Add git hash to compiler versioning

Author: weirdsmiley

Cargo.toml

@@ -2,3 +2,4 @@
 name = "qcc"
 version = "0.1.0"
 edition = "2021"
+build = "build.rs"

build.rs

@@ -0,0 +1,16 @@
+use std::process::Command;
+use std::str;
+
+fn main() {
+    let revision = Command::new("git")
+        .args(&["rev-parse", "--short", "HEAD"])
+        .output()
+        .expect("failed to run git");
+
+    if revision.status.success() {
+        let hash = str::from_utf8(&revision.stdout).unwrap().trim();
+        println!("cargo:rustc-env=GIT_HASH={}", hash);
+    } else {
+        println!("cargo:rustc-env=GIT_HASH=unknown");
+    }
+}

src/config.rs

@@ -14,8 +14,9 @@ pub struct Config {
 }
 
 impl Config {
+    #[inline]
     fn version() -> &'static str {
-        env!("CARGO_PKG_VERSION") // + add latest commit hash
+        concat!(env!("CARGO_PKG_VERSION"), "+", env!("GIT_HASH"))
     }
 
     pub(crate) fn new() -> Self {

src/utils.rs

@@ -41,6 +41,7 @@ pub(crate) fn usage() {
     {:14}\t{:<20}
     {:14}\t{:<20}
     {:14}\t{:<20}
+    {:14}\t{:<20}
 ",
         "--help",
         "show this page",
@@ -61,7 +62,9 @@ pub(crate) fn usage() {
         "-d,--debug",
         "run compiler in debug-mode",
         "-o",
-        "compiled output"
+        "compiled output",
+        "-v,--version",
+        "compiler version"
     );
 }