Implement `Debug` for `EncodeWide`
Since `std::os::windows::ffi::EncodeWide` was reexported from
`std::sys_common::wtf8::EncodeWide`, which has
`#![allow(missing_debug_implementations)]` in the parent module, it did
not implement `Debug`. When it was moved to `core`, a placeholder impl
was added; fill it in.
diff --git a/library/alloc/src/wtf8/tests.rs b/library/alloc/src/wtf8/tests.rs
index 291f63f..a72ad08 100644
--- a/library/alloc/src/wtf8/tests.rs
+++ b/library/alloc/src/wtf8/tests.rs
@@ -580,6 +580,17 @@ fn wtf8_encode_wide_size_hint() {
}
#[test]
+fn wtf8_encode_wide_debug() {
+ let mut string = Wtf8Buf::from_str("aé ");
+ string.push(CodePoint::from_u32(0xD83D).unwrap());
+ string.push_char('💩');
+ assert_eq!(
+ format!("{:?}", string.encode_wide()),
+ r#"EncodeWide(['a', 'é', ' ', 0xD83D, 0xD83D, 0xDCA9])"#
+ );
+}
+
+#[test]
fn wtf8_clone_into() {
let mut string = Wtf8Buf::new();
clone_into(Wtf8::from_str("green"), &mut string);
diff --git a/library/core/src/wtf8.rs b/library/core/src/wtf8.rs
index de0dfa5..0c03496 100644
--- a/library/core/src/wtf8.rs
+++ b/library/core/src/wtf8.rs
@@ -562,15 +562,36 @@ fn size_hint(&self) -> (usize, Option<usize>) {
}
}
-impl fmt::Debug for EncodeWide<'_> {
- fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
- f.debug_struct("EncodeWide").finish_non_exhaustive()
- }
-}
-
#[stable(feature = "encode_wide_fused_iterator", since = "1.62.0")]
impl FusedIterator for EncodeWide<'_> {}
+#[stable(feature = "encode_wide_debug", since = "CURRENT_RUSTC_VERSION")]
+impl fmt::Debug for EncodeWide<'_> {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ struct CodeUnit(u16);
+ impl fmt::Debug for CodeUnit {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ // This output attempts to balance readability with precision.
+ // Render characters which take only one WTF-16 code unit using
+ // `char` syntax and everything else as code units with hex
+ // integer syntax (including paired and unpaired surrogate
+ // halves). Since Rust has no `char`-like type for WTF-16, this
+ // isn't perfect, so if this output isn't suitable, it is open
+ // to being changed (see #140153).
+ match char::from_u32(self.0 as u32) {
+ Some(c) => write!(f, "{c:?}"),
+ None => write!(f, "0x{:04X}", self.0),
+ }
+ }
+ }
+
+ write!(f, "EncodeWide(")?;
+ f.debug_list().entries(self.clone().map(CodeUnit)).finish()?;
+ write!(f, ")")?;
+ Ok(())
+ }
+}
+
impl Hash for CodePoint {
#[inline]
fn hash<H: Hasher>(&self, state: &mut H) {
diff --git a/library/std/src/sys_common/mod.rs b/library/std/src/sys_common/mod.rs
index ec45c72..c6cb1b0 100644
--- a/library/std/src/sys_common/mod.rs
+++ b/library/std/src/sys_common/mod.rs
@@ -15,7 +15,6 @@
//! Progress on this is tracked in #84187.
#![allow(missing_docs)]
-#![allow(missing_debug_implementations)]
#[cfg(test)]
mod tests;
