Merge from rustc

3 files changed, 15 insertions, 7 deletions

diff --git a/compiler/rustc_parse/messages.ftl b/compiler/rustc_parse/messages.ftl
index 2c4bc7bb568..05b6c406206 100644
--- a/compiler/rustc_parse/messages.ftl
+++ b/compiler/rustc_parse/messages.ftl
@@ -509,7 +509,7 @@ parse_maybe_fn_typo_with_impl = you might have meant to write `impl` instead of
 
 parse_maybe_recover_from_bad_qpath_stage_2 =
     missing angle brackets in associated item path
-    .suggestion = try: `{$ty}`
+    .suggestion = types that don't start with an identifier need to be surrounded with angle brackets in qualified paths
 
 parse_maybe_recover_from_bad_type_plus =
     expected a path on the left-hand side of `+`, not `{$ty}`
diff --git a/compiler/rustc_parse/src/errors.rs b/compiler/rustc_parse/src/errors.rs
index 5d3ec683552..7c75e440aaa 100644
--- a/compiler/rustc_parse/src/errors.rs
+++ b/compiler/rustc_parse/src/errors.rs
@@ -59,9 +59,18 @@ pub(crate) enum BadTypePlusSub {
 #[diag(parse_maybe_recover_from_bad_qpath_stage_2)]
 pub(crate) struct BadQPathStage2 {
     #[primary_span]
-    #[suggestion(code = "", applicability = "maybe-incorrect")]
     pub span: Span,
-    pub ty: String,
+    #[subdiagnostic]
+    pub wrap: WrapType,
+}
+
+#[derive(Subdiagnostic)]
+#[multipart_suggestion(parse_suggestion, applicability = "machine-applicable")]
+pub(crate) struct WrapType {
+    #[suggestion_part(code = "<")]
+    pub lo: Span,
+    #[suggestion_part(code = ">")]
+    pub hi: Span,
 }
 
 #[derive(Diagnostic)]
diff --git a/compiler/rustc_parse/src/parser/diagnostics.rs b/compiler/rustc_parse/src/parser/diagnostics.rs
index 6c8ef34063f..06b1b1523ed 100644
--- a/compiler/rustc_parse/src/parser/diagnostics.rs
+++ b/compiler/rustc_parse/src/parser/diagnostics.rs
@@ -16,7 +16,7 @@ use crate::errors::{
     StructLiteralBodyWithoutPath, StructLiteralBodyWithoutPathSugg, StructLiteralNeedingParens,
     StructLiteralNeedingParensSugg, SuggAddMissingLetStmt, SuggEscapeIdentifier, SuggRemoveComma,
     TernaryOperator, UnexpectedConstInGenericParam, UnexpectedConstParamDeclaration,
-    UnexpectedConstParamDeclarationSugg, UnmatchedAngleBrackets, UseEqInstead,
+    UnexpectedConstParamDeclarationSugg, UnmatchedAngleBrackets, UseEqInstead, WrapType,
 };
 
 use crate::fluent_generated as fluent;
@@ -1589,10 +1589,9 @@ impl<'a> Parser<'a> {
         self.parse_path_segments(&mut path.segments, T::PATH_STYLE, None)?;
         path.span = ty_span.to(self.prev_token.span);
 
-        let ty_str = self.span_to_snippet(ty_span).unwrap_or_else(|_| pprust::ty_to_string(&ty));
         self.sess.emit_err(BadQPathStage2 {
-            span: path.span,
-            ty: format!("<{}>::{}", ty_str, pprust::path_to_string(&path)),
+            span: ty_span,
+            wrap: WrapType { lo: ty_span.shrink_to_lo(), hi: ty_span.shrink_to_hi() },
         });
 
         let path_span = ty_span.shrink_to_hi(); // Use an empty path since `position == 0`.