1 files changed, 18 insertions, 8 deletions

diff --git a/crates/ra_ide/src/syntax_highlighting/injection.rs b/crates/ra_ide/src/syntax_highlighting/injection.rs
index 929a5cc5c..181c21256 100644
--- a/crates/ra_ide/src/syntax_highlighting/injection.rs
+++ b/crates/ra_ide/src/syntax_highlighting/injection.rs
@@ -7,7 +7,10 @@ use hir::Semantics;
 use ra_syntax::{ast, AstToken, SyntaxNode, SyntaxToken, TextRange, TextSize};
 use stdx::SepBy;
 
-use crate::{call_info::ActiveParameter, Analysis, HighlightTag, HighlightedRange, RootDatabase};
+use crate::{
+    call_info::ActiveParameter, Analysis, Highlight, HighlightModifier, HighlightTag,
+    HighlightedRange, RootDatabase,
+};
 
 use super::HighlightedRangeStack;
 
@@ -118,7 +121,7 @@ pub(super) fn extract_doc_comments(
                     range.start(),
                     range.start() + TextSize::try_from(pos).unwrap(),
                 ),
-                highlight: HighlightTag::Comment.into(),
+                highlight: HighlightTag::Comment | HighlightModifier::Documentation,
                 binding_hash: None,
             });
             line_start += range.len() - TextSize::try_from(pos).unwrap();
@@ -152,18 +155,24 @@ pub(super) fn highlight_doc_comment(
         let mut start_offset = None;
         let mut end_offset = None;
         for (line_start, orig_line_start) in range_mapping.range(..h.range.end()).rev() {
+            // It's possible for orig_line_start - line_start to be negative. Add h.range.start()
+            // here and remove it from the end range after the loop below so that the values are
+            // always non-negative.
+            let offset = h.range.start() + orig_line_start - line_start;
             if line_start <= &h.range.start() {
-                start_offset.get_or_insert(orig_line_start - line_start);
+                start_offset.get_or_insert(offset);
                 break;
             } else {
-                end_offset.get_or_insert(orig_line_start - line_start);
+                end_offset.get_or_insert(offset);
             }
         }
         if let Some(start_offset) = start_offset {
             h.range = TextRange::new(
-                h.range.start() + start_offset,
-                h.range.end() + end_offset.unwrap_or(start_offset),
+                start_offset,
+                h.range.end() + end_offset.unwrap_or(start_offset) - h.range.start(),
             );
+
+            h.highlight |= HighlightModifier::Injected;
             stack.add(h);
         }
     }
@@ -173,6 +182,7 @@ pub(super) fn highlight_doc_comment(
     for comment in new_comments {
         stack.add(comment);
     }
-    stack.pop_and_inject(false);
-    stack.pop_and_inject(true);
+    stack.pop_and_inject(None);
+    stack
+        .pop_and_inject(Some(Highlight::from(HighlightTag::Generic) | HighlightModifier::Injected));
 }