From 020c5d74706754981c14f35d50ac48034bd00fd9 Mon Sep 17 00:00:00 2001
From: Nico Burns <nico@nicoburns.com>
Date: Sun, 30 Apr 2023 11:54:11 +0100
Subject: [PATCH 1/3] Encapsulate unsafe in _cssparser_internal_to_lowercase
 macro

This allows it to be used in codebases with #[forbid(unsafe)].
Also document the safety invariant for the unsafe block
---
 src/macros.rs | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/macros.rs b/src/macros.rs
index 1dfacbb5..69b5801b 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -121,11 +121,19 @@ macro_rules! ascii_case_insensitive_phf_map {
 #[doc(hidden)]
 macro_rules! _cssparser_internal_to_lowercase {
     ($input: expr, $BUFFER_SIZE: expr => $output: ident) => {
-        #[allow(unsafe_code)]
-        let mut buffer = unsafe {
-            ::std::mem::MaybeUninit::<[::std::mem::MaybeUninit<u8>; $BUFFER_SIZE]>::uninit()
-                .assume_init()
-        };
+        /// Create a new array of MaybeUninit<T> items, in an uninitialized state.
+        #[inline(always)]
+        fn create_uninit_array<const N: usize>() -> [::std::mem::MaybeUninit<u8>; N] {
+            unsafe {
+                // SAFETY: An uninitialized `[MaybeUninit<_>; LEN]` is valid.
+                // See: https://doc.rust-lang.org/stable/core/mem/union.MaybeUninit.html#method.uninit_array
+                ::std::mem::MaybeUninit::<[::std::mem::MaybeUninit<u8>; N]>::uninit()
+                    .assume_init()
+            }
+        }
+
+        const BUFFER_SIZE: usize = $BUFFER_SIZE as usize;
+        let mut buffer = create_uninit_array::<BUFFER_SIZE>();
         let input: &str = $input;
         let $output = $crate::_cssparser_internal_to_lowercase(&mut buffer, input);
     };

From 8982f0be11b6a05e93b5348282fd69623c861a27 Mon Sep 17 00:00:00 2001
From: Nico Burns <nico@nicoburns.com>
Date: Sun, 30 Apr 2023 12:06:43 +0100
Subject: [PATCH 2/3] Move function outside of macro definition

---
 src/macros.rs | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/src/macros.rs b/src/macros.rs
index 69b5801b..34aa0e27 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -110,6 +110,16 @@ macro_rules! ascii_case_insensitive_phf_map {
     }
 }
 
+/// Create a new array of MaybeUninit<T> items, in an uninitialized state.
+#[inline(always)]
+pub fn _cssparser_internal_create_uninit_array<const N: usize>() -> [MaybeUninit<u8>; N] {
+    unsafe {
+        // SAFETY: An uninitialized `[MaybeUninit<_>; LEN]` is valid.
+        // See: https://doc.rust-lang.org/stable/core/mem/union.MaybeUninit.html#method.uninit_array
+        MaybeUninit::<[MaybeUninit<u8>; N]>::uninit().assume_init()
+    }
+}
+
 /// Implementation detail of match_ignore_ascii_case! and ascii_case_insensitive_phf_map! macros.
 ///
 /// **This macro is not part of the public API. It can change or be removed between any versions.**
@@ -121,19 +131,8 @@ macro_rules! ascii_case_insensitive_phf_map {
 #[doc(hidden)]
 macro_rules! _cssparser_internal_to_lowercase {
     ($input: expr, $BUFFER_SIZE: expr => $output: ident) => {
-        /// Create a new array of MaybeUninit<T> items, in an uninitialized state.
-        #[inline(always)]
-        fn create_uninit_array<const N: usize>() -> [::std::mem::MaybeUninit<u8>; N] {
-            unsafe {
-                // SAFETY: An uninitialized `[MaybeUninit<_>; LEN]` is valid.
-                // See: https://doc.rust-lang.org/stable/core/mem/union.MaybeUninit.html#method.uninit_array
-                ::std::mem::MaybeUninit::<[::std::mem::MaybeUninit<u8>; N]>::uninit()
-                    .assume_init()
-            }
-        }
-
         const BUFFER_SIZE: usize = $BUFFER_SIZE as usize;
-        let mut buffer = create_uninit_array::<BUFFER_SIZE>();
+        let mut buffer = $crate::macros::_cssparser_internal_create_uninit_array::<BUFFER_SIZE>();
         let input: &str = $input;
         let $output = $crate::_cssparser_internal_to_lowercase(&mut buffer, input);
     };

From 39ea1b07a899e76ed2bb3e311c39992f79f0baab Mon Sep 17 00:00:00 2001
From: Nico Burns <nico@nicoburns.com>
Date: Sun, 30 Apr 2023 12:10:47 +0100
Subject: [PATCH 3/3] Fix fn reference and remove usize cast

---
 src/lib.rs    | 4 +++-
 src/macros.rs | 3 +--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index 2c580a61..bac46221 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -75,7 +75,9 @@ pub use crate::color::{
 pub use crate::cow_rc_str::CowRcStr;
 pub use crate::from_bytes::{stylesheet_encoding, EncodingSupport};
 #[doc(hidden)]
-pub use crate::macros::_cssparser_internal_to_lowercase;
+pub use crate::macros::{
+    _cssparser_internal_create_uninit_array, _cssparser_internal_to_lowercase,
+};
 pub use crate::nth::parse_nth;
 pub use crate::parser::{BasicParseError, BasicParseErrorKind, ParseError, ParseErrorKind};
 pub use crate::parser::{Delimiter, Delimiters, Parser, ParserInput, ParserState};
diff --git a/src/macros.rs b/src/macros.rs
index 34aa0e27..882b0bbc 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -131,8 +131,7 @@ pub fn _cssparser_internal_create_uninit_array<const N: usize>() -> [MaybeUninit
 #[doc(hidden)]
 macro_rules! _cssparser_internal_to_lowercase {
     ($input: expr, $BUFFER_SIZE: expr => $output: ident) => {
-        const BUFFER_SIZE: usize = $BUFFER_SIZE as usize;
-        let mut buffer = $crate::macros::_cssparser_internal_create_uninit_array::<BUFFER_SIZE>();
+        let mut buffer = $crate::_cssparser_internal_create_uninit_array::<{ $BUFFER_SIZE }>();
         let input: &str = $input;
         let $output = $crate::_cssparser_internal_to_lowercase(&mut buffer, input);
     };