From 99fb39734e8acb45c862f3254d05b3f931cdfd3f Mon Sep 17 00:00:00 2001
From: Boshen <boshenc@gmail.com>
Date: Thu, 27 Jun 2024 23:53:55 +0800
Subject: [PATCH] perf: omit searching for package.json when `alias_fields` is
 not provided

---
 src/lib.rs                              | 14 +++++++++-----
 src/tests/incorrect_description_file.rs |  7 +++++--
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index 40c51359..f1fe36ce 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -647,11 +647,15 @@ impl<Fs: FileSystem> ResolverGeneric<Fs> {
     }
 
     fn load_alias_or_file(&self, cached_path: &CachedPath, ctx: &mut Ctx) -> ResolveResult {
-        if let Some(package_json) =
-            cached_path.find_package_json(&self.cache.fs, &self.options, ctx)?
-        {
-            if let Some(path) = self.load_browser_field(cached_path, None, &package_json, ctx)? {
-                return Ok(Some(path));
+        if !self.options.alias_fields.is_empty() {
+            if let Some(package_json) =
+                cached_path.find_package_json(&self.cache.fs, &self.options, ctx)?
+            {
+                if let Some(path) =
+                    self.load_browser_field(cached_path, None, &package_json, ctx)?
+                {
+                    return Ok(Some(path));
+                }
             }
         }
         // enhanced-resolve: try file as alias
diff --git a/src/tests/incorrect_description_file.rs b/src/tests/incorrect_description_file.rs
index a5c81796..e2caecbb 100644
--- a/src/tests/incorrect_description_file.rs
+++ b/src/tests/incorrect_description_file.rs
@@ -17,8 +17,11 @@ fn incorrect_description_file_1() {
         column: 0,
     });
     assert_eq!(resolution, Err(error));
-    assert_eq!(ctx.file_dependencies, FxHashSet::from_iter([f.join("pack1/package.json")]));
-    assert!(ctx.missing_dependencies.is_empty());
+    assert_eq!(
+        ctx.file_dependencies,
+        FxHashSet::from_iter([f.join("pack1"), f.join("pack1/package.json")])
+    );
+    assert!(!ctx.missing_dependencies.is_empty());
 }
 
 // should not resolve main in incorrect description file #2