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# mako/parsetree.py
# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file>
#
# This module is part of Mako and is released under
"""defines the parse tree components for Mako templates."""
import re
from mako import ast
from mako import compat
from mako import exceptions
from mako import filters
from mako import util
class Node(object):
"""base class for a Node in the parse tree."""
def __init__(self, source, lineno, pos, filename):
self.source = source
self.lineno = lineno
self.pos = pos
self.filename = filename
@property
def exception_kwargs(self):
return {
"source": self.source,
"lineno": self.lineno,
"pos": self.pos,
"filename": self.filename,
}
def get_children(self):
return []
def accept_visitor(self, visitor):
def traverse(node):
for n in node.get_children():
n.accept_visitor(visitor)
method = getattr(visitor, "visit" + self.__class__.__name__, traverse)
method(self)
class TemplateNode(Node):
"""a 'container' node that stores the overall collection of nodes."""
def __init__(self, filename):
super(TemplateNode, self).__init__("", 0, 0, filename)
self.nodes = []
self.page_attributes = {}
def get_children(self):
return self.nodes
def __repr__(self):
return "TemplateNode(%s, %r)" % (
util.sorted_dict_repr(self.page_attributes),
self.nodes,
)
class ControlLine(Node):
"""defines a control line, a line-oriented python line or end tag.
e.g.::
% if foo:
(markup)
% endif
"""
has_loop_context = False
def __init__(self, keyword, isend, text, **kwargs):
super(ControlLine, self).__init__(**kwargs)
self.text = text
self.keyword = keyword
self.isend = isend
self.is_primary = keyword in ["for", "if", "while", "try", "with"]
self.nodes = []
if self.isend:
self._declared_identifiers = []
self._undeclared_identifiers = []
else:
code = ast.PythonFragment(text, **self.exception_kwargs)
self._declared_identifiers = code.declared_identifiers
self._undeclared_identifiers = code.undeclared_identifiers
def get_children(self):
return self.nodes
def declared_identifiers(self):
return self._declared_identifiers
def undeclared_identifiers(self):
return self._undeclared_identifiers
def is_ternary(self, keyword):
"""return true if the given keyword is a ternary keyword
for this ControlLine"""
return keyword in {
"if": set(["else", "elif"]),
"try": set(["except", "finally"]),
"for": set(["else"]),
}.get(self.keyword, [])
def __repr__(self):
return "ControlLine(%r, %r, %r, %r)" % (
self.keyword,
self.text,
self.isend,
(self.lineno, self.pos),
)
class Text(Node):
"""defines plain text in the template."""
def __init__(self, content, **kwargs):
super(Text, self).__init__(**kwargs)
self.content = content
def __repr__(self):
return "Text(%r, %r)" % (self.content, (self.lineno, self.pos))
class Code(Node):
"""defines a Python code block, either inline or module level.
e.g.::
inline:
<%
x = 12
%>
module level:
<%!
import logger
%>
"""
def __init__(self, text, ismodule, **kwargs):
super(Code, self).__init__(**kwargs)
self.text = text
self.ismodule = ismodule
self.code = ast.PythonCode(text, **self.exception_kwargs)
def declared_identifiers(self):
return self.code.declared_identifiers
def undeclared_identifiers(self):
return self.code.undeclared_identifiers
def __repr__(self):
return "Code(%r, %r, %r)" % (
self.text,
self.ismodule,
(self.lineno, self.pos),
)
class Comment(Node):
"""defines a comment line.
# this is a comment
"""
def __init__(self, text, **kwargs):
super(Comment, self).__init__(**kwargs)
self.text = text
def __repr__(self):
return "Comment(%r, %r)" % (self.text, (self.lineno, self.pos))
class Expression(Node):
"""defines an inline expression.
${x+y}
"""
def __init__(self, text, escapes, **kwargs):
super(Expression, self).__init__(**kwargs)
self.text = text
self.escapes = escapes
self.escapes_code = ast.ArgumentList(escapes, **self.exception_kwargs)
self.code = ast.PythonCode(text, **self.exception_kwargs)
def declared_identifiers(self):
return []
def undeclared_identifiers(self):
# TODO: make the "filter" shortcut list configurable at parse/gen time
return self.code.undeclared_identifiers.union(
self.escapes_code.undeclared_identifiers.difference(
set(filters.DEFAULT_ESCAPES.keys())
)
).difference(self.code.declared_identifiers)
def __repr__(self):
return "Expression(%r, %r, %r)" % (
self.text,
self.escapes_code.args,
(self.lineno, self.pos),
)
class _TagMeta(type):
"""metaclass to allow Tag to produce a subclass according to
its keyword"""
_classmap = {}
def __init__(cls, clsname, bases, dict_):
if getattr(cls, "__keyword__", None) is not None:
cls._classmap[cls.__keyword__] = cls
super(_TagMeta, cls).__init__(clsname, bases, dict_)
def __call__(cls, keyword, attributes, **kwargs):
if ":" in keyword:
ns, defname = keyword.split(":")
return type.__call__(
CallNamespaceTag, ns, defname, attributes, **kwargs
)
try:
cls = _TagMeta._classmap[keyword]
except KeyError:
raise exceptions.CompileException(
"No such tag: '%s'" % keyword,
source=kwargs["source"],
lineno=kwargs["lineno"],
pos=kwargs["pos"],
filename=kwargs["filename"],
)
return type.__call__(cls, keyword, attributes, **kwargs)
class Tag(compat.with_metaclass(_TagMeta, Node)):
"""abstract base class for tags.
e.g.::
<%sometag/>
<%someothertag>
stuff
</%someothertag>
"""
__keyword__ = None
def __init__(
self,
keyword,
attributes,
expressions,
nonexpressions,
required,
**kwargs
):
r"""construct a new Tag instance.
this constructor not called directly, and is only called
by subclasses.
:param keyword: the tag keyword
:param attributes: raw dictionary of attribute key/value pairs
:param expressions: a set of identifiers that are legal attributes,
which can also contain embedded expressions
:param nonexpressions: a set of identifiers that are legal
attributes, which cannot contain embedded expressions
:param \**kwargs:
other arguments passed to the Node superclass (lineno, pos)
"""
super(Tag, self).__init__(**kwargs)
self.keyword = keyword
self.attributes = attributes
self._parse_attributes(expressions, nonexpressions)
missing = [r for r in required if r not in self.parsed_attributes]
if len(missing):
raise exceptions.CompileException(
"Missing attribute(s): %s"
% ",".join([repr(m) for m in missing]),
**self.exception_kwargs
)
self.parent = None
self.nodes = []
def is_root(self):
return self.parent is None
def get_children(self):
return self.nodes
def _parse_attributes(self, expressions, nonexpressions):
undeclared_identifiers = set()
self.parsed_attributes = {}
for key in self.attributes:
if key in expressions:
expr = []
for x in re.compile(r"(\${.+?})", re.S).split(
self.attributes[key]
):
m = re.compile(r"^\${(.+?)}$", re.S).match(x)
if m:
code = ast.PythonCode(
m.group(1).rstrip(), **self.exception_kwargs
)
# we aren't discarding "declared_identifiers" here,
# which we do so that list comprehension-declared
# variables aren't counted. As yet can't find a
# condition that requires it here.
undeclared_identifiers = undeclared_identifiers.union(
code.undeclared_identifiers
)
expr.append("(%s)" % m.group(1))
else:
if x:
expr.append(repr(x))
self.parsed_attributes[key] = " + ".join(expr) or repr("")
elif key in nonexpressions:
if re.search(r"\${.+?}", self.attributes[key]):
raise exceptions.CompileException(
"Attibute '%s' in tag '%s' does not allow embedded "
"expressions" % (key, self.keyword),
**self.exception_kwargs
)
self.parsed_attributes[key] = repr(self.attributes[key])
else:
raise exceptions.CompileException(
"Invalid attribute for tag '%s': '%s'"
% (self.keyword, key),
**self.exception_kwargs
)
self.expression_undeclared_identifiers = undeclared_identifiers
def declared_identifiers(self):
return []
def undeclared_identifiers(self):
return self.expression_undeclared_identifiers
def __repr__(self):
return "%s(%r, %s, %r, %r)" % (
self.__class__.__name__,
self.keyword,
util.sorted_dict_repr(self.attributes),
(self.lineno, self.pos),
self.nodes,
)
class IncludeTag(Tag):
__keyword__ = "include"
def __init__(self, keyword, attributes, **kwargs):
super(IncludeTag, self).__init__(
keyword,
attributes,
("file", "import", "args"),
(),
("file",),
**kwargs
)
self.page_args = ast.PythonCode(
"__DUMMY(%s)" % attributes.get("args", ""), **self.exception_kwargs
)
def declared_identifiers(self):
return []
def undeclared_identifiers(self):
identifiers = self.page_args.undeclared_identifiers.difference(
set(["__DUMMY"])
).difference(self.page_args.declared_identifiers)
return identifiers.union(
super(IncludeTag, self).undeclared_identifiers()
)
class NamespaceTag(Tag):
__keyword__ = "namespace"
def __init__(self, keyword, attributes, **kwargs):
super(NamespaceTag, self).__init__(
keyword,
attributes,
("file",),
("name", "inheritable", "import", "module"),
(),
**kwargs
)
self.name = attributes.get("name", "__anon_%s" % hex(abs(id(self))))
if "name" not in attributes and "import" not in attributes:
raise exceptions.CompileException(
"'name' and/or 'import' attributes are required "
"for <%namespace>",
**self.exception_kwargs
)
if "file" in attributes and "module" in attributes:
raise exceptions.CompileException(
"<%namespace> may only have one of 'file' or 'module'",
**self.exception_kwargs
)
def declared_identifiers(self):
return []
class TextTag(Tag):
__keyword__ = "text"
def __init__(self, keyword, attributes, **kwargs):
super(TextTag, self).__init__(
keyword, attributes, (), ("filter"), (), **kwargs
)
self.filter_args = ast.ArgumentList(
attributes.get("filter", ""), **self.exception_kwargs
)
def undeclared_identifiers(self):
return self.filter_args.undeclared_identifiers.difference(
filters.DEFAULT_ESCAPES.keys()
).union(self.expression_undeclared_identifiers)
class DefTag(Tag):
__keyword__ = "def"
def __init__(self, keyword, attributes, **kwargs):
expressions = ["buffered", "cached"] + [
c for c in attributes if c.startswith("cache_")
]
super(DefTag, self).__init__(
keyword,
attributes,
expressions,
("name", "filter", "decorator"),
("name",),
**kwargs
)
name = attributes["name"]
if re.match(r"^[\w_]+$", name):
raise exceptions.CompileException(
"Missing parenthesis in %def", **self.exception_kwargs
)
self.function_decl = ast.FunctionDecl(
"def " + name + ":pass", **self.exception_kwargs
)
self.name = self.function_decl.funcname
self.decorator = attributes.get("decorator", "")
self.filter_args = ast.ArgumentList(
attributes.get("filter", ""), **self.exception_kwargs
)
is_anonymous = False
is_block = False
@property
def funcname(self):
return self.function_decl.funcname
def get_argument_expressions(self, **kw):
return self.function_decl.get_argument_expressions(**kw)
def declared_identifiers(self):
return self.function_decl.allargnames
def undeclared_identifiers(self):
res = []
for c in self.function_decl.defaults:
res += list(
ast.PythonCode(
c, **self.exception_kwargs
).undeclared_identifiers
)
return (
set(res)
.union(
self.filter_args.undeclared_identifiers.difference(
filters.DEFAULT_ESCAPES.keys()
)
)
.union(self.expression_undeclared_identifiers)
.difference(self.function_decl.allargnames)
)
class BlockTag(Tag):
__keyword__ = "block"
def __init__(self, keyword, attributes, **kwargs):
expressions = ["buffered", "cached", "args"] + [
c for c in attributes if c.startswith("cache_")
]
super(BlockTag, self).__init__(
keyword,
attributes,
expressions,
("name", "filter", "decorator"),
(),
**kwargs
)
name = attributes.get("name")
if name and not re.match(r"^[\w_]+$", name):
raise exceptions.CompileException(
"%block may not specify an argument signature",
**self.exception_kwargs
)
if not name and attributes.get("args", None):
raise exceptions.CompileException(
"Only named %blocks may specify args", **self.exception_kwargs
)
self.body_decl = ast.FunctionArgs(
attributes.get("args", ""), **self.exception_kwargs
)
self.name = name
self.decorator = attributes.get("decorator", "")
self.filter_args = ast.ArgumentList(
attributes.get("filter", ""), **self.exception_kwargs
)
is_block = True
@property
def is_anonymous(self):
return self.name is None
@property
def funcname(self):
return self.name or "__M_anon_%d" % (self.lineno,)
def get_argument_expressions(self, **kw):
return self.body_decl.get_argument_expressions(**kw)
def declared_identifiers(self):
return self.body_decl.allargnames
def undeclared_identifiers(self):
return (
self.filter_args.undeclared_identifiers.difference(
filters.DEFAULT_ESCAPES.keys()
)
).union(self.expression_undeclared_identifiers)
class CallTag(Tag):
__keyword__ = "call"
def __init__(self, keyword, attributes, **kwargs):
super(CallTag, self).__init__(
keyword, attributes, ("args"), ("expr",), ("expr",), **kwargs
)
self.expression = attributes["expr"]
self.code = ast.PythonCode(self.expression, **self.exception_kwargs)
self.body_decl = ast.FunctionArgs(
attributes.get("args", ""), **self.exception_kwargs
)
def declared_identifiers(self):
return self.code.declared_identifiers.union(self.body_decl.allargnames)
def undeclared_identifiers(self):
return self.code.undeclared_identifiers.difference(
self.code.declared_identifiers
)
class CallNamespaceTag(Tag):
def __init__(self, namespace, defname, attributes, **kwargs):
super(CallNamespaceTag, self).__init__(
namespace + ":" + defname,
attributes,
tuple(attributes.keys()) + ("args",),
(),
(),
**kwargs
)
self.expression = "%s.%s(%s)" % (
namespace,
defname,
",".join(
[
"%s=%s" % (k, v)
for k, v in self.parsed_attributes.items()
if k != "args"
]
),
)
self.code = ast.PythonCode(self.expression, **self.exception_kwargs)
self.body_decl = ast.FunctionArgs(
attributes.get("args", ""), **self.exception_kwargs
)
def declared_identifiers(self):
return self.code.declared_identifiers.union(self.body_decl.allargnames)
def undeclared_identifiers(self):
return self.code.undeclared_identifiers.difference(
self.code.declared_identifiers
)
class InheritTag(Tag):
__keyword__ = "inherit"
def __init__(self, keyword, attributes, **kwargs):
super(InheritTag, self).__init__(
keyword, attributes, ("file",), (), ("file",), **kwargs
)
class PageTag(Tag):
__keyword__ = "page"
def __init__(self, keyword, attributes, **kwargs):
expressions = [
"cached",
"args",
"expression_filter",
"enable_loop",
] + [c for c in attributes if c.startswith("cache_")]
super(PageTag, self).__init__(
keyword, attributes, expressions, (), (), **kwargs
)
self.body_decl = ast.FunctionArgs(
attributes.get("args", ""), **self.exception_kwargs
)
self.filter_args = ast.ArgumentList(
attributes.get("expression_filter", ""), **self.exception_kwargs
)
def declared_identifiers(self):
return self.body_decl.allargnames