Add `level` arg to `into_diagnostic`.

And make all hand-written `IntoDiagnostic` impls generic, by using
`DiagnosticBuilder::new(dcx, level, ...)` instead of e.g.
`dcx.struct_err(...)`.

This means the `create_*` functions are the source of the error level.
This change will let us remove `struct_diagnostic`.

Note: `#[rustc_lint_diagnostics]` is added to `DiagnosticBuilder::new`,
it's necessary to pass diagnostics tests now that it's used in
`into_diagnostic` functions.

1 files changed, 4 insertions, 7 deletions

diff --git a/compiler/rustc_symbol_mangling/src/errors.rs b/compiler/rustc_symbol_mangling/src/errors.rs
index ff253b6f467..06a2b3ca9c4 100644
--- a/compiler/rustc_symbol_mangling/src/errors.rs
+++ b/compiler/rustc_symbol_mangling/src/errors.rs
@@ -1,6 +1,6 @@
 //! Errors emitted by symbol_mangling.
 
-use rustc_errors::{ErrorGuaranteed, IntoDiagnostic};
+use rustc_errors::{DiagCtxt, DiagnosticBuilder, EmissionGuarantee, IntoDiagnostic, Level};
 use rustc_span::Span;
 use std::fmt;
 
@@ -13,15 +13,12 @@ pub struct TestOutput {
 // This diagnostic doesn't need translation because (a) it doesn't contain any
 // natural language, and (b) it's only used in tests. So we construct it
 // manually and avoid the fluent machinery.
-impl IntoDiagnostic<'_> for TestOutput {
-    fn into_diagnostic(
-        self,
-        dcx: &'_ rustc_errors::DiagCtxt,
-    ) -> rustc_errors::DiagnosticBuilder<'_, ErrorGuaranteed> {
+impl<G: EmissionGuarantee> IntoDiagnostic<'_, G> for TestOutput {
+    fn into_diagnostic(self, dcx: &'_ DiagCtxt, level: Level) -> DiagnosticBuilder<'_, G> {
         let TestOutput { span, kind, content } = self;
 
         #[allow(rustc::untranslatable_diagnostic)]
-        let mut diag = dcx.struct_err(format!("{kind}({content})"));
+        let mut diag = DiagnosticBuilder::new(dcx, level, format!("{kind}({content})"));
         diag.set_span(span);
         diag
     }