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Posted to commits@ambari.apache.org by nc...@apache.org on 2014/09/05 00:35:56 UTC
[17/59] [abbrv] Revert "AMBARI-7138. Ambari RPM deals with jinja2
dependency incorrectly (aonishuk)"
http://git-wip-us.apache.org/repos/asf/ambari/blob/570de228/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/nodes.py
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diff --git a/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/nodes.py b/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/nodes.py
deleted file mode 100644
index 804070c..0000000
--- a/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/nodes.py
+++ /dev/null
@@ -1,901 +0,0 @@
-# -*- coding: utf-8 -*-
-"""
- ambari_jinja2.nodes
- ~~~~~~~~~~~~
-
- This module implements additional nodes derived from the ast base node.
-
- It also provides some node tree helper functions like `in_lineno` and
- `get_nodes` used by the parser and translator in order to normalize
- python and jinja nodes.
-
- :copyright: (c) 2010 by the Jinja Team.
- :license: BSD, see LICENSE for more details.
-"""
-import operator
-from itertools import chain, izip
-from collections import deque
-from ambari_jinja2.utils import Markup, MethodType, FunctionType
-
-
-#: the types we support for context functions
-_context_function_types = (FunctionType, MethodType)
-
-
-_binop_to_func = {
- '*': operator.mul,
- '/': operator.truediv,
- '//': operator.floordiv,
- '**': operator.pow,
- '%': operator.mod,
- '+': operator.add,
- '-': operator.sub
-}
-
-_uaop_to_func = {
- 'not': operator.not_,
- '+': operator.pos,
- '-': operator.neg
-}
-
-_cmpop_to_func = {
- 'eq': operator.eq,
- 'ne': operator.ne,
- 'gt': operator.gt,
- 'gteq': operator.ge,
- 'lt': operator.lt,
- 'lteq': operator.le,
- 'in': lambda a, b: a in b,
- 'notin': lambda a, b: a not in b
-}
-
-
-class Impossible(Exception):
- """Raised if the node could not perform a requested action."""
-
-
-class NodeType(type):
- """A metaclass for nodes that handles the field and attribute
- inheritance. fields and attributes from the parent class are
- automatically forwarded to the child."""
-
- def __new__(cls, name, bases, d):
- for attr in 'fields', 'attributes':
- storage = []
- storage.extend(getattr(bases[0], attr, ()))
- storage.extend(d.get(attr, ()))
- assert len(bases) == 1, 'multiple inheritance not allowed'
- assert len(storage) == len(set(storage)), 'layout conflict'
- d[attr] = tuple(storage)
- d.setdefault('abstract', False)
- return type.__new__(cls, name, bases, d)
-
-
-class EvalContext(object):
- """Holds evaluation time information. Custom attributes can be attached
- to it in extensions.
- """
-
- def __init__(self, environment, template_name=None):
- if callable(environment.autoescape):
- self.autoescape = environment.autoescape(template_name)
- else:
- self.autoescape = environment.autoescape
- self.volatile = False
-
- def save(self):
- return self.__dict__.copy()
-
- def revert(self, old):
- self.__dict__.clear()
- self.__dict__.update(old)
-
-
-def get_eval_context(node, ctx):
- if ctx is None:
- if node.environment is None:
- raise RuntimeError('if no eval context is passed, the '
- 'node must have an attached '
- 'environment.')
- return EvalContext(node.environment)
- return ctx
-
-
-class Node(object):
- """Baseclass for all Jinja2 nodes. There are a number of nodes available
- of different types. There are three major types:
-
- - :class:`Stmt`: statements
- - :class:`Expr`: expressions
- - :class:`Helper`: helper nodes
- - :class:`Template`: the outermost wrapper node
-
- All nodes have fields and attributes. Fields may be other nodes, lists,
- or arbitrary values. Fields are passed to the constructor as regular
- positional arguments, attributes as keyword arguments. Each node has
- two attributes: `lineno` (the line number of the node) and `environment`.
- The `environment` attribute is set at the end of the parsing process for
- all nodes automatically.
- """
- __metaclass__ = NodeType
- fields = ()
- attributes = ('lineno', 'environment')
- abstract = True
-
- def __init__(self, *fields, **attributes):
- if self.abstract:
- raise TypeError('abstract nodes are not instanciable')
- if fields:
- if len(fields) != len(self.fields):
- if not self.fields:
- raise TypeError('%r takes 0 arguments' %
- self.__class__.__name__)
- raise TypeError('%r takes 0 or %d argument%s' % (
- self.__class__.__name__,
- len(self.fields),
- len(self.fields) != 1 and 's' or ''
- ))
- for name, arg in izip(self.fields, fields):
- setattr(self, name, arg)
- for attr in self.attributes:
- setattr(self, attr, attributes.pop(attr, None))
- if attributes:
- raise TypeError('unknown attribute %r' %
- iter(attributes).next())
-
- def iter_fields(self, exclude=None, only=None):
- """This method iterates over all fields that are defined and yields
- ``(key, value)`` tuples. Per default all fields are returned, but
- it's possible to limit that to some fields by providing the `only`
- parameter or to exclude some using the `exclude` parameter. Both
- should be sets or tuples of field names.
- """
- for name in self.fields:
- if (exclude is only is None) or \
- (exclude is not None and name not in exclude) or \
- (only is not None and name in only):
- try:
- yield name, getattr(self, name)
- except AttributeError:
- pass
-
- def iter_child_nodes(self, exclude=None, only=None):
- """Iterates over all direct child nodes of the node. This iterates
- over all fields and yields the values of they are nodes. If the value
- of a field is a list all the nodes in that list are returned.
- """
- for field, item in self.iter_fields(exclude, only):
- if isinstance(item, list):
- for n in item:
- if isinstance(n, Node):
- yield n
- elif isinstance(item, Node):
- yield item
-
- def find(self, node_type):
- """Find the first node of a given type. If no such node exists the
- return value is `None`.
- """
- for result in self.find_all(node_type):
- return result
-
- def find_all(self, node_type):
- """Find all the nodes of a given type. If the type is a tuple,
- the check is performed for any of the tuple items.
- """
- for child in self.iter_child_nodes():
- if isinstance(child, node_type):
- yield child
- for result in child.find_all(node_type):
- yield result
-
- def set_ctx(self, ctx):
- """Reset the context of a node and all child nodes. Per default the
- parser will all generate nodes that have a 'load' context as it's the
- most common one. This method is used in the parser to set assignment
- targets and other nodes to a store context.
- """
- todo = deque([self])
- while todo:
- node = todo.popleft()
- if 'ctx' in node.fields:
- node.ctx = ctx
- todo.extend(node.iter_child_nodes())
- return self
-
- def set_lineno(self, lineno, override=False):
- """Set the line numbers of the node and children."""
- todo = deque([self])
- while todo:
- node = todo.popleft()
- if 'lineno' in node.attributes:
- if node.lineno is None or override:
- node.lineno = lineno
- todo.extend(node.iter_child_nodes())
- return self
-
- def set_environment(self, environment):
- """Set the environment for all nodes."""
- todo = deque([self])
- while todo:
- node = todo.popleft()
- node.environment = environment
- todo.extend(node.iter_child_nodes())
- return self
-
- def __eq__(self, other):
- return type(self) is type(other) and \
- tuple(self.iter_fields()) == tuple(other.iter_fields())
-
- def __ne__(self, other):
- return not self.__eq__(other)
-
- def __repr__(self):
- return '%s(%s)' % (
- self.__class__.__name__,
- ', '.join('%s=%r' % (arg, getattr(self, arg, None)) for
- arg in self.fields)
- )
-
-
-class Stmt(Node):
- """Base node for all statements."""
- abstract = True
-
-
-class Helper(Node):
- """Nodes that exist in a specific context only."""
- abstract = True
-
-
-class Template(Node):
- """Node that represents a template. This must be the outermost node that
- is passed to the compiler.
- """
- fields = ('body',)
-
-
-class Output(Stmt):
- """A node that holds multiple expressions which are then printed out.
- This is used both for the `print` statement and the regular template data.
- """
- fields = ('nodes',)
-
-
-class Extends(Stmt):
- """Represents an extends statement."""
- fields = ('template',)
-
-
-class For(Stmt):
- """The for loop. `target` is the target for the iteration (usually a
- :class:`Name` or :class:`Tuple`), `iter` the iterable. `body` is a list
- of nodes that are used as loop-body, and `else_` a list of nodes for the
- `else` block. If no else node exists it has to be an empty list.
-
- For filtered nodes an expression can be stored as `test`, otherwise `None`.
- """
- fields = ('target', 'iter', 'body', 'else_', 'test', 'recursive')
-
-
-class If(Stmt):
- """If `test` is true, `body` is rendered, else `else_`."""
- fields = ('test', 'body', 'else_')
-
-
-class Macro(Stmt):
- """A macro definition. `name` is the name of the macro, `args` a list of
- arguments and `defaults` a list of defaults if there are any. `body` is
- a list of nodes for the macro body.
- """
- fields = ('name', 'args', 'defaults', 'body')
-
-
-class CallBlock(Stmt):
- """Like a macro without a name but a call instead. `call` is called with
- the unnamed macro as `caller` argument this node holds.
- """
- fields = ('call', 'args', 'defaults', 'body')
-
-
-class FilterBlock(Stmt):
- """Node for filter sections."""
- fields = ('body', 'filter')
-
-
-class Block(Stmt):
- """A node that represents a block."""
- fields = ('name', 'body', 'scoped')
-
-
-class Include(Stmt):
- """A node that represents the include tag."""
- fields = ('template', 'with_context', 'ignore_missing')
-
-
-class Import(Stmt):
- """A node that represents the import tag."""
- fields = ('template', 'target', 'with_context')
-
-
-class FromImport(Stmt):
- """A node that represents the from import tag. It's important to not
- pass unsafe names to the name attribute. The compiler translates the
- attribute lookups directly into getattr calls and does *not* use the
- subscript callback of the interface. As exported variables may not
- start with double underscores (which the parser asserts) this is not a
- problem for regular Jinja code, but if this node is used in an extension
- extra care must be taken.
-
- The list of names may contain tuples if aliases are wanted.
- """
- fields = ('template', 'names', 'with_context')
-
-
-class ExprStmt(Stmt):
- """A statement that evaluates an expression and discards the result."""
- fields = ('node',)
-
-
-class Assign(Stmt):
- """Assigns an expression to a target."""
- fields = ('target', 'node')
-
-
-class Expr(Node):
- """Baseclass for all expressions."""
- abstract = True
-
- def as_const(self, eval_ctx=None):
- """Return the value of the expression as constant or raise
- :exc:`Impossible` if this was not possible.
-
- An :class:`EvalContext` can be provided, if none is given
- a default context is created which requires the nodes to have
- an attached environment.
-
- .. versionchanged:: 2.4
- the `eval_ctx` parameter was added.
- """
- raise Impossible()
-
- def can_assign(self):
- """Check if it's possible to assign something to this node."""
- return False
-
-
-class BinExpr(Expr):
- """Baseclass for all binary expressions."""
- fields = ('left', 'right')
- operator = None
- abstract = True
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- f = _binop_to_func[self.operator]
- try:
- return f(self.left.as_const(eval_ctx), self.right.as_const(eval_ctx))
- except:
- raise Impossible()
-
-
-class UnaryExpr(Expr):
- """Baseclass for all unary expressions."""
- fields = ('node',)
- operator = None
- abstract = True
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- f = _uaop_to_func[self.operator]
- try:
- return f(self.node.as_const(eval_ctx))
- except:
- raise Impossible()
-
-
-class Name(Expr):
- """Looks up a name or stores a value in a name.
- The `ctx` of the node can be one of the following values:
-
- - `store`: store a value in the name
- - `load`: load that name
- - `param`: like `store` but if the name was defined as function parameter.
- """
- fields = ('name', 'ctx')
-
- def can_assign(self):
- return self.name not in ('true', 'false', 'none',
- 'True', 'False', 'None')
-
-
-class Literal(Expr):
- """Baseclass for literals."""
- abstract = True
-
-
-class Const(Literal):
- """All constant values. The parser will return this node for simple
- constants such as ``42`` or ``"foo"`` but it can be used to store more
- complex values such as lists too. Only constants with a safe
- representation (objects where ``eval(repr(x)) == x`` is true).
- """
- fields = ('value',)
-
- def as_const(self, eval_ctx=None):
- return self.value
-
- @classmethod
- def from_untrusted(cls, value, lineno=None, environment=None):
- """Return a const object if the value is representable as
- constant value in the generated code, otherwise it will raise
- an `Impossible` exception.
- """
- from compiler import has_safe_repr
- if not has_safe_repr(value):
- raise Impossible()
- return cls(value, lineno=lineno, environment=environment)
-
-
-class TemplateData(Literal):
- """A constant template string."""
- fields = ('data',)
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- if eval_ctx.volatile:
- raise Impossible()
- if eval_ctx.autoescape:
- return Markup(self.data)
- return self.data
-
-
-class Tuple(Literal):
- """For loop unpacking and some other things like multiple arguments
- for subscripts. Like for :class:`Name` `ctx` specifies if the tuple
- is used for loading the names or storing.
- """
- fields = ('items', 'ctx')
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- return tuple(x.as_const(eval_ctx) for x in self.items)
-
- def can_assign(self):
- for item in self.items:
- if not item.can_assign():
- return False
- return True
-
-
-class List(Literal):
- """Any list literal such as ``[1, 2, 3]``"""
- fields = ('items',)
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- return [x.as_const(eval_ctx) for x in self.items]
-
-
-class Dict(Literal):
- """Any dict literal such as ``{1: 2, 3: 4}``. The items must be a list of
- :class:`Pair` nodes.
- """
- fields = ('items',)
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- return dict(x.as_const(eval_ctx) for x in self.items)
-
-
-class Pair(Helper):
- """A key, value pair for dicts."""
- fields = ('key', 'value')
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- return self.key.as_const(eval_ctx), self.value.as_const(eval_ctx)
-
-
-class Keyword(Helper):
- """A key, value pair for keyword arguments where key is a string."""
- fields = ('key', 'value')
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- return self.key, self.value.as_const(eval_ctx)
-
-
-class CondExpr(Expr):
- """A conditional expression (inline if expression). (``{{
- foo if bar else baz }}``)
- """
- fields = ('test', 'expr1', 'expr2')
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- if self.test.as_const(eval_ctx):
- return self.expr1.as_const(eval_ctx)
-
- # if we evaluate to an undefined object, we better do that at runtime
- if self.expr2 is None:
- raise Impossible()
-
- return self.expr2.as_const(eval_ctx)
-
-
-class Filter(Expr):
- """This node applies a filter on an expression. `name` is the name of
- the filter, the rest of the fields are the same as for :class:`Call`.
-
- If the `node` of a filter is `None` the contents of the last buffer are
- filtered. Buffers are created by macros and filter blocks.
- """
- fields = ('node', 'name', 'args', 'kwargs', 'dyn_args', 'dyn_kwargs')
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- if eval_ctx.volatile or self.node is None:
- raise Impossible()
- # we have to be careful here because we call filter_ below.
- # if this variable would be called filter, 2to3 would wrap the
- # call in a list beause it is assuming we are talking about the
- # builtin filter function here which no longer returns a list in
- # python 3. because of that, do not rename filter_ to filter!
- filter_ = self.environment.filters.get(self.name)
- if filter_ is None or getattr(filter_, 'contextfilter', False):
- raise Impossible()
- obj = self.node.as_const(eval_ctx)
- args = [x.as_const(eval_ctx) for x in self.args]
- if getattr(filter_, 'evalcontextfilter', False):
- args.insert(0, eval_ctx)
- elif getattr(filter_, 'environmentfilter', False):
- args.insert(0, self.environment)
- kwargs = dict(x.as_const(eval_ctx) for x in self.kwargs)
- if self.dyn_args is not None:
- try:
- args.extend(self.dyn_args.as_const(eval_ctx))
- except:
- raise Impossible()
- if self.dyn_kwargs is not None:
- try:
- kwargs.update(self.dyn_kwargs.as_const(eval_ctx))
- except:
- raise Impossible()
- try:
- return filter_(obj, *args, **kwargs)
- except:
- raise Impossible()
-
-
-class Test(Expr):
- """Applies a test on an expression. `name` is the name of the test, the
- rest of the fields are the same as for :class:`Call`.
- """
- fields = ('node', 'name', 'args', 'kwargs', 'dyn_args', 'dyn_kwargs')
-
-
-class Call(Expr):
- """Calls an expression. `args` is a list of arguments, `kwargs` a list
- of keyword arguments (list of :class:`Keyword` nodes), and `dyn_args`
- and `dyn_kwargs` has to be either `None` or a node that is used as
- node for dynamic positional (``*args``) or keyword (``**kwargs``)
- arguments.
- """
- fields = ('node', 'args', 'kwargs', 'dyn_args', 'dyn_kwargs')
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- if eval_ctx.volatile:
- raise Impossible()
- obj = self.node.as_const(eval_ctx)
-
- # don't evaluate context functions
- args = [x.as_const(eval_ctx) for x in self.args]
- if isinstance(obj, _context_function_types):
- if getattr(obj, 'contextfunction', False):
- raise Impossible()
- elif getattr(obj, 'evalcontextfunction', False):
- args.insert(0, eval_ctx)
- elif getattr(obj, 'environmentfunction', False):
- args.insert(0, self.environment)
-
- kwargs = dict(x.as_const(eval_ctx) for x in self.kwargs)
- if self.dyn_args is not None:
- try:
- args.extend(self.dyn_args.as_const(eval_ctx))
- except:
- raise Impossible()
- if self.dyn_kwargs is not None:
- try:
- kwargs.update(self.dyn_kwargs.as_const(eval_ctx))
- except:
- raise Impossible()
- try:
- return obj(*args, **kwargs)
- except:
- raise Impossible()
-
-
-class Getitem(Expr):
- """Get an attribute or item from an expression and prefer the item."""
- fields = ('node', 'arg', 'ctx')
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- if self.ctx != 'load':
- raise Impossible()
- try:
- return self.environment.getitem(self.node.as_const(eval_ctx),
- self.arg.as_const(eval_ctx))
- except:
- raise Impossible()
-
- def can_assign(self):
- return False
-
-
-class Getattr(Expr):
- """Get an attribute or item from an expression that is a ascii-only
- bytestring and prefer the attribute.
- """
- fields = ('node', 'attr', 'ctx')
-
- def as_const(self, eval_ctx=None):
- if self.ctx != 'load':
- raise Impossible()
- try:
- eval_ctx = get_eval_context(self, eval_ctx)
- return self.environment.getattr(self.node.as_const(eval_ctx),
- self.attr)
- except:
- raise Impossible()
-
- def can_assign(self):
- return False
-
-
-class Slice(Expr):
- """Represents a slice object. This must only be used as argument for
- :class:`Subscript`.
- """
- fields = ('start', 'stop', 'step')
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- def const(obj):
- if obj is None:
- return None
- return obj.as_const(eval_ctx)
- return slice(const(self.start), const(self.stop), const(self.step))
-
-
-class Concat(Expr):
- """Concatenates the list of expressions provided after converting them to
- unicode.
- """
- fields = ('nodes',)
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- return ''.join(unicode(x.as_const(eval_ctx)) for x in self.nodes)
-
-
-class Compare(Expr):
- """Compares an expression with some other expressions. `ops` must be a
- list of :class:`Operand`\s.
- """
- fields = ('expr', 'ops')
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- result = value = self.expr.as_const(eval_ctx)
- try:
- for op in self.ops:
- new_value = op.expr.as_const(eval_ctx)
- result = _cmpop_to_func[op.op](value, new_value)
- value = new_value
- except:
- raise Impossible()
- return result
-
-
-class Operand(Helper):
- """Holds an operator and an expression."""
- fields = ('op', 'expr')
-
-if __debug__:
- Operand.__doc__ += '\nThe following operators are available: ' + \
- ', '.join(sorted('``%s``' % x for x in set(_binop_to_func) |
- set(_uaop_to_func) | set(_cmpop_to_func)))
-
-
-class Mul(BinExpr):
- """Multiplies the left with the right node."""
- operator = '*'
-
-
-class Div(BinExpr):
- """Divides the left by the right node."""
- operator = '/'
-
-
-class FloorDiv(BinExpr):
- """Divides the left by the right node and truncates conver the
- result into an integer by truncating.
- """
- operator = '//'
-
-
-class Add(BinExpr):
- """Add the left to the right node."""
- operator = '+'
-
-
-class Sub(BinExpr):
- """Substract the right from the left node."""
- operator = '-'
-
-
-class Mod(BinExpr):
- """Left modulo right."""
- operator = '%'
-
-
-class Pow(BinExpr):
- """Left to the power of right."""
- operator = '**'
-
-
-class And(BinExpr):
- """Short circuited AND."""
- operator = 'and'
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- return self.left.as_const(eval_ctx) and self.right.as_const(eval_ctx)
-
-
-class Or(BinExpr):
- """Short circuited OR."""
- operator = 'or'
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- return self.left.as_const(eval_ctx) or self.right.as_const(eval_ctx)
-
-
-class Not(UnaryExpr):
- """Negate the expression."""
- operator = 'not'
-
-
-class Neg(UnaryExpr):
- """Make the expression negative."""
- operator = '-'
-
-
-class Pos(UnaryExpr):
- """Make the expression positive (noop for most expressions)"""
- operator = '+'
-
-
-# Helpers for extensions
-
-
-class EnvironmentAttribute(Expr):
- """Loads an attribute from the environment object. This is useful for
- extensions that want to call a callback stored on the environment.
- """
- fields = ('name',)
-
-
-class ExtensionAttribute(Expr):
- """Returns the attribute of an extension bound to the environment.
- The identifier is the identifier of the :class:`Extension`.
-
- This node is usually constructed by calling the
- :meth:`~ambari_jinja2.ext.Extension.attr` method on an extension.
- """
- fields = ('identifier', 'name')
-
-
-class ImportedName(Expr):
- """If created with an import name the import name is returned on node
- access. For example ``ImportedName('cgi.escape')`` returns the `escape`
- function from the cgi module on evaluation. Imports are optimized by the
- compiler so there is no need to assign them to local variables.
- """
- fields = ('importname',)
-
-
-class InternalName(Expr):
- """An internal name in the compiler. You cannot create these nodes
- yourself but the parser provides a
- :meth:`~ambari_jinja2.parser.Parser.free_identifier` method that creates
- a new identifier for you. This identifier is not available from the
- template and is not threated specially by the compiler.
- """
- fields = ('name',)
-
- def __init__(self):
- raise TypeError('Can\'t create internal names. Use the '
- '`free_identifier` method on a parser.')
-
-
-class MarkSafe(Expr):
- """Mark the wrapped expression as safe (wrap it as `Markup`)."""
- fields = ('expr',)
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- return Markup(self.expr.as_const(eval_ctx))
-
-
-class MarkSafeIfAutoescape(Expr):
- """Mark the wrapped expression as safe (wrap it as `Markup`) but
- only if autoescaping is active.
-
- .. versionadded:: 2.5
- """
- fields = ('expr',)
-
- def as_const(self, eval_ctx=None):
- eval_ctx = get_eval_context(self, eval_ctx)
- if eval_ctx.volatile:
- raise Impossible()
- expr = self.expr.as_const(eval_ctx)
- if eval_ctx.autoescape:
- return Markup(expr)
- return expr
-
-
-class ContextReference(Expr):
- """Returns the current template context. It can be used like a
- :class:`Name` node, with a ``'load'`` ctx and will return the
- current :class:`~ambari_jinja2.runtime.Context` object.
-
- Here an example that assigns the current template name to a
- variable named `foo`::
-
- Assign(Name('foo', ctx='store'),
- Getattr(ContextReference(), 'name'))
- """
-
-
-class Continue(Stmt):
- """Continue a loop."""
-
-
-class Break(Stmt):
- """Break a loop."""
-
-
-class Scope(Stmt):
- """An artificial scope."""
- fields = ('body',)
-
-
-class EvalContextModifier(Stmt):
- """Modifies the eval context. For each option that should be modified,
- a :class:`Keyword` has to be added to the :attr:`options` list.
-
- Example to change the `autoescape` setting::
-
- EvalContextModifier(options=[Keyword('autoescape', Const(True))])
- """
- fields = ('options',)
-
-
-class ScopedEvalContextModifier(EvalContextModifier):
- """Modifies the eval context and reverts it later. Works exactly like
- :class:`EvalContextModifier` but will only modify the
- :class:`~ambari_jinja2.nodes.EvalContext` for nodes in the :attr:`body`.
- """
- fields = ('body',)
-
-
-# make sure nobody creates custom nodes
-def _failing_new(*args, **kwargs):
- raise TypeError('can\'t create custom node types')
-NodeType.__new__ = staticmethod(_failing_new); del _failing_new
http://git-wip-us.apache.org/repos/asf/ambari/blob/570de228/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/optimizer.py
----------------------------------------------------------------------
diff --git a/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/optimizer.py b/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/optimizer.py
deleted file mode 100644
index b014396..0000000
--- a/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/optimizer.py
+++ /dev/null
@@ -1,68 +0,0 @@
-# -*- coding: utf-8 -*-
-"""
- ambari_jinja2.optimizer
- ~~~~~~~~~~~~~~~~
-
- The jinja optimizer is currently trying to constant fold a few expressions
- and modify the AST in place so that it should be easier to evaluate it.
-
- Because the AST does not contain all the scoping information and the
- compiler has to find that out, we cannot do all the optimizations we
- want. For example loop unrolling doesn't work because unrolled loops would
- have a different scoping.
-
- The solution would be a second syntax tree that has the scoping rules stored.
-
- :copyright: (c) 2010 by the Jinja Team.
- :license: BSD.
-"""
-from ambari_jinja2 import nodes
-from ambari_jinja2.visitor import NodeTransformer
-
-
-def optimize(node, environment):
- """The context hint can be used to perform an static optimization
- based on the context given."""
- optimizer = Optimizer(environment)
- return optimizer.visit(node)
-
-
-class Optimizer(NodeTransformer):
-
- def __init__(self, environment):
- self.environment = environment
-
- def visit_If(self, node):
- """Eliminate dead code."""
- # do not optimize ifs that have a block inside so that it doesn't
- # break super().
- if node.find(nodes.Block) is not None:
- return self.generic_visit(node)
- try:
- val = self.visit(node.test).as_const()
- except nodes.Impossible:
- return self.generic_visit(node)
- if val:
- body = node.body
- else:
- body = node.else_
- result = []
- for node in body:
- result.extend(self.visit_list(node))
- return result
-
- def fold(self, node):
- """Do constant folding."""
- node = self.generic_visit(node)
- try:
- return nodes.Const.from_untrusted(node.as_const(),
- lineno=node.lineno,
- environment=self.environment)
- except nodes.Impossible:
- return node
-
- visit_Add = visit_Sub = visit_Mul = visit_Div = visit_FloorDiv = \
- visit_Pow = visit_Mod = visit_And = visit_Or = visit_Pos = visit_Neg = \
- visit_Not = visit_Compare = visit_Getitem = visit_Getattr = visit_Call = \
- visit_Filter = visit_Test = visit_CondExpr = fold
- del fold
http://git-wip-us.apache.org/repos/asf/ambari/blob/570de228/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/parser.py
----------------------------------------------------------------------
diff --git a/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/parser.py b/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/parser.py
deleted file mode 100644
index a14c055..0000000
--- a/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/parser.py
+++ /dev/null
@@ -1,896 +0,0 @@
-# -*- coding: utf-8 -*-
-"""
- ambari_jinja2.parser
- ~~~~~~~~~~~~~
-
- Implements the template parser.
-
- :copyright: (c) 2010 by the Jinja Team.
- :license: BSD, see LICENSE for more details.
-"""
-from ambari_jinja2 import nodes
-from ambari_jinja2.exceptions import TemplateSyntaxError, TemplateAssertionError
-from ambari_jinja2.utils import next
-from ambari_jinja2.lexer import describe_token, describe_token_expr
-
-
-#: statements that callinto
-_statement_keywords = frozenset(['for', 'if', 'block', 'extends', 'print',
- 'macro', 'include', 'from', 'import',
- 'set'])
-_compare_operators = frozenset(['eq', 'ne', 'lt', 'lteq', 'gt', 'gteq'])
-
-
-class Parser(object):
- """This is the central parsing class Jinja2 uses. It's passed to
- extensions and can be used to parse expressions or statements.
- """
-
- def __init__(self, environment, source, name=None, filename=None,
- state=None):
- self.environment = environment
- self.stream = environment._tokenize(source, name, filename, state)
- self.name = name
- self.filename = filename
- self.closed = False
- self.extensions = {}
- for extension in environment.iter_extensions():
- for tag in extension.tags:
- self.extensions[tag] = extension.parse
- self._last_identifier = 0
- self._tag_stack = []
- self._end_token_stack = []
-
- def fail(self, msg, lineno=None, exc=TemplateSyntaxError):
- """Convenience method that raises `exc` with the message, passed
- line number or last line number as well as the current name and
- filename.
- """
- if lineno is None:
- lineno = self.stream.current.lineno
- raise exc(msg, lineno, self.name, self.filename)
-
- def _fail_ut_eof(self, name, end_token_stack, lineno):
- expected = []
- for exprs in end_token_stack:
- expected.extend(map(describe_token_expr, exprs))
- if end_token_stack:
- currently_looking = ' or '.join(
- "'%s'" % describe_token_expr(expr)
- for expr in end_token_stack[-1])
- else:
- currently_looking = None
-
- if name is None:
- message = ['Unexpected end of template.']
- else:
- message = ['Encountered unknown tag \'%s\'.' % name]
-
- if currently_looking:
- if name is not None and name in expected:
- message.append('You probably made a nesting mistake. Jinja '
- 'is expecting this tag, but currently looking '
- 'for %s.' % currently_looking)
- else:
- message.append('Jinja was looking for the following tags: '
- '%s.' % currently_looking)
-
- if self._tag_stack:
- message.append('The innermost block that needs to be '
- 'closed is \'%s\'.' % self._tag_stack[-1])
-
- self.fail(' '.join(message), lineno)
-
- def fail_unknown_tag(self, name, lineno=None):
- """Called if the parser encounters an unknown tag. Tries to fail
- with a human readable error message that could help to identify
- the problem.
- """
- return self._fail_ut_eof(name, self._end_token_stack, lineno)
-
- def fail_eof(self, end_tokens=None, lineno=None):
- """Like fail_unknown_tag but for end of template situations."""
- stack = list(self._end_token_stack)
- if end_tokens is not None:
- stack.append(end_tokens)
- return self._fail_ut_eof(None, stack, lineno)
-
- def is_tuple_end(self, extra_end_rules=None):
- """Are we at the end of a tuple?"""
- if self.stream.current.type in ('variable_end', 'block_end', 'rparen'):
- return True
- elif extra_end_rules is not None:
- return self.stream.current.test_any(extra_end_rules)
- return False
-
- def free_identifier(self, lineno=None):
- """Return a new free identifier as :class:`~ambari_jinja2.nodes.InternalName`."""
- self._last_identifier += 1
- rv = object.__new__(nodes.InternalName)
- nodes.Node.__init__(rv, 'fi%d' % self._last_identifier, lineno=lineno)
- return rv
-
- def parse_statement(self):
- """Parse a single statement."""
- token = self.stream.current
- if token.type != 'name':
- self.fail('tag name expected', token.lineno)
- self._tag_stack.append(token.value)
- pop_tag = True
- try:
- if token.value in _statement_keywords:
- return getattr(self, 'parse_' + self.stream.current.value)()
- if token.value == 'call':
- return self.parse_call_block()
- if token.value == 'filter':
- return self.parse_filter_block()
- ext = self.extensions.get(token.value)
- if ext is not None:
- return ext(self)
-
- # did not work out, remove the token we pushed by accident
- # from the stack so that the unknown tag fail function can
- # produce a proper error message.
- self._tag_stack.pop()
- pop_tag = False
- self.fail_unknown_tag(token.value, token.lineno)
- finally:
- if pop_tag:
- self._tag_stack.pop()
-
- def parse_statements(self, end_tokens, drop_needle=False):
- """Parse multiple statements into a list until one of the end tokens
- is reached. This is used to parse the body of statements as it also
- parses template data if appropriate. The parser checks first if the
- current token is a colon and skips it if there is one. Then it checks
- for the block end and parses until if one of the `end_tokens` is
- reached. Per default the active token in the stream at the end of
- the call is the matched end token. If this is not wanted `drop_needle`
- can be set to `True` and the end token is removed.
- """
- # the first token may be a colon for python compatibility
- self.stream.skip_if('colon')
-
- # in the future it would be possible to add whole code sections
- # by adding some sort of end of statement token and parsing those here.
- self.stream.expect('block_end')
- result = self.subparse(end_tokens)
-
- # we reached the end of the template too early, the subparser
- # does not check for this, so we do that now
- if self.stream.current.type == 'eof':
- self.fail_eof(end_tokens)
-
- if drop_needle:
- next(self.stream)
- return result
-
- def parse_set(self):
- """Parse an assign statement."""
- lineno = next(self.stream).lineno
- target = self.parse_assign_target()
- self.stream.expect('assign')
- expr = self.parse_tuple()
- return nodes.Assign(target, expr, lineno=lineno)
-
- def parse_for(self):
- """Parse a for loop."""
- lineno = self.stream.expect('name:for').lineno
- target = self.parse_assign_target(extra_end_rules=('name:in',))
- self.stream.expect('name:in')
- iter = self.parse_tuple(with_condexpr=False,
- extra_end_rules=('name:recursive',))
- test = None
- if self.stream.skip_if('name:if'):
- test = self.parse_expression()
- recursive = self.stream.skip_if('name:recursive')
- body = self.parse_statements(('name:endfor', 'name:else'))
- if next(self.stream).value == 'endfor':
- else_ = []
- else:
- else_ = self.parse_statements(('name:endfor',), drop_needle=True)
- return nodes.For(target, iter, body, else_, test,
- recursive, lineno=lineno)
-
- def parse_if(self):
- """Parse an if construct."""
- node = result = nodes.If(lineno=self.stream.expect('name:if').lineno)
- while 1:
- node.test = self.parse_tuple(with_condexpr=False)
- node.body = self.parse_statements(('name:elif', 'name:else',
- 'name:endif'))
- token = next(self.stream)
- if token.test('name:elif'):
- new_node = nodes.If(lineno=self.stream.current.lineno)
- node.else_ = [new_node]
- node = new_node
- continue
- elif token.test('name:else'):
- node.else_ = self.parse_statements(('name:endif',),
- drop_needle=True)
- else:
- node.else_ = []
- break
- return result
-
- def parse_block(self):
- node = nodes.Block(lineno=next(self.stream).lineno)
- node.name = self.stream.expect('name').value
- node.scoped = self.stream.skip_if('name:scoped')
-
- # common problem people encounter when switching from django
- # to jinja. we do not support hyphens in block names, so let's
- # raise a nicer error message in that case.
- if self.stream.current.type == 'sub':
- self.fail('Block names in Jinja have to be valid Python '
- 'identifiers and may not contain hypens, use an '
- 'underscore instead.')
-
- node.body = self.parse_statements(('name:endblock',), drop_needle=True)
- self.stream.skip_if('name:' + node.name)
- return node
-
- def parse_extends(self):
- node = nodes.Extends(lineno=next(self.stream).lineno)
- node.template = self.parse_expression()
- return node
-
- def parse_import_context(self, node, default):
- if self.stream.current.test_any('name:with', 'name:without') and \
- self.stream.look().test('name:context'):
- node.with_context = next(self.stream).value == 'with'
- self.stream.skip()
- else:
- node.with_context = default
- return node
-
- def parse_include(self):
- node = nodes.Include(lineno=next(self.stream).lineno)
- node.template = self.parse_expression()
- if self.stream.current.test('name:ignore') and \
- self.stream.look().test('name:missing'):
- node.ignore_missing = True
- self.stream.skip(2)
- else:
- node.ignore_missing = False
- return self.parse_import_context(node, True)
-
- def parse_import(self):
- node = nodes.Import(lineno=next(self.stream).lineno)
- node.template = self.parse_expression()
- self.stream.expect('name:as')
- node.target = self.parse_assign_target(name_only=True).name
- return self.parse_import_context(node, False)
-
- def parse_from(self):
- node = nodes.FromImport(lineno=next(self.stream).lineno)
- node.template = self.parse_expression()
- self.stream.expect('name:import')
- node.names = []
-
- def parse_context():
- if self.stream.current.value in ('with', 'without') and \
- self.stream.look().test('name:context'):
- node.with_context = next(self.stream).value == 'with'
- self.stream.skip()
- return True
- return False
-
- while 1:
- if node.names:
- self.stream.expect('comma')
- if self.stream.current.type == 'name':
- if parse_context():
- break
- target = self.parse_assign_target(name_only=True)
- if target.name.startswith('_'):
- self.fail('names starting with an underline can not '
- 'be imported', target.lineno,
- exc=TemplateAssertionError)
- if self.stream.skip_if('name:as'):
- alias = self.parse_assign_target(name_only=True)
- node.names.append((target.name, alias.name))
- else:
- node.names.append(target.name)
- if parse_context() or self.stream.current.type != 'comma':
- break
- else:
- break
- if not hasattr(node, 'with_context'):
- node.with_context = False
- self.stream.skip_if('comma')
- return node
-
- def parse_signature(self, node):
- node.args = args = []
- node.defaults = defaults = []
- self.stream.expect('lparen')
- while self.stream.current.type != 'rparen':
- if args:
- self.stream.expect('comma')
- arg = self.parse_assign_target(name_only=True)
- arg.set_ctx('param')
- if self.stream.skip_if('assign'):
- defaults.append(self.parse_expression())
- args.append(arg)
- self.stream.expect('rparen')
-
- def parse_call_block(self):
- node = nodes.CallBlock(lineno=next(self.stream).lineno)
- if self.stream.current.type == 'lparen':
- self.parse_signature(node)
- else:
- node.args = []
- node.defaults = []
-
- node.call = self.parse_expression()
- if not isinstance(node.call, nodes.Call):
- self.fail('expected call', node.lineno)
- node.body = self.parse_statements(('name:endcall',), drop_needle=True)
- return node
-
- def parse_filter_block(self):
- node = nodes.FilterBlock(lineno=next(self.stream).lineno)
- node.filter = self.parse_filter(None, start_inline=True)
- node.body = self.parse_statements(('name:endfilter',),
- drop_needle=True)
- return node
-
- def parse_macro(self):
- node = nodes.Macro(lineno=next(self.stream).lineno)
- node.name = self.parse_assign_target(name_only=True).name
- self.parse_signature(node)
- node.body = self.parse_statements(('name:endmacro',),
- drop_needle=True)
- return node
-
- def parse_print(self):
- node = nodes.Output(lineno=next(self.stream).lineno)
- node.nodes = []
- while self.stream.current.type != 'block_end':
- if node.nodes:
- self.stream.expect('comma')
- node.nodes.append(self.parse_expression())
- return node
-
- def parse_assign_target(self, with_tuple=True, name_only=False,
- extra_end_rules=None):
- """Parse an assignment target. As Jinja2 allows assignments to
- tuples, this function can parse all allowed assignment targets. Per
- default assignments to tuples are parsed, that can be disable however
- by setting `with_tuple` to `False`. If only assignments to names are
- wanted `name_only` can be set to `True`. The `extra_end_rules`
- parameter is forwarded to the tuple parsing function.
- """
- if name_only:
- token = self.stream.expect('name')
- target = nodes.Name(token.value, 'store', lineno=token.lineno)
- else:
- if with_tuple:
- target = self.parse_tuple(simplified=True,
- extra_end_rules=extra_end_rules)
- else:
- target = self.parse_primary()
- target.set_ctx('store')
- if not target.can_assign():
- self.fail('can\'t assign to %r' % target.__class__.
- __name__.lower(), target.lineno)
- return target
-
- def parse_expression(self, with_condexpr=True):
- """Parse an expression. Per default all expressions are parsed, if
- the optional `with_condexpr` parameter is set to `False` conditional
- expressions are not parsed.
- """
- if with_condexpr:
- return self.parse_condexpr()
- return self.parse_or()
-
- def parse_condexpr(self):
- lineno = self.stream.current.lineno
- expr1 = self.parse_or()
- while self.stream.skip_if('name:if'):
- expr2 = self.parse_or()
- if self.stream.skip_if('name:else'):
- expr3 = self.parse_condexpr()
- else:
- expr3 = None
- expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno)
- lineno = self.stream.current.lineno
- return expr1
-
- def parse_or(self):
- lineno = self.stream.current.lineno
- left = self.parse_and()
- while self.stream.skip_if('name:or'):
- right = self.parse_and()
- left = nodes.Or(left, right, lineno=lineno)
- lineno = self.stream.current.lineno
- return left
-
- def parse_and(self):
- lineno = self.stream.current.lineno
- left = self.parse_not()
- while self.stream.skip_if('name:and'):
- right = self.parse_not()
- left = nodes.And(left, right, lineno=lineno)
- lineno = self.stream.current.lineno
- return left
-
- def parse_not(self):
- if self.stream.current.test('name:not'):
- lineno = next(self.stream).lineno
- return nodes.Not(self.parse_not(), lineno=lineno)
- return self.parse_compare()
-
- def parse_compare(self):
- lineno = self.stream.current.lineno
- expr = self.parse_add()
- ops = []
- while 1:
- token_type = self.stream.current.type
- if token_type in _compare_operators:
- next(self.stream)
- ops.append(nodes.Operand(token_type, self.parse_add()))
- elif self.stream.skip_if('name:in'):
- ops.append(nodes.Operand('in', self.parse_add()))
- elif self.stream.current.test('name:not') and \
- self.stream.look().test('name:in'):
- self.stream.skip(2)
- ops.append(nodes.Operand('notin', self.parse_add()))
- else:
- break
- lineno = self.stream.current.lineno
- if not ops:
- return expr
- return nodes.Compare(expr, ops, lineno=lineno)
-
- def parse_add(self):
- lineno = self.stream.current.lineno
- left = self.parse_sub()
- while self.stream.current.type == 'add':
- next(self.stream)
- right = self.parse_sub()
- left = nodes.Add(left, right, lineno=lineno)
- lineno = self.stream.current.lineno
- return left
-
- def parse_sub(self):
- lineno = self.stream.current.lineno
- left = self.parse_concat()
- while self.stream.current.type == 'sub':
- next(self.stream)
- right = self.parse_concat()
- left = nodes.Sub(left, right, lineno=lineno)
- lineno = self.stream.current.lineno
- return left
-
- def parse_concat(self):
- lineno = self.stream.current.lineno
- args = [self.parse_mul()]
- while self.stream.current.type == 'tilde':
- next(self.stream)
- args.append(self.parse_mul())
- if len(args) == 1:
- return args[0]
- return nodes.Concat(args, lineno=lineno)
-
- def parse_mul(self):
- lineno = self.stream.current.lineno
- left = self.parse_div()
- while self.stream.current.type == 'mul':
- next(self.stream)
- right = self.parse_div()
- left = nodes.Mul(left, right, lineno=lineno)
- lineno = self.stream.current.lineno
- return left
-
- def parse_div(self):
- lineno = self.stream.current.lineno
- left = self.parse_floordiv()
- while self.stream.current.type == 'div':
- next(self.stream)
- right = self.parse_floordiv()
- left = nodes.Div(left, right, lineno=lineno)
- lineno = self.stream.current.lineno
- return left
-
- def parse_floordiv(self):
- lineno = self.stream.current.lineno
- left = self.parse_mod()
- while self.stream.current.type == 'floordiv':
- next(self.stream)
- right = self.parse_mod()
- left = nodes.FloorDiv(left, right, lineno=lineno)
- lineno = self.stream.current.lineno
- return left
-
- def parse_mod(self):
- lineno = self.stream.current.lineno
- left = self.parse_pow()
- while self.stream.current.type == 'mod':
- next(self.stream)
- right = self.parse_pow()
- left = nodes.Mod(left, right, lineno=lineno)
- lineno = self.stream.current.lineno
- return left
-
- def parse_pow(self):
- lineno = self.stream.current.lineno
- left = self.parse_unary()
- while self.stream.current.type == 'pow':
- next(self.stream)
- right = self.parse_unary()
- left = nodes.Pow(left, right, lineno=lineno)
- lineno = self.stream.current.lineno
- return left
-
- def parse_unary(self, with_filter=True):
- token_type = self.stream.current.type
- lineno = self.stream.current.lineno
- if token_type == 'sub':
- next(self.stream)
- node = nodes.Neg(self.parse_unary(False), lineno=lineno)
- elif token_type == 'add':
- next(self.stream)
- node = nodes.Pos(self.parse_unary(False), lineno=lineno)
- else:
- node = self.parse_primary()
- node = self.parse_postfix(node)
- if with_filter:
- node = self.parse_filter_expr(node)
- return node
-
- def parse_primary(self):
- token = self.stream.current
- if token.type == 'name':
- if token.value in ('true', 'false', 'True', 'False'):
- node = nodes.Const(token.value in ('true', 'True'),
- lineno=token.lineno)
- elif token.value in ('none', 'None'):
- node = nodes.Const(None, lineno=token.lineno)
- else:
- node = nodes.Name(token.value, 'load', lineno=token.lineno)
- next(self.stream)
- elif token.type == 'string':
- next(self.stream)
- buf = [token.value]
- lineno = token.lineno
- while self.stream.current.type == 'string':
- buf.append(self.stream.current.value)
- next(self.stream)
- node = nodes.Const(''.join(buf), lineno=lineno)
- elif token.type in ('integer', 'float'):
- next(self.stream)
- node = nodes.Const(token.value, lineno=token.lineno)
- elif token.type == 'lparen':
- next(self.stream)
- node = self.parse_tuple(explicit_parentheses=True)
- self.stream.expect('rparen')
- elif token.type == 'lbracket':
- node = self.parse_list()
- elif token.type == 'lbrace':
- node = self.parse_dict()
- else:
- self.fail("unexpected '%s'" % describe_token(token), token.lineno)
- return node
-
- def parse_tuple(self, simplified=False, with_condexpr=True,
- extra_end_rules=None, explicit_parentheses=False):
- """Works like `parse_expression` but if multiple expressions are
- delimited by a comma a :class:`~ambari_jinja2.nodes.Tuple` node is created.
- This method could also return a regular expression instead of a tuple
- if no commas where found.
-
- The default parsing mode is a full tuple. If `simplified` is `True`
- only names and literals are parsed. The `no_condexpr` parameter is
- forwarded to :meth:`parse_expression`.
-
- Because tuples do not require delimiters and may end in a bogus comma
- an extra hint is needed that marks the end of a tuple. For example
- for loops support tuples between `for` and `in`. In that case the
- `extra_end_rules` is set to ``['name:in']``.
-
- `explicit_parentheses` is true if the parsing was triggered by an
- expression in parentheses. This is used to figure out if an empty
- tuple is a valid expression or not.
- """
- lineno = self.stream.current.lineno
- if simplified:
- parse = self.parse_primary
- elif with_condexpr:
- parse = self.parse_expression
- else:
- parse = lambda: self.parse_expression(with_condexpr=False)
- args = []
- is_tuple = False
- while 1:
- if args:
- self.stream.expect('comma')
- if self.is_tuple_end(extra_end_rules):
- break
- args.append(parse())
- if self.stream.current.type == 'comma':
- is_tuple = True
- else:
- break
- lineno = self.stream.current.lineno
-
- if not is_tuple:
- if args:
- return args[0]
-
- # if we don't have explicit parentheses, an empty tuple is
- # not a valid expression. This would mean nothing (literally
- # nothing) in the spot of an expression would be an empty
- # tuple.
- if not explicit_parentheses:
- self.fail('Expected an expression, got \'%s\'' %
- describe_token(self.stream.current))
-
- return nodes.Tuple(args, 'load', lineno=lineno)
-
- def parse_list(self):
- token = self.stream.expect('lbracket')
- items = []
- while self.stream.current.type != 'rbracket':
- if items:
- self.stream.expect('comma')
- if self.stream.current.type == 'rbracket':
- break
- items.append(self.parse_expression())
- self.stream.expect('rbracket')
- return nodes.List(items, lineno=token.lineno)
-
- def parse_dict(self):
- token = self.stream.expect('lbrace')
- items = []
- while self.stream.current.type != 'rbrace':
- if items:
- self.stream.expect('comma')
- if self.stream.current.type == 'rbrace':
- break
- key = self.parse_expression()
- self.stream.expect('colon')
- value = self.parse_expression()
- items.append(nodes.Pair(key, value, lineno=key.lineno))
- self.stream.expect('rbrace')
- return nodes.Dict(items, lineno=token.lineno)
-
- def parse_postfix(self, node):
- while 1:
- token_type = self.stream.current.type
- if token_type == 'dot' or token_type == 'lbracket':
- node = self.parse_subscript(node)
- # calls are valid both after postfix expressions (getattr
- # and getitem) as well as filters and tests
- elif token_type == 'lparen':
- node = self.parse_call(node)
- else:
- break
- return node
-
- def parse_filter_expr(self, node):
- while 1:
- token_type = self.stream.current.type
- if token_type == 'pipe':
- node = self.parse_filter(node)
- elif token_type == 'name' and self.stream.current.value == 'is':
- node = self.parse_test(node)
- # calls are valid both after postfix expressions (getattr
- # and getitem) as well as filters and tests
- elif token_type == 'lparen':
- node = self.parse_call(node)
- else:
- break
- return node
-
- def parse_subscript(self, node):
- token = next(self.stream)
- if token.type == 'dot':
- attr_token = self.stream.current
- next(self.stream)
- if attr_token.type == 'name':
- return nodes.Getattr(node, attr_token.value, 'load',
- lineno=token.lineno)
- elif attr_token.type != 'integer':
- self.fail('expected name or number', attr_token.lineno)
- arg = nodes.Const(attr_token.value, lineno=attr_token.lineno)
- return nodes.Getitem(node, arg, 'load', lineno=token.lineno)
- if token.type == 'lbracket':
- priority_on_attribute = False
- args = []
- while self.stream.current.type != 'rbracket':
- if args:
- self.stream.expect('comma')
- args.append(self.parse_subscribed())
- self.stream.expect('rbracket')
- if len(args) == 1:
- arg = args[0]
- else:
- arg = nodes.Tuple(args, 'load', lineno=token.lineno)
- return nodes.Getitem(node, arg, 'load', lineno=token.lineno)
- self.fail('expected subscript expression', self.lineno)
-
- def parse_subscribed(self):
- lineno = self.stream.current.lineno
-
- if self.stream.current.type == 'colon':
- next(self.stream)
- args = [None]
- else:
- node = self.parse_expression()
- if self.stream.current.type != 'colon':
- return node
- next(self.stream)
- args = [node]
-
- if self.stream.current.type == 'colon':
- args.append(None)
- elif self.stream.current.type not in ('rbracket', 'comma'):
- args.append(self.parse_expression())
- else:
- args.append(None)
-
- if self.stream.current.type == 'colon':
- next(self.stream)
- if self.stream.current.type not in ('rbracket', 'comma'):
- args.append(self.parse_expression())
- else:
- args.append(None)
- else:
- args.append(None)
-
- return nodes.Slice(lineno=lineno, *args)
-
- def parse_call(self, node):
- token = self.stream.expect('lparen')
- args = []
- kwargs = []
- dyn_args = dyn_kwargs = None
- require_comma = False
-
- def ensure(expr):
- if not expr:
- self.fail('invalid syntax for function call expression',
- token.lineno)
-
- while self.stream.current.type != 'rparen':
- if require_comma:
- self.stream.expect('comma')
- # support for trailing comma
- if self.stream.current.type == 'rparen':
- break
- if self.stream.current.type == 'mul':
- ensure(dyn_args is None and dyn_kwargs is None)
- next(self.stream)
- dyn_args = self.parse_expression()
- elif self.stream.current.type == 'pow':
- ensure(dyn_kwargs is None)
- next(self.stream)
- dyn_kwargs = self.parse_expression()
- else:
- ensure(dyn_args is None and dyn_kwargs is None)
- if self.stream.current.type == 'name' and \
- self.stream.look().type == 'assign':
- key = self.stream.current.value
- self.stream.skip(2)
- value = self.parse_expression()
- kwargs.append(nodes.Keyword(key, value,
- lineno=value.lineno))
- else:
- ensure(not kwargs)
- args.append(self.parse_expression())
-
- require_comma = True
- self.stream.expect('rparen')
-
- if node is None:
- return args, kwargs, dyn_args, dyn_kwargs
- return nodes.Call(node, args, kwargs, dyn_args, dyn_kwargs,
- lineno=token.lineno)
-
- def parse_filter(self, node, start_inline=False):
- while self.stream.current.type == 'pipe' or start_inline:
- if not start_inline:
- next(self.stream)
- token = self.stream.expect('name')
- name = token.value
- while self.stream.current.type == 'dot':
- next(self.stream)
- name += '.' + self.stream.expect('name').value
- if self.stream.current.type == 'lparen':
- args, kwargs, dyn_args, dyn_kwargs = self.parse_call(None)
- else:
- args = []
- kwargs = []
- dyn_args = dyn_kwargs = None
- node = nodes.Filter(node, name, args, kwargs, dyn_args,
- dyn_kwargs, lineno=token.lineno)
- start_inline = False
- return node
-
- def parse_test(self, node):
- token = next(self.stream)
- if self.stream.current.test('name:not'):
- next(self.stream)
- negated = True
- else:
- negated = False
- name = self.stream.expect('name').value
- while self.stream.current.type == 'dot':
- next(self.stream)
- name += '.' + self.stream.expect('name').value
- dyn_args = dyn_kwargs = None
- kwargs = []
- if self.stream.current.type == 'lparen':
- args, kwargs, dyn_args, dyn_kwargs = self.parse_call(None)
- elif self.stream.current.type in ('name', 'string', 'integer',
- 'float', 'lparen', 'lbracket',
- 'lbrace') and not \
- self.stream.current.test_any('name:else', 'name:or',
- 'name:and'):
- if self.stream.current.test('name:is'):
- self.fail('You cannot chain multiple tests with is')
- args = [self.parse_expression()]
- else:
- args = []
- node = nodes.Test(node, name, args, kwargs, dyn_args,
- dyn_kwargs, lineno=token.lineno)
- if negated:
- node = nodes.Not(node, lineno=token.lineno)
- return node
-
- def subparse(self, end_tokens=None):
- body = []
- data_buffer = []
- add_data = data_buffer.append
-
- if end_tokens is not None:
- self._end_token_stack.append(end_tokens)
-
- def flush_data():
- if data_buffer:
- lineno = data_buffer[0].lineno
- body.append(nodes.Output(data_buffer[:], lineno=lineno))
- del data_buffer[:]
-
- try:
- while self.stream:
- token = self.stream.current
- if token.type == 'data':
- if token.value:
- add_data(nodes.TemplateData(token.value,
- lineno=token.lineno))
- next(self.stream)
- elif token.type == 'variable_begin':
- next(self.stream)
- add_data(self.parse_tuple(with_condexpr=True))
- self.stream.expect('variable_end')
- elif token.type == 'block_begin':
- flush_data()
- next(self.stream)
- if end_tokens is not None and \
- self.stream.current.test_any(*end_tokens):
- return body
- rv = self.parse_statement()
- if isinstance(rv, list):
- body.extend(rv)
- else:
- body.append(rv)
- self.stream.expect('block_end')
- else:
- raise AssertionError('internal parsing error')
-
- flush_data()
- finally:
- if end_tokens is not None:
- self._end_token_stack.pop()
-
- return body
-
- def parse(self):
- """Parse the whole template into a `Template` node."""
- result = nodes.Template(self.subparse(), lineno=1)
- result.set_environment(self.environment)
- return result
http://git-wip-us.apache.org/repos/asf/ambari/blob/570de228/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/runtime.py
----------------------------------------------------------------------
diff --git a/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/runtime.py b/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/runtime.py
deleted file mode 100644
index 0830132..0000000
--- a/ambari-common/src/main/python/ambari_jinja2/ambari_jinja2/runtime.py
+++ /dev/null
@@ -1,544 +0,0 @@
-# -*- coding: utf-8 -*-
-"""
- ambari_jinja2.runtime
- ~~~~~~~~~~~~~~
-
- Runtime helpers.
-
- :copyright: (c) 2010 by the Jinja Team.
- :license: BSD.
-"""
-import sys
-from itertools import chain, imap
-from ambari_jinja2.nodes import EvalContext, _context_function_types
-from ambari_jinja2.utils import Markup, partial, soft_unicode, escape, missing, \
- concat, internalcode, next, object_type_repr
-from ambari_jinja2.exceptions import UndefinedError, TemplateRuntimeError, \
- TemplateNotFound
-
-
-# these variables are exported to the template runtime
-__all__ = ['LoopContext', 'TemplateReference', 'Macro', 'Markup',
- 'TemplateRuntimeError', 'missing', 'concat', 'escape',
- 'markup_join', 'unicode_join', 'to_string', 'identity',
- 'TemplateNotFound']
-
-#: the name of the function that is used to convert something into
-#: a string. 2to3 will adopt that automatically and the generated
-#: code can take advantage of it.
-to_string = unicode
-
-#: the identity function. Useful for certain things in the environment
-identity = lambda x: x
-
-
-def markup_join(seq):
- """Concatenation that escapes if necessary and converts to unicode."""
- buf = []
- iterator = imap(soft_unicode, seq)
- for arg in iterator:
- buf.append(arg)
- if hasattr(arg, '__html__'):
- return Markup(u'').join(chain(buf, iterator))
- return concat(buf)
-
-
-def unicode_join(seq):
- """Simple args to unicode conversion and concatenation."""
- return concat(imap(unicode, seq))
-
-
-def new_context(environment, template_name, blocks, vars=None,
- shared=None, globals=None, locals=None):
- """Internal helper to for context creation."""
- if vars is None:
- vars = {}
- if shared:
- parent = vars
- else:
- parent = dict(globals or (), **vars)
- if locals:
- # if the parent is shared a copy should be created because
- # we don't want to modify the dict passed
- if shared:
- parent = dict(parent)
- for key, value in locals.iteritems():
- if key[:2] == 'l_' and value is not missing:
- parent[key[2:]] = value
- return Context(environment, parent, template_name, blocks)
-
-
-class TemplateReference(object):
- """The `self` in templates."""
-
- def __init__(self, context):
- self.__context = context
-
- def __getitem__(self, name):
- blocks = self.__context.blocks[name]
- wrap = self.__context.eval_ctx.autoescape and \
- Markup or (lambda x: x)
- return BlockReference(name, self.__context, blocks, 0)
-
- def __repr__(self):
- return '<%s %r>' % (
- self.__class__.__name__,
- self.__context.name
- )
-
-
-class Context(object):
- """The template context holds the variables of a template. It stores the
- values passed to the template and also the names the template exports.
- Creating instances is neither supported nor useful as it's created
- automatically at various stages of the template evaluation and should not
- be created by hand.
-
- The context is immutable. Modifications on :attr:`parent` **must not**
- happen and modifications on :attr:`vars` are allowed from generated
- template code only. Template filters and global functions marked as
- :func:`contextfunction`\s get the active context passed as first argument
- and are allowed to access the context read-only.
-
- The template context supports read only dict operations (`get`,
- `keys`, `values`, `items`, `iterkeys`, `itervalues`, `iteritems`,
- `__getitem__`, `__contains__`). Additionally there is a :meth:`resolve`
- method that doesn't fail with a `KeyError` but returns an
- :class:`Undefined` object for missing variables.
- """
- __slots__ = ('parent', 'vars', 'environment', 'eval_ctx', 'exported_vars',
- 'name', 'blocks', '__weakref__')
-
- def __init__(self, environment, parent, name, blocks):
- self.parent = parent
- self.vars = {}
- self.environment = environment
- self.eval_ctx = EvalContext(self.environment, name)
- self.exported_vars = set()
- self.name = name
-
- # create the initial mapping of blocks. Whenever template inheritance
- # takes place the runtime will update this mapping with the new blocks
- # from the template.
- self.blocks = dict((k, [v]) for k, v in blocks.iteritems())
-
- def super(self, name, current):
- """Render a parent block."""
- try:
- blocks = self.blocks[name]
- index = blocks.index(current) + 1
- blocks[index]
- except LookupError:
- return self.environment.undefined('there is no parent block '
- 'called %r.' % name,
- name='super')
- return BlockReference(name, self, blocks, index)
-
- def get(self, key, default=None):
- """Returns an item from the template context, if it doesn't exist
- `default` is returned.
- """
- try:
- return self[key]
- except KeyError:
- return default
-
- def resolve(self, key):
- """Looks up a variable like `__getitem__` or `get` but returns an
- :class:`Undefined` object with the name of the name looked up.
- """
- if key in self.vars:
- return self.vars[key]
- if key in self.parent:
- return self.parent[key]
- return self.environment.undefined(name=key)
-
- def get_exported(self):
- """Get a new dict with the exported variables."""
- return dict((k, self.vars[k]) for k in self.exported_vars)
-
- def get_all(self):
- """Return a copy of the complete context as dict including the
- exported variables.
- """
- return dict(self.parent, **self.vars)
-
- @internalcode
- def call(__self, __obj, *args, **kwargs):
- """Call the callable with the arguments and keyword arguments
- provided but inject the active context or environment as first
- argument if the callable is a :func:`contextfunction` or
- :func:`environmentfunction`.
- """
- if __debug__:
- __traceback_hide__ = True
- if isinstance(__obj, _context_function_types):
- if getattr(__obj, 'contextfunction', 0):
- args = (__self,) + args
- elif getattr(__obj, 'evalcontextfunction', 0):
- args = (__self.eval_ctx,) + args
- elif getattr(__obj, 'environmentfunction', 0):
- args = (__self.environment,) + args
- try:
- return __obj(*args, **kwargs)
- except StopIteration:
- return __self.environment.undefined('value was undefined because '
- 'a callable raised a '
- 'StopIteration exception')
-
- def derived(self, locals=None):
- """Internal helper function to create a derived context."""
- context = new_context(self.environment, self.name, {},
- self.parent, True, None, locals)
- context.eval_ctx = self.eval_ctx
- context.blocks.update((k, list(v)) for k, v in self.blocks.iteritems())
- return context
-
- def _all(meth):
- proxy = lambda self: getattr(self.get_all(), meth)()
- proxy.__doc__ = getattr(dict, meth).__doc__
- proxy.__name__ = meth
- return proxy
-
- keys = _all('keys')
- values = _all('values')
- items = _all('items')
-
- # not available on python 3
- if hasattr(dict, 'iterkeys'):
- iterkeys = _all('iterkeys')
- itervalues = _all('itervalues')
- iteritems = _all('iteritems')
- del _all
-
- def __contains__(self, name):
- return name in self.vars or name in self.parent
-
- def __getitem__(self, key):
- """Lookup a variable or raise `KeyError` if the variable is
- undefined.
- """
- item = self.resolve(key)
- if isinstance(item, Undefined):
- raise KeyError(key)
- return item
-
- def __repr__(self):
- return '<%s %s of %r>' % (
- self.__class__.__name__,
- repr(self.get_all()),
- self.name
- )
-
-
-# register the context as mapping if possible
-try:
- from collections import Mapping
- Mapping.register(Context)
-except ImportError:
- pass
-
-
-class BlockReference(object):
- """One block on a template reference."""
-
- def __init__(self, name, context, stack, depth):
- self.name = name
- self._context = context
- self._stack = stack
- self._depth = depth
-
- @property
- def super(self):
- """Super the block."""
- if self._depth + 1 >= len(self._stack):
- return self._context.environment. \
- undefined('there is no parent block called %r.' %
- self.name, name='super')
- return BlockReference(self.name, self._context, self._stack,
- self._depth + 1)
-
- @internalcode
- def __call__(self):
- rv = concat(self._stack[self._depth](self._context))
- if self._context.eval_ctx.autoescape:
- rv = Markup(rv)
- return rv
-
-
-class LoopContext(object):
- """A loop context for dynamic iteration."""
-
- def __init__(self, iterable, recurse=None):
- self._iterator = iter(iterable)
- self._recurse = recurse
- self.index0 = -1
-
- # try to get the length of the iterable early. This must be done
- # here because there are some broken iterators around where there
- # __len__ is the number of iterations left (i'm looking at your
- # listreverseiterator!).
- try:
- self._length = len(iterable)
- except (TypeError, AttributeError):
- self._length = None
-
- def cycle(self, *args):
- """Cycles among the arguments with the current loop index."""
- if not args:
- raise TypeError('no items for cycling given')
- return args[self.index0 % len(args)]
-
- first = property(lambda x: x.index0 == 0)
- last = property(lambda x: x.index0 + 1 == x.length)
- index = property(lambda x: x.index0 + 1)
- revindex = property(lambda x: x.length - x.index0)
- revindex0 = property(lambda x: x.length - x.index)
-
- def __len__(self):
- return self.length
-
- def __iter__(self):
- return LoopContextIterator(self)
-
- @internalcode
- def loop(self, iterable):
- if self._recurse is None:
- raise TypeError('Tried to call non recursive loop. Maybe you '
- "forgot the 'recursive' modifier.")
- return self._recurse(iterable, self._recurse)
-
- # a nifty trick to enhance the error message if someone tried to call
- # the the loop without or with too many arguments.
- __call__ = loop
- del loop
-
- @property
- def length(self):
- if self._length is None:
- # if was not possible to get the length of the iterator when
- # the loop context was created (ie: iterating over a generator)
- # we have to convert the iterable into a sequence and use the
- # length of that.
- iterable = tuple(self._iterator)
- self._iterator = iter(iterable)
- self._length = len(iterable) + self.index0 + 1
- return self._length
-
- def __repr__(self):
- return '<%s %r/%r>' % (
- self.__class__.__name__,
- self.index,
- self.length
- )
-
-
-class LoopContextIterator(object):
- """The iterator for a loop context."""
- __slots__ = ('context',)
-
- def __init__(self, context):
- self.context = context
-
- def __iter__(self):
- return self
-
- def next(self):
- ctx = self.context
- ctx.index0 += 1
- return next(ctx._iterator), ctx
-
-
-class Macro(object):
- """Wraps a macro function."""
-
- def __init__(self, environment, func, name, arguments, defaults,
- catch_kwargs, catch_varargs, caller):
- self._environment = environment
- self._func = func
- self._argument_count = len(arguments)
- self.name = name
- self.arguments = arguments
- self.defaults = defaults
- self.catch_kwargs = catch_kwargs
- self.catch_varargs = catch_varargs
- self.caller = caller
-
- @internalcode
- def __call__(self, *args, **kwargs):
- # try to consume the positional arguments
- arguments = list(args[:self._argument_count])
- off = len(arguments)
-
- # if the number of arguments consumed is not the number of
- # arguments expected we start filling in keyword arguments
- # and defaults.
- if off != self._argument_count:
- for idx, name in enumerate(self.arguments[len(arguments):]):
- try:
- value = kwargs.pop(name)
- except KeyError:
- try:
- value = self.defaults[idx - self._argument_count + off]
- except IndexError:
- value = self._environment.undefined(
- 'parameter %r was not provided' % name, name=name)
- arguments.append(value)
-
- # it's important that the order of these arguments does not change
- # if not also changed in the compiler's `function_scoping` method.
- # the order is caller, keyword arguments, positional arguments!
- if self.caller:
- caller = kwargs.pop('caller', None)
- if caller is None:
- caller = self._environment.undefined('No caller defined',
- name='caller')
- arguments.append(caller)
- if self.catch_kwargs:
- arguments.append(kwargs)
- elif kwargs:
- raise TypeError('macro %r takes no keyword argument %r' %
- (self.name, next(iter(kwargs))))
- if self.catch_varargs:
- arguments.append(args[self._argument_count:])
- elif len(args) > self._argument_count:
- raise TypeError('macro %r takes not more than %d argument(s)' %
- (self.name, len(self.arguments)))
- return self._func(*arguments)
-
- def __repr__(self):
- return '<%s %s>' % (
- self.__class__.__name__,
- self.name is None and 'anonymous' or repr(self.name)
- )
-
-
-class Undefined(object):
- """The default undefined type. This undefined type can be printed and
- iterated over, but every other access will raise an :exc:`UndefinedError`:
-
- >>> foo = Undefined(name='foo')
- >>> str(foo)
- ''
- >>> not foo
- True
- >>> foo + 42
- Traceback (most recent call last):
- ...
- UndefinedError: 'foo' is undefined
- """
- __slots__ = ('_undefined_hint', '_undefined_obj', '_undefined_name',
- '_undefined_exception')
-
- def __init__(self, hint=None, obj=missing, name=None, exc=UndefinedError):
- self._undefined_hint = hint
- self._undefined_obj = obj
- self._undefined_name = name
- self._undefined_exception = exc
-
- @internalcode
- def _fail_with_undefined_error(self, *args, **kwargs):
- """Regular callback function for undefined objects that raises an
- `UndefinedError` on call.
- """
- if self._undefined_hint is None:
- if self._undefined_obj is missing:
- hint = '%r is undefined' % self._undefined_name
- elif not isinstance(self._undefined_name, basestring):
- hint = '%s has no element %r' % (
- object_type_repr(self._undefined_obj),
- self._undefined_name
- )
- else:
- hint = '%r has no attribute %r' % (
- object_type_repr(self._undefined_obj),
- self._undefined_name
- )
- else:
- hint = self._undefined_hint
- raise self._undefined_exception(hint)
-
- __add__ = __radd__ = __mul__ = __rmul__ = __div__ = __rdiv__ = \
- __truediv__ = __rtruediv__ = __floordiv__ = __rfloordiv__ = \
- __mod__ = __rmod__ = __pos__ = __neg__ = __call__ = \
- __getattr__ = __getitem__ = __lt__ = __le__ = __gt__ = __ge__ = \
- __int__ = __float__ = __complex__ = __pow__ = __rpow__ = \
- _fail_with_undefined_error
-
- def __str__(self):
- return unicode(self).encode('utf-8')
-
- # unicode goes after __str__ because we configured 2to3 to rename
- # __unicode__ to __str__. because the 2to3 tree is not designed to
- # remove nodes from it, we leave the above __str__ around and let
- # it override at runtime.
- def __unicode__(self):
- return u''
-
- def __len__(self):
- return 0
-
- def __iter__(self):
- if 0:
- yield None
-
- def __nonzero__(self):
- return False
-
- def __repr__(self):
- return 'Undefined'
-
-
-class DebugUndefined(Undefined):
- """An undefined that returns the debug info when printed.
-
- >>> foo = DebugUndefined(name='foo')
- >>> str(foo)
- '{{ foo }}'
- >>> not foo
- True
- >>> foo + 42
- Traceback (most recent call last):
- ...
- UndefinedError: 'foo' is undefined
- """
- __slots__ = ()
-
- def __unicode__(self):
- if self._undefined_hint is None:
- if self._undefined_obj is missing:
- return u'{{ %s }}' % self._undefined_name
- return '{{ no such element: %s[%r] }}' % (
- object_type_repr(self._undefined_obj),
- self._undefined_name
- )
- return u'{{ undefined value printed: %s }}' % self._undefined_hint
-
-
-class StrictUndefined(Undefined):
- """An undefined that barks on print and iteration as well as boolean
- tests and all kinds of comparisons. In other words: you can do nothing
- with it except checking if it's defined using the `defined` test.
-
- >>> foo = StrictUndefined(name='foo')
- >>> str(foo)
- Traceback (most recent call last):
- ...
- UndefinedError: 'foo' is undefined
- >>> not foo
- Traceback (most recent call last):
- ...
- UndefinedError: 'foo' is undefined
- >>> foo + 42
- Traceback (most recent call last):
- ...
- UndefinedError: 'foo' is undefined
- """
- __slots__ = ()
- __iter__ = __unicode__ = __str__ = __len__ = __nonzero__ = __eq__ = \
- __ne__ = __bool__ = Undefined._fail_with_undefined_error
-
-
-# remove remaining slots attributes, after the metaclass did the magic they
-# are unneeded and irritating as they contain wrong data for the subclasses.
-del Undefined.__slots__, DebugUndefined.__slots__, StrictUndefined.__slots__