Auto merge of rust-lang#83986 - Dylan-DPC:rollup-51vygcj, r=Dylan-DPC

Rollup of 5 pull requests

Successful merges:

 - rust-lang#82497 (Fix handling of `--output-format json` flag)
 - rust-lang#83689 (Add more info for common trait resolution and async/await errors)
 - rust-lang#83952 (Account for `ExprKind::Block` when suggesting .into() and deref)
 - rust-lang#83965 (Add Debug implementation for hir::intravisit::FnKind)
 - rust-lang#83974 (Fix outdated crate names in `rustc_interface::callbacks`)

Failed merges:

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

Author: bors

compiler/rustc_hir/src/intravisit.rs

@@ -98,7 +98,7 @@ where
     }
 }
 
-#[derive(Copy, Clone)]
+#[derive(Copy, Clone, Debug)]
 pub enum FnKind<'a> {
     /// `#[xxx] pub async/const/extern "Abi" fn foo()`
     ItemFn(Ident, &'a Generics<'a>, FnHeader, &'a Visibility<'a>),

compiler/rustc_interface/src/callbacks.rs

@@ -1,6 +1,6 @@
 //! Throughout the compiler tree, there are several places which want to have
 //! access to state or queries while being inside crates that are dependencies
-//! of librustc_middle. To facilitate this, we have the
+//! of `rustc_middle`. To facilitate this, we have the
 //! `rustc_data_structures::AtomicRef` type, which allows us to setup a global
 //! static which can then be set in this file at program startup.
 //!
@@ -13,8 +13,8 @@ use rustc_errors::{Diagnostic, TRACK_DIAGNOSTICS};
 use rustc_middle::ty::tls;
 use std::fmt;
 
-/// This is a callback from librustc_ast as it cannot access the implicit state
-/// in librustc_middle otherwise.
+/// This is a callback from `rustc_ast` as it cannot access the implicit state
+/// in `rustc_middle` otherwise.
 fn span_debug(span: rustc_span::Span, f: &mut fmt::Formatter<'_>) -> fmt::Result {
     tls::with_opt(|tcx| {
         if let Some(tcx) = tcx {
@@ -25,8 +25,8 @@ fn span_debug(span: rustc_span::Span, f: &mut fmt::Formatter<'_>) -> fmt::Result
     })
 }
 
-/// This is a callback from librustc_ast as it cannot access the implicit state
-/// in librustc_middle otherwise. It is used to when diagnostic messages are
+/// This is a callback from `rustc_ast` as it cannot access the implicit state
+/// in `rustc_middle` otherwise. It is used to when diagnostic messages are
 /// emitted and stores them in the current query, if there is one.
 fn track_diagnostic(diagnostic: &Diagnostic) {
     tls::with_context_opt(|icx| {
@@ -39,8 +39,8 @@ fn track_diagnostic(diagnostic: &Diagnostic) {
     })
 }
 
-/// This is a callback from librustc_hir as it cannot access the implicit state
-/// in librustc_middle otherwise.
+/// This is a callback from `rustc_hir` as it cannot access the implicit state
+/// in `rustc_middle` otherwise.
 fn def_id_debug(def_id: rustc_hir::def_id::DefId, f: &mut fmt::Formatter<'_>) -> fmt::Result {
     write!(f, "DefId({}:{}", def_id.krate, def_id.index.index())?;
     tls::with_opt(|opt_tcx| {

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -2070,7 +2070,14 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
 
                 // Don't print the tuple of capture types
                 if !is_upvar_tys_infer_tuple {
-                    err.note(&format!("required because it appears within the type `{}`", ty));
+                    let msg = format!("required because it appears within the type `{}`", ty);
+                    match ty.kind() {
+                        ty::Adt(def, _) => match self.tcx.opt_item_name(def.did) {
+                            Some(ident) => err.span_note(ident.span, &msg),
+                            None => err.note(&msg),
+                        },
+                        _ => err.note(&msg),
+                    };
                 }
 
                 obligated_types.push(ty);
@@ -2092,11 +2099,36 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
             ObligationCauseCode::ImplDerivedObligation(ref data) => {
                 let mut parent_trait_ref = self.resolve_vars_if_possible(data.parent_trait_ref);
                 let parent_def_id = parent_trait_ref.def_id();
-                err.note(&format!(
+                let msg = format!(
                     "required because of the requirements on the impl of `{}` for `{}`",
                     parent_trait_ref.print_only_trait_path(),
                     parent_trait_ref.skip_binder().self_ty()
-                ));
+                );
+                let mut candidates = vec![];
+                self.tcx.for_each_relevant_impl(
+                    parent_def_id,
+                    parent_trait_ref.self_ty().skip_binder(),
+                    |impl_def_id| {
+                        candidates.push(impl_def_id);
+                    },
+                );
+                match &candidates[..] {
+                    [def_id] => match self.tcx.hir().get_if_local(*def_id) {
+                        Some(Node::Item(hir::Item {
+                            kind: hir::ItemKind::Impl(hir::Impl { of_trait, self_ty, .. }),
+                            ..
+                        })) => {
+                            let mut spans = Vec::with_capacity(2);
+                            if let Some(trait_ref) = of_trait {
+                                spans.push(trait_ref.path.span);
+                            }
+                            spans.push(self_ty.span);
+                            err.span_note(spans, &msg)
+                        }
+                        _ => err.note(&msg),
+                    },
+                    _ => err.note(&msg),
+                };
 
                 let mut parent_predicate = parent_trait_ref.without_const().to_predicate(tcx);
                 let mut data = data;
@@ -2147,19 +2179,60 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
                     )
                 });
             }
-            ObligationCauseCode::CompareImplMethodObligation { .. } => {
-                err.note(&format!(
-                    "the requirement `{}` appears on the impl method but not on the corresponding \
-                     trait method",
-                    predicate
-                ));
+            ObligationCauseCode::CompareImplMethodObligation {
+                item_name,
+                trait_item_def_id,
+                ..
+            } => {
+                let msg = format!(
+                    "the requirement `{}` appears on the impl method `{}` but not on the \
+                     corresponding trait method",
+                    predicate, item_name,
+                );
+                let sp = self
+                    .tcx
+                    .opt_item_name(trait_item_def_id)
+                    .map(|i| i.span)
+                    .unwrap_or_else(|| self.tcx.def_span(trait_item_def_id));
+                let mut assoc_span: MultiSpan = sp.into();
+                assoc_span.push_span_label(
+                    sp,
+                    format!("this trait method doesn't have the requirement `{}`", predicate),
+                );
+                if let Some(ident) = self
+                    .tcx
+                    .opt_associated_item(trait_item_def_id)
+                    .and_then(|i| self.tcx.opt_item_name(i.container.id()))
+                {
+                    assoc_span.push_span_label(ident.span, "in this trait".into());
+                }
+                err.span_note(assoc_span, &msg);
             }
-            ObligationCauseCode::CompareImplTypeObligation { .. } => {
-                err.note(&format!(
-                    "the requirement `{}` appears on the associated impl type but not on the \
+            ObligationCauseCode::CompareImplTypeObligation {
+                item_name, trait_item_def_id, ..
+            } => {
+                let msg = format!(
+                    "the requirement `{}` appears on the associated impl type `{}` but not on the \
                      corresponding associated trait type",
-                    predicate
-                ));
+                    predicate, item_name,
+                );
+                let sp = self.tcx.def_span(trait_item_def_id);
+                let mut assoc_span: MultiSpan = sp.into();
+                assoc_span.push_span_label(
+                    sp,
+                    format!(
+                        "this trait associated type doesn't have the requirement `{}`",
+                        predicate,
+                    ),
+                );
+                if let Some(ident) = self
+                    .tcx
+                    .opt_associated_item(trait_item_def_id)
+                    .and_then(|i| self.tcx.opt_item_name(i.container.id()))
+                {
+                    assoc_span.push_span_label(ident.span, "in this trait".into());
+                }
+                err.span_note(assoc_span, &msg);
             }
             ObligationCauseCode::CompareImplConstObligation => {
                 err.note(&format!(

compiler/rustc_typeck/src/check/fn_ctxt/suggestions.rs

@@ -205,6 +205,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         found: Ty<'tcx>,
         expected_ty_expr: Option<&'tcx hir::Expr<'tcx>>,
     ) {
+        let expr = expr.peel_blocks();
         if let Some((sp, msg, suggestion, applicability)) = self.check_ref(expr, found, expected) {
             err.span_suggestion(sp, msg, suggestion, applicability);
         } else if let (ty::FnDef(def_id, ..), true) =

compiler/rustc_typeck/src/check/method/suggest.rs

@@ -987,59 +987,60 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     ) {
         let mut alt_rcvr_sugg = false;
         if let SelfSource::MethodCall(rcvr) = source {
-            info!(?span, ?item_name, ?rcvr_ty, ?rcvr);
-            if let ty::Adt(..) = rcvr_ty.kind() {
-                // Try alternative arbitrary self types that could fulfill this call.
-                // FIXME: probe for all types that *could* be arbitrary self-types, not
-                // just this list.
-                for (rcvr_ty, post) in &[
-                    (rcvr_ty, ""),
-                    (self.tcx.mk_mut_ref(&ty::ReErased, rcvr_ty), "&mut "),
-                    (self.tcx.mk_imm_ref(&ty::ReErased, rcvr_ty), "&"),
+            debug!(?span, ?item_name, ?rcvr_ty, ?rcvr);
+            // Try alternative arbitrary self types that could fulfill this call.
+            // FIXME: probe for all types that *could* be arbitrary self-types, not
+            // just this list.
+            for (rcvr_ty, post) in &[
+                (rcvr_ty, ""),
+                (self.tcx.mk_mut_ref(&ty::ReErased, rcvr_ty), "&mut "),
+                (self.tcx.mk_imm_ref(&ty::ReErased, rcvr_ty), "&"),
+            ] {
+                for (rcvr_ty, pre) in &[
+                    (self.tcx.mk_lang_item(rcvr_ty, LangItem::OwnedBox), "Box::new"),
+                    (self.tcx.mk_lang_item(rcvr_ty, LangItem::Pin), "Pin::new"),
+                    (self.tcx.mk_diagnostic_item(rcvr_ty, sym::Arc), "Arc::new"),
+                    (self.tcx.mk_diagnostic_item(rcvr_ty, sym::Rc), "Rc::new"),
                 ] {
-                    for (rcvr_ty, pre) in &[
-                        (self.tcx.mk_lang_item(rcvr_ty, LangItem::OwnedBox), "Box::new"),
-                        (self.tcx.mk_lang_item(rcvr_ty, LangItem::Pin), "Pin::new"),
-                        (self.tcx.mk_diagnostic_item(rcvr_ty, sym::Arc), "Arc::new"),
-                        (self.tcx.mk_diagnostic_item(rcvr_ty, sym::Rc), "Rc::new"),
-                    ] {
-                        if let Some(new_rcvr_t) = *rcvr_ty {
-                            if let Ok(pick) = self.lookup_probe(
-                                span,
-                                item_name,
-                                new_rcvr_t,
-                                rcvr,
-                                crate::check::method::probe::ProbeScope::AllTraits,
-                            ) {
-                                debug!("try_alt_rcvr: pick candidate {:?}", pick);
-                                // Make sure the method is defined for the *actual* receiver:
-                                // we don't want to treat `Box<Self>` as a receiver if
-                                // it only works because of an autoderef to `&self`
-                                if pick.autoderefs == 0
-                                    // We don't want to suggest a container type when the missing method is
-                                    // `.clone()`, otherwise we'd suggest `Arc::new(foo).clone()`, which is
-                                    // far from what the user really wants.
-                                    && Some(pick.item.container.id()) != self.tcx.lang_items().clone_trait()
-                                {
-                                    err.span_label(
-                                        pick.item.ident.span,
-                                        &format!(
-                                            "the method is available for `{}` here",
-                                            new_rcvr_t
-                                        ),
-                                    );
-                                    err.multipart_suggestion(
-                                        "consider wrapping the receiver expression with the \
-                                         appropriate type",
-                                        vec![
-                                            (rcvr.span.shrink_to_lo(), format!("{}({}", pre, post)),
-                                            (rcvr.span.shrink_to_hi(), ")".to_string()),
-                                        ],
-                                        Applicability::MaybeIncorrect,
-                                    );
-                                    // We don't care about the other suggestions.
-                                    alt_rcvr_sugg = true;
-                                }
+                    if let Some(new_rcvr_t) = *rcvr_ty {
+                        if let Ok(pick) = self.lookup_probe(
+                            span,
+                            item_name,
+                            new_rcvr_t,
+                            rcvr,
+                            crate::check::method::probe::ProbeScope::AllTraits,
+                        ) {
+                            debug!("try_alt_rcvr: pick candidate {:?}", pick);
+                            let did = Some(pick.item.container.id());
+                            // We don't want to suggest a container type when the missing
+                            // method is `.clone()` or `.deref()` otherwise we'd suggest
+                            // `Arc::new(foo).clone()`, which is far from what the user wants.
+                            let skip = [
+                                self.tcx.lang_items().clone_trait(),
+                                self.tcx.lang_items().deref_trait(),
+                                self.tcx.lang_items().deref_mut_trait(),
+                                self.tcx.lang_items().drop_trait(),
+                            ]
+                            .contains(&did);
+                            // Make sure the method is defined for the *actual* receiver: we don't
+                            // want to treat `Box<Self>` as a receiver if it only works because of
+                            // an autoderef to `&self`
+                            if pick.autoderefs == 0 && !skip {
+                                err.span_label(
+                                    pick.item.ident.span,
+                                    &format!("the method is available for `{}` here", new_rcvr_t),
+                                );
+                                err.multipart_suggestion(
+                                    "consider wrapping the receiver expression with the \
+                                        appropriate type",
+                                    vec![
+                                        (rcvr.span.shrink_to_lo(), format!("{}({}", pre, post)),
+                                        (rcvr.span.shrink_to_hi(), ")".to_string()),
+                                    ],
+                                    Applicability::MaybeIncorrect,
+                                );
+                                // We don't care about the other suggestions.
+                                alt_rcvr_sugg = true;
                             }
                         }
                     }

library/core/src/marker.rs

@@ -765,7 +765,7 @@ unsafe impl<T: ?Sized> Freeze for &mut T {}
 /// [`pin` module]: crate::pin
 #[stable(feature = "pin", since = "1.33.0")]
 #[rustc_on_unimplemented(
-    on(_Self = "std::future::Future", note = "consider using `Box::pin`",),
+    note = "consider using `Box::pin`",
     message = "`{Self}` cannot be unpinned"
 )]
 #[lang = "unpin"]

src/librustdoc/config.rs

@@ -378,6 +378,17 @@ impl Options {
             }
         }
 
+        // check for `--output-format=json`
+        if !matches!(matches.opt_str("output-format").as_deref(), None | Some("html"))
+            && !matches.opt_present("show-coverage")
+            && !nightly_options::is_unstable_enabled(matches)
+        {
+            rustc_session::early_error(
+                error_format,
+                "the -Z unstable-options flag must be passed to enable --output-format for documentation generation (see https://github.com/rust-lang/rust/issues/76578)",
+            );
+        }
+
         let to_check = matches.opt_strs("check-theme");
         if !to_check.is_empty() {
             let paths = theme::load_css_paths(static_files::themes::LIGHT.as_bytes());
@@ -574,13 +585,7 @@ impl Options {
         let output_format = match matches.opt_str("output-format") {
             Some(s) => match OutputFormat::try_from(s.as_str()) {
                 Ok(out_fmt) => {
-                    if out_fmt.is_json()
-                        && !(show_coverage || nightly_options::match_is_nightly_build(matches))
-                    {
-                        diag.struct_err("json output format isn't supported for doc generation")
-                            .emit();
-                        return Err(1);
-                    } else if !out_fmt.is_json() && show_coverage {
+                    if !out_fmt.is_json() && show_coverage {
                         diag.struct_err(
                             "html output format isn't supported for the --show-coverage option",
                         )
@@ -702,16 +707,10 @@ impl Options {
 
 /// Prints deprecation warnings for deprecated options
 fn check_deprecated_options(matches: &getopts::Matches, diag: &rustc_errors::Handler) {
-    let deprecated_flags = ["input-format", "output-format", "no-defaults", "passes"];
+    let deprecated_flags = ["input-format", "no-defaults", "passes"];
 
     for flag in deprecated_flags.iter() {
         if matches.opt_present(flag) {
-            if *flag == "output-format"
-                && (matches.opt_present("show-coverage")
-                    || nightly_options::match_is_nightly_build(matches))
-            {
-                continue;
-            }
             let mut err = diag.struct_warn(&format!("the `{}` flag is deprecated", flag));
             err.note(
                 "see issue #44136 <https://github.com/rust-lang/rust/issues/44136> \

src/test/run-make/unstable-flag-required/Makefile

@@ -0,0 +1,4 @@
+-include ../../run-make-fulldeps/tools.mk
+
+all:
+	$(RUSTDOC) --output-format=json x.html 2>&1 | diff - output-format-json.stderr

src/test/run-make/unstable-flag-required/README.md

@@ -0,0 +1,3 @@
+This is a collection of tests that verify `--unstable-options` is required.
+It should eventually be removed in favor of UI tests once compiletest stops
+passing --unstable-options by default (#82639).

src/test/run-make/unstable-flag-required/output-format-json.stderr

@@ -0,0 +1,2 @@
+error: the -Z unstable-options flag must be passed to enable --output-format for documentation generation (see https://github.com/rust-lang/rust/issues/76578)
+