Fix repo lint for path arguments

lib/cocoapods/command/repo/lint.rb

@@ -35,16 +35,20 @@ module Pod
         #
         def run
           if @name
-            sources = SourcesManager.sources([@name])
+            if File.exist?(@name)
+              sources = [Pathname.new(@name)]
             else
-            sources = SourcesManager.aggregate.sources
+              sources = SourcesManager.sources([@name]).map(&:repo)
+            end
+          else
+            sources = SourcesManager.aggregate.sources.map(&:repo)
           end
 
           sources.each do |source|
-            SourcesManager.check_version_information(source.repo)
-            UI.puts "\nLinting spec repo `#{source.repo.basename}`\n".yellow
+            SourcesManager.check_version_information(source)
+            UI.puts "\nLinting spec repo `#{source.basename}`\n".yellow
 
-            validator = Source::HealthReporter.new(source.repo)
+            validator = Source::HealthReporter.new(source)
             validator.pre_check do |_name, _version|
               UI.print '.'
             end

spec/functional/command/repo/lint_spec.rb

@@ -17,6 +17,12 @@ module Pod
       lambda { run_command('repo', 'lint', repo) }.should.not.raise
     end
 
+    it 'lints a repository by relative path' do
+      repo = fixture('spec-repos/test_repo')
+      repo = repo.relative_path_from(SpecHelper.temporary_directory).to_s
+      lambda { run_command('repo', 'lint', repo) }.should.not.raise
+    end
+
     it 'raises when there is no repository with given name' do
       repo = fixture('spec-repos/not_existing_repo').to_s
       e = lambda { run_command('repo', 'lint', repo) }.should.raise Informative