diff --git a/lib/linguist/vendor.yml b/lib/linguist/vendor.yml
index 0bf4bb6c..a1efbdfa 100644
--- a/lib/linguist/vendor.yml
+++ b/lib/linguist/vendor.yml
@@ -110,6 +110,9 @@
 # MathJax
 - (^|/)MathJax/
 
+# Codemirror
+- (^|/)[Cc]ode[Mm]irror/(lib|mode|theme|addon|keymap)
+
 # SyntaxHighlighter - http://alexgorbatchev.com/
 - (^|/)shBrush([^.]*)\.js$
 - (^|/)shCore\.js$
diff --git a/test/test_blob.rb b/test/test_blob.rb
index b0bdc368..8eec9c7a 100644
--- a/test/test_blob.rb
+++ b/test/test_blob.rb
@@ -297,6 +297,9 @@ class TestBlob < Test::Unit::TestCase
     assert blob("deps/http_parser/http_parser.c").vendored?
     assert blob("deps/v8/src/v8.h").vendored?
 
+    # Codemirror deps
+    assert blob("codemirror/mode/blah.js").vendored?
+
     # Debian packaging
     assert blob("debian/cron.d").vendored?