Return nil if no Language is found

lib/linguist/blob_helper.rb

@@ -256,7 +256,7 @@ module Linguist
           language
 
         # See if there is a Language for the extension
-        elsif language = Language.find_by_filename(pathname.to_s)
+        elsif language = pathname.language
           language
 
         # Try to detect Language from shebang line

lib/linguist/pathname.rb

@@ -52,25 +52,16 @@ module Linguist
     #   Pathname.new('file.rb').language
     #   # => Language['Ruby']
     #
-    # Returns a Langauge.
+    # Returns a Langauge or nil if none was found.
     def language
-      Language.find_by_filename(@path) || Language['Text']
+      @language ||= Language.find_by_filename(@path)
     end
 
-    # Internal: Has a language.
+    # Internal: Get the lexer of the path
-    #
-    # Will return false if language was guessed to be Text.
-    #
-    # Returns true or false.
-    def language?
-      Language.find_by_filename(@path) ? true : false
-    end
-
-    # Deprecated: Get the lexer of the path
     #
     # Returns a Lexer.
     def lexer
-      language.lexer
+      language ? language.lexer : Lexer['Text only']
     end
 
     # Public: Get the mime type

test/test_pathname.rb

@@ -24,7 +24,7 @@ class TestPathname < Test::Unit::TestCase
   end
 
   def test_language
-    assert_equal Language['Text'], Pathname.new(".rb").language
+    assert_nil Pathname.new(".rb").language
 
     assert_equal Language['Ruby'], Pathname.new("file.rb").language
     assert_equal Language['Ruby'], Pathname.new("./file.rb").language
@@ -37,7 +37,8 @@ class TestPathname < Test::Unit::TestCase
     assert_equal Language['Gentoo Ebuild'], Pathname.new("file.ebuild").language
     assert_equal Language['Python'], Pathname.new("itty.py").language
     assert_equal Language['Nu'], Pathname.new("itty.nu").language
-    assert_equal Language['Text'], Pathname.new("defun.kt").language
+
+    assert_nil Pathname.new("defun.kt").language
   end
 
   def test_lexer