Lint elided lifetimes in path during lifetime resolution.

2 files changed, 16 insertions, 23 deletions

diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
index 2b3a538772e..a561475c76a 100644
--- a/compiler/rustc_ast_lowering/src/lib.rs
+++ b/compiler/rustc_ast_lowering/src/lib.rs
@@ -1928,6 +1928,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 let param_name = match lt.name {
                     hir::LifetimeName::Param(param_name) => param_name,
                     hir::LifetimeName::Implicit
+                    | hir::LifetimeName::ImplicitMissing
                     | hir::LifetimeName::Underscore
                     | hir::LifetimeName::Static => hir::ParamName::Plain(lt.name.ident()),
                     hir::LifetimeName::ImplicitObjectLifetimeDefault => {
@@ -2322,11 +2323,12 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         &'s mut self,
         span: Span,
         count: usize,
+        param_mode: ParamMode,
     ) -> impl Iterator<Item = hir::Lifetime> + Captures<'a> + Captures<'s> + Captures<'hir> {
-        (0..count).map(move |_| self.elided_path_lifetime(span))
+        (0..count).map(move |_| self.elided_path_lifetime(span, param_mode))
     }
 
-    fn elided_path_lifetime(&mut self, span: Span) -> hir::Lifetime {
+    fn elided_path_lifetime(&mut self, span: Span, param_mode: ParamMode) -> hir::Lifetime {
         match self.anonymous_lifetime_mode {
             AnonymousLifetimeMode::CreateParameter => {
                 // We should have emitted E0726 when processing this path above
@@ -2342,7 +2344,12 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             // lifetime. Instead, we simply create an implicit lifetime, which will be checked
             // later, at which point a suitable error will be emitted.
             AnonymousLifetimeMode::PassThrough | AnonymousLifetimeMode::ReportError => {
-                self.new_implicit_lifetime(span)
+                if param_mode == ParamMode::Explicit {
+                    let id = self.resolver.next_node_id();
+                    self.new_named_lifetime(id, span, hir::LifetimeName::ImplicitMissing)
+                } else {
+                    self.new_implicit_lifetime(span)
+                }
             }
         }
     }
@@ -2536,7 +2543,9 @@ fn lifetimes_from_impl_trait_bounds(
 
         fn visit_lifetime(&mut self, lifetime: &'v hir::Lifetime) {
             let name = match lifetime.name {
-                hir::LifetimeName::Implicit | hir::LifetimeName::Underscore => {
+                hir::LifetimeName::Implicit
+                | hir::LifetimeName::ImplicitMissing
+                | hir::LifetimeName::Underscore => {
                     if self.collect_elided_lifetimes {
                         // Use `'_` for both implicit and underscore lifetimes in
                         // `type Foo<'_> = impl SomeTrait<'_>;`.
diff --git a/compiler/rustc_ast_lowering/src/path.rs b/compiler/rustc_ast_lowering/src/path.rs
index 929f427484d..ab87867bb03 100644
--- a/compiler/rustc_ast_lowering/src/path.rs
+++ b/compiler/rustc_ast_lowering/src/path.rs
@@ -7,8 +7,6 @@ use rustc_hir as hir;
 use rustc_hir::def::{DefKind, PartialRes, Res};
 use rustc_hir::def_id::DefId;
 use rustc_hir::GenericArg;
-use rustc_session::lint::builtin::ELIDED_LIFETIMES_IN_PATHS;
-use rustc_session::lint::BuiltinLintDiagnostics;
 use rustc_span::symbol::Ident;
 use rustc_span::{BytePos, Span, DUMMY_SP};
 
@@ -275,7 +273,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             // See rustc_resolve::late::lifetimes::LifetimeContext::add_missing_lifetime_specifiers_label
             let elided_lifetime_span = if generic_args.span.is_empty() {
                 // If there are no brackets, use the identifier span.
-                segment.ident.span
+                path_span
             } else if generic_args.is_empty() {
                 // If there are brackets, but not generic arguments, then use the opening bracket
                 generic_args.span.with_hi(generic_args.span.lo() + BytePos(1))
@@ -284,7 +282,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 generic_args.span.with_lo(generic_args.span.lo() + BytePos(1)).shrink_to_lo()
             };
             generic_args.args = self
-                .elided_path_lifetimes(elided_lifetime_span, expected_lifetimes)
+                .elided_path_lifetimes(elided_lifetime_span, expected_lifetimes, param_mode)
                 .map(GenericArg::Lifetime)
                 .chain(generic_args.args.into_iter())
                 .collect();
@@ -329,21 +327,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                         err.note("assuming a `'static` lifetime...");
                         err.emit();
                     }
-                    AnonymousLifetimeMode::PassThrough | AnonymousLifetimeMode::ReportError => {
-                        self.resolver.lint_buffer().buffer_lint_with_diagnostic(
-                            ELIDED_LIFETIMES_IN_PATHS,
-                            CRATE_NODE_ID,
-                            path_span,
-                            "hidden lifetime parameters in types are deprecated",
-                            BuiltinLintDiagnostics::ElidedLifetimesInPaths(
-                                expected_lifetimes,
-                                path_span,
-                                incl_angl_brckt,
-                                insertion_sp,
-                                suggestion,
-                            ),
-                        );
-                    }
+                    AnonymousLifetimeMode::PassThrough | AnonymousLifetimeMode::ReportError => {}
                 }
             }
         }