Rename DiagnosticBuilder as Diag.

Much better!

Note that this involves renaming (and updating the value of)
`DIAGNOSTIC_BUILDER` in clippy.

compiler/rustc_ast_lowering/src/errors.rs

@@ -1,5 +1,5 @@
 use rustc_errors::{
-    codes::*, AddToDiagnostic, DiagnosticArgFromDisplay, DiagnosticBuilder, EmissionGuarantee,
+    codes::*, AddToDiagnostic, Diag, DiagnosticArgFromDisplay, EmissionGuarantee,
     SubdiagnosticMessageOp,
 };
 use rustc_macros::{Diagnostic, Subdiagnostic};
@@ -44,7 +44,7 @@ pub struct InvalidAbiReason(pub &'static str);
 impl AddToDiagnostic for InvalidAbiReason {
     fn add_to_diagnostic_with<G: EmissionGuarantee, F: SubdiagnosticMessageOp<G>>(
         self,
-        diag: &mut DiagnosticBuilder<'_, G>,
+        diag: &mut Diag<'_, G>,
         _: F,
     ) {
         #[allow(rustc::untranslatable_diagnostic)]

compiler/rustc_ast_passes/src/errors.rs

@@ -2,8 +2,7 @@
 
 use rustc_ast::ParamKindOrd;
 use rustc_errors::{
-    codes::*, AddToDiagnostic, Applicability, DiagnosticBuilder, EmissionGuarantee,
-    SubdiagnosticMessageOp,
+    codes::*, AddToDiagnostic, Applicability, Diag, EmissionGuarantee, SubdiagnosticMessageOp,
 };
 use rustc_macros::{Diagnostic, Subdiagnostic};
 use rustc_span::{symbol::Ident, Span, Symbol};
@@ -377,7 +376,7 @@ pub struct EmptyLabelManySpans(pub Vec<Span>);
 impl AddToDiagnostic for EmptyLabelManySpans {
     fn add_to_diagnostic_with<G: EmissionGuarantee, F: SubdiagnosticMessageOp<G>>(
         self,
-        diag: &mut DiagnosticBuilder<'_, G>,
+        diag: &mut Diag<'_, G>,
         _: F,
     ) {
         diag.span_labels(self.0, "");
@@ -738,7 +737,7 @@ pub struct StableFeature {
 impl AddToDiagnostic for StableFeature {
     fn add_to_diagnostic_with<G: EmissionGuarantee, F: SubdiagnosticMessageOp<G>>(
         self,
-        diag: &mut DiagnosticBuilder<'_, G>,
+        diag: &mut Diag<'_, G>,
         _: F,
     ) {
         diag.arg("name", self.name);

compiler/rustc_attr/src/session_diagnostics.rs

@@ -2,7 +2,7 @@ use std::num::IntErrorKind;
 
 use rustc_ast as ast;
 use rustc_errors::{
-    codes::*, Applicability, DiagCtxt, DiagnosticBuilder, EmissionGuarantee, IntoDiagnostic, Level,
+    codes::*, Applicability, Diag, DiagCtxt, EmissionGuarantee, IntoDiagnostic, Level,
 };
 use rustc_macros::Diagnostic;
 use rustc_span::{Span, Symbol};
@@ -51,9 +51,9 @@ pub(crate) struct UnknownMetaItem<'a> {
 
 // Manual implementation to be able to format `expected` items correctly.
 impl<'a, G: EmissionGuarantee> IntoDiagnostic<'a, G> for UnknownMetaItem<'_> {
-    fn into_diagnostic(self, dcx: &'a DiagCtxt, level: Level) -> DiagnosticBuilder<'a, G> {
+    fn into_diagnostic(self, dcx: &'a DiagCtxt, level: Level) -> Diag<'a, G> {
         let expected = self.expected.iter().map(|name| format!("`{name}`")).collect::<Vec<_>>();
-        DiagnosticBuilder::new(dcx, level, fluent::attr_unknown_meta_item)
+        Diag::new(dcx, level, fluent::attr_unknown_meta_item)
             .with_span(self.span)
             .with_code(E0541)
             .with_arg("item", self.item)
@@ -198,8 +198,8 @@ pub(crate) struct UnsupportedLiteral {
 }
 
 impl<'a, G: EmissionGuarantee> IntoDiagnostic<'a, G> for UnsupportedLiteral {
-    fn into_diagnostic(self, dcx: &'a DiagCtxt, level: Level) -> DiagnosticBuilder<'a, G> {
-        let mut diag = DiagnosticBuilder::new(
+    fn into_diagnostic(self, dcx: &'a DiagCtxt, level: Level) -> Diag<'a, G> {
+        let mut diag = Diag::new(
             dcx,
             level,
             match self.reason {

compiler/rustc_borrowck/src/borrowck_errors.rs

@@ -1,7 +1,7 @@
 #![allow(rustc::diagnostic_outside_of_impl)]
 #![allow(rustc::untranslatable_diagnostic)]
 
-use rustc_errors::{codes::*, struct_span_code_err, DiagCtxt, DiagnosticBuilder};
+use rustc_errors::{codes::*, struct_span_code_err, Diag, DiagCtxt};
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::Span;
 
@@ -17,7 +17,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         place: &str,
         borrow_place: &str,
         value_place: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         self.dcx().create_err(crate::session_diagnostics::MoveBorrow {
             place,
             span,
@@ -33,7 +33,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         desc: &str,
         borrow_span: Span,
         borrow_desc: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -53,7 +53,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         old_loan_span: Span,
         old_opt_via: &str,
         old_load_end_span: Option<Span>,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         let via = |msg: &str| if msg.is_empty() { "".to_string() } else { format!(" (via {msg})") };
         let mut err = struct_span_code_err!(
             self.dcx(),
@@ -100,7 +100,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         desc: &str,
         old_loan_span: Span,
         old_load_end_span: Option<Span>,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         let mut err = struct_span_code_err!(
             self.dcx(),
             new_loan_span,
@@ -133,7 +133,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         noun_old: &str,
         old_opt_via: &str,
         previous_end_span: Option<Span>,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         let mut err = struct_span_code_err!(
             self.dcx(),
             new_loan_span,
@@ -165,7 +165,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         old_opt_via: &str,
         previous_end_span: Option<Span>,
         second_borrow_desc: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         let mut err = struct_span_code_err!(
             self.dcx(),
             new_loan_span,
@@ -197,7 +197,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         kind_old: &str,
         msg_old: &str,
         old_load_end_span: Option<Span>,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         let via = |msg: &str| if msg.is_empty() { "".to_string() } else { format!(" (via {msg})") };
         let mut err = struct_span_code_err!(
             self.dcx(),
@@ -238,7 +238,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         span: Span,
         borrow_span: Span,
         desc: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -255,20 +255,20 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         span: Span,
         desc: &str,
         is_arg: bool,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         let msg = if is_arg { "to immutable argument" } else { "twice to immutable variable" };
         struct_span_code_err!(self.dcx(), span, E0384, "cannot assign {} {}", msg, desc)
     }
 
-    pub(crate) fn cannot_assign(&self, span: Span, desc: &str) -> DiagnosticBuilder<'tcx> {
+    pub(crate) fn cannot_assign(&self, span: Span, desc: &str) -> Diag<'tcx> {
         struct_span_code_err!(self.dcx(), span, E0594, "cannot assign to {}", desc)
     }
 
     pub(crate) fn cannot_move_out_of(
         &self,
         move_from_span: Span,
         move_from_desc: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             move_from_span,
@@ -286,7 +286,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         move_from_span: Span,
         ty: Ty<'_>,
         is_index: Option<bool>,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         let type_name = match (&ty.kind(), is_index) {
             (&ty::Array(_, _), Some(true)) | (&ty::Array(_, _), None) => "array",
             (&ty::Slice(_), _) => "slice",
@@ -307,7 +307,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         &self,
         move_from_span: Span,
         container_ty: Ty<'_>,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             move_from_span,
@@ -324,7 +324,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         verb: &str,
         optional_adverb_for_moved: &str,
         moved_path: Option<String>,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         let moved_path = moved_path.map(|mp| format!(": `{mp}`")).unwrap_or_default();
 
         struct_span_code_err!(
@@ -343,7 +343,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         span: Span,
         path: &str,
         reason: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -361,7 +361,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         immutable_place: &str,
         immutable_section: &str,
         action: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             mutate_span,
@@ -379,7 +379,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         &self,
         span: Span,
         yield_span: Span,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         let coroutine_kind = self.body.coroutine.as_ref().unwrap().coroutine_kind;
         struct_span_code_err!(
             self.dcx(),
@@ -390,10 +390,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         .with_span_label(yield_span, "possible yield occurs here")
     }
 
-    pub(crate) fn cannot_borrow_across_destructor(
-        &self,
-        borrow_span: Span,
-    ) -> DiagnosticBuilder<'tcx> {
+    pub(crate) fn cannot_borrow_across_destructor(&self, borrow_span: Span) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             borrow_span,
@@ -402,11 +399,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         )
     }
 
-    pub(crate) fn path_does_not_live_long_enough(
-        &self,
-        span: Span,
-        path: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    pub(crate) fn path_does_not_live_long_enough(&self, span: Span, path: &str) -> Diag<'tcx> {
         struct_span_code_err!(self.dcx(), span, E0597, "{} does not live long enough", path,)
     }
 
@@ -416,7 +409,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         return_kind: &str,
         reference_desc: &str,
         path_desc: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -439,7 +432,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         borrowed_path: &str,
         capture_span: Span,
         scope: &str,
-    ) -> DiagnosticBuilder<'tcx> {
+    ) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             closure_span,
@@ -451,10 +444,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         .with_span_label(closure_span, format!("may outlive borrowed value {borrowed_path}"))
     }
 
-    pub(crate) fn thread_local_value_does_not_live_long_enough(
-        &self,
-        span: Span,
-    ) -> DiagnosticBuilder<'tcx> {
+    pub(crate) fn thread_local_value_does_not_live_long_enough(&self, span: Span) -> Diag<'tcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -463,10 +453,7 @@ impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
         )
     }
 
-    pub(crate) fn temporary_value_borrowed_for_too_long(
-        &self,
-        span: Span,
-    ) -> DiagnosticBuilder<'tcx> {
+    pub(crate) fn temporary_value_borrowed_for_too_long(&self, span: Span) -> Diag<'tcx> {
         struct_span_code_err!(self.dcx(), span, E0716, "temporary value dropped while borrowed",)
     }
 }
@@ -475,7 +462,7 @@ pub(crate) fn borrowed_data_escapes_closure<'tcx>(
     tcx: TyCtxt<'tcx>,
     escape_span: Span,
     escapes_from: &str,
-) -> DiagnosticBuilder<'tcx> {
+) -> Diag<'tcx> {
     struct_span_code_err!(
         tcx.dcx(),
         escape_span,