fix(compiler): compile race condition in browser

compiler/src/lib.rs

@@ -42,6 +42,7 @@ pub mod world;
 
 /// Diff and parse the source code.
 mod parser;
+mod utils;
 
 /// Convenient services over [`world::CompilerWorld`].
 pub mod service;

compiler/src/utils.rs

@@ -0,0 +1,22 @@
+#[cfg(all(target_arch = "wasm32", target_os = "unknown"))]
+#[allow(unused_macros)]
+macro_rules! console_log {
+    ($($arg:tt)*) => {
+        web_sys::console::info_1(&format!(
+            $($arg)*
+        ).into());
+    }
+}
+
+#[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
+#[allow(unused_macros)]
+macro_rules! console_log {
+    ($($arg:tt)*) => {
+        println!(
+            $($arg)*
+        );
+    }
+}
+
+#[allow(unused_imports)]
+pub(crate) use console_log;

compiler/src/vfs/overlay.rs

@@ -10,7 +10,7 @@ use crate::time::SystemTime;
 
 use super::AccessModel;
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 struct OverlayFileMeta {
     mt: SystemTime,
     content: Bytes,
@@ -52,7 +52,27 @@ impl<M: AccessModel> OverlayAccessModel<M> {
 
         let mt = SystemTime::now();
         let meta = OverlayFileMeta { mt, content };
-        self.files.write().insert(path, meta);
+        self.files
+            .write()
+            .entry(path)
+            .and_modify(|e| {
+                // unlikely to happen but still possible in concurrent
+                // environment
+                // The case is found in browser test
+                if e.mt == meta.mt && e.content != meta.content {
+                    e.mt = meta
+                        .mt
+                        // instant::SystemTime has a minimum resolution of 1ms
+                        // we negate the time by 1ms so that the time is always
+                        // invalidated
+                        .checked_sub(std::time::Duration::from_millis(1))
+                        .unwrap();
+                    e.content = meta.content.clone();
+                } else {
+                    *e = meta.clone();
+                }
+            })
+            .or_insert(meta);
     }
 
     pub fn remove_file(&self, path: &Path) {

compiler/src/vfs/trace.rs

@@ -41,7 +41,7 @@ impl<M: AccessModel + Sized, C: Clone> TraceAccessModel<CachedAccessModel<M, C>>
             elapsed.as_nanos() as u64,
             std::sync::atomic::Ordering::Relaxed,
         );
-        println!("read_all_diff: {:?} {:?}", src, elapsed);
+        crate::utils::console_log!("read_all_diff: {:?} {:?}", src, elapsed);
         res
     }
 }
@@ -60,7 +60,7 @@ impl<M: AccessModel + Sized> AccessModel for TraceAccessModel<M> {
             elapsed.as_nanos() as u64,
             std::sync::atomic::Ordering::Relaxed,
         );
-        println!("mtime: {:?} {:?}", src, elapsed);
+        crate::utils::console_log!("mtime: {:?} {:?} => {:?}", src, elapsed, res);
         res
     }
 
@@ -72,7 +72,7 @@ impl<M: AccessModel + Sized> AccessModel for TraceAccessModel<M> {
             elapsed.as_nanos() as u64,
             std::sync::atomic::Ordering::Relaxed,
         );
-        println!("is_file: {:?} {:?}", src, elapsed);
+        crate::utils::console_log!("is_file: {:?} {:?}", src, elapsed);
         res
     }
 
@@ -84,7 +84,7 @@ impl<M: AccessModel + Sized> AccessModel for TraceAccessModel<M> {
             elapsed.as_nanos() as u64,
             std::sync::atomic::Ordering::Relaxed,
         );
-        println!("real_path: {:?} {:?}", src, elapsed);
+        crate::utils::console_log!("real_path: {:?} {:?}", src, elapsed);
         res
     }
 
@@ -96,7 +96,7 @@ impl<M: AccessModel + Sized> AccessModel for TraceAccessModel<M> {
             elapsed.as_nanos() as u64,
             std::sync::atomic::Ordering::Relaxed,
         );
-        println!("read_all: {:?} {:?}", src, elapsed);
+        crate::utils::console_log!("read_all: {:?} {:?}", src, elapsed);
         res
     }