Teach python directive to include external files.

No unit tests yet, this is purely temporary, I hope to move to
pygments via ulif.rest's "sourcecode" directive.

atomat/rst2entry.py

@@ -1,4 +1,6 @@
+import os
 from docutils.core import publish_string
+from docutils import utils
 from xml.dom import minidom
 import xml.dom
 import email.Utils
@@ -11,13 +13,41 @@
 
 def python(name, arguments, options, content, lineno,
            content_offset, block_text, state, state_machine):
-    inp = StringIO('\n'.join(content).encode('utf-8'))
+    filename = options.get('filename', None)
+    if filename is None:
+        inp = StringIO('\n'.join(content).encode('utf-8'))
+    else:
+        source = state_machine.input_lines.source(
+            lineno - state_machine.input_offset - 1)
+        source_dir = os.path.dirname(os.path.abspath(source))
+        filename = os.path.normpath(os.path.join(source_dir, filename))
+        filename = utils.relative_path(None, filename)
+        state.document.settings.record_dependencies.add(filename)
+        inp = file(filename)
     outp = StringIO()
-    outp.write('<div class="py-listing">')
     htmlizer.filter(inp, outp, writer=htmlizer.SmallerHTMLWriter)
-    outp.write('</div>')
     html = outp.getvalue()
-    return [nodes.raw('', html, format='html')]
+
+    if arguments:
+        title_text = arguments[0]
+        text_nodes, messages = state.inline_text(title_text, lineno)
+        title = nodes.caption('', '# ', *text_nodes)
+    else:
+        messages = []
+        title = None
+
+    fig = nodes.figure('')
+    fig['classes'].append('py-listing')
+    if title is not None:
+        fig += title
+
+    fig += nodes.raw('', html, format='html')
+
+    return [fig] + messages
+
+python.arguments = (0, 1, True)
+python.options = dict(filename=rst.directives.path,
+                      )
 python.content = 1
 
 rst.directives.register_directive('python', python)