hash = String::from_utf8(output.stdout).expect("not UTF-8 output");
+
+    let output = Command::new("git").args(&["rev-parse", "--abbrev-ref", "HEAD"]).output()
+        .expect("git rev-parse HEAD failed");
+    let branch = String::from_utf8(output.stdout).expect("not UTF-8 output");
+
+    println!("cargo:rustc-env=GIT_HASH={}", hash);
+    println!("cargo:rustc-env=GIT_BRANCH={}", branch);
+}

src/lib.rs

@@ -184,7 +184,11 @@ impl<'a, R: BufRead> Runtime<'a, R> {
             globals: HashMap::from([
                 ("version'".into(), Arc::new(
                     Mutex::new(
-                        Object::value(Value::String(env!("CARGO_PKG_VERSION").into()), HashMap::new(), HashMap::new()))))
+                        Object::value(Value::String(
+                            format!("{} ({}/{})",
+                                    env!("CARGO_PKG_VERSION"),
+                                    env!("GIT_BRANCH"),
+                                    env!("GIT_HASH"))), HashMap::new(), HashMap::new()))))
             ]),
             parser: None,
         }