refactor: implement AsRef<str> for ConstStorage

Author: morrisonlevi

profiling/benches/concatenation.rs

@@ -68,11 +68,7 @@ fn bench_concatenation_internal2(c: &mut Criterion) {
     c.bench_function("bench_concatenation_internal2", |b| {
         b.iter(|| {
             for _ in 1..=100 {
-                _ = std::hint::black_box(extract_function_name_v2(
-                    b"standard",
-                    b"",
-                    b"file",
-                ))
+                _ = std::hint::black_box(extract_function_name_v2(b"standard", b"", b"file"))
             }
         });
     });

profiling/src/well_known.rs

@@ -1,6 +1,5 @@
 use datadog_alloc::Global;
 use std::borrow::Cow;
-use std::ops::Deref;
 
 use datadog_thin_str::{ConstStorage, ThinString};
 
@@ -44,45 +43,45 @@ pub enum WellKnown {
 
 impl From<WellKnown> for Cow<'static, str> {
     fn from(well_known: WellKnown) -> Self {
-        let storage: &'static _ = match well_known {
-            WellKnown::Empty => inline_strings::EMPTY.as_storage(),
-
-            WellKnown::BracketedEval => inline_strings::BRACKETED_EVAL.as_storage(),
-            WellKnown::BracketedFatal => inline_strings::BRACKETED_FATAL.as_storage(),
-            WellKnown::BracketedGc => inline_strings::BRACKETED_GC.as_storage(),
-            WellKnown::BracketedIdle => inline_strings::BRACKETED_IDLE.as_storage(),
-            WellKnown::BracketedInclude => inline_strings::BRACKETED_INCLUDE.as_storage(),
-            WellKnown::BracketedRequire => inline_strings::BRACKETED_REQUIRE.as_storage(),
-            WellKnown::BracketedSelect => inline_strings::BRACKETED_SELECT.as_storage(),
-            WellKnown::BracketedSleeping => inline_strings::BRACKETED_SLEEPING.as_storage(),
-            WellKnown::BracketedTruncated => inline_strings::BRACKETED_TRUNCATED.as_storage(),
+        let str: &'static str = match well_known {
+            WellKnown::Empty => inline_strings::EMPTY.as_ref(),
+
+            WellKnown::BracketedEval => inline_strings::BRACKETED_EVAL.as_ref(),
+            WellKnown::BracketedFatal => inline_strings::BRACKETED_FATAL.as_ref(),
+            WellKnown::BracketedGc => inline_strings::BRACKETED_GC.as_ref(),
+            WellKnown::BracketedIdle => inline_strings::BRACKETED_IDLE.as_ref(),
+            WellKnown::BracketedInclude => inline_strings::BRACKETED_INCLUDE.as_ref(),
+            WellKnown::BracketedRequire => inline_strings::BRACKETED_REQUIRE.as_ref(),
+            WellKnown::BracketedSelect => inline_strings::BRACKETED_SELECT.as_ref(),
+            WellKnown::BracketedSleeping => inline_strings::BRACKETED_SLEEPING.as_ref(),
+            WellKnown::BracketedTruncated => inline_strings::BRACKETED_TRUNCATED.as_ref(),
             WellKnown::BracketedUnknownIncludeType => {
-                inline_strings::BRACKETED_UNKNOWN_INCLUDE_TYPE.as_storage()
+                inline_strings::BRACKETED_UNKNOWN_INCLUDE_TYPE.as_ref()
             }
 
-            WellKnown::Compilation => inline_strings::COMPILATION.as_storage(),
-            WellKnown::Engine => inline_strings::ENGINE.as_storage(),
-            WellKnown::Fatal => inline_strings::FATAL.as_storage(),
-            WellKnown::Idle => inline_strings::IDLE.as_storage(),
-            WellKnown::Include => inline_strings::INCLUDE.as_storage(),
-            WellKnown::Induced => inline_strings::INDUCED.as_storage(),
-            WellKnown::OpcacheRestart => inline_strings::OPCACHE_RESTART.as_storage(),
-            WellKnown::PhpOpenTag => inline_strings::PHP_OPEN_TAG.as_storage(),
-            WellKnown::Require => inline_strings::REQUIRE.as_storage(),
-            WellKnown::Select => inline_strings::SELECT.as_storage(),
-            WellKnown::Sleeping => inline_strings::SLEEPING.as_storage(),
-            WellKnown::Unknown => inline_strings::UNKNOWN.as_storage(),
+            WellKnown::Compilation => inline_strings::COMPILATION.as_ref(),
+            WellKnown::Engine => inline_strings::ENGINE.as_ref(),
+            WellKnown::Fatal => inline_strings::FATAL.as_ref(),
+            WellKnown::Idle => inline_strings::IDLE.as_ref(),
+            WellKnown::Include => inline_strings::INCLUDE.as_ref(),
+            WellKnown::Induced => inline_strings::INDUCED.as_ref(),
+            WellKnown::OpcacheRestart => inline_strings::OPCACHE_RESTART.as_ref(),
+            WellKnown::PhpOpenTag => inline_strings::PHP_OPEN_TAG.as_ref(),
+            WellKnown::Require => inline_strings::REQUIRE.as_ref(),
+            WellKnown::Select => inline_strings::SELECT.as_ref(),
+            WellKnown::Sleeping => inline_strings::SLEEPING.as_ref(),
+            WellKnown::Unknown => inline_strings::UNKNOWN.as_ref(),
 
             #[cfg(php_zts)]
-            WellKnown::BracketedThreadStart => inline_strings::BRACKETED_THREAD_START.as_storage(),
+            WellKnown::BracketedThreadStart => inline_strings::BRACKETED_THREAD_START.as_ref(),
             #[cfg(php_zts)]
-            WellKnown::BracketedThreadStop => inline_strings::BRACKETED_THREAD_STOP.as_storage(),
+            WellKnown::BracketedThreadStop => inline_strings::BRACKETED_THREAD_STOP.as_ref(),
             #[cfg(php_zts)]
-            WellKnown::ThreadStart => inline_strings::THREAD_START.as_storage(),
+            WellKnown::ThreadStart => inline_strings::THREAD_START.as_ref(),
             #[cfg(php_zts)]
-            WellKnown::ThreadStop => inline_strings::THREAD_STOP.as_storage(),
+            WellKnown::ThreadStop => inline_strings::THREAD_STOP.as_ref(),
         };
-        Cow::Borrowed(storage.deref())
+        Cow::Borrowed(str)
     }
 }
 

thin-str/src/lib.rs

@@ -123,3 +123,10 @@ impl<const N: usize> ConstStorage<N> {
         unsafe { Storage::from_header(header_ptr) }
     }
 }
+
+impl<const N: usize> AsRef<str> for ConstStorage<N> {
+    fn as_ref(&self) -> &str {
+        // SAFETY: ConstStorage always hold valid strings.
+        unsafe { core::str::from_utf8_unchecked(&self.data) }
+    }
+}