Auto merge of #80790 - JohnTitor:rollup-js1noez, r=JohnTitor

Rollup of 10 pull requests

Successful merges:

 - #80012 (Add pointing const identifier when emitting E0435)
 - #80521 (MIR Inline is incompatible with coverage)
 - #80659 (Edit rustc_ast::tokenstream docs)
 - #80660 (Properly handle primitive disambiguators in rustdoc)
 - #80738 (Remove bottom margin from crate version when the docs sidebar is collapsed)
 - #80744 (rustdoc: Turn `next_def_id` comments into docs)
 - #80750 (Don't use to_string on Symbol in rustc_passes/check_attr.rs)
 - #80769 (Improve wording of parse doc)
 - #80780 (Return EOF_CHAR constant instead of magic char.)
 - #80784 (rustc_parse: Better spans for synthesized token streams)

Failed merges:

 - #80785 (rustc_ast_pretty: Remove `PrintState::insert_extra_parens`)

r? `@ghost`
`@rustbot` modify labels: rollup

diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs
index 58bf74c8cf470252308a050b50d673e9ba334c2d..bd01271ec150ff0944f41953e67a7fa1bfe83f67 100644 (file)
--- a/library/core/src/slice/mod.rs
+++ b/library/core/src/slice/mod.rs
@@ -1872,19 +1872,24 @@ pub fn ends_with(&self, needle: &[T]) -> bool
     /// # Examples
     ///
     /// ```
-    /// #![feature(slice_strip)]
     /// let v = &[10, 40, 30];
     /// assert_eq!(v.strip_prefix(&[10]), Some(&[40, 30][..]));
     /// assert_eq!(v.strip_prefix(&[10, 40]), Some(&[30][..]));
     /// assert_eq!(v.strip_prefix(&[50]), None);
     /// assert_eq!(v.strip_prefix(&[10, 50]), None);
+    ///
+    /// let prefix : &str = "he";
+    /// assert_eq!(b"hello".strip_prefix(prefix.as_bytes()),
+    ///            Some(b"llo".as_ref()));
     /// ```
     #[must_use = "returns the subslice without modifying the original"]
-    #[unstable(feature = "slice_strip", issue = "73413")]
-    pub fn strip_prefix(&self, prefix: &[T]) -> Option<&[T]>
+    #[stable(feature = "slice_strip", since = "1.50.0")]
+    pub fn strip_prefix<P: SlicePattern<Item = T> + ?Sized>(&self, prefix: &P) -> Option<&[T]>
     where
         T: PartialEq,
     {
+        // This function will need rewriting if and when SlicePattern becomes more sophisticated.
+        let prefix = prefix.as_slice();
         let n = prefix.len();
         if n <= self.len() {
             let (head, tail) = self.split_at(n);
@@ -1905,7 +1910,6 @@ pub fn strip_prefix(&self, prefix: &[T]) -> Option<&[T]>
     /// # Examples
     ///
     /// ```
-    /// #![feature(slice_strip)]
     /// let v = &[10, 40, 30];
     /// assert_eq!(v.strip_suffix(&[30]), Some(&[10, 40][..]));
     /// assert_eq!(v.strip_suffix(&[40, 30]), Some(&[10][..]));
@@ -1913,11 +1917,13 @@ pub fn strip_prefix(&self, prefix: &[T]) -> Option<&[T]>
     /// assert_eq!(v.strip_suffix(&[50, 30]), None);
     /// ```
     #[must_use = "returns the subslice without modifying the original"]
-    #[unstable(feature = "slice_strip", issue = "73413")]
-    pub fn strip_suffix(&self, suffix: &[T]) -> Option<&[T]>
+    #[stable(feature = "slice_strip", since = "1.50.0")]
+    pub fn strip_suffix<P: SlicePattern<Item = T> + ?Sized>(&self, suffix: &P) -> Option<&[T]>
     where
         T: PartialEq,
     {
+        // This function will need rewriting if and when SlicePattern becomes more sophisticated.
+        let suffix = suffix.as_slice();
         let (len, n) = (self.len(), suffix.len());
         if n <= len {
             let (head, tail) = self.split_at(len - n);
@@ -3310,3 +3316,35 @@ fn default() -> Self {
         &mut []
     }
 }
+
+#[unstable(feature = "slice_pattern", reason = "stopgap trait for slice patterns", issue = "56345")]
+/// Patterns in slices - currently, only used by `strip_prefix` and `strip_suffix`.  At a future
+/// point, we hope to generalise `core::str::Pattern` (which at the time of writing is limited to
+/// `str`) to slices, and then this trait will be replaced or abolished.
+pub trait SlicePattern {
+    /// The element type of the slice being matched on.
+    type Item;
+
+    /// Currently, the consumers of `SlicePattern` need a slice.
+    fn as_slice(&self) -> &[Self::Item];
+}
+
+#[stable(feature = "slice_strip", since = "1.50.0")]
+impl<T> SlicePattern for [T] {
+    type Item = T;
+
+    #[inline]
+    fn as_slice(&self) -> &[Self::Item] {
+        self
+    }
+}
+
+#[stable(feature = "slice_strip", since = "1.50.0")]
+impl<T, const N: usize> SlicePattern for [T; N] {
+    type Item = T;
+
+    #[inline]
+    fn as_slice(&self) -> &[Self::Item] {
+        self
+    }
+}

diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index 2c6f03fe2240688caeaf7f4b82adc91cec668779..15ef5d1619ba33cd8f458a028795e7ceef85368e 100644 (file)
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -307,7 +307,6 @@
 #![feature(slice_internals)]
 #![feature(slice_ptr_get)]
 #![feature(slice_ptr_len)]
-#![feature(slice_strip)]
 #![feature(staged_api)]
 #![feature(std_internals)]
 #![feature(stdsimd)]