Ensure that git 1.7.5 or newer is installed

Fixes #2651

CHANGELOG.md

@@ -49,6 +49,10 @@ To install or update CocoaPods see this [guide](http://docs.cocoapods.org/guides
   [Kyle Fuller](https://github.com/kylef)
   [#2083](https://github.com/CocoaPods/CocoaPods/issues/2083)
 
+* Ensure that git 1.7.5 or newer is installed when running pod.  
+  [Kyle Fuller](https://github.com/kylef)
+  [#2651](https://github.com/CocoaPods/CocoaPods/issues/2651)
+
 
 ## 0.34.2
 

lib/cocoapods/command.rb

@@ -42,6 +42,8 @@ module Pod
 
     def self.run(argv)
       help! 'You cannot run CocoaPods as root.' if Process.uid == 0
+      verify_git_version!
+
       super(argv)
       UI.print_warnings
     end
@@ -111,5 +113,18 @@ module Pod
         raise Informative, "No `Podfile.lock' found in the project directory, run `pod install'."
       end
     end
+
+    def self.verify_git_version!
+      begin
+        git_version = `git version`.strip
+      rescue Errno::ENOENT
+        help! 'CocoaPods requires you to have `git` installed.'
+      end
+
+      git_version = Version.new(git_version.split[2])
+      if git_version < Pod::Version.new('1.7.5')
+        help! 'CocoaPods requires git version 1.7.5 or newer. Please update git.'
+      end
+    end
   end
 end

spec/functional/command_spec.rb

@@ -17,5 +17,15 @@ module Pod
       Process.stubs(:uid).returns(0)
       lambda { Pod::Command.run(['--version']) }.should.raise CLAide::Help
     end
+
+    it "doesn't let you run without git installed" do
+      Pod::Command.expects(:`).with('git version').raises(Errno::ENOENT)
+      lambda { Pod::Command.run(['--version']) }.should.raise CLAide::Help
+    end
+
+    it "doesn't let you run with git version < 1.7.5" do
+      Pod::Command.expects(:`).with('git version').returns('git version 1.7.4.1 (Apple Git-50)')
+      lambda { Pod::Command.run(['--version']) }.should.raise CLAide::Help
+    end
   end
 end