Add latest_stable_rust feature (#203)

* add the feature

* missing_inline

* const version of try_from_array_len, and some missing inlines

Author: Lokathor

.github/workflows/rust.yml

@@ -34,7 +34,7 @@ jobs:
     - name: Test non nightly
       if: matrix.rust != '1.47.0' && matrix.rust != 'nightly'
       run: |
-        cargo test --features=alloc,std,grab_spare_slice
+        cargo test --features=alloc,std,grab_spare_slice,latest_stable_rust
     - name: Test on Nightly with All Features
       if: matrix.rust == 'nightly'
       run: |

Cargo.toml

@@ -47,6 +47,11 @@ rustc_1_57 = ["rustc_1_55"]
 # add retain_mut function to TinyVec
 rustc_1_61 = ["rustc_1_57"]
 
+# We're done with per-version featuring, this feature opts in to all the
+# abilities of the latest release of Stable rust, and we don't need a million
+# features forever now.
+latest_stable_rust = ["rustc_1_61"]
+
 # allow use of nightly feature `slice_partition_dedup`,
 # will become useless once that is stabilized:
 # https://github.com/rust-lang/rust/issues/54279
@@ -69,11 +74,11 @@ experimental_write_impl = []
 real_blackbox = ["criterion/real_blackbox"]
 
 [package.metadata.docs.rs]
-features = ["alloc", "std", "grab_spare_slice", "rustc_1_55", "serde"]
-rustdoc-args = ["--cfg","docs_rs"]
+features = ["alloc", "std", "grab_spare_slice", "latest_stable_rust", "serde"]
+rustdoc-args = ["--cfg", "docs_rs"]
 
 [package.metadata.playground]
-features = ["alloc", "std", "grab_spare_slice", "rustc_1_55", "serde"]
+features = ["alloc", "std", "grab_spare_slice", "latest_stable_rust", "serde"]
 
 [profile.bench]
 debug = 2

src/arrayvec.rs

@@ -1071,6 +1071,7 @@ impl<A: Array> ArrayVec<A> {
   /// If the given length is greater than the capacity of the array this will
   /// error, and you'll get the array back in the `Err`.
   #[inline]
+  #[cfg(not(feature = "latest_stable_rust"))]
   pub fn try_from_array_len(data: A, len: usize) -> Result<Self, A> {
     /* Note(Soveu): Should we allow A::CAPACITY > u16::MAX for now? */
     if len <= A::CAPACITY {
@@ -1079,6 +1080,26 @@ impl<A: Array> ArrayVec<A> {
       Err(data)
     }
   }
+
+  /// Wraps an array, using the given length as the starting length.
+  ///
+  /// If you want to use the whole length of the array, you can just use the
+  /// `From` impl.
+  ///
+  /// ## Failure
+  ///
+  /// If the given length is greater than the capacity of the array this will
+  /// error, and you'll get the array back in the `Err`.
+  #[inline]
+  #[cfg(feature = "latest_stable_rust")]
+  pub const fn try_from_array_len(data: A, len: usize) -> Result<Self, A> {
+    /* Note(Soveu): Should we allow A::CAPACITY > u16::MAX for now? */
+    if len <= A::CAPACITY {
+      Ok(Self { data, len: len as u16 })
+    } else {
+      Err(data)
+    }
+  }
 }
 
 impl<A> ArrayVec<A> {
@@ -1883,6 +1904,7 @@ impl<A: Array> ArrayVec<A> {
   /// assert_eq!(v, &[1, 2, 3]);
   /// assert_eq!(v.capacity(), 13);
   /// ```
+  #[inline]
   #[cfg(feature = "rustc_1_57")]
   pub fn try_drain_to_vec_and_reserve(
     &mut self, n: usize,
@@ -1925,6 +1947,7 @@ impl<A: Array> ArrayVec<A> {
   /// // Vec may reserve more than necessary in order to prevent more future allocations.
   /// assert!(v.capacity() >= 3);
   /// ```
+  #[inline]
   #[cfg(feature = "rustc_1_57")]
   pub fn try_drain_to_vec(&mut self) -> Result<Vec<A::Item>, TryReserveError> {
     self.try_drain_to_vec_and_reserve(0)

src/tinyvec.rs

@@ -316,6 +316,7 @@ impl<A: Array> TinyVec<A> {
   /// assert_eq!(Ok(()), tv.try_move_to_the_heap());
   /// assert!(tv.is_heap());
   /// ```
+  #[inline]
   #[cfg(feature = "rustc_1_57")]
   pub fn try_move_to_the_heap(&mut self) -> Result<(), TryReserveError> {
     let arr = match self {
@@ -364,6 +365,7 @@ impl<A: Array> TinyVec<A> {
   /// assert!(tv.is_heap());
   /// assert!(tv.capacity() >= 35);
   /// ```
+  #[inline]
   #[cfg(feature = "rustc_1_57")]
   pub fn try_move_to_the_heap_and_reserve(
     &mut self, n: usize,
@@ -419,6 +421,7 @@ impl<A: Array> TinyVec<A> {
   /// assert!(tv.is_heap());
   /// assert!(tv.capacity() >= 5);
   /// ```
+  #[inline]
   #[cfg(feature = "rustc_1_57")]
   pub fn try_reserve(&mut self, n: usize) -> Result<(), TryReserveError> {
     let arr = match self {
@@ -489,6 +492,7 @@ impl<A: Array> TinyVec<A> {
   /// assert!(tv.is_heap());
   /// assert!(tv.capacity() >= 5);
   /// ```
+  #[inline]
   #[cfg(feature = "rustc_1_57")]
   pub fn try_reserve_exact(&mut self, n: usize) -> Result<(), TryReserveError> {
     let arr = match self {