From f2129e4f94d771c5c996210df6c1b4a25cffed6c Mon Sep 17 00:00:00 2001
From: David Sherret <dsherret@users.noreply.github.com>
Date: Thu, 3 Jul 2025 12:59:29 -0400
Subject: [PATCH] perf: bust emit cache only on deno_ast version change
 (#29984)

The emit cache is pretty stable nowadays, so we could probably just
cache bust whenever the deno_ast version changes instead of the CLI
version. This will also allow stuff like deno-js-loader to reuse cached
emits.
---
 Cargo.lock                  |  4 ++--
 Cargo.toml                  |  2 +-
 cli/factory.rs              |  3 ---
 cli/lsp/config.rs           |  4 ----
 libs/resolver/cache/emit.rs | 11 ++++-------
 libs/resolver/factory.rs    |  8 ++++----
 6 files changed, 11 insertions(+), 21 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index af8f74524e..824d2c12cd 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1636,9 +1636,9 @@ dependencies = [
 
 [[package]]
 name = "deno_ast"
-version = "0.48.0"
+version = "0.48.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0f883bd8eae4dfc8019d925ec3dd04b634b6af9346a5168acc259d55f5f5021d"
+checksum = "0ced09fdb8884e29716cc0691e8510f9c655762bbb9da3111dacc0a2ef6e8960"
 dependencies = [
  "base64 0.22.1",
  "capacity_builder",
diff --git a/Cargo.toml b/Cargo.toml
index 63826e2b91..be34aa5076 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -58,7 +58,7 @@ license = "MIT"
 repository = "https://github.com/denoland/deno"
 
 [workspace.dependencies]
-deno_ast = { version = "=0.48.0", features = ["transpiling"] }
+deno_ast = { version = "=0.48.1", features = ["transpiling"] }
 deno_core = { version = "0.352.0" }
 
 deno_cache_dir = "=0.23.0"
diff --git a/cli/factory.rs b/cli/factory.rs
index e7fb7dd953..ddfdd72e63 100644
--- a/cli/factory.rs
+++ b/cli/factory.rs
@@ -1220,9 +1220,6 @@ fn new_workspace_factory_options(
       }
       ConfigFlag::Disabled => ConfigDiscoveryOption::Disabled,
     },
-    emit_cache_version: Cow::Borrowed(
-      deno_lib::version::DENO_VERSION_INFO.deno,
-    ),
     maybe_custom_deno_dir_root: flags.internal.cache_path.clone(),
     // For `deno install/add/remove/init` we want to force the managed
     // resolver so it can set up the `node_modules/` directory.
diff --git a/cli/lsp/config.rs b/cli/lsp/config.rs
index ca7b3a54bb..acde81130e 100644
--- a/cli/lsp/config.rs
+++ b/cli/lsp/config.rs
@@ -1,6 +1,5 @@
 // Copyright 2018-2025 the Deno authors. MIT license.
 
-use std::borrow::Cow;
 use std::collections::BTreeMap;
 use std::collections::BTreeSet;
 use std::collections::HashMap;
@@ -1478,9 +1477,6 @@ impl ConfigData {
         config_discovery: ConfigDiscoveryOption::DiscoverCwd,
         maybe_custom_deno_dir_root: None,
         is_package_manager_subcommand: false,
-        emit_cache_version: Cow::Borrowed(
-          deno_lib::version::DENO_VERSION_INFO.deno,
-        ),
         frozen_lockfile: None,
         lock_arg: None,
         lockfile_skip_write: false,
diff --git a/libs/resolver/cache/emit.rs b/libs/resolver/cache/emit.rs
index 2ed3241f28..e1e618f8b7 100644
--- a/libs/resolver/cache/emit.rs
+++ b/libs/resolver/cache/emit.rs
@@ -40,13 +40,10 @@ impl<TSys: EmitCacheSys> EmitCache<TSys> {
     disk_cache: DiskCache<TSys>,
     cache_version: Cow<'static, str>,
   ) -> Self {
-    let mode = match sys
-      .env_var("DENO_EMIT_CACHE_MODE")
-      .unwrap_or_default()
-      .as_str()
-    {
-      "normal" | "" => Mode::Normal,
-      "disable" => Mode::Disable,
+    let emit_cache_mode = sys.env_var_os("DENO_EMIT_CACHE_MODE");
+    let mode = match emit_cache_mode.as_ref().and_then(|s| s.to_str()) {
+      Some("normal") | Some("") | None => Mode::Normal,
+      Some("disable") => Mode::Disable,
       _ => {
         log::warn!("Unknown DENO_EMIT_CACHE_MODE value, defaulting to normal");
         Mode::Normal
diff --git a/libs/resolver/factory.rs b/libs/resolver/factory.rs
index f7a69657aa..190a6e4809 100644
--- a/libs/resolver/factory.rs
+++ b/libs/resolver/factory.rs
@@ -198,9 +198,6 @@ pub struct WorkspaceFactoryOptions {
   pub additional_config_file_names: &'static [&'static str],
   pub config_discovery: ConfigDiscoveryOption,
   pub is_package_manager_subcommand: bool,
-  /// Version to use for the emit cache. This is something that
-  /// should change when the version of the underlying emit changes.
-  pub emit_cache_version: Cow<'static, str>,
   pub frozen_lockfile: Option<bool>,
   pub lock_arg: Option<String>,
   /// Whether to skip writing to the lockfile.
@@ -301,7 +298,10 @@ impl<TSys: WorkspaceFactorySys> WorkspaceFactory<TSys> {
       Ok(new_rc(EmitCache::new(
         &self.sys,
         self.deno_dir()?.gen_cache.clone(),
-        self.options.emit_cache_version.clone(),
+        #[cfg(feature = "deno_ast")]
+        Cow::Borrowed(deno_ast::VERSION),
+        #[cfg(not(feature = "deno_ast"))]
+        Cow::Borrowed(env!("CARGO_PKG_VERSION")),
       )))
     })
   }