perf: skip saving to emit cache after first failure (#24896)

cli/cache/emit.rs

@@ -6,6 +6,7 @@ use deno_ast::ModuleSpecifier;
 use deno_core::anyhow::anyhow;
 use deno_core::error::AnyError;
 use deno_core::serde_json;
+use deno_core::unsync::sync::AtomicFlag;
 use serde::Deserialize;
 use serde::Serialize;
 
@@ -19,10 +20,10 @@ struct EmitMetadata {
 }
 
 /// The cache that stores previously emitted files.
-#[derive(Clone)]
 pub struct EmitCache {
   disk_cache: DiskCache,
   cli_version: &'static str,
+  emit_failed_flag: AtomicFlag,
 }
 
 impl EmitCache {
@@ -30,6 +31,7 @@ impl EmitCache {
     Self {
       disk_cache,
       cli_version: crate::version::deno(),
+      emit_failed_flag: Default::default(),
     }
   }
 
@@ -87,12 +89,10 @@ impl EmitCache {
     code: &[u8],
   ) {
     if let Err(err) = self.set_emit_code_result(specifier, source_hash, code) {
-      // should never error here, but if it ever does don't fail
-      if cfg!(debug_assertions) {
-        panic!("Error saving emit data ({specifier}): {err}");
-      } else {
+      // might error in cases such as a readonly file system
       log::debug!("Error saving emit data ({}): {}", specifier, err);
-      }
+      // assume the cache can't be written to and disable caching to it
+      self.emit_failed_flag.raise();
     }
   }
 
@@ -102,6 +102,11 @@ impl EmitCache {
     source_hash: u64,
     code: &[u8],
   ) -> Result<(), AnyError> {
+    if self.emit_failed_flag.is_raised() {
+      log::debug!("Skipped emit cache save of {}", specifier);
+      return Ok(());
+    }
+
     let meta_filename = self
       .get_meta_filename(specifier)
       .ok_or_else(|| anyhow!("Could not get meta filename."))?;
@@ -161,6 +166,7 @@ mod test {
     let cache = EmitCache {
       disk_cache: disk_cache.clone(),
       cli_version: "1.0.0",
+      emit_failed_flag: Default::default(),
     };
     let to_string =
       |bytes: Vec<u8>| -> String { String::from_utf8(bytes).unwrap() };
@@ -192,6 +198,7 @@ mod test {
     let cache = EmitCache {
       disk_cache: disk_cache.clone(),
       cli_version: "2.0.0",
+      emit_failed_flag: Default::default(),
     };
     assert_eq!(cache.get_emit_code(&specifier1, 10), None);
     cache.set_emit_code(&specifier1, 5, emit_code1.as_bytes());
@@ -200,6 +207,7 @@ mod test {
     let cache = EmitCache {
       disk_cache,
       cli_version: "2.0.0",
+      emit_failed_flag: Default::default(),
     };
     assert_eq!(
       cache.get_emit_code(&specifier1, 5).map(to_string),

cli/cache/mod.rs

@@ -106,7 +106,7 @@ pub use deno_cache_dir::HttpCache;
 /// A "wrapper" for the FileFetcher and DiskCache for the Deno CLI that provides
 /// a concise interface to the DENO_DIR when building module graphs.
 pub struct FetchCacher {
-  emit_cache: EmitCache,
+  emit_cache: Arc<EmitCache>,
   file_fetcher: Arc<FileFetcher>,
   file_header_overrides: HashMap<ModuleSpecifier, HashMap<String, String>>,
   global_http_cache: Arc<GlobalHttpCache>,
@@ -118,7 +118,7 @@ pub struct FetchCacher {
 
 impl FetchCacher {
   pub fn new(
-    emit_cache: EmitCache,
+    emit_cache: Arc<EmitCache>,
     file_fetcher: Arc<FileFetcher>,
     file_header_overrides: HashMap<ModuleSpecifier, HashMap<String, String>>,
     global_http_cache: Arc<GlobalHttpCache>,

cli/emit.rs

@@ -18,7 +18,7 @@ use deno_graph::ModuleGraph;
 use std::sync::Arc;
 
 pub struct Emitter {
-  emit_cache: EmitCache,
+  emit_cache: Arc<EmitCache>,
   parsed_source_cache: Arc<ParsedSourceCache>,
   transpile_and_emit_options:
     Arc<(deno_ast::TranspileOptions, deno_ast::EmitOptions)>,
@@ -28,7 +28,7 @@ pub struct Emitter {
 
 impl Emitter {
   pub fn new(
-    emit_cache: EmitCache,
+    emit_cache: Arc<EmitCache>,
     parsed_source_cache: Arc<ParsedSourceCache>,
     transpile_options: deno_ast::TranspileOptions,
     emit_options: deno_ast::EmitOptions,

cli/factory.rs

@@ -164,7 +164,7 @@ struct CliFactoryServices {
   global_http_cache: Deferred<Arc<GlobalHttpCache>>,
   http_cache: Deferred<Arc<dyn HttpCache>>,
   http_client_provider: Deferred<Arc<HttpClientProvider>>,
-  emit_cache: Deferred<EmitCache>,
+  emit_cache: Deferred<Arc<EmitCache>>,
   emitter: Deferred<Arc<Emitter>>,
   fs: Deferred<Arc<dyn deno_fs::FileSystem>>,
   main_graph_container: Deferred<Arc<MainModuleGraphContainer>>,
@@ -492,9 +492,9 @@ impl CliFactory {
       .get_or_init(|| maybe_file_watcher_reporter)
   }
 
-  pub fn emit_cache(&self) -> Result<&EmitCache, AnyError> {
+  pub fn emit_cache(&self) -> Result<&Arc<EmitCache>, AnyError> {
     self.services.emit_cache.get_or_try_init(|| {
-      Ok(EmitCache::new(self.deno_dir()?.gen_cache.clone()))
+      Ok(Arc::new(EmitCache::new(self.deno_dir()?.gen_cache.clone())))
     })
   }
 

cli/graph_util.rs

@@ -364,7 +364,7 @@ pub struct ModuleGraphBuilder {
   parsed_source_cache: Arc<ParsedSourceCache>,
   lockfile: Option<Arc<CliLockfile>>,
   maybe_file_watcher_reporter: Option<FileWatcherReporter>,
-  emit_cache: cache::EmitCache,
+  emit_cache: Arc<cache::EmitCache>,
   file_fetcher: Arc<FileFetcher>,
   global_http_cache: Arc<GlobalHttpCache>,
 }
@@ -381,7 +381,7 @@ impl ModuleGraphBuilder {
     parsed_source_cache: Arc<ParsedSourceCache>,
     lockfile: Option<Arc<CliLockfile>>,
     maybe_file_watcher_reporter: Option<FileWatcherReporter>,
-    emit_cache: cache::EmitCache,
+    emit_cache: Arc<cache::EmitCache>,
     file_fetcher: Arc<FileFetcher>,
     global_http_cache: Arc<GlobalHttpCache>,
   ) -> Self {

tests/integration/run_tests.rs

@@ -5342,3 +5342,20 @@ async fn listen_tls_alpn_fail() {
   let status = child.wait().unwrap();
   assert!(status.success());
 }
+
+// Couldn't get the directory readonly on windows on the CI
+// so gave up because this being tested on unix is good enough
+#[cfg(unix)]
+#[test]
+fn emit_failed_readonly_file_system() {
+  let context = TestContextBuilder::default().use_temp_cwd().build();
+  context.deno_dir().path().canonicalize().make_dir_readonly();
+  let temp_dir = context.temp_dir().path().canonicalize();
+  temp_dir.join("main.ts").write("import './other.ts';");
+  temp_dir.join("other.ts").write("console.log('hi');");
+  let output = context
+    .new_command()
+    .args("run --log-level=debug main.ts")
+    .run();
+  output.assert_matches_text("[WILDCARD]Error saving emit data ([WILDLINE]main.ts)[WILDCARD]Skipped emit cache save of [WILDLINE]other.ts[WILDCARD]hi[WILDCARD]");
+}