From f7240e1c74fd19d09e183cedc7dd569c59a4bbd5 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Mon, 3 Sep 2018 22:24:11 +0200
Subject: Improve error display for codeblocks in rustdoc

---
 src/libsyntax/parse/lexer/mod.rs | 11 +++++++++++
 1 file changed, 11 insertions(+)

(limited to 'src/libsyntax')

diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index aa47d5bf669..7132dc342d2 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -238,6 +238,17 @@ impl<'a> StringReader<'a> {
         sr
     }
 
+    pub fn new_without_err(sess: &'a ParseSess,
+                           source_file: Lrc<syntax_pos::SourceFile>,
+                           override_span: Option<Span>) -> Result<Self, ()> {
+        let mut sr = StringReader::new_raw(sess, source_file, override_span);
+        if sr.advance_token().is_err() {
+            sr.emit_fatal_errors();
+            return Err(());
+        }
+        Ok(sr)
+    }
+
     pub fn retokenize(sess: &'a ParseSess, mut span: Span) -> Self {
         let begin = sess.source_map().lookup_byte_offset(span.lo());
         let end = sess.source_map().lookup_byte_offset(span.hi());
-- 
cgit 1.4.1-3-g733a5


From 322e46916e8251821543769ada7e38d6e4532da4 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Sat, 29 Sep 2018 18:34:49 +0200
Subject: Add a sentence before rustc errors

---
 src/librustdoc/html/highlight.rs          | 2 +-
 src/libsyntax/parse/lexer/mod.rs          | 4 +++-
 src/test/rustdoc-ui/invalid-syntax.stderr | 1 +
 3 files changed, 5 insertions(+), 2 deletions(-)

(limited to 'src/libsyntax')

diff --git a/src/librustdoc/html/highlight.rs b/src/librustdoc/html/highlight.rs
index a83f80dcc34..87b4527a2a7 100644
--- a/src/librustdoc/html/highlight.rs
+++ b/src/librustdoc/html/highlight.rs
@@ -44,7 +44,7 @@ pub fn render_with_highlighting(src: &str, class: Option<&str>,
     }
     write_header(class, &mut out).unwrap();
 
-    let lexer = match lexer::StringReader::new_without_err(&sess, fm, None) {
+    let lexer = match lexer::StringReader::new_without_err(&sess, fm, None, "Output from rustc:") {
         Ok(l) => l,
         Err(_) => {
             let first_line = src.lines().next().unwrap_or_else(|| "");
diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index 7132dc342d2..a814c88ee78 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -240,9 +240,11 @@ impl<'a> StringReader<'a> {
 
     pub fn new_without_err(sess: &'a ParseSess,
                            source_file: Lrc<syntax_pos::SourceFile>,
-                           override_span: Option<Span>) -> Result<Self, ()> {
+                           override_span: Option<Span>,
+                           prepend_error_text: &str) -> Result<Self, ()> {
         let mut sr = StringReader::new_raw(sess, source_file, override_span);
         if sr.advance_token().is_err() {
+            eprintln!("{}", prepend_error_text);
             sr.emit_fatal_errors();
             return Err(());
         }
diff --git a/src/test/rustdoc-ui/invalid-syntax.stderr b/src/test/rustdoc-ui/invalid-syntax.stderr
index 0661f0ab005..b5661332e8d 100644
--- a/src/test/rustdoc-ui/invalid-syntax.stderr
+++ b/src/test/rustdoc-ui/invalid-syntax.stderr
@@ -1,3 +1,4 @@
+Output from rustc:
 error: unknown start of token: /
  --> <stdin>:1:1
   |
-- 
cgit 1.4.1-3-g733a5