old_contents: import os
  import sys
  import os.path as op
  import shutil
  
  from invoke import task
  from ._config import DOC_DIR, DOC_BUILD_DIR
  
  
  @task(help=dict(clean='clear the doc output; start fresh',
                  build='build html docs',
                  show='show the docs in the browser.'))
  def docs(ctx, clean=False, build=False, show=False, **kwargs):
      """ make API documentation
      """
      # Prepare
      
      if not (clean or build or show):
          sys.exit('Task "docs" must be called with --clean, --build or --show')
      
      if clean:
          sphinx_clean(DOC_BUILD_DIR)
      
      if build:
          sphinx_build(DOC_DIR, DOC_BUILD_DIR)
      
      if show:
          sphinx_show(os.path.join(DOC_BUILD_DIR, 'html'))
  
  
  def sphinx_clean(build_dir):
      if op.isdir(build_dir):
          shutil.rmtree(build_dir)
      os.mkdir(build_dir)
      print('Cleared build directory.')
  
  
  def sphinx_build(src_dir, build_dir):
      import sphinx
      ret = sphinx.build_main(['sphinx-build',  # Dummy
                               '-b', 'html',
                               '-d', op.join(build_dir, 'doctrees'),
                               src_dir,  # Source
                               op.join(build_dir, 'html'),  # Dest
                               ])
      if ret != 0:
          raise RuntimeError('Sphinx error: %s' % ret)
      print("Build finished. The HTML pages are in %s/html." % build_dir)
  
  
  def sphinx_show(html_dir):
      index_html = op.join(html_dir, 'index.html')
      if not op.isfile(index_html):
          sys.exit('Cannot show pages, build the html first.')
      import webbrowser
      webbrowser.open_new_tab(index_html)
  
new_contents: import os
  import sys
  import os.path as op
  import shutil
  
  from invoke import task
  from ._config import DOC_DIR, DOC_BUILD_DIR
  
  
  @task(help=dict(clean='clear the doc output; start fresh',
                  build='build html docs',
                  show='show the docs in the browser.'))
  def docs(ctx, clean=False, build=False, show=False, **kwargs):
      """ make API documentation
      """
      # Prepare
      
      if not (clean or build or show):
          sys.exit('Task "docs" must be called with --clean, --build or --show')
      
      if clean:
          sphinx_clean(DOC_BUILD_DIR)
      
      if build:
          sphinx_build(DOC_DIR, DOC_BUILD_DIR)
      
      if show:
          sphinx_show(os.path.join(DOC_BUILD_DIR, 'html'))
  
  
  def sphinx_clean(build_dir):
      if op.isdir(build_dir):
          shutil.rmtree(build_dir)
      os.mkdir(build_dir)
      print('Cleared build directory.')
  
  
  def sphinx_build(src_dir, build_dir):
      import sphinx
      cmd = [ '-b', 'html',
              '-d', op.join(build_dir, 'doctrees'),
              src_dir,  # Source
              op.join(build_dir, 'html'),  # Dest
              ]
      
      if sphinx.version_info > (1, 7):
          ret = sphinx.cmd.build.build_main(cmd)
      else:
          ret = sphinx.build_main(['sphinx-build'] + cmd)
      if ret != 0:
          raise RuntimeError('Sphinx error: %s' % ret)
      print("Build finished. The HTML pages are in %s/html." % build_dir)
  
  
  def sphinx_show(html_dir):
      index_html = op.join(html_dir, 'index.html')
      if not op.isfile(index_html):
          sys.exit('Cannot show pages, build the html first.')
      import webbrowser
      webbrowser.open_new_tab(index_html)
  
subject: update for new sphinx