Fix issue with glob pattern

src/app.rs

@@ -283,6 +283,8 @@ fn build(mode: &Option<String>) -> std::io::Result<()> {
 
     child.wait()?;
 
+    std::fs::write(format!("target/{}/.build_hash", build_config.name), hash)?;
+
     let stop = start.elapsed();
 
     println!(
@@ -298,7 +300,7 @@ fn build(mode: &Option<String>) -> std::io::Result<()> {
 
 fn hash_src_tree() -> std::io::Result<String> {
     let mut hashes = String::new();
-    for entry in glob("src/").expect("a valid glob pattern") {
+    for entry in glob("src/**/*").expect("a valid glob pattern") {
         if let Ok(file) = entry {
             let text = std::fs::read_to_string(file)?;
             let hash = sha256::digest(text);