3 files changed, 9 insertions, 15 deletions

diff --git a/crates/ide/src/lib.rs b/crates/ide/src/lib.rs
index b24c664ba..99e45633e 100644
--- a/crates/ide/src/lib.rs
+++ b/crates/ide/src/lib.rs
@@ -244,6 +244,12 @@ impl Analysis {
         self.with_db(|db| db.parse(file_id).tree())
     }
 
+    /// Returns true if this file belongs to an immutable library.
+    pub fn is_library_file(&self, file_id: FileId) -> Cancelable<bool> {
+        use ide_db::base_db::SourceDatabaseExt;
+        self.with_db(|db| db.source_root(db.file_source_root(file_id)).is_library)
+    }
+
     /// Gets the file's `LineIndex`: data structure to convert between absolute
     /// offsets and line/column representation.
     pub fn file_line_index(&self, file_id: FileId) -> Cancelable<Arc<LineIndex>> {
diff --git a/crates/ide/src/syntax_highlighting/inject.rs b/crates/ide/src/syntax_highlighting/inject.rs
index 04fafd244..bc221d599 100644
--- a/crates/ide/src/syntax_highlighting/inject.rs
+++ b/crates/ide/src/syntax_highlighting/inject.rs
@@ -4,7 +4,7 @@ use std::mem;
 
 use either::Either;
 use hir::{InFile, Semantics};
-use ide_db::{call_info::ActiveParameter, SymbolKind};
+use ide_db::{call_info::ActiveParameter, helpers::rust_doc::is_rust_fence, SymbolKind};
 use syntax::{
     ast::{self, AstNode},
     AstToken, NodeOrToken, SyntaxNode, SyntaxToken, TextRange, TextSize,
@@ -78,17 +78,6 @@ pub(super) fn ra_fixture(
 }
 
 const RUSTDOC_FENCE: &'static str = "```";
-const RUSTDOC_FENCE_TOKENS: &[&'static str] = &[
-    "",
-    "rust",
-    "should_panic",
-    "ignore",
-    "no_run",
-    "compile_fail",
-    "edition2015",
-    "edition2018",
-    "edition2021",
-];
 
 /// Injection of syntax highlighting of doctests.
 pub(super) fn doc_comment(
@@ -174,8 +163,7 @@ pub(super) fn doc_comment(
                     is_codeblock = !is_codeblock;
                     // Check whether code is rust by inspecting fence guards
                     let guards = &line[idx + RUSTDOC_FENCE.len()..];
-                    let is_rust =
-                        guards.split(',').all(|sub| RUSTDOC_FENCE_TOKENS.contains(&sub.trim()));
+                    let is_rust = is_rust_fence(guards);
                     is_doctest = is_codeblock && is_rust;
                     continue;
                 }
diff --git a/crates/ide/src/syntax_highlighting/tests.rs b/crates/ide/src/syntax_highlighting/tests.rs
index 933cfa6f3..17cc6334b 100644
--- a/crates/ide/src/syntax_highlighting/tests.rs
+++ b/crates/ide/src/syntax_highlighting/tests.rs
@@ -307,7 +307,7 @@ fn benchmark_syntax_highlighting_parser() {
             .filter(|it| it.highlight.tag == HlTag::Symbol(SymbolKind::Function))
             .count()
     };
-    assert_eq!(hash, 1629);
+    assert_eq!(hash, 1632);
 }
 
 #[test]