Prefer `DiagnosticBuilder` over `Diagnostic` in diagnostic modifiers.

There are lots of functions that modify a diagnostic. This can be via a
`&mut Diagnostic` or a `&mut DiagnosticBuilder`, because the latter type
wraps the former and impls `DerefMut`.

This commit converts all the `&mut Diagnostic` occurrences to `&mut
DiagnosticBuilder`. This is a step towards greatly simplifying
`Diagnostic`. Some of the relevant function are made generic, because
they deal with both errors and warnings. No function bodies are changed,
because all the modifier methods are available on both `Diagnostic` and
`DiagnosticBuilder`.

1 files changed, 3 insertions, 3 deletions

diff --git a/compiler/rustc_parse/src/lexer/diagnostics.rs b/compiler/rustc_parse/src/lexer/diagnostics.rs
index b1bd4ac75e5..52a029b20f6 100644
--- a/compiler/rustc_parse/src/lexer/diagnostics.rs
+++ b/compiler/rustc_parse/src/lexer/diagnostics.rs
@@ -1,6 +1,6 @@
 use super::UnmatchedDelim;
 use rustc_ast::token::Delimiter;
-use rustc_errors::Diagnostic;
+use rustc_errors::DiagnosticBuilder;
 use rustc_span::source_map::SourceMap;
 use rustc_span::Span;
 
@@ -31,7 +31,7 @@ pub fn same_indentation_level(sm: &SourceMap, open_sp: Span, close_sp: Span) ->
 // When we get a `)` or `]` for `{`, we should emit help message here
 // it's more friendly compared to report `unmatched error` in later phase
 pub fn report_missing_open_delim(
-    err: &mut Diagnostic,
+    err: &mut DiagnosticBuilder<'_>,
     unmatched_delims: &[UnmatchedDelim],
 ) -> bool {
     let mut reported_missing_open = false;
@@ -55,7 +55,7 @@ pub fn report_missing_open_delim(
 }
 
 pub fn report_suspicious_mismatch_block(
-    err: &mut Diagnostic,
+    err: &mut DiagnosticBuilder<'_>,
     diag_info: &TokenTreeDiagInfo,
     sm: &SourceMap,
     delim: Delimiter,