Auto merge of #72286 - Dylan-DPC:rollup-n3rk6df, r=Dylan-DPC

Rollup of 4 pull requests

Successful merges:

 - #72233 (Fix {:#?} representation of proc_macro::Literal)
 - #72277 (emphasize that ManuallyDrop is safe-to-access and unsafe-to-drop)
 - #72281 (Fix whitespace in `?Sized` structured suggestion)
 - #72282 (Fix issue number typo in note)

Failed merges:

r? @ghost

Author: bors

src/libcore/mem/manually_drop.rs

@@ -2,7 +2,6 @@ use crate::ops::{Deref, DerefMut};
 use crate::ptr;
 
 /// A wrapper to inhibit compiler from automatically calling `T`’s destructor.
-///
 /// This wrapper is 0-cost.
 ///
 /// `ManuallyDrop<T>` is subject to the same layout optimizations as `T`.
@@ -11,6 +10,11 @@ use crate::ptr;
 /// with [`mem::zeroed`] is undefined behavior.
 /// If you need to handle uninitialized data, use [`MaybeUninit<T>`] instead.
 ///
+/// Note that accessing the value inside a `ManuallyDrop<T>` is safe.
+/// This means that a `ManuallyDrop<T>` whose content has been dropped must not
+/// be exposed through a public safe API.
+/// Correspondingly, `ManuallyDrop::drop` is unsafe.
+///
 /// # Examples
 ///
 /// This wrapper can be used to enforce a particular drop order on fields, regardless

src/libproc_macro/bridge/client.rs

@@ -202,10 +202,16 @@ impl Clone for Literal {
     }
 }
 
-// FIXME(eddyb) `Literal` should not expose internal `Debug` impls.
 impl fmt::Debug for Literal {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.write_str(&self.debug())
+        f.debug_struct("Literal")
+            // format the kind without quotes, as in `kind: Float`
+            .field("kind", &format_args!("{}", &self.debug_kind()))
+            .field("symbol", &self.symbol())
+            // format `Some("...")` on one line even in {:#?} mode
+            .field("suffix", &format_args!("{:?}", &self.suffix()))
+            .field("span", &self.span())
+            .finish()
     }
 }
 

src/libproc_macro/bridge/mod.rs

@@ -103,8 +103,9 @@ macro_rules! with_api {
             Literal {
                 fn drop($self: $S::Literal);
                 fn clone($self: &$S::Literal) -> $S::Literal;
-                // FIXME(eddyb) `Literal` should not expose internal `Debug` impls.
-                fn debug($self: &$S::Literal) -> String;
+                fn debug_kind($self: &$S::Literal) -> String;
+                fn symbol($self: &$S::Literal) -> String;
+                fn suffix($self: &$S::Literal) -> Option<String>;
                 fn integer(n: &str) -> $S::Literal;
                 fn typed_integer(n: &str, kind: &str) -> $S::Literal;
                 fn float(n: &str) -> $S::Literal;

src/libproc_macro/lib.rs

@@ -1141,7 +1141,6 @@ impl fmt::Display for Literal {
 #[stable(feature = "proc_macro_lib2", since = "1.29.0")]
 impl fmt::Debug for Literal {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        // FIXME(eddyb) `Literal` should not expose internal `Debug` impls.
         self.0.fmt(f)
     }
 }

src/librustc_expand/proc_macro_server.rs

@@ -507,9 +507,14 @@ impl server::Ident for Rustc<'_> {
 }
 
 impl server::Literal for Rustc<'_> {
-    // FIXME(eddyb) `Literal` should not expose internal `Debug` impls.
-    fn debug(&mut self, literal: &Self::Literal) -> String {
-        format!("{:?}", literal)
+    fn debug_kind(&mut self, literal: &Self::Literal) -> String {
+        format!("{:?}", literal.lit.kind)
+    }
+    fn symbol(&mut self, literal: &Self::Literal) -> String {
+        literal.lit.symbol.to_string()
+    }
+    fn suffix(&mut self, literal: &Self::Literal) -> Option<String> {
+        literal.lit.suffix.as_ref().map(Symbol::to_string)
     }
     fn integer(&mut self, n: &str) -> Self::Literal {
         self.lit(token::Integer, Symbol::intern(n), None)

src/librustc_trait_selection/traits/error_reporting/mod.rs

@@ -1655,7 +1655,7 @@ impl<'a, 'tcx> InferCtxtPrivExt<'tcx> for InferCtxt<'a, 'tcx> {
                     {
                         let (span, separator) = match param.bounds {
                             [] => (span.shrink_to_hi(), ":"),
-                            [.., bound] => (bound.span().shrink_to_hi(), " + "),
+                            [.., bound] => (bound.span().shrink_to_hi(), " +"),
                         };
                         err.span_suggestion_verbose(
                             span,

src/librustc_trait_selection/traits/error_reporting/suggestions.rs

@@ -1685,7 +1685,7 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
                 if suggest_const_in_array_repeat_expressions {
                     err.note(
                         "this array initializer can be evaluated at compile-time, see issue \
-                         #48147 <https://github.com/rust-lang/rust/issues/49147> \
+                         #49147 <https://github.com/rust-lang/rust/issues/49147> \
                          for more information",
                     );
                     if tcx.sess.opts.unstable_features.is_nightly_build() {

src/test/ui/feature-gates/feature-gate-const_in_array_repeat_expressions.stderr

@@ -7,7 +7,7 @@ LL |     let arr: [Option<String>; 2] = [None::<String>; 2];
    = help: the following implementations were found:
              <std::option::Option<T> as std::marker::Copy>
    = note: the `Copy` trait is required because the repeated element will be copied
-   = note: this array initializer can be evaluated at compile-time, see issue #48147 <https://github.com/rust-lang/rust/issues/49147> for more information
+   = note: this array initializer can be evaluated at compile-time, see issue #49147 <https://github.com/rust-lang/rust/issues/49147> for more information
    = help: add `#![feature(const_in_array_repeat_expressions)]` to the crate attributes to enable
 
 error[E0277]: the trait bound `std::option::Option<std::string::String>: std::marker::Copy` is not satisfied

src/test/ui/lint/redundant-semicolon/redundant-semi-proc-macro.stderr

@@ -1,4 +1,4 @@
-TokenStream [Ident { ident: "fn", span: #0 bytes(198..200) }, Ident { ident: "span_preservation", span: #0 bytes(201..218) }, Group { delimiter: Parenthesis, stream: TokenStream [], span: #0 bytes(218..220) }, Group { delimiter: Brace, stream: TokenStream [Ident { ident: "let", span: #0 bytes(228..231) }, Ident { ident: "tst", span: #0 bytes(232..235) }, Punct { ch: '=', spacing: Alone, span: #0 bytes(236..237) }, Literal { lit: Lit { kind: Integer, symbol: "123", suffix: None }, span: Span { lo: BytePos(238), hi: BytePos(241), ctxt: #0 } }, Punct { ch: ';', spacing: Joint, span: #0 bytes(241..242) }, Punct { ch: ';', spacing: Alone, span: #0 bytes(242..243) }, Ident { ident: "match", span: #0 bytes(289..294) }, Ident { ident: "tst", span: #0 bytes(295..298) }, Group { delimiter: Brace, stream: TokenStream [Literal { lit: Lit { kind: Integer, symbol: "123", suffix: None }, span: Span { lo: BytePos(483), hi: BytePos(486), ctxt: #0 } }, Punct { ch: '=', spacing: Joint, span: #0 bytes(487..489) }, Punct { ch: '>', spacing: Alone, span: #0 bytes(487..489) }, Group { delimiter: Parenthesis, stream: TokenStream [], span: #0 bytes(490..492) }, Punct { ch: ',', spacing: Alone, span: #0 bytes(492..493) }, Ident { ident: "_", span: #0 bytes(502..503) }, Punct { ch: '=', spacing: Joint, span: #0 bytes(504..506) }, Punct { ch: '>', spacing: Alone, span: #0 bytes(504..506) }, Group { delimiter: Parenthesis, stream: TokenStream [], span: #0 bytes(507..509) }], span: #0 bytes(299..515) }, Punct { ch: ';', spacing: Joint, span: #0 bytes(515..516) }, Punct { ch: ';', spacing: Joint, span: #0 bytes(516..517) }, Punct { ch: ';', spacing: Alone, span: #0 bytes(517..518) }], span: #0 bytes(222..562) }]
+TokenStream [Ident { ident: "fn", span: #0 bytes(198..200) }, Ident { ident: "span_preservation", span: #0 bytes(201..218) }, Group { delimiter: Parenthesis, stream: TokenStream [], span: #0 bytes(218..220) }, Group { delimiter: Brace, stream: TokenStream [Ident { ident: "let", span: #0 bytes(228..231) }, Ident { ident: "tst", span: #0 bytes(232..235) }, Punct { ch: '=', spacing: Alone, span: #0 bytes(236..237) }, Literal { kind: Integer, symbol: "123", suffix: None, span: #0 bytes(238..241) }, Punct { ch: ';', spacing: Joint, span: #0 bytes(241..242) }, Punct { ch: ';', spacing: Alone, span: #0 bytes(242..243) }, Ident { ident: "match", span: #0 bytes(289..294) }, Ident { ident: "tst", span: #0 bytes(295..298) }, Group { delimiter: Brace, stream: TokenStream [Literal { kind: Integer, symbol: "123", suffix: None, span: #0 bytes(483..486) }, Punct { ch: '=', spacing: Joint, span: #0 bytes(487..489) }, Punct { ch: '>', spacing: Alone, span: #0 bytes(487..489) }, Group { delimiter: Parenthesis, stream: TokenStream [], span: #0 bytes(490..492) }, Punct { ch: ',', spacing: Alone, span: #0 bytes(492..493) }, Ident { ident: "_", span: #0 bytes(502..503) }, Punct { ch: '=', spacing: Joint, span: #0 bytes(504..506) }, Punct { ch: '>', spacing: Alone, span: #0 bytes(504..506) }, Group { delimiter: Parenthesis, stream: TokenStream [], span: #0 bytes(507..509) }], span: #0 bytes(299..515) }, Punct { ch: ';', spacing: Joint, span: #0 bytes(515..516) }, Punct { ch: ';', spacing: Joint, span: #0 bytes(516..517) }, Punct { ch: ';', spacing: Alone, span: #0 bytes(517..518) }], span: #0 bytes(222..562) }]
 error: unnecessary trailing semicolon
   --> $DIR/redundant-semi-proc-macro.rs:9:19
    |

src/test/ui/proc-macro/debug/auxiliary/macro-dump-debug.rs

@@ -0,0 +1,15 @@
+// force-host
+// no-prefer-dynamic
+
+#![crate_type = "proc-macro"]
+#![crate_name = "macro_dump_debug"]
+
+extern crate proc_macro;
+use proc_macro::TokenStream;
+
+#[proc_macro]
+pub fn dump_debug(tokens: TokenStream) -> TokenStream {
+    eprintln!("{:?}", tokens);
+    eprintln!("{:#?}", tokens);
+    TokenStream::new()
+}