From c549b19df37ee2e82ab7ca06014b33fa52413a0f Mon Sep 17 00:00:00 2001
From: Divy Srivastava <dj.srivastava23@gmail.com>
Date: Tue, 20 Sep 2022 17:55:15 +0530
Subject: [PATCH] fastcall: Fix `get_storage_if_aligned` for non-uint8arrays
 (#1077)

---
 src/fast_api.rs   | 12 ++++--------
 tests/test_api.rs |  2 +-
 2 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/src/fast_api.rs b/src/fast_api.rs
index a7894e1b..6fa3872e 100644
--- a/src/fast_api.rs
+++ b/src/fast_api.rs
@@ -192,7 +192,8 @@ pub struct FastApiCallbackOptions<'a> {
 // https://source.chromium.org/chromium/chromium/src/+/main:v8/include/v8-fast-api-calls.h;l=336
 #[repr(C)]
 pub struct FastApiTypedArray<T: Default> {
-  pub byte_length: usize,
+  /// Returns the length in number of elements.
+  pub length: usize,
   // This pointer should include the typed array offset applied.
   // It's not guaranteed that it's aligned to sizeof(T), it's only
   // guaranteed that it's 4-byte aligned, so for 8-byte types we need to
@@ -204,7 +205,7 @@ pub struct FastApiTypedArray<T: Default> {
 impl<T: Default> FastApiTypedArray<T> {
   #[inline]
   pub fn get(&self, index: usize) -> T {
-    debug_assert!(index < self.byte_length);
+    debug_assert!(index < self.length);
     let mut t: T = Default::default();
     unsafe {
       ptr::copy_nonoverlapping(self.data.add(index), &mut t, 1);
@@ -217,12 +218,7 @@ impl<T: Default> FastApiTypedArray<T> {
     if (self.data as usize) % align_of::<T>() != 0 {
       return None;
     }
-    Some(unsafe {
-      std::slice::from_raw_parts_mut(
-        self.data,
-        self.byte_length / align_of::<T>(),
-      )
-    })
+    Some(unsafe { std::slice::from_raw_parts_mut(self.data, self.length) })
   }
 }
 
diff --git a/tests/test_api.rs b/tests/test_api.rs
index db60360e..7a1a8e71 100644
--- a/tests/test_api.rs
+++ b/tests/test_api.rs
@@ -7560,7 +7560,7 @@ fn test_fast_calls_overload() {
   ) {
     unsafe { WHO = "fast_buf" };
     let buf = unsafe { &*data };
-    assert_eq!(buf.byte_length, 2);
+    assert_eq!(buf.length, 2);
     assert_eq!(buf.get(0), 6);
     assert_eq!(buf.get(1), 9);
   }