From 5ecc4421d7df3dce927d698024a43e0fc1450af0 Mon Sep 17 00:00:00 2001
From: Joshua Peek <josh@joshpeek.com>
Date: Tue, 5 Jul 2011 09:34:33 -0500
Subject: [PATCH] Basic Matlab detection

Fixes #15
---
 lib/linguist/blob_helper.rb | 34 ++++++++++++++++++++++++++++++++++
 test/test_blob.rb           |  6 ++++++
 2 files changed, 40 insertions(+)

diff --git a/lib/linguist/blob_helper.rb b/lib/linguist/blob_helper.rb
index 538fe5c6..f18a9204 100644
--- a/lib/linguist/blob_helper.rb
+++ b/lib/linguist/blob_helper.rb
@@ -278,6 +278,9 @@ module Linguist
       # If its a header file (.h) try to guess the language
       header_language ||
 
+        # If it's a .m file, try to guess the language
+        m_language ||
+
         # If it's a .r file, try to guess the language
         r_language ||
 
@@ -310,6 +313,37 @@ module Linguist
       end
     end
 
+    # Internal: Guess language of .m files.
+    #
+    # Objective-C heuristics:
+    # * Keywords
+    #
+    # Matlab heuristics:
+    # * Leading function keyword
+    # * "%" comments
+    #
+    # Returns a Language.
+    def m_language
+      return unless extname == '.m'
+
+      # Objective-C keywords
+      if lines.grep(/^#import|@(interface|implementation|property|synthesize|end)/).any?
+        Language['Objective-C']
+
+      # File function
+      elsif lines.first.to_s =~ /^function /
+        Language['Matlab']
+
+      # Matlab comment
+      elsif lines.grep(/^%/).any?
+        Language['Matlab']
+
+      # Fallback to Objective-C, don't want any Matlab false positives
+      else
+        Language['Objective-C']
+      end
+    end
+
     # Internal: Guess language of .r files.
     #
     # Returns a Language.
diff --git a/test/test_blob.rb b/test/test_blob.rb
index 0a89031e..ff045d9c 100644
--- a/test/test_blob.rb
+++ b/test/test_blob.rb
@@ -234,6 +234,12 @@ class TestBlob < Test::Unit::TestCase
     assert_equal Language['R'],           blob("hello-r.R").language
     assert_equal Language['Rebol'],       blob("hello-rebol.r").language
 
+    # .m disambiguation
+    assert_equal Language['Objective-C'], blob("Foo.m").language
+    assert_equal Language['Objective-C'], blob("hello.m").language
+    assert_equal Language['Matlab'], blob("matlab_function.m").language
+    # assert_equal Language['Matlab'], blob("matlab_script.m").language
+
     # ML
     assert_equal Language['OCaml'],       blob("Foo.ml").language
     assert_equal Language['Standard ML'], blob("Foo.sig").language