`hub help hub`

lib/hub/commands.rb

@@ -145,9 +145,13 @@ module Hub
     # $ hub help
     # (print improved help text)
     def help(args)
-      return if args.size > 1
-      puts improved_help_text
-      exit
+      if args[1] == 'hub'
+        puts hub_manpage
+        exit
+      elsif args.size == 1
+        puts improved_help_text
+        exit
+      end
     end
 
     # The text print when `hub help` is run, kept in its own method
@@ -208,6 +212,49 @@ help
       end
     end
 
+    # Returns the terminal-formatted manpage, ready to be printed to
+    # the screen.
+    def hub_manpage
+      return "** Can't find groff(1)" unless groff?
+
+      require 'open3'
+      out = nil
+      Open3.popen3(groff_command) do |stdin, stdout, _|
+        stdin.puts hub_raw_manpage
+        stdin.close
+        out = stdout.read.strip
+      end
+      out
+    end
+
+    # Returns true if groff is installed and in our path, false if
+    # not.
+    def groff?
+      system("which groff")
+    end
+
+    # The groff command complete with crazy arguments we need to run
+    # in order to turn our raw roff (manpage markup) into something
+    # readable on the terminal.
+    def groff_command
+      "groff -Wall -mtty-char -mandoc -Tascii"
+    end
+
+    # Returns the raw hub manpage. If we're not running in standalone
+    # mode, it's a file sitting at the root under the `man`
+    # directory.
+    #
+    # If we are running in standalone mode the manpage will be
+    # included after the __END__ of the file so we can grab it using
+    # DATA.
+    def hub_raw_manpage
+      if File.exists? file = File.dirname(__FILE__) + '/../../man/hub.1'
+        File.read(file)
+      else
+        DATA.read
+      end
+    end
+
     # All calls to `puts` in after hooks or commands are paged,
     # git-style.
     def puts(*args)

test/hub_test.rb

@@ -97,4 +97,26 @@ class HubTest < Test::Unit::TestCase
   def test_help_by_default
     assert_equal Hub::Commands.improved_help_text, hub("")
   end
+
+  def test_help_hub
+    help_manpage = hub("help hub")
+    assert_includes "git + hub = github", help_manpage
+    assert_includes "Writes shell aliasing code for", help_manpage
+    assert_includes "Chris Wanstrath :: chris@ozmm.org", help_manpage
+    puts help_manpage
+    assert_includes <<-config, help_manpage
+       Use git-config(1) to display the currently configured GitHub username:
+
+           $ git config --global github.user
+config
+  end
+
+  def test_help_hub_no_groff
+    help_manpage = hub("help hub") do
+      Hub::Commands.class_eval do
+        def groff?; false end
+      end
+    end
+    assert_equal "** Can't find groff(1)\n", help_manpage
+  end
 end