Auto merge of #97284 - b-naber:constraint-dyn-impl-suggestion, r=estebank

Add suggestion for relaxing static lifetime bounds on dyn trait impls in NLL

This PR introduces suggestions for relaxing static lifetime bounds on impls of dyn trait items for NLL similar to what is already available in lexical region diagnostics.

Fixes #95701

r? `@estebank`

Author: bors

compiler/rustc_borrowck/src/constraints/mod.rs

@@ -95,7 +95,7 @@ pub struct OutlivesConstraint<'tcx> {
     pub span: Span,
 
     /// What caused this constraint?
-    pub category: ConstraintCategory,
+    pub category: ConstraintCategory<'tcx>,
 
     /// Variance diagnostic information
     pub variance_info: VarianceDiagInfo<'tcx>,

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -788,7 +788,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         err: &mut Diagnostic,
         location: Location,
         issued_borrow: &BorrowData<'tcx>,
-        explanation: BorrowExplanation,
+        explanation: BorrowExplanation<'tcx>,
     ) {
         let used_in_call = matches!(
             explanation,
@@ -1088,7 +1088,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 BorrowExplanation::MustBeValidFor {
                     category:
                         category @ (ConstraintCategory::Return(_)
-                        | ConstraintCategory::CallArgument
+                        | ConstraintCategory::CallArgument(_)
                         | ConstraintCategory::OpaqueType),
                     from_closure: false,
                     ref region_name,
@@ -1147,7 +1147,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         borrow: &BorrowData<'tcx>,
         drop_span: Span,
         borrow_spans: UseSpans<'tcx>,
-        explanation: BorrowExplanation,
+        explanation: BorrowExplanation<'tcx>,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
         debug!(
             "report_local_value_does_not_live_long_enough(\
@@ -1352,7 +1352,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         drop_span: Span,
         borrow_spans: UseSpans<'tcx>,
         proper_span: Span,
-        explanation: BorrowExplanation,
+        explanation: BorrowExplanation<'tcx>,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
         debug!(
             "report_temporary_value_does_not_live_long_enough(\
@@ -1410,7 +1410,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         borrow: &BorrowData<'tcx>,
         borrow_span: Span,
         return_span: Span,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         opt_place_desc: Option<&String>,
     ) -> Option<DiagnosticBuilder<'cx, ErrorGuaranteed>> {
         let return_kind = match category {
@@ -1508,7 +1508,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         use_span: UseSpans<'tcx>,
         var_span: Span,
         fr_name: &RegionName,
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         constraint_span: Span,
         captured_var: &str,
     ) -> DiagnosticBuilder<'cx, ErrorGuaranteed> {
@@ -1559,7 +1559,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 let msg = format!("{} is returned here", kind);
                 err.span_note(constraint_span, &msg);
             }
-            ConstraintCategory::CallArgument => {
+            ConstraintCategory::CallArgument(_) => {
                 fr_name.highlight_region_name(&mut err);
                 if matches!(use_span.generator_kind(), Some(GeneratorKind::Async(_))) {
                     err.note(

compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs

@@ -24,7 +24,7 @@ use crate::{
 use super::{find_use, RegionName, UseSpans};
 
 #[derive(Debug)]
-pub(crate) enum BorrowExplanation {
+pub(crate) enum BorrowExplanation<'tcx> {
     UsedLater(LaterUseKind, Span, Option<Span>),
     UsedLaterInLoop(LaterUseKind, Span, Option<Span>),
     UsedLaterWhenDropped {
@@ -33,7 +33,7 @@ pub(crate) enum BorrowExplanation {
         should_note_order: bool,
     },
     MustBeValidFor {
-        category: ConstraintCategory,
+        category: ConstraintCategory<'tcx>,
         from_closure: bool,
         span: Span,
         region_name: RegionName,
@@ -51,11 +51,11 @@ pub(crate) enum LaterUseKind {
     Other,
 }
 
-impl BorrowExplanation {
+impl<'tcx> BorrowExplanation<'tcx> {
     pub(crate) fn is_explained(&self) -> bool {
         !matches!(self, BorrowExplanation::Unexplained)
     }
-    pub(crate) fn add_explanation_to_diagnostic<'tcx>(
+    pub(crate) fn add_explanation_to_diagnostic(
         &self,
         tcx: TyCtxt<'tcx>,
         body: &Body<'tcx>,
@@ -276,7 +276,7 @@ impl BorrowExplanation {
     pub(crate) fn add_lifetime_bound_suggestion_to_diagnostic(
         &self,
         err: &mut Diagnostic,
-        category: &ConstraintCategory,
+        category: &ConstraintCategory<'tcx>,
         span: Span,
         region_name: &RegionName,
     ) {
@@ -305,7 +305,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         &self,
         borrow_region: RegionVid,
         outlived_region: RegionVid,
-    ) -> (ConstraintCategory, bool, Span, Option<RegionName>) {
+    ) -> (ConstraintCategory<'tcx>, bool, Span, Option<RegionName>) {
         let BlameConstraint { category, from_closure, cause, variance_info: _ } =
             self.regioncx.best_blame_constraint(
                 &self.body,
@@ -337,7 +337,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         location: Location,
         borrow: &BorrowData<'tcx>,
         kind_place: Option<(WriteKind, Place<'tcx>)>,
-    ) -> BorrowExplanation {
+    ) -> BorrowExplanation<'tcx> {
         debug!(
             "explain_why_borrow_contains_point(location={:?}, borrow={:?}, kind_place={:?})",
             location, borrow, kind_place

compiler/rustc_borrowck/src/diagnostics/outlives_suggestion.rs

@@ -161,7 +161,7 @@ impl OutlivesSuggestionBuilder {
     pub(crate) fn intermediate_suggestion(
         &mut self,
         mbcx: &MirBorrowckCtxt<'_, '_>,
-        errci: &ErrorConstraintInfo,
+        errci: &ErrorConstraintInfo<'_>,
         diag: &mut Diagnostic,
     ) {
         // Emit an intermediate note.