genshi/mirror: markup/template.py comparison

comparison markup/template.py @ 53:512eb72dbb19 trunk

* Add helper function to let directives apply any remaining directives, and use that helper consistently in every directive. * Fix the order of the `py:choose`, `py:when`, and `py:otherwise` directives. * Moved some of the `py:choose` tests to a new `unittest` suite to keep the docstring compact.

author	cmlenz
date	Tue, 04 Jul 2006 11:57:08 +0000
parents	b2383634ec04
children	1f3cd91325d9

comparison

equal deleted inserted replaced

-:1340e3297d19
+:512eb72dbb19
 __slots__ = ['expr']
 def __init__(self, value):
 self.expr = value and Expression(value) or None
-def __call__(self, stream, ctxt, directives=None):
+def __call__(self, stream, ctxt, directives):
 raise NotImplementedError
 def __repr__(self):
 expr = ''
 if self.expr is not None:
 expr = ' "%s"' % self.expr.source
 return '<%s%s>' % (self.__class__.__name__, expr)
+def _apply_directives(self, stream, ctxt, directives):
+if directives:
+stream = directives[0](iter(stream), ctxt, directives[1:])
+return stream
 class AttrsDirective(Directive):
 """Implementation of the `py:attrs` template directive.
 <li>Bar</li>
 </ul>
 """
 __slots__ = []
-def __call__(self, stream, ctxt, directives=None):
+def __call__(self, stream, ctxt, directives):
-kind, (tag, attrib), pos  = stream.next()
+def _generate():
-attrs = self.expr.evaluate(ctxt)
+kind, (tag, attrib), pos  = stream.next()
-if attrs:
+attrs = self.expr.evaluate(ctxt)
-attrib = Attributes(attrib[:])
+if attrs:
-if not isinstance(attrs, list): # assume it's a dict
+attrib = Attributes(attrib[:])
-attrs = attrs.items()
+if not isinstance(attrs, list): # assume it's a dict
-for name, value in attrs:
+attrs = attrs.items()
-if value is None:
+for name, value in attrs:
-attrib.remove(name)
+if value is None:
-else:
+attrib.remove(name)
-attrib.set(name, unicode(value).strip())
+else:
-yield kind, (tag, attrib), pos
+attrib.set(name, unicode(value).strip())
-for event in stream:
+yield kind, (tag, attrib), pos
-yield event
+for event in stream:
+yield event
+return self._apply_directives(_generate(), ctxt, directives)
 class ContentDirective(Directive):
 """Implementation of the `py:content` template directive.
 </ul>
 """
 __slots__ = []
 def __call__(self, stream, ctxt, directives):
-def generate():
+def _generate():
 kind, data, pos = stream.next()
 if kind is Stream.START:
 yield kind, data, pos # emit start tag
 yield Template.EXPR, self.expr, pos
 previous = stream.next()
 for event in stream:
 previous = event
 if previous is not None:
 yield previous
-output = generate()
+return self._apply_directives(_generate(), ctxt, directives)
-if directives:
-output = directives[0](output, ctxt, directives[1:])
-return output
 class DefDirective(Directive):
 """Implementation of the `py:def` template directive.
 if args:
 scope[name] = args.pop(0)
 else:
 scope[name] = kwargs.pop(name, self.defaults.get(name))
 ctxt.push(**scope)
-stream = iter(self.stream)
+stream = self._apply_directives(self.stream, ctxt, self.directives)
-if self.directives:
-stream = self.directives[0](stream, ctxt, self.directives[1:])
 for event in stream:
 yield event
 ctxt.pop()
 targets, value = value.split(' in ', 1)
 self.targets = [str(name.strip()) for name in targets.split(',')]
 Directive.__init__(self, value)
 def __call__(self, stream, ctxt, directives):
-iterable = self.expr.evaluate(ctxt) or []
+iterable = self.expr.evaluate(ctxt)
 if iterable is not None:
 stream = list(stream)
 for item in iter(iterable):
 if len(self.targets) == 1:
 item = [item]
 scope = {}
 for idx, name in enumerate(self.targets):
 scope[name] = item[idx]
 ctxt.push(**scope)
-output = stream
+for event in self._apply_directives(stream, ctxt, directives):
-if directives:
-output = directives[0](iter(output), ctxt, directives[1:])
-for event in output:
 yield event
 ctxt.pop()
 def __repr__(self):
 return '<%s "%s in %s">' % (self.__class__.__name__,
 """
 __slots__ = []
 def __call__(self, stream, ctxt, directives):
 if self.expr.evaluate(ctxt):
-if directives:
+return self._apply_directives(stream, ctxt, directives)
-stream = directives[0](stream, ctxt, directives[1:])
-return stream
 return []
 class MatchDirective(Directive):
 """Implementation of the `py:match` template directive.
 def __call__(self, stream, ctxt, directives=None):
 if self.expr:
 strip = self.expr.evaluate(ctxt)
 else:
 strip = True
+stream = self._apply_directives(stream, ctxt, directives)
 if strip:
 stream.next() # skip start tag
 previous = stream.next()
 for event in stream:
 yield previous
 class ChooseDirective(Directive):
 """Implementation of the `py:choose` directive for conditionally selecting
 one of several body elements to display.
 If the `py:choose` expression is empty the expressions of nested `py:when`
 directives are tested for truth.  The first true `py:when` body is output.
+If no `py:when` directive is matched then the fallback directive
+`py:otherwise` will be used.
 >>> ctxt = Context()
 >>> tmpl = Template('''<div xmlns:py="http://purl.org/kid/ns#"
 ...   py:choose="">
 ...   <span py:when="0 == 1">0</span>
 ...   <span py:when="1 == 1">1</span>
+...   <span py:otherwise="">2</span>
 ... </div>''')
 >>> print tmpl.generate(ctxt)
 <div>
 <span>1</span>
 </div>
-If multiple `py:when` bodies match only the first is output.
->>> tmpl = Template('''<div xmlns:py="http://purl.org/kid/ns#"
-...   py:choose="">
-...   <span py:when="1 == 1">1</span>
-...   <span py:when="2 == 2">2</span>
-... </div>''')
->>> print tmpl.generate(ctxt)
-<div>
-<span>1</span>
-</div>
 If the `py:choose` directive contains an expression, the nested `py:when`
-directives are tested for equality to the `py:choose` expression.
+directives are tested for equality to the `py:choose` expression:
 >>> tmpl = Template('''<div xmlns:py="http://purl.org/kid/ns#"
 ...   py:choose="2">
 ...   <span py:when="1">1</span>
 ...   <span py:when="2">2</span>
 ... </div>''')
 >>> print tmpl.generate(ctxt)
 <div>
 <span>2</span>
 </div>
-If no `py:when` directive is matched then the fallback directive
-`py:otherwise` will be used.
->>> tmpl = Template('''<div xmlns:py="http://purl.org/kid/ns#"
-...   py:choose="">
-...   <span py:when="False">hidden</span>
-...   <span py:otherwise="">hello</span>
-... </div>''')
->>> print tmpl.generate(ctxt)
-<div>
-<span>hello</span>
-</div>
-`py:choose` blocks can be nested:
->>> tmpl = Template('''<div xmlns:py="http://purl.org/kid/ns#"
-...   py:choose="1">
-...   <div py:when="1" py:choose="3">
-...     <span py:when="2">2</span>
-...     <span py:when="3">3</span>
-...   </div>
-... </div>''')
->>> print tmpl.generate(ctxt)
-<div>
-<div>
-<span>3</span>
-</div>
-</div>
 Behavior is undefined if a `py:choose` block contains content outside a
 `py:when` or `py:otherwise` block.  Behavior is also undefined if a
 `py:otherwise` occurs before `py:when` blocks.
 """
 __slots__ = ['matched', 'value']
-def __call__(self, stream, ctxt, directives=None):
+def __call__(self, stream, ctxt, directives):
 if self.expr:
 self.value = self.expr.evaluate(ctxt)
 self.matched = False
 ctxt.push(_choose=self)
-for event in stream:
+for event in self._apply_directives(stream, ctxt, directives):
 yield event
 ctxt.pop()
 class WhenDirective(Directive):
 return []
 value = self.expr.evaluate(ctxt)
 try:
 if value == choose.value:
 choose.matched = True
-return stream
+return self._apply_directives(stream, ctxt, directives)
 except AttributeError:
 if value:
 choose.matched = True
-return stream
+return self._apply_directives(stream, ctxt, directives)
 return []
 class OtherwiseDirective(Directive):
 """Implementation of the `py:otherwise` directive for nesting in a parent
 def __call__(self, stream, ctxt, directives=None):
 choose = ctxt['_choose']
 if choose.matched:
 return []
 choose.matched = True
-return stream
+return self._apply_directives(stream, ctxt, directives)
 class Template(object):
 """Can parse a template and transform it into the corresponding output
 based on context data.
 directives = [('def', DefDirective),
 ('match', MatchDirective),
 ('for', ForDirective),
 ('if', IfDirective),
-('choose', ChooseDirective),
 ('when', WhenDirective),
 ('otherwise', OtherwiseDirective),
+('choose', ChooseDirective),
 ('replace', ReplaceDirective),
 ('content', ContentDirective),
 ('attrs', AttrsDirective),
 ('strip', StripDirective)]
 _dir_by_name = dict(directives)

Mercurial > genshi > mirror

comparison markup/template.py @ 53:512eb72dbb19 trunk