perf: use simd-json for package.json parsing (#761)

## Summary

Replace `serde_json` with `simd-json` using `BorrowedValue` for zero-copy JSON parsing. Uses `self_cell` to manage the self-referential structure where the parsed JSON borrows from the original string.

Breaking change:

* raw API with `package_json_raw_json_api` feature is removed.
* Returned error no longer has line and column information.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Author: Boshen

Cargo.lock

@@ -83,8 +83,11 @@ json-strip-comments = "3"
 once_cell = "1" # Use `std::sync::OnceLock::get_or_try_init` when it is stable.
 papaya = "0.2"
 rustc-hash = { version = "2" }
+self_cell = "1"
 serde = { version = "1", features = ["derive"] } # derive for Deserialize from package.json
 serde_json = { version = "1", features = ["preserve_order"] } # preserve_order: package_json.exports requires order such as `["require", "import", "default"]`
+# Omit serde_impl and swar-number-parsing (package.json seldom has floats).
+simd-json = { version = "0.17.0", default-features = false, features = ["runtime-detection"] }
 simdutf8 = { version = "0.1" }
 thiserror = "2"
 tracing = "0.1"
@@ -115,9 +118,6 @@ windows-sys = { version = "0.61.0", features = ["Win32_Storage", "Win32_Storage_
 
 [features]
 default = []
-## Enables the [PackageJson::raw_json] API,
-## which returns the `package.json` with `serde_json::Value`.
-package_json_raw_json_api = []
 ## [Yarn Plug'n'Play](https://yarnpkg.com/features/pnp)
 yarn_pnp = ["pnp"]
 # For codspeed benchmark

Cargo.toml

@@ -283,33 +283,24 @@ fn bench_package_json_deserialization(c: &mut Criterion) {
     let test_path = PathBuf::from("/test/package.json");
     let test_realpath = test_path.clone();
 
-    group.bench_function("small", |b| {
-        b.iter(|| {
-            PackageJson::parse(test_path.clone(), test_realpath.clone(), small_json)
-                .expect("Failed to parse small JSON");
-        });
-    });
-
-    group.bench_function("medium", |b| {
-        b.iter(|| {
-            PackageJson::parse(test_path.clone(), test_realpath.clone(), medium_json)
-                .expect("Failed to parse medium JSON");
-        });
-    });
+    let data = [
+        ("small", small_json.to_string()),
+        ("medium", medium_json.to_string()),
+        ("large", large_json.to_string()),
+        ("complex_real", complex_json),
+    ];
 
-    group.bench_function("large", |b| {
-        b.iter(|| {
-            PackageJson::parse(test_path.clone(), test_realpath.clone(), large_json)
-                .expect("Failed to parse large JSON");
-        });
-    });
-
-    group.bench_function("complex_real", |b| {
-        b.iter(|| {
-            PackageJson::parse(test_path.clone(), test_realpath.clone(), &complex_json)
-                .expect("Failed to parse complex JSON");
+    for (name, json) in data {
+        group.bench_function(name, |b| {
+            b.iter_with_setup_wrapper(|runner| {
+                let json = json.clone();
+                runner.run(|| {
+                    PackageJson::parse(test_path.clone(), test_realpath.clone(), json)
+                        .expect("Failed to parse JSON");
+                });
+            });
         });
-    });
+    }
 
     group.finish();
 }

benches/resolver.rs

@@ -96,6 +96,7 @@ allow = [
   "Unicode-3.0",
   "BSD-2-Clause",
   "MPL-2.0",
+  "Zlib",
   # "Apache-2.0 WITH LLVM-exception",
 ]
 # The confidence threshold for detecting a license from license text.

deny.toml

@@ -120,9 +120,9 @@ impl<Fs: FileSystem> Cache<Fs> {
                 } else {
                     package_json_path.clone()
                 };
-                PackageJson::parse(package_json_path.clone(), real_path, &package_json_string)
+                PackageJson::parse(package_json_path.clone(), real_path, package_json_string)
                     .map(|package_json| Some(Arc::new(package_json)))
-                    .map_err(|error| ResolveError::from_serde_json_error(package_json_path, &error))
+                    .map_err(|error| ResolveError::from_simd_json_error(package_json_path, &error))
             })
             .cloned();
         // https://github.com/webpack/enhanced-resolve/blob/58464fc7cb56673c9aa849e68e6300239601e615/lib/DescriptionFileUtils.js#L68-L82

src/cache/cache_impl.rs

@@ -135,6 +135,17 @@ impl ResolveError {
             column: error.column(),
         })
     }
+
+    #[cold]
+    #[must_use]
+    pub fn from_simd_json_error(path: PathBuf, error: &simd_json::Error) -> Self {
+        Self::Json(JSONError {
+            path,
+            message: error.to_string(),
+            line: 0, // simd_json doesn't provide line/column info
+            column: 0,
+        })
+    }
 }
 
 /// Error for [ResolveError::Specifier]

src/error.rs

@@ -75,7 +75,7 @@ pub use crate::{
     },
     package_json::{
         ImportsExportsArray, ImportsExportsEntry, ImportsExportsKind, ImportsExportsMap,
-        PackageJson, PackageType,
+        PackageJson, PackageType, SideEffects,
     },
     path::PathUtil,
     resolution::{ModuleType, Resolution},