diff --git a/test/fixtures/defun.kt b/test/fixtures/defu.nkt
similarity index 100%
rename from test/fixtures/defun.kt
rename to test/fixtures/defu.nkt
diff --git a/test/test_blob.rb b/test/test_blob.rb
index 2457ca66..a1a3fe41 100644
--- a/test/test_blob.rb
+++ b/test/test_blob.rb
@@ -262,7 +262,7 @@ class TestBlob < Test::Unit::TestCase
   def test_indexable
     assert blob("file.txt").indexable?
     assert blob("foo.rb").indexable?
-    assert !blob("defun.kt").indexable?
+    assert !blob("defu.nkt").indexable?
     assert !blob("dump.sql").indexable?
     assert !blob("github.po").indexable?
     assert !blob("linguist.gem").indexable?
@@ -423,6 +423,9 @@ class TestBlob < Test::Unit::TestCase
 
     # Tea
     assert_equal Language['Tea'], blob("foo.tea").language
+
+    # Kotlin
+    assert_equal Language['Kotlin'], blob("Foo.kt").language
   end
 
   def test_lexer
diff --git a/test/test_language.rb b/test/test_language.rb
index e1876898..b636776a 100644
--- a/test/test_language.rb
+++ b/test/test_language.rb
@@ -251,7 +251,7 @@ class TestLanguage < Test::Unit::TestCase
     assert_equal Language['PHP'], Language.find_by_extension('php5')
     assert_equal Language['PowerShell'], Language.find_by_extension('psm1')
     assert_equal Language['PowerShell'], Language.find_by_extension('ps1')
-    assert_nil Language.find_by_extension('.kt')
+    assert_nil Language.find_by_extension('.nkt')
   end
 
   def test_find_all_by_extension
@@ -270,7 +270,7 @@ class TestLanguage < Test::Unit::TestCase
     assert_equal Language['Ruby'], Language.find_by_filename('Rakefile')
     assert_nil Language.find_by_filename('rb')
     assert_nil Language.find_by_filename('.rb')
-    assert_nil Language.find_by_filename('.kt')
+    assert_nil Language.find_by_filename('.nkt')
   end
 
   def test_find
diff --git a/test/test_pathname.rb b/test/test_pathname.rb
index 714657ee..2d7f8427 100644
--- a/test/test_pathname.rb
+++ b/test/test_pathname.rb
@@ -41,7 +41,7 @@ class TestPathname < Test::Unit::TestCase
     assert_equal Language['Python'], Pathname.new("itty.py").language
     assert_equal Language['Nu'], Pathname.new("itty.nu").language
 
-    assert_nil Pathname.new("defun.kt").language
+    assert_nil Pathname.new("defu.nkt").language
   end
 
   def test_lexer
@@ -50,13 +50,13 @@ class TestPathname < Test::Unit::TestCase
     assert_equal Lexer['Bash'],      Pathname.new("file.ebuild").lexer
     assert_equal Lexer['Python'],    Pathname.new("itty.py").lexer
     assert_equal Lexer['Scheme'],    Pathname.new("itty.nu").lexer
-    assert_equal Lexer['Text only'], Pathname.new("defun.kt").lexer
+    assert_equal Lexer['Text only'], Pathname.new("defu.nkt").lexer
   end
 
   def test_mime_type
     assert_equal 'application/x-ruby', Pathname.new("file.rb").mime_type
     assert_equal 'application/javascript', Pathname.new("file.js").mime_type
     assert_equal 'application/x-python', Pathname.new("itty.py").mime_type
-    assert_equal 'text/plain', Pathname.new("defun.kt").mime_type
+    assert_equal 'text/plain', Pathname.new("defu.nkt").mime_type
   end
 end