Remove SubDiagnostic::render_span.

It's only ever set to `None`.

Author: nnethercote

compiler/rustc_errors/src/diagnostic.rs

@@ -163,7 +163,6 @@ pub struct SubDiagnostic {
     pub level: Level,
     pub messages: Vec<(DiagnosticMessage, Style)>,
     pub span: MultiSpan,
-    pub render_span: Option<MultiSpan>,
 }
 
 #[derive(Debug, PartialEq, Eq)]
@@ -960,7 +959,6 @@ impl Diagnostic {
                 Style::NoStyle,
             )],
             span,
-            render_span: None,
         };
         self.children.push(sub);
     }
@@ -977,7 +975,7 @@ impl Diagnostic {
             .into_iter()
             .map(|m| (self.subdiagnostic_message_to_diagnostic_message(m.0), m.1))
             .collect();
-        let sub = SubDiagnostic { level, messages, span, render_span: None };
+        let sub = SubDiagnostic { level, messages, span };
         self.children.push(sub);
     }
 

compiler/rustc_errors/src/emitter.rs

@@ -352,7 +352,6 @@ pub trait Emitter: Translate {
                     level: Level::Note,
                     messages: vec![(DiagnosticMessage::from(msg), Style::NoStyle)],
                     span: MultiSpan::new(),
-                    render_span: None,
                 });
             }
         }
@@ -2118,7 +2117,7 @@ impl EmitterWriter {
                 }
                 if !self.short_message {
                     for child in children {
-                        let span = child.render_span.as_ref().unwrap_or(&child.span);
+                        let span = &child.span;
                         if let Err(err) = self.emit_messages_default_inner(
                             span,
                             &child.messages,

compiler/rustc_errors/src/json.rs

@@ -424,11 +424,7 @@ impl Diagnostic {
             message: translated_message.to_string(),
             code: None,
             level: diag.level.to_str(),
-            spans: diag
-                .render_span
-                .as_ref()
-                .map(|sp| DiagnosticSpan::from_multispan(sp, args, je))
-                .unwrap_or_else(|| DiagnosticSpan::from_multispan(&diag.span, args, je)),
+            spans: DiagnosticSpan::from_multispan(&diag.span, args, je),
             children: vec![],
             rendered: None,
         }