diff --git a/lib/git/base.rb b/lib/git/base.rb
index ad3e52ec..1f554e25 100644
--- a/lib/git/base.rb
+++ b/lib/git/base.rb
@@ -26,7 +26,7 @@ def self.bare(git_dir, opts = {})
     #
     def self.clone(repository, name, opts = {})
       # run git-clone 
-      self.new(Git::Lib.new.clone(repository, name, opts))
+      self.new(Git::Lib.new(env: opts.delete(:env)).clone(repository, name, opts))
     end
     
     # Returns (and initialize if needed) a Git::Config instance
@@ -75,6 +75,8 @@ def self.open(working_dir, opts={})
       self.new({:working_directory => working_dir}.merge(opts))
     end
     
+    attr_reader :env
+    
     def initialize(options = {})
       if working_dir = options[:working_directory]
         options[:repository] ||= File.join(working_dir, '.git')
@@ -90,6 +92,7 @@ def initialize(options = {})
       @working_directory = options[:working_directory] ? Git::WorkingDirectory.new(options[:working_directory]) : nil
       @repository = options[:repository] ? Git::Repository.new(options[:repository]) : nil 
       @index = options[:index] ? Git::Index.new(options[:index], false) : nil
+      @env = (options[:env] || {}).freeze
     end
     
     # changes current working directory for a block
diff --git a/lib/git/lib.rb b/lib/git/lib.rb
index 777e42ea..4972be90 100644
--- a/lib/git/lib.rb
+++ b/lib/git/lib.rb
@@ -19,11 +19,14 @@ def initialize(base = nil, logger = nil)
         @git_dir = base.repo.path
         @git_index_file = base.index.path if base.index
         @git_work_dir = base.dir.path if base.dir
+        @git_extra_env = base.env
       elsif base.is_a?(Hash)
         @git_dir = base[:repository]
         @git_index_file = base[:index]
         @git_work_dir = base[:working_directory]
+        @git_extra_env = base[:env].freeze
       end
+      @git_extra_env ||= {}.freeze
       @logger = logger
     end
 
@@ -64,6 +67,7 @@ def clone(repository, name, opts = {})
       arr_opts << '--bare' if opts[:bare]
       arr_opts << '--branch' << opts[:branch] if opts[:branch]
       arr_opts << '--depth' << opts[:depth].to_i if opts[:depth] && opts[:depth].to_i > 0
+      arr_opts << '--no-single-branch' if opts[:no_single_branch]
       arr_opts << '--config' << opts[:config] if opts[:config]
       arr_opts << '--origin' << opts[:remote] || opts[:origin] if opts[:remote] || opts[:origin]
       arr_opts << '--recursive' if opts[:recursive]
@@ -75,7 +79,7 @@ def clone(repository, name, opts = {})
 
       command('clone', arr_opts)
 
-      opts[:bare] ? {:repository => clone_dir} : {:working_directory => clone_dir}
+      opts[:bare] ? {:repository => clone_dir} : {:working_directory => clone_dir, :env => @git_extra_env}
     end
 
 
@@ -577,6 +581,7 @@ def revert(commitish, opts = {})
 
       arr_opts = []
       arr_opts << '--no-edit' if opts[:no_edit]
+      arr_opts << '--no-commit' if opts[:no_commit]
       arr_opts << commitish
 
       command('revert', arr_opts)
@@ -725,8 +730,10 @@ def tag(name, *opts)
 
     def fetch(remote, opts)
       arr_opts = [remote]
+      arr_opts << opts[:refs] if opts[:refs]
       arr_opts << '--tags' if opts[:t] || opts[:tags]
       arr_opts << '--prune' if opts[:p] || opts[:prune]
+      arr_opts << '--unshallow' if opts[:unshallow]
 
       command('fetch', arr_opts)
     end
@@ -850,7 +857,7 @@ def meets_required_version?
     end
 
 
-    private
+    protected
 
     # Systen ENV variables involved in the git commands.
     #
@@ -869,14 +876,14 @@ def command_lines(cmd, opts = [], chdir = true, redirect = '')
     # Takes the current git's system ENV variables and store them.
     def store_git_system_env_variables
       @git_system_env_variables = {}
-      ENV_VARIABLE_NAMES.each do |env_variable_name|
+      (ENV_VARIABLE_NAMES + @git_extra_env.keys).each do |env_variable_name|
         @git_system_env_variables[env_variable_name] = ENV[env_variable_name]
       end
     end
 
     # Takes the previously stored git's ENV variables and set them again on ENV.
     def restore_git_system_env_variables
-      ENV_VARIABLE_NAMES.each do |env_variable_name|
+      (ENV_VARIABLE_NAMES + @git_extra_env.keys).each do |env_variable_name|
         ENV[env_variable_name] = @git_system_env_variables[env_variable_name]
       end
     end
@@ -887,6 +894,9 @@ def set_custom_git_env_variables
       ENV['GIT_WORK_TREE'] = @git_work_dir
       ENV['GIT_INDEX_FILE'] = @git_index_file
       ENV['GIT_SSH'] = Git::Base.config.git_ssh
+      @git_extra_env.each do |k, v|
+        ENV[k] = v
+      end
     end
 
     # Runs a block inside an environment with customized ENV variables.