From f08175712dd42858f60c9a2e17f2acb15ea1cd4c Mon Sep 17 00:00:00 2001
From: overlookmotel <557937+overlookmotel@users.noreply.github.com>
Date: Tue, 20 May 2025 01:20:24 +0000
Subject: [PATCH] refactor(allocator/vec): simplify comparison macros (#11178)

Pure refactor. Simplify the macros which generate `PartialEq` impls for `Vec`, by removing repeated parts, removing unnecessary lifetimes, and renaming generic types to more conventional `T` and `U`, rather than `A` and `B`.
---
 crates/oxc_allocator/src/vec2/mod.rs | 36 +++++++++++++++-------------
 1 file changed, 20 insertions(+), 16 deletions(-)

diff --git a/crates/oxc_allocator/src/vec2/mod.rs b/crates/oxc_allocator/src/vec2/mod.rs
index 4c58693809f69..7ee38fdbaff2b 100644
--- a/crates/oxc_allocator/src/vec2/mod.rs
+++ b/crates/oxc_allocator/src/vec2/mod.rs
@@ -2363,14 +2363,15 @@ impl<'a, T: 'a + Copy> Extend<&'a T> for Vec<'_, T> {
     }
 }
 
+////////////////////////////////////////////////////////////////////////////////
+// Comparison
+////////////////////////////////////////////////////////////////////////////////
+
 macro_rules! __impl_slice_eq1 {
-    ($Lhs: ty, $Rhs: ty) => {
-        __impl_slice_eq1! { $Lhs, $Rhs, Sized }
-    };
-    ($Lhs: ty, $Rhs: ty, $Bound: ident) => {
-        impl<'a, 'b, A: $Bound, B> PartialEq<$Rhs> for $Lhs
+    ($Rhs: ty) => {
+        impl<T, U> PartialEq<$Rhs> for Vec<'_, T>
         where
-            A: PartialEq<B>,
+            T: PartialEq<U>,
         {
             #[inline]
             fn eq(&self, other: &$Rhs) -> bool {
@@ -2380,16 +2381,15 @@ macro_rules! __impl_slice_eq1 {
     };
 }
 
-__impl_slice_eq1! { Vec<'a, A>, Vec<'b, B> }
-__impl_slice_eq1! { Vec<'a, A>, &'b [B] }
-__impl_slice_eq1! { Vec<'a, A>, &'b mut [B] }
-// __impl_slice_eq1! { Cow<'a, [A]>, Vec<'b, B>, Clone }
+__impl_slice_eq1! { Vec<'_, U> }
+__impl_slice_eq1! { &[U] }
+__impl_slice_eq1! { &mut [U] }
 
 macro_rules! __impl_slice_eq1_array {
-    ($Lhs: ty, $Rhs: ty) => {
-        impl<'a, 'b, A, B, const N: usize> PartialEq<$Rhs> for $Lhs
+    ($Rhs: ty) => {
+        impl<T, U, const N: usize> PartialEq<$Rhs> for Vec<'_, T>
         where
-            A: PartialEq<B>,
+            T: PartialEq<U>,
         {
             #[inline]
             fn eq(&self, other: &$Rhs) -> bool {
@@ -2399,9 +2399,9 @@ macro_rules! __impl_slice_eq1_array {
     };
 }
 
-__impl_slice_eq1_array! { Vec<'a, A>, [B; N] }
-__impl_slice_eq1_array! { Vec<'a, A>, &'b [B; N] }
-__impl_slice_eq1_array! { Vec<'a, A>, &'b mut [B; N] }
+__impl_slice_eq1_array! { [U; N] }
+__impl_slice_eq1_array! { &[U; N] }
+__impl_slice_eq1_array! { &mut [U; N] }
 
 /// Implements comparison of vectors, lexicographically.
 impl<'a, T: 'a + PartialOrd> PartialOrd for Vec<'a, T> {
@@ -2421,6 +2421,10 @@ impl<'a, T: 'a + Ord> Ord for Vec<'a, T> {
     }
 }
 
+////////////////////////////////////////////////////////////////////////////////
+// Misc
+////////////////////////////////////////////////////////////////////////////////
+
 impl<'a, T: 'a + fmt::Debug> fmt::Debug for Vec<'a, T> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         fmt::Debug::fmt(&**self, f)