Rollup merge of #66068 - euclio:null-emitter, r=estebank

use silent emitter for rustdoc highlighting pass

Partially addresses #63284.

1 files changed, 7 insertions, 1 deletions

diff --git a/src/libsyntax/sess.rs b/src/libsyntax/sess.rs
index 323fe01f067..30f8c56a056 100644
--- a/src/libsyntax/sess.rs
+++ b/src/libsyntax/sess.rs
@@ -6,7 +6,7 @@ use crate::early_buffered_lints::{BufferedEarlyLint, BufferedEarlyLintId};
 use crate::source_map::{SourceMap, FilePathMapping};
 use crate::feature_gate::UnstableFeatures;
 
-use errors::{Applicability, Handler, ColorConfig, DiagnosticBuilder};
+use errors::{Applicability, emitter::SilentEmitter, Handler, ColorConfig, DiagnosticBuilder};
 use rustc_data_structures::fx::{FxHashSet, FxHashMap};
 use rustc_data_structures::sync::{Lrc, Lock, Once};
 use syntax_pos::{Symbol, Span, MultiSpan};
@@ -107,6 +107,12 @@ impl ParseSess {
         }
     }
 
+    pub fn with_silent_emitter() -> Self {
+        let cm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
+        let handler = Handler::with_emitter(false, None, Box::new(SilentEmitter));
+        ParseSess::with_span_handler(handler, cm)
+    }
+
     #[inline]
     pub fn source_map(&self) -> &SourceMap {
         &self.source_map