scm: git: add new method 'scm_cmd' to wrap shellout.

Refer Mercurial adapter r4830.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@4886 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/redmine/scm/adapters/git_adapter.rb

@@ -24,6 +24,9 @@ module Redmine
         # Git executable name
         GIT_BIN = Redmine::Configuration['scm_git_command'] || "git"
 
+        # raised if scm command exited with error, e.g. unknown revision.
+        class ScmCommandAborted < CommandFailed; end
+
         class << self
           def client_command
             @@bin    ||= GIT_BIN
@@ -300,6 +303,19 @@ module Redmine
             identifier[0,8]
           end
         end
+
+        def scm_cmd(*args, &block)
+          repo_path = root_url || url
+          full_args = [GIT_BIN, '--git-dir', repo_path]
+          full_args += args
+          full_args << '--no-color'
+          ret = shellout(full_args.map { |e| shell_quote e.to_s }.join(' '), &block)
+          if $? && $?.exitstatus != 0
+            raise ScmCommandAborted, "git exited with non-zero status: #{$?.exitstatus}"
+          end
+          ret
+        end
+        private :scm_cmd
       end
     end
   end