add improved help

bin/hub

@@ -139,6 +139,93 @@ class Hub
       end
     end
     alias_method "--version", :version
+
+    # $ hub help
+    # (print improved help text)
+    def help(args)
+      return if args.size > 1
+      puts improved_help_text
+      exit
+    end
+
+    # The text print when `hub help` is run, kept in its own method
+    # for the convenience of the author.
+    def improved_help_text
+      <<-help
+usage: git [--version] [--exec-path[=GIT_EXEC_PATH]] [--html-path]
+    [-p|--paginate|--no-pager] [--bare] [--git-dir=GIT_DIR]
+    [--work-tree=GIT_WORK_TREE] [--help] COMMAND [ARGS]
+
+Creating a git repository:
+   clone      Clone a repository into a new directory
+   init       Create an empty git repository or reinitialize an existing one
+
+Working with content:
+   add        Add file contents to the index
+   branch     List, create, or delete branches
+   checkout   Checkout a branch or paths to the working tree
+   commit     Record changes to the repository
+   diff       Show changes between commits, commit and working tree, etc
+   log        Show commit logs
+   merge      Join two or more development histories together
+   mv         Move or rename a file, a directory, or a symlink
+   rm         Remove files from the working tree and from the index
+   status     Show the working tree status
+   show       Show various types of objects
+   tag        Create, list, delete or verify a tag object signed with GPG
+
+Over the network:
+   fetch      Download objects and refs from another repository
+   pull       Fetch from and merge with another repository or a local branch
+   push       Update remote refs along with associated objects
+   remote     Manage a set of tracked repositories
+
+Advanced commands:
+   bisect     Find by binary search the change that introduced a bug
+   grep       Print lines matching a pattern
+   reset      Reset current HEAD to the specified state
+   rebase     Forward-port local commits to the updated upstream head
+
+See 'git help COMMAND' for more information on a specific command.
+help
+    end
+
+    # All calls to `puts` in after hooks or commands are paged,
+    # git-style.
+    def puts(content)
+      page_stdout
+      super
+    end
+
+    # http://nex-3.com/posts/73-git-style-automatic-paging-in-ruby
+    def page_stdout
+      return if PLATFORM =~ /win32/
+      return unless $stdout.tty?
+
+      read, write = IO.pipe
+
+      if Kernel.fork
+        # Parent process, become pager
+        $stdin.reopen(read)
+        read.close
+        write.close
+
+        # Don't page if the input is short enough
+        ENV['LESS'] = 'FSRX'
+
+        # Wait until we have input before we start the pager
+        Kernel.select [STDIN]
+
+        pager = ENV['PAGER'] || 'less'
+        exec pager rescue exec "/bin/sh", "-c", pager
+      else
+        # Child process
+        $stdout.reopen(write)
+        $stderr.reopen(write) if $stderr.tty?
+        read.close
+        write.close
+      end
+    end
   end
 end
 

test/hub_test.rb

@@ -81,4 +81,12 @@ class HubTest < Test::Unit::TestCase
     h = hub("--version")
     assert_equal "git version 1.6.4.2\nhub version 0.1.0\n", h
   end
+
+  def test_help
+    assert_equal Hub::Commands.improved_help_text, hub("help")
+  end
+
+  def test_help_by_default
+    assert_equal Hub::Commands.improved_help_text, hub("")
+  end
 end