added loop filtering
--HG--
branch : trunk
diff --git a/jinja2/compiler.py b/jinja2/compiler.py
index e692184..e16617e 100644
--- a/jinja2/compiler.py
+++ b/jinja2/compiler.py
@@ -29,6 +29,14 @@
}
+try:
+ exec '(0 if 0 else 0)'
+except SyntaxError:
+ have_condexpr = False
+else:
+ have_condexpr = True
+
+
def generate(node, environment, filename, stream=None):
"""Generate the python source for a node tree."""
is_child = node.find(nodes.Extends) is not None
@@ -114,6 +122,7 @@
self.rootlevel = False
self.parent = parent
self.buffer = None
+ self.name_overrides = {}
self.block = parent and parent.block or None
if parent is not None:
self.identifiers.declared.update(
@@ -122,11 +131,13 @@
parent.identifiers.declared_parameter
)
self.buffer = parent.buffer
+ self.name_overrides = parent.name_overrides.copy()
def copy(self):
"""Create a copy of the current one."""
rv = copy(self)
rv.identifiers = copy(self.identifiers)
+ rv.name_overrides = self.name_overrides.copy()
return rv
def inspect(self, nodes, hard_scope=False):
@@ -516,21 +527,62 @@
aliases = self.collect_shadowed(loop_frame)
self.pull_locals(loop_frame, True)
-
- self.newline(node)
if node.else_:
self.writeline('l_loop = None')
- self.write('for ')
+
+ self.newline(node)
+ self.writeline('for ')
self.visit(node.target, loop_frame)
self.write(extended_loop and ', l_loop in LoopContext(' or ' in ')
- self.visit(node.iter, loop_frame)
+
+ # the expression pointing to the parent loop. We make the
+ # undefined a bit more debug friendly at the same time.
+ parent_loop = 'loop' in aliases and aliases['loop'] \
+ or "Undefined('loop', extra=%r)" % \
+ 'the filter section of a loop as well as the ' \
+ 'else block doesn\'t have access to the special ' \
+ "'loop' variable of the current loop. Because " \
+ 'there is no parent loop it\'s undefined.'
+
+ # if we have an extened loop and a node test, we filter in the
+ # "outer frame".
+ if extended_loop and node.test is not None:
+ self.write('(')
+ self.visit(node.target, loop_frame)
+ self.write(' for ')
+ self.visit(node.target, loop_frame)
+ self.write(' in ')
+ self.visit(node.iter, loop_frame)
+ self.write(' if (')
+ test_frame = loop_frame.copy()
+ test_frame.name_overrides['loop'] = parent_loop
+ self.visit(node.test, test_frame)
+ self.write('))')
+
+ else:
+ self.visit(node.iter, loop_frame)
+
if 'loop' in aliases:
self.write(', ' + aliases['loop'])
self.write(extended_loop and '):' or ':')
+
+ # tests in not extended loops become a continue
+ if not extended_loop and node.test is not None:
+ self.indent()
+ self.writeline('if ')
+ self.visit(node.test)
+ self.write(':')
+ self.indent()
+ self.writeline('continue')
+ self.outdent(2)
+
self.blockvisit(node.body, loop_frame)
if node.else_:
self.writeline('if l_loop is None:')
+ self.indent()
+ self.writeline('l_loop = ' + parent_loop)
+ self.outdent()
self.blockvisit(node.else_, loop_frame)
# reset the aliases if there are any.
@@ -667,7 +719,7 @@
self.write('%s.append(' % frame.buffer)
self.write(finalizer + '(')
self.visit(item, frame)
- self.write(')' * (1 + frame.buffer is not None))
+ self.write(')' * (1 + (frame.buffer is not None)))
# otherwise we create a format string as this is faster in that case
else:
@@ -721,8 +773,14 @@
self.writeline('context[%r] = l_%s' % (name, name))
def visit_Name(self, node, frame):
- if frame.toplevel and node.ctx == 'store':
- frame.assigned_names.add(node.name)
+ if node.ctx == 'store':
+ if frame.toplevel:
+ frame.assigned_names.add(node.name)
+ frame.name_overrides.pop(node.name, None)
+ elif node.ctx == 'load':
+ if node.name in frame.name_overrides:
+ self.write(frame.name_overrides[node.name])
+ return
self.write('l_' + node.name)
def visit_Const(self, node, frame):
@@ -856,6 +914,24 @@
self.signature(node, frame)
self.write(')')
+ def visit_CondExpr(self, node, frame):
+ if not have_condexpr:
+ self.write('((')
+ self.visit(node.test, frame)
+ self.write(') and (')
+ self.visit(node.expr1, frame)
+ self.write(',) or (')
+ self.visit(node.expr2, frame)
+ self.write(',))[0]')
+ else:
+ self.write('(')
+ self.visit(node.expr1, frame)
+ self.write(' if ')
+ self.visit(node.test, frame)
+ self.write(' else ')
+ self.visit(node.expr2, frame)
+ self.write(')')
+
def visit_Call(self, node, frame, extra_kwargs=None):
self.visit(node.node, frame)
self.write('(')
diff --git a/jinja2/nodes.py b/jinja2/nodes.py
index e1857d2..89c6fa2 100644
--- a/jinja2/nodes.py
+++ b/jinja2/nodes.py
@@ -207,7 +207,7 @@
class For(Stmt):
"""A node that represents a for loop"""
- fields = ('target', 'iter', 'body', 'else_', 'recursive')
+ fields = ('target', 'iter', 'body', 'else_', 'test')
class If(Stmt):
diff --git a/jinja2/optimizer.py b/jinja2/optimizer.py
index d2550f4..5877c6f 100644
--- a/jinja2/optimizer.py
+++ b/jinja2/optimizer.py
@@ -131,6 +131,9 @@
# we also don't want unrolling if macros are defined in it
if node.find(nodes.Macro) is not None:
raise TypeError()
+ # XXX: add support for loop test clauses in the optimizer
+ if node.test is not None:
+ raise TypeError()
except (nodes.Impossible, TypeError):
return self.generic_visit(node, context)
@@ -156,7 +159,7 @@
try:
try:
- for loop, item in LoopContext(iterable, parent, True):
+ for item, loop in LoopContext(iterable, parent, True):
context['loop'] = loop.make_static()
assign(node.target, item)
result.extend(self.visit(n.copy(), context)
diff --git a/jinja2/parser.py b/jinja2/parser.py
index 2d04211..5185df3 100644
--- a/jinja2/parser.py
+++ b/jinja2/parser.py
@@ -110,18 +110,17 @@
self.filename)
target.set_ctx('store')
self.stream.expect('in')
- iter = self.parse_tuple()
- if self.stream.current.type is 'recursive':
+ iter = self.parse_tuple(no_condexpr=True)
+ test = None
+ if self.stream.current.type is 'if':
self.stream.next()
- recursive = True
- else:
- recursive = False
+ test = self.parse_expression()
body = self.parse_statements(('endfor', 'else'))
if self.stream.next().type is 'endfor':
else_ = []
else:
else_ = self.parse_statements(('endfor',), drop_needle=True)
- return nodes.For(target, iter, body, else_, False, lineno=lineno)
+ return nodes.For(target, iter, body, else_, test, lineno=lineno)
def parse_if(self):
"""Parse an if construct."""
@@ -236,8 +235,10 @@
self.end_statement()
return node
- def parse_expression(self):
+ def parse_expression(self, no_condexpr=False):
"""Parse an expression."""
+ if no_condexpr:
+ return self.parse_or()
return self.parse_condexpr()
def parse_condexpr(self):
@@ -417,14 +418,19 @@
node = self.parse_postfix(node)
return node
- def parse_tuple(self, enforce=False, simplified=False):
+ def parse_tuple(self, enforce=False, simplified=False, no_condexpr=False):
"""
Parse multiple expressions into a tuple. This can also return
just one expression which is not a tuple. If you want to enforce
a tuple, pass it enforce=True (currently unused).
"""
lineno = self.stream.current.lineno
- parse = simplified and self.parse_primary or self.parse_expression
+ if simplified:
+ parse = self.parse_primary
+ elif no_condexpr:
+ parse = lambda: self.parse_expression(no_condexpr=True)
+ else:
+ parse = self.parse_expression
args = []
is_tuple = False
while 1:
diff --git a/jinja2/runtime.py b/jinja2/runtime.py
index 238d4cf..676c1f5 100644
--- a/jinja2/runtime.py
+++ b/jinja2/runtime.py
@@ -25,7 +25,7 @@
except (AttributeError, UnicodeError):
try:
return obj[argument]
- except LookupError:
+ except (TypeError, LookupError):
return Undefined(obj, argument)
@@ -138,8 +138,9 @@
def __init__(self, iterable, parent=None, enforce_length=False):
self._iterable = iterable
+ self._next = iter(iterable).next
self._length = None
- self.index0 = 0
+ self.index0 = -1
self.parent = parent
if enforce_length:
len(self)
@@ -152,9 +153,11 @@
return StaticLoopContext(self.index0, self.length, parent)
def __iter__(self):
- for item in self._iterable:
- yield self, item
- self.index0 += 1
+ return self
+
+ def next(self):
+ self.index0 += 1
+ return self._next(), self
def __len__(self):
if self._length is None:
@@ -162,7 +165,8 @@
length = len(self._iterable)
except TypeError:
self._iterable = tuple(self._iterable)
- length = self.index0 + len(tuple(self._iterable))
+ self._next = iter(self._iterable).next
+ length = len(tuple(self._iterable)) + self.index0 + 1
self._length = length
return self._length
@@ -217,12 +221,13 @@
try:
value = self.defaults[idx - arg_count]
except IndexError:
- value = Undefined(name)
+ value = Undefined(name, extra='parameter not provided')
arguments['l_' + name] = value
if self.caller:
caller = kwargs.pop('caller', None)
if caller is None:
- caller = Undefined('caller')
+ caller = Undefined('caller', extra='The macro was called '
+ 'from an expression and not a call block.')
arguments['l_caller'] = caller
if self.catch_all:
arguments['l_arguments'] = kwargs
@@ -238,14 +243,14 @@
class Undefined(object):
"""The object for undefined values."""
- def __init__(self, name=None, attr=None):
+ def __init__(self, name=None, attr=None, extra=None):
if attr is None:
self._undefined_hint = '%r is undefined' % name
- elif name is None:
- self._undefined_hint = 'attribute %r is undefined' % name
else:
self._undefined_hint = 'attribute %r of %r is undefined' \
% (attr, name)
+ if extra is not None:
+ self._undefined_hint += ' (' + extra + ')'
def fail(self, *args, **kwargs):
raise TypeError(self._undefined_hint)
diff --git a/test_loop_filter.py b/test_loop_filter.py
new file mode 100644
index 0000000..64f32d3
--- /dev/null
+++ b/test_loop_filter.py
@@ -0,0 +1,12 @@
+from jinja2 import Environment
+
+tmpl = Environment().from_string("""\
+<ul>
+{% for item in [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] if item % 2 == 0 %}
+ <li>{{ loop.index }} / {{ loop.length }}: {{ item }}</li>
+{% endfor %}
+</ul>
+{{ 1 if foo else 0 }}
+""")
+
+print tmpl.render(foo=True)