From 2db58930a6f8c955c4d437657bd07e2939a705f2 Mon Sep 17 00:00:00 2001 From: James Taylor Date: Sun, 16 Jun 2019 16:16:03 -0700 Subject: Convert watch page to flask framework --- python/jinja2/compiler.py | 1721 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1721 insertions(+) create mode 100644 python/jinja2/compiler.py (limited to 'python/jinja2/compiler.py') diff --git a/python/jinja2/compiler.py b/python/jinja2/compiler.py new file mode 100644 index 0000000..d534a82 --- /dev/null +++ b/python/jinja2/compiler.py @@ -0,0 +1,1721 @@ +# -*- coding: utf-8 -*- +""" + jinja2.compiler + ~~~~~~~~~~~~~~~ + + Compiles nodes into python code. + + :copyright: (c) 2017 by the Jinja Team. + :license: BSD, see LICENSE for more details. +""" +from itertools import chain +from copy import deepcopy +from keyword import iskeyword as is_python_keyword +from functools import update_wrapper +from jinja2 import nodes +from jinja2.nodes import EvalContext +from jinja2.visitor import NodeVisitor +from jinja2.optimizer import Optimizer +from jinja2.exceptions import TemplateAssertionError +from jinja2.utils import Markup, concat, escape +from jinja2._compat import range_type, text_type, string_types, \ + iteritems, NativeStringIO, imap, izip +from jinja2.idtracking import Symbols, VAR_LOAD_PARAMETER, \ + VAR_LOAD_RESOLVE, VAR_LOAD_ALIAS, VAR_LOAD_UNDEFINED + + +operators = { + 'eq': '==', + 'ne': '!=', + 'gt': '>', + 'gteq': '>=', + 'lt': '<', + 'lteq': '<=', + 'in': 'in', + 'notin': 'not in' +} + +# what method to iterate over items do we want to use for dict iteration +# in generated code? on 2.x let's go with iteritems, on 3.x with items +if hasattr(dict, 'iteritems'): + dict_item_iter = 'iteritems' +else: + dict_item_iter = 'items' + +code_features = ['division'] + +# does this python version support generator stops? (PEP 0479) +try: + exec('from __future__ import generator_stop') + code_features.append('generator_stop') +except SyntaxError: + pass + +# does this python version support yield from? +try: + exec('def f(): yield from x()') +except SyntaxError: + supports_yield_from = False +else: + supports_yield_from = True + + +def optimizeconst(f): + def new_func(self, node, frame, **kwargs): + # Only optimize if the frame is not volatile + if self.optimized and not frame.eval_ctx.volatile: + new_node = self.optimizer.visit(node, frame.eval_ctx) + if new_node != node: + return self.visit(new_node, frame) + return f(self, node, frame, **kwargs) + return update_wrapper(new_func, f) + + +def generate(node, environment, name, filename, stream=None, + defer_init=False, optimized=True): + """Generate the python source for a node tree.""" + if not isinstance(node, nodes.Template): + raise TypeError('Can\'t compile non template nodes') + generator = environment.code_generator_class(environment, name, filename, + stream, defer_init, + optimized) + generator.visit(node) + if stream is None: + return generator.stream.getvalue() + + +def has_safe_repr(value): + """Does the node have a safe representation?""" + if value is None or value is NotImplemented or value is Ellipsis: + return True + if type(value) in (bool, int, float, complex, range_type, Markup) + string_types: + return True + if type(value) in (tuple, list, set, frozenset): + for item in value: + if not has_safe_repr(item): + return False + return True + elif type(value) is dict: + for key, value in iteritems(value): + if not has_safe_repr(key): + return False + if not has_safe_repr(value): + return False + return True + return False + + +def find_undeclared(nodes, names): + """Check if the names passed are accessed undeclared. The return value + is a set of all the undeclared names from the sequence of names found. + """ + visitor = UndeclaredNameVisitor(names) + try: + for node in nodes: + visitor.visit(node) + except VisitorExit: + pass + return visitor.undeclared + + +class MacroRef(object): + + def __init__(self, node): + self.node = node + self.accesses_caller = False + self.accesses_kwargs = False + self.accesses_varargs = False + + +class Frame(object): + """Holds compile time information for us.""" + + def __init__(self, eval_ctx, parent=None, level=None): + self.eval_ctx = eval_ctx + self.symbols = Symbols(parent and parent.symbols or None, + level=level) + + # a toplevel frame is the root + soft frames such as if conditions. + self.toplevel = False + + # the root frame is basically just the outermost frame, so no if + # conditions. This information is used to optimize inheritance + # situations. + self.rootlevel = False + + # in some dynamic inheritance situations the compiler needs to add + # write tests around output statements. + self.require_output_check = parent and parent.require_output_check + + # inside some tags we are using a buffer rather than yield statements. + # this for example affects {% filter %} or {% macro %}. If a frame + # is buffered this variable points to the name of the list used as + # buffer. + self.buffer = None + + # the name of the block we're in, otherwise None. + self.block = parent and parent.block or None + + # the parent of this frame + self.parent = parent + + if parent is not None: + self.buffer = parent.buffer + + def copy(self): + """Create a copy of the current one.""" + rv = object.__new__(self.__class__) + rv.__dict__.update(self.__dict__) + rv.symbols = self.symbols.copy() + return rv + + def inner(self, isolated=False): + """Return an inner frame.""" + if isolated: + return Frame(self.eval_ctx, level=self.symbols.level + 1) + return Frame(self.eval_ctx, self) + + def soft(self): + """Return a soft frame. A soft frame may not be modified as + standalone thing as it shares the resources with the frame it + was created of, but it's not a rootlevel frame any longer. + + This is only used to implement if-statements. + """ + rv = self.copy() + rv.rootlevel = False + return rv + + __copy__ = copy + + +class VisitorExit(RuntimeError): + """Exception used by the `UndeclaredNameVisitor` to signal a stop.""" + + +class DependencyFinderVisitor(NodeVisitor): + """A visitor that collects filter and test calls.""" + + def __init__(self): + self.filters = set() + self.tests = set() + + def visit_Filter(self, node): + self.generic_visit(node) + self.filters.add(node.name) + + def visit_Test(self, node): + self.generic_visit(node) + self.tests.add(node.name) + + def visit_Block(self, node): + """Stop visiting at blocks.""" + + +class UndeclaredNameVisitor(NodeVisitor): + """A visitor that checks if a name is accessed without being + declared. This is different from the frame visitor as it will + not stop at closure frames. + """ + + def __init__(self, names): + self.names = set(names) + self.undeclared = set() + + def visit_Name(self, node): + if node.ctx == 'load' and node.name in self.names: + self.undeclared.add(node.name) + if self.undeclared == self.names: + raise VisitorExit() + else: + self.names.discard(node.name) + + def visit_Block(self, node): + """Stop visiting a blocks.""" + + +class CompilerExit(Exception): + """Raised if the compiler encountered a situation where it just + doesn't make sense to further process the code. Any block that + raises such an exception is not further processed. + """ + + +class CodeGenerator(NodeVisitor): + + def __init__(self, environment, name, filename, stream=None, + defer_init=False, optimized=True): + if stream is None: + stream = NativeStringIO() + self.environment = environment + self.name = name + self.filename = filename + self.stream = stream + self.created_block_context = False + self.defer_init = defer_init + self.optimized = optimized + if optimized: + self.optimizer = Optimizer(environment) + + # aliases for imports + self.import_aliases = {} + + # a registry for all blocks. Because blocks are moved out + # into the global python scope they are registered here + self.blocks = {} + + # the number of extends statements so far + self.extends_so_far = 0 + + # some templates have a rootlevel extends. In this case we + # can safely assume that we're a child template and do some + # more optimizations. + self.has_known_extends = False + + # the current line number + self.code_lineno = 1 + + # registry of all filters and tests (global, not block local) + self.tests = {} + self.filters = {} + + # the debug information + self.debug_info = [] + self._write_debug_info = None + + # the number of new lines before the next write() + self._new_lines = 0 + + # the line number of the last written statement + self._last_line = 0 + + # true if nothing was written so far. + self._first_write = True + + # used by the `temporary_identifier` method to get new + # unique, temporary identifier + self._last_identifier = 0 + + # the current indentation + self._indentation = 0 + + # Tracks toplevel assignments + self._assign_stack = [] + + # Tracks parameter definition blocks + self._param_def_block = [] + + # Tracks the current context. + self._context_reference_stack = ['context'] + + # -- Various compilation helpers + + def fail(self, msg, lineno): + """Fail with a :exc:`TemplateAssertionError`.""" + raise TemplateAssertionError(msg, lineno, self.name, self.filename) + + def temporary_identifier(self): + """Get a new unique identifier.""" + self._last_identifier += 1 + return 't_%d' % self._last_identifier + + def buffer(self, frame): + """Enable buffering for the frame from that point onwards.""" + frame.buffer = self.temporary_identifier() + self.writeline('%s = []' % frame.buffer) + + def return_buffer_contents(self, frame, force_unescaped=False): + """Return the buffer contents of the frame.""" + if not force_unescaped: + if frame.eval_ctx.volatile: + self.writeline('if context.eval_ctx.autoescape:') + self.indent() + self.writeline('return Markup(concat(%s))' % frame.buffer) + self.outdent() + self.writeline('else:') + self.indent() + self.writeline('return concat(%s)' % frame.buffer) + self.outdent() + return + elif frame.eval_ctx.autoescape: + self.writeline('return Markup(concat(%s))' % frame.buffer) + return + self.writeline('return concat(%s)' % frame.buffer) + + def indent(self): + """Indent by one.""" + self._indentation += 1 + + def outdent(self, step=1): + """Outdent by step.""" + self._indentation -= step + + def start_write(self, frame, node=None): + """Yield or write into the frame buffer.""" + if frame.buffer is None: + self.writeline('yield ', node) + else: + self.writeline('%s.append(' % frame.buffer, node) + + def end_write(self, frame): + """End the writing process started by `start_write`.""" + if frame.buffer is not None: + self.write(')') + + def simple_write(self, s, frame, node=None): + """Simple shortcut for start_write + write + end_write.""" + self.start_write(frame, node) + self.write(s) + self.end_write(frame) + + def blockvisit(self, nodes, frame): + """Visit a list of nodes as block in a frame. If the current frame + is no buffer a dummy ``if 0: yield None`` is written automatically. + """ + try: + self.writeline('pass') + for node in nodes: + self.visit(node, frame) + except CompilerExit: + pass + + def write(self, x): + """Write a string into the output stream.""" + if self._new_lines: + if not self._first_write: + self.stream.write('\n' * self._new_lines) + self.code_lineno += self._new_lines + if self._write_debug_info is not None: + self.debug_info.append((self._write_debug_info, + self.code_lineno)) + self._write_debug_info = None + self._first_write = False + self.stream.write(' ' * self._indentation) + self._new_lines = 0 + self.stream.write(x) + + def writeline(self, x, node=None, extra=0): + """Combination of newline and write.""" + self.newline(node, extra) + self.write(x) + + def newline(self, node=None, extra=0): + """Add one or more newlines before the next write.""" + self._new_lines = max(self._new_lines, 1 + extra) + if node is not None and node.lineno != self._last_line: + self._write_debug_info = node.lineno + self._last_line = node.lineno + + def signature(self, node, frame, extra_kwargs=None): + """Writes a function call to the stream for the current node. + A leading comma is added automatically. The extra keyword + arguments may not include python keywords otherwise a syntax + error could occour. The extra keyword arguments should be given + as python dict. + """ + # if any of the given keyword arguments is a python keyword + # we have to make sure that no invalid call is created. + kwarg_workaround = False + for kwarg in chain((x.key for x in node.kwargs), extra_kwargs or ()): + if is_python_keyword(kwarg): + kwarg_workaround = True + break + + for arg in node.args: + self.write(', ') + self.visit(arg, frame) + + if not kwarg_workaround: + for kwarg in node.kwargs: + self.write(', ') + self.visit(kwarg, frame) + if extra_kwargs is not None: + for key, value in iteritems(extra_kwargs): + self.write(', %s=%s' % (key, value)) + if node.dyn_args: + self.write(', *') + self.visit(node.dyn_args, frame) + + if kwarg_workaround: + if node.dyn_kwargs is not None: + self.write(', **dict({') + else: + self.write(', **{') + for kwarg in node.kwargs: + self.write('%r: ' % kwarg.key) + self.visit(kwarg.value, frame) + self.write(', ') + if extra_kwargs is not None: + for key, value in iteritems(extra_kwargs): + self.write('%r: %s, ' % (key, value)) + if node.dyn_kwargs is not None: + self.write('}, **') + self.visit(node.dyn_kwargs, frame) + self.write(')') + else: + self.write('}') + + elif node.dyn_kwargs is not None: + self.write(', **') + self.visit(node.dyn_kwargs, frame) + + def pull_dependencies(self, nodes): + """Pull all the dependencies.""" + visitor = DependencyFinderVisitor() + for node in nodes: + visitor.visit(node) + for dependency in 'filters', 'tests': + mapping = getattr(self, dependency) + for name in getattr(visitor, dependency): + if name not in mapping: + mapping[name] = self.temporary_identifier() + self.writeline('%s = environment.%s[%r]' % + (mapping[name], dependency, name)) + + def enter_frame(self, frame): + undefs = [] + for target, (action, param) in iteritems(frame.symbols.loads): + if action == VAR_LOAD_PARAMETER: + pass + elif action == VAR_LOAD_RESOLVE: + self.writeline('%s = %s(%r)' % + (target, self.get_resolve_func(), param)) + elif action == VAR_LOAD_ALIAS: + self.writeline('%s = %s' % (target, param)) + elif action == VAR_LOAD_UNDEFINED: + undefs.append(target) + else: + raise NotImplementedError('unknown load instruction') + if undefs: + self.writeline('%s = missing' % ' = '.join(undefs)) + + def leave_frame(self, frame, with_python_scope=False): + if not with_python_scope: + undefs = [] + for target, _ in iteritems(frame.symbols.loads): + undefs.append(target) + if undefs: + self.writeline('%s = missing' % ' = '.join(undefs)) + + def func(self, name): + if self.environment.is_async: + return 'async def %s' % name + return 'def %s' % name + + def macro_body(self, node, frame): + """Dump the function def of a macro or call block.""" + frame = frame.inner() + frame.symbols.analyze_node(node) + macro_ref = MacroRef(node) + + explicit_caller = None + skip_special_params = set() + args = [] + for idx, arg in enumerate(node.args): + if arg.name == 'caller': + explicit_caller = idx + if arg.name in ('kwargs', 'varargs'): + skip_special_params.add(arg.name) + args.append(frame.symbols.ref(arg.name)) + + undeclared = find_undeclared(node.body, ('caller', 'kwargs', 'varargs')) + + if 'caller' in undeclared: + # In older Jinja2 versions there was a bug that allowed caller + # to retain the special behavior even if it was mentioned in + # the argument list. However thankfully this was only really + # working if it was the last argument. So we are explicitly + # checking this now and error out if it is anywhere else in + # the argument list. + if explicit_caller is not None: + try: + node.defaults[explicit_caller - len(node.args)] + except IndexError: + self.fail('When defining macros or call blocks the ' + 'special "caller" argument must be omitted ' + 'or be given a default.', node.lineno) + else: + args.append(frame.symbols.declare_parameter('caller')) + macro_ref.accesses_caller = True + if 'kwargs' in undeclared and not 'kwargs' in skip_special_params: + args.append(frame.symbols.declare_parameter('kwargs')) + macro_ref.accesses_kwargs = True + if 'varargs' in undeclared and not 'varargs' in skip_special_params: + args.append(frame.symbols.declare_parameter('varargs')) + macro_ref.accesses_varargs = True + + # macros are delayed, they never require output checks + frame.require_output_check = False + frame.symbols.analyze_node(node) + self.writeline('%s(%s):' % (self.func('macro'), ', '.join(args)), node) + self.indent() + + self.buffer(frame) + self.enter_frame(frame) + + self.push_parameter_definitions(frame) + for idx, arg in enumerate(node.args): + ref = frame.symbols.ref(arg.name) + self.writeline('if %s is missing:' % ref) + self.indent() + try: + default = node.defaults[idx - len(node.args)] + except IndexError: + self.writeline('%s = undefined(%r, name=%r)' % ( + ref, + 'parameter %r was not provided' % arg.name, + arg.name)) + else: + self.writeline('%s = ' % ref) + self.visit(default, frame) + self.mark_parameter_stored(ref) + self.outdent() + self.pop_parameter_definitions() + + self.blockvisit(node.body, frame) + self.return_buffer_contents(frame, force_unescaped=True) + self.leave_frame(frame, with_python_scope=True) + self.outdent() + + return frame, macro_ref + + def macro_def(self, macro_ref, frame): + """Dump the macro definition for the def created by macro_body.""" + arg_tuple = ', '.join(repr(x.name) for x in macro_ref.node.args) + name = getattr(macro_ref.node, 'name', None) + if len(macro_ref.node.args) == 1: + arg_tuple += ',' + self.write('Macro(environment, macro, %r, (%s), %r, %r, %r, ' + 'context.eval_ctx.autoescape)' % + (name, arg_tuple, macro_ref.accesses_kwargs, + macro_ref.accesses_varargs, macro_ref.accesses_caller)) + + def position(self, node): + """Return a human readable position for the node.""" + rv = 'line %d' % node.lineno + if self.name is not None: + rv += ' in ' + repr(self.name) + return rv + + def dump_local_context(self, frame): + return '{%s}' % ', '.join( + '%r: %s' % (name, target) for name, target + in iteritems(frame.symbols.dump_stores())) + + def write_commons(self): + """Writes a common preamble that is used by root and block functions. + Primarily this sets up common local helpers and enforces a generator + through a dead branch. + """ + self.writeline('resolve = context.resolve_or_missing') + self.writeline('undefined = environment.undefined') + self.writeline('if 0: yield None') + + def push_parameter_definitions(self, frame): + """Pushes all parameter targets from the given frame into a local + stack that permits tracking of yet to be assigned parameters. In + particular this enables the optimization from `visit_Name` to skip + undefined expressions for parameters in macros as macros can reference + otherwise unbound parameters. + """ + self._param_def_block.append(frame.symbols.dump_param_targets()) + + def pop_parameter_definitions(self): + """Pops the current parameter definitions set.""" + self._param_def_block.pop() + + def mark_parameter_stored(self, target): + """Marks a parameter in the current parameter definitions as stored. + This will skip the enforced undefined checks. + """ + if self._param_def_block: + self._param_def_block[-1].discard(target) + + def push_context_reference(self, target): + self._context_reference_stack.append(target) + + def pop_context_reference(self): + self._context_reference_stack.pop() + + def get_context_ref(self): + return self._context_reference_stack[-1] + + def get_resolve_func(self): + target = self._context_reference_stack[-1] + if target == 'context': + return 'resolve' + return '%s.resolve' % target + + def derive_context(self, frame): + return '%s.derived(%s)' % ( + self.get_context_ref(), + self.dump_local_context(frame), + ) + + def parameter_is_undeclared(self, target): + """Checks if a given target is an undeclared parameter.""" + if not self._param_def_block: + return False + return target in self._param_def_block[-1] + + def push_assign_tracking(self): + """Pushes a new layer for assignment tracking.""" + self._assign_stack.append(set()) + + def pop_assign_tracking(self, frame): + """Pops the topmost level for assignment tracking and updates the + context variables if necessary. + """ + vars = self._assign_stack.pop() + if not frame.toplevel or not vars: + return + public_names = [x for x in vars if x[:1] != '_'] + if len(vars) == 1: + name = next(iter(vars)) + ref = frame.symbols.ref(name) + self.writeline('context.vars[%r] = %s' % (name, ref)) + else: + self.writeline('context.vars.update({') + for idx, name in enumerate(vars): + if idx: + self.write(', ') + ref = frame.symbols.ref(name) + self.write('%r: %s' % (name, ref)) + self.write('})') + if public_names: + if len(public_names) == 1: + self.writeline('context.exported_vars.add(%r)' % + public_names[0]) + else: + self.writeline('context.exported_vars.update((%s))' % + ', '.join(imap(repr, public_names))) + + # -- Statement Visitors + + def visit_Template(self, node, frame=None): + assert frame is None, 'no root frame allowed' + eval_ctx = EvalContext(self.environment, self.name) + + from jinja2.runtime import __all__ as exported + self.writeline('from __future__ import %s' % ', '.join(code_features)) + self.writeline('from jinja2.runtime import ' + ', '.join(exported)) + + if self.environment.is_async: + self.writeline('from jinja2.asyncsupport import auto_await, ' + 'auto_aiter, make_async_loop_context') + + # if we want a deferred initialization we cannot move the + # environment into a local name + envenv = not self.defer_init and ', environment=environment' or '' + + # do we have an extends tag at all? If not, we can save some + # overhead by just not processing any inheritance code. + have_extends = node.find(nodes.Extends) is not None + + # find all blocks + for block in node.find_all(nodes.Block): + if block.name in self.blocks: + self.fail('block %r defined twice' % block.name, block.lineno) + self.blocks[block.name] = block + + # find all imports and import them + for import_ in node.find_all(nodes.ImportedName): + if import_.importname not in self.import_aliases: + imp = import_.importname + self.import_aliases[imp] = alias = self.temporary_identifier() + if '.' in imp: + module, obj = imp.rsplit('.', 1) + self.writeline('from %s import %s as %s' % + (module, obj, alias)) + else: + self.writeline('import %s as %s' % (imp, alias)) + + # add the load name + self.writeline('name = %r' % self.name) + + # generate the root render function. + self.writeline('%s(context, missing=missing%s):' % + (self.func('root'), envenv), extra=1) + self.indent() + self.write_commons() + + # process the root + frame = Frame(eval_ctx) + if 'self' in find_undeclared(node.body, ('self',)): + ref = frame.symbols.declare_parameter('self') + self.writeline('%s = TemplateReference(context)' % ref) + frame.symbols.analyze_node(node) + frame.toplevel = frame.rootlevel = True + frame.require_output_check = have_extends and not self.has_known_extends + if have_extends: + self.writeline('parent_template = None') + self.enter_frame(frame) + self.pull_dependencies(node.body) + self.blockvisit(node.body, frame) + self.leave_frame(frame, with_python_scope=True) + self.outdent() + + # make sure that the parent root is called. + if have_extends: + if not self.has_known_extends: + self.indent() + self.writeline('if parent_template is not None:') + self.indent() + if supports_yield_from and not self.environment.is_async: + self.writeline('yield from parent_template.' + 'root_render_func(context)') + else: + self.writeline('%sfor event in parent_template.' + 'root_render_func(context):' % + (self.environment.is_async and 'async ' or '')) + self.indent() + self.writeline('yield event') + self.outdent() + self.outdent(1 + (not self.has_known_extends)) + + # at this point we now have the blocks collected and can visit them too. + for name, block in iteritems(self.blocks): + self.writeline('%s(context, missing=missing%s):' % + (self.func('block_' + name), envenv), + block, 1) + self.indent() + self.write_commons() + # It's important that we do not make this frame a child of the + # toplevel template. This would cause a variety of + # interesting issues with identifier tracking. + block_frame = Frame(eval_ctx) + undeclared = find_undeclared(block.body, ('self', 'super')) + if 'self' in undeclared: + ref = block_frame.symbols.declare_parameter('self') + self.writeline('%s = TemplateReference(context)' % ref) + if 'super' in undeclared: + ref = block_frame.symbols.declare_parameter('super') + self.writeline('%s = context.super(%r, ' + 'block_%s)' % (ref, name, name)) + block_frame.symbols.analyze_node(block) + block_frame.block = name + self.enter_frame(block_frame) + self.pull_dependencies(block.body) + self.blockvisit(block.body, block_frame) + self.leave_frame(block_frame, with_python_scope=True) + self.outdent() + + self.writeline('blocks = {%s}' % ', '.join('%r: block_%s' % (x, x) + for x in self.blocks), + extra=1) + + # add a function that returns the debug info + self.writeline('debug_info = %r' % '&'.join('%s=%s' % x for x + in self.debug_info)) + + def visit_Block(self, node, frame): + """Call a block and register it for the template.""" + level = 0 + if frame.toplevel: + # if we know that we are a child template, there is no need to + # check if we are one + if self.has_known_extends: + return + if self.extends_so_far > 0: + self.writeline('if parent_template is None:') + self.indent() + level += 1 + + if node.scoped: + context = self.derive_context(frame) + else: + context = self.get_context_ref() + + if supports_yield_from and not self.environment.is_async and \ + frame.buffer is None: + self.writeline('yield from context.blocks[%r][0](%s)' % ( + node.name, context), node) + else: + loop = self.environment.is_async and 'async for' or 'for' + self.writeline('%s event in context.blocks[%r][0](%s):' % ( + loop, node.name, context), node) + self.indent() + self.simple_write('event', frame) + self.outdent() + + self.outdent(level) + + def visit_Extends(self, node, frame): + """Calls the extender.""" + if not frame.toplevel: + self.fail('cannot use extend from a non top-level scope', + node.lineno) + + # if the number of extends statements in general is zero so + # far, we don't have to add a check if something extended + # the template before this one. + if self.extends_so_far > 0: + + # if we have a known extends we just add a template runtime + # error into the generated code. We could catch that at compile + # time too, but i welcome it not to confuse users by throwing the + # same error at different times just "because we can". + if not self.has_known_extends: + self.writeline('if parent_template is not None:') + self.indent() + self.writeline('raise TemplateRuntimeError(%r)' % + 'extended multiple times') + + # if we have a known extends already we don't need that code here + # as we know that the template execution will end here. + if self.has_known_extends: + raise CompilerExit() + else: + self.outdent() + + self.writeline('parent_template = environment.get_template(', node) + self.visit(node.template, frame) + self.write(', %r)' % self.name) + self.writeline('for name, parent_block in parent_template.' + 'blocks.%s():' % dict_item_iter) + self.indent() + self.writeline('context.blocks.setdefault(name, []).' + 'append(parent_block)') + self.outdent() + + # if this extends statement was in the root level we can take + # advantage of that information and simplify the generated code + # in the top level from this point onwards + if frame.rootlevel: + self.has_known_extends = True + + # and now we have one more + self.extends_so_far += 1 + + def visit_Include(self, node, frame): + """Handles includes.""" + if node.ignore_missing: + self.writeline('try:') + self.indent() + + func_name = 'get_or_select_template' + if isinstance(node.template, nodes.Const): + if isinstance(node.template.value, string_types): + func_name = 'get_template' + elif isinstance(node.template.value, (tuple, list)): + func_name = 'select_template' + elif isinstance(node.template, (nodes.Tuple, nodes.List)): + func_name = 'select_template' + + self.writeline('template = environment.%s(' % func_name, node) + self.visit(node.template, frame) + self.write(', %r)' % self.name) + if node.ignore_missing: + self.outdent() + self.writeline('except TemplateNotFound:') + self.indent() + self.writeline('pass') + self.outdent() + self.writeline('else:') + self.indent() + + skip_event_yield = False + if node.with_context: + loop = self.environment.is_async and 'async for' or 'for' + self.writeline('%s event in template.root_render_func(' + 'template.new_context(context.get_all(), True, ' + '%s)):' % (loop, self.dump_local_context(frame))) + elif self.environment.is_async: + self.writeline('for event in (await ' + 'template._get_default_module_async())' + '._body_stream:') + else: + if supports_yield_from: + self.writeline('yield from template._get_default_module()' + '._body_stream') + skip_event_yield = True + else: + self.writeline('for event in template._get_default_module()' + '._body_stream:') + + if not skip_event_yield: + self.indent() + self.simple_write('event', frame) + self.outdent() + + if node.ignore_missing: + self.outdent() + + def visit_Import(self, node, frame): + """Visit regular imports.""" + self.writeline('%s = ' % frame.symbols.ref(node.target), node) + if frame.toplevel: + self.write('context.vars[%r] = ' % node.target) + if self.environment.is_async: + self.write('await ') + self.write('environment.get_template(') + self.visit(node.template, frame) + self.write(', %r).' % self.name) + if node.with_context: + self.write('make_module%s(context.get_all(), True, %s)' + % (self.environment.is_async and '_async' or '', + self.dump_local_context(frame))) + elif self.environment.is_async: + self.write('_get_default_module_async()') + else: + self.write('_get_default_module()') + if frame.toplevel and not node.target.startswith('_'): + self.writeline('context.exported_vars.discard(%r)' % node.target) + + def visit_FromImport(self, node, frame): + """Visit named imports.""" + self.newline(node) + self.write('included_template = %senvironment.get_template(' + % (self.environment.is_async and 'await ' or '')) + self.visit(node.template, frame) + self.write(', %r).' % self.name) + if node.with_context: + self.write('make_module%s(context.get_all(), True, %s)' + % (self.environment.is_async and '_async' or '', + self.dump_local_context(frame))) + elif self.environment.is_async: + self.write('_get_default_module_async()') + else: + self.write('_get_default_module()') + + var_names = [] + discarded_names = [] + for name in node.names: + if isinstance(name, tuple): + name, alias = name + else: + alias = name + self.writeline('%s = getattr(included_template, ' + '%r, missing)' % (frame.symbols.ref(alias), name)) + self.writeline('if %s is missing:' % frame.symbols.ref(alias)) + self.indent() + self.writeline('%s = undefined(%r %% ' + 'included_template.__name__, ' + 'name=%r)' % + (frame.symbols.ref(alias), + 'the template %%r (imported on %s) does ' + 'not export the requested name %s' % ( + self.position(node), + repr(name) + ), name)) + self.outdent() + if frame.toplevel: + var_names.append(alias) + if not alias.startswith('_'): + discarded_names.append(alias) + + if var_names: + if len(var_names) == 1: + name = var_names[0] + self.writeline('context.vars[%r] = %s' % + (name, frame.symbols.ref(name))) + else: + self.writeline('context.vars.update({%s})' % ', '.join( + '%r: %s' % (name, frame.symbols.ref(name)) for name in var_names + )) + if discarded_names: + if len(discarded_names) == 1: + self.writeline('context.exported_vars.discard(%r)' % + discarded_names[0]) + else: + self.writeline('context.exported_vars.difference_' + 'update((%s))' % ', '.join(imap(repr, discarded_names))) + + def visit_For(self, node, frame): + loop_frame = frame.inner() + test_frame = frame.inner() + else_frame = frame.inner() + + # try to figure out if we have an extended loop. An extended loop + # is necessary if the loop is in recursive mode if the special loop + # variable is accessed in the body. + extended_loop = node.recursive or 'loop' in \ + find_undeclared(node.iter_child_nodes( + only=('body',)), ('loop',)) + + loop_ref = None + if extended_loop: + loop_ref = loop_frame.symbols.declare_parameter('loop') + + loop_frame.symbols.analyze_node(node, for_branch='body') + if node.else_: + else_frame.symbols.analyze_node(node, for_branch='else') + + if node.test: + loop_filter_func = self.temporary_identifier() + test_frame.symbols.analyze_node(node, for_branch='test') + self.writeline('%s(fiter):' % self.func(loop_filter_func), node.test) + self.indent() + self.enter_frame(test_frame) + self.writeline(self.environment.is_async and 'async for ' or 'for ') + self.visit(node.target, loop_frame) + self.write(' in ') + self.write(self.environment.is_async and 'auto_aiter(fiter)' or 'fiter') + self.write(':') + self.indent() + self.writeline('if ', node.test) + self.visit(node.test, test_frame) + self.write(':') + self.indent() + self.writeline('yield ') + self.visit(node.target, loop_frame) + self.outdent(3) + self.leave_frame(test_frame, with_python_scope=True) + + # if we don't have an recursive loop we have to find the shadowed + # variables at that point. Because loops can be nested but the loop + # variable is a special one we have to enforce aliasing for it. + if node.recursive: + self.writeline('%s(reciter, loop_render_func, depth=0):' % + self.func('loop'), node) + self.indent() + self.buffer(loop_frame) + + # Use the same buffer for the else frame + else_frame.buffer = loop_frame.buffer + + # make sure the loop variable is a special one and raise a template + # assertion error if a loop tries to write to loop + if extended_loop: + self.writeline('%s = missing' % loop_ref) + + for name in node.find_all(nodes.Name): + if name.ctx == 'store' and name.name == 'loop': + self.fail('Can\'t assign to special loop variable ' + 'in for-loop target', name.lineno) + + if node.else_: + iteration_indicator = self.temporary_identifier() + self.writeline('%s = 1' % iteration_indicator) + + self.writeline(self.environment.is_async and 'async for ' or 'for ', node) + self.visit(node.target, loop_frame) + if extended_loop: + if self.environment.is_async: + self.write(', %s in await make_async_loop_context(' % loop_ref) + else: + self.write(', %s in LoopContext(' % loop_ref) + else: + self.write(' in ') + + if node.test: + self.write('%s(' % loop_filter_func) + if node.recursive: + self.write('reciter') + else: + if self.environment.is_async and not extended_loop: + self.write('auto_aiter(') + self.visit(node.iter, frame) + if self.environment.is_async and not extended_loop: + self.write(')') + if node.test: + self.write(')') + + if node.recursive: + self.write(', undefined, loop_render_func, depth):') + else: + self.write(extended_loop and ', undefined):' or ':') + + self.indent() + self.enter_frame(loop_frame) + + self.blockvisit(node.body, loop_frame) + if node.else_: + self.writeline('%s = 0' % iteration_indicator) + self.outdent() + self.leave_frame(loop_frame, with_python_scope=node.recursive + and not node.else_) + + if node.else_: + self.writeline('if %s:' % iteration_indicator) + self.indent() + self.enter_frame(else_frame) + self.blockvisit(node.else_, else_frame) + self.leave_frame(else_frame) + self.outdent() + + # if the node was recursive we have to return the buffer contents + # and start the iteration code + if node.recursive: + self.return_buffer_contents(loop_frame) + self.outdent() + self.start_write(frame, node) + if self.environment.is_async: + self.write('await ') + self.write('loop(') + if self.environment.is_async: + self.write('auto_aiter(') + self.visit(node.iter, frame) + if self.environment.is_async: + self.write(')') + self.write(', loop)') + self.end_write(frame) + + def visit_If(self, node, frame): + if_frame = frame.soft() + self.writeline('if ', node) + self.visit(node.test, if_frame) + self.write(':') + self.indent() + self.blockvisit(node.body, if_frame) + self.outdent() + for elif_ in node.elif_: + self.writeline('elif ', elif_) + self.visit(elif_.test, if_frame) + self.write(':') + self.indent() + self.blockvisit(elif_.body, if_frame) + self.outdent() + if node.else_: + self.writeline('else:') + self.indent() + self.blockvisit(node.else_, if_frame) + self.outdent() + + def visit_Macro(self, node, frame): + macro_frame, macro_ref = self.macro_body(node, frame) + self.newline() + if frame.toplevel: + if not node.name.startswith('_'): + self.write('context.exported_vars.add(%r)' % node.name) + ref = frame.symbols.ref(node.name) + self.writeline('context.vars[%r] = ' % node.name) + self.write('%s = ' % frame.symbols.ref(node.name)) + self.macro_def(macro_ref, macro_frame) + + def visit_CallBlock(self, node, frame): + call_frame, macro_ref = self.macro_body(node, frame) + self.writeline('caller = ') + self.macro_def(macro_ref, call_frame) + self.start_write(frame, node) + self.visit_Call(node.call, frame, forward_caller=True) + self.end_write(frame) + + def visit_FilterBlock(self, node, frame): + filter_frame = frame.inner() + filter_frame.symbols.analyze_node(node) + self.enter_frame(filter_frame) + self.buffer(filter_frame) + self.blockvisit(node.body, filter_frame) + self.start_write(frame, node) + self.visit_Filter(node.filter, filter_frame) + self.end_write(frame) + self.leave_frame(filter_frame) + + def visit_With(self, node, frame): + with_frame = frame.inner() + with_frame.symbols.analyze_node(node) + self.enter_frame(with_frame) + for idx, (target, expr) in enumerate(izip(node.targets, node.values)): + self.newline() + self.visit(target, with_frame) + self.write(' = ') + self.visit(expr, frame) + self.blockvisit(node.body, with_frame) + self.leave_frame(with_frame) + + def visit_ExprStmt(self, node, frame): + self.newline(node) + self.visit(node.node, frame) + + def visit_Output(self, node, frame): + # if we have a known extends statement, we don't output anything + # if we are in a require_output_check section + if self.has_known_extends and frame.require_output_check: + return + + allow_constant_finalize = True + if self.environment.finalize: + func = self.environment.finalize + if getattr(func, 'contextfunction', False) or \ + getattr(func, 'evalcontextfunction', False): + allow_constant_finalize = False + elif getattr(func, 'environmentfunction', False): + finalize = lambda x: text_type( + self.environment.finalize(self.environment, x)) + else: + finalize = lambda x: text_type(self.environment.finalize(x)) + else: + finalize = text_type + + # if we are inside a frame that requires output checking, we do so + outdent_later = False + if frame.require_output_check: + self.writeline('if parent_template is None:') + self.indent() + outdent_later = True + + # try to evaluate as many chunks as possible into a static + # string at compile time. + body = [] + for child in node.nodes: + try: + if not allow_constant_finalize: + raise nodes.Impossible() + const = child.as_const(frame.eval_ctx) + except nodes.Impossible: + body.append(child) + continue + # the frame can't be volatile here, becaus otherwise the + # as_const() function would raise an Impossible exception + # at that point. + try: + if frame.eval_ctx.autoescape: + if hasattr(const, '__html__'): + const = const.__html__() + else: + const = escape(const) + const = finalize(const) + except Exception: + # if something goes wrong here we evaluate the node + # at runtime for easier debugging + body.append(child) + continue + if body and isinstance(body[-1], list): + body[-1].append(const) + else: + body.append([const]) + + # if we have less than 3 nodes or a buffer we yield or extend/append + if len(body) < 3 or frame.buffer is not None: + if frame.buffer is not None: + # for one item we append, for more we extend + if len(body) == 1: + self.writeline('%s.append(' % frame.buffer) + else: + self.writeline('%s.extend((' % frame.buffer) + self.indent() + for item in body: + if isinstance(item, list): + val = repr(concat(item)) + if frame.buffer is None: + self.writeline('yield ' + val) + else: + self.writeline(val + ',') + else: + if frame.buffer is None: + self.writeline('yield ', item) + else: + self.newline(item) + close = 1 + if frame.eval_ctx.volatile: + self.write('(escape if context.eval_ctx.autoescape' + ' else to_string)(') + elif frame.eval_ctx.autoescape: + self.write('escape(') + else: + self.write('to_string(') + if self.environment.finalize is not None: + self.write('environment.finalize(') + if getattr(self.environment.finalize, + "contextfunction", False): + self.write('context, ') + close += 1 + self.visit(item, frame) + self.write(')' * close) + if frame.buffer is not None: + self.write(',') + if frame.buffer is not None: + # close the open parentheses + self.outdent() + self.writeline(len(body) == 1 and ')' or '))') + + # otherwise we create a format string as this is faster in that case + else: + format = [] + arguments = [] + for item in body: + if isinstance(item, list): + format.append(concat(item).replace('%', '%%')) + else: + format.append('%s') + arguments.append(item) + self.writeline('yield ') + self.write(repr(concat(format)) + ' % (') + self.indent() + for argument in arguments: + self.newline(argument) + close = 0 + if frame.eval_ctx.volatile: + self.write('(escape if context.eval_ctx.autoescape else' + ' to_string)(') + close += 1 + elif frame.eval_ctx.autoescape: + self.write('escape(') + close += 1 + if self.environment.finalize is not None: + self.write('environment.finalize(') + if getattr(self.environment.finalize, + 'contextfunction', False): + self.write('context, ') + elif getattr(self.environment.finalize, + 'evalcontextfunction', False): + self.write('context.eval_ctx, ') + elif getattr(self.environment.finalize, + 'environmentfunction', False): + self.write('environment, ') + close += 1 + self.visit(argument, frame) + self.write(')' * close + ', ') + self.outdent() + self.writeline(')') + + if outdent_later: + self.outdent() + + def visit_Assign(self, node, frame): + self.push_assign_tracking() + self.newline(node) + self.visit(node.target, frame) + self.write(' = ') + self.visit(node.node, frame) + self.pop_assign_tracking(frame) + + def visit_AssignBlock(self, node, frame): + self.push_assign_tracking() + block_frame = frame.inner() + # This is a special case. Since a set block always captures we + # will disable output checks. This way one can use set blocks + # toplevel even in extended templates. + block_frame.require_output_check = False + block_frame.symbols.analyze_node(node) + self.enter_frame(block_frame) + self.buffer(block_frame) + self.blockvisit(node.body, block_frame) + self.newline(node) + self.visit(node.target, frame) + self.write(' = (Markup if context.eval_ctx.autoescape ' + 'else identity)(') + if node.filter is not None: + self.visit_Filter(node.filter, block_frame) + else: + self.write('concat(%s)' % block_frame.buffer) + self.write(')') + self.pop_assign_tracking(frame) + self.leave_frame(block_frame) + + # -- Expression Visitors + + def visit_Name(self, node, frame): + if node.ctx == 'store' and frame.toplevel: + if self._assign_stack: + self._assign_stack[-1].add(node.name) + ref = frame.symbols.ref(node.name) + + # If we are looking up a variable we might have to deal with the + # case where it's undefined. We can skip that case if the load + # instruction indicates a parameter which are always defined. + if node.ctx == 'load': + load = frame.symbols.find_load(ref) + if not (load is not None and load[0] == VAR_LOAD_PARAMETER and \ + not self.parameter_is_undeclared(ref)): + self.write('(undefined(name=%r) if %s is missing else %s)' % + (node.name, ref, ref)) + return + + self.write(ref) + + def visit_NSRef(self, node, frame): + # NSRefs can only be used to store values; since they use the normal + # `foo.bar` notation they will be parsed as a normal attribute access + # when used anywhere but in a `set` context + ref = frame.symbols.ref(node.name) + self.writeline('if not isinstance(%s, Namespace):' % ref) + self.indent() + self.writeline('raise TemplateRuntimeError(%r)' % + 'cannot assign attribute on non-namespace object') + self.outdent() + self.writeline('%s[%r]' % (ref, node.attr)) + + def visit_Const(self, node, frame): + val = node.as_const(frame.eval_ctx) + if isinstance(val, float): + self.write(str(val)) + else: + self.write(repr(val)) + + def visit_TemplateData(self, node, frame): + try: + self.write(repr(node.as_const(frame.eval_ctx))) + except nodes.Impossible: + self.write('(Markup if context.eval_ctx.autoescape else identity)(%r)' + % node.data) + + def visit_Tuple(self, node, frame): + self.write('(') + idx = -1 + for idx, item in enumerate(node.items): + if idx: + self.write(', ') + self.visit(item, frame) + self.write(idx == 0 and ',)' or ')') + + def visit_List(self, node, frame): + self.write('[') + for idx, item in enumerate(node.items): + if idx: + self.write(', ') + self.visit(item, frame) + self.write(']') + + def visit_Dict(self, node, frame): + self.write('{') + for idx, item in enumerate(node.items): + if idx: + self.write(', ') + self.visit(item.key, frame) + self.write(': ') + self.visit(item.value, frame) + self.write('}') + + def binop(operator, interceptable=True): + @optimizeconst + def visitor(self, node, frame): + if self.environment.sandboxed and \ + operator in self.environment.intercepted_binops: + self.write('environment.call_binop(context, %r, ' % operator) + self.visit(node.left, frame) + self.write(', ') + self.visit(node.right, frame) + else: + self.write('(') + self.visit(node.left, frame) + self.write(' %s ' % operator) + self.visit(node.right, frame) + self.write(')') + return visitor + + def uaop(operator, interceptable=True): + @optimizeconst + def visitor(self, node, frame): + if self.environment.sandboxed and \ + operator in self.environment.intercepted_unops: + self.write('environment.call_unop(context, %r, ' % operator) + self.visit(node.node, frame) + else: + self.write('(' + operator) + self.visit(node.node, frame) + self.write(')') + return visitor + + visit_Add = binop('+') + visit_Sub = binop('-') + visit_Mul = binop('*') + visit_Div = binop('/') + visit_FloorDiv = binop('//') + visit_Pow = binop('**') + visit_Mod = binop('%') + visit_And = binop('and', interceptable=False) + visit_Or = binop('or', interceptable=False) + visit_Pos = uaop('+') + visit_Neg = uaop('-') + visit_Not = uaop('not ', interceptable=False) + del binop, uaop + + @optimizeconst + def visit_Concat(self, node, frame): + if frame.eval_ctx.volatile: + func_name = '(context.eval_ctx.volatile and' \ + ' markup_join or unicode_join)' + elif frame.eval_ctx.autoescape: + func_name = 'markup_join' + else: + func_name = 'unicode_join' + self.write('%s((' % func_name) + for arg in node.nodes: + self.visit(arg, frame) + self.write(', ') + self.write('))') + + @optimizeconst + def visit_Compare(self, node, frame): + self.visit(node.expr, frame) + for op in node.ops: + self.visit(op, frame) + + def visit_Operand(self, node, frame): + self.write(' %s ' % operators[node.op]) + self.visit(node.expr, frame) + + @optimizeconst + def visit_Getattr(self, node, frame): + self.write('environment.getattr(') + self.visit(node.node, frame) + self.write(', %r)' % node.attr) + + @optimizeconst + def visit_Getitem(self, node, frame): + # slices bypass the environment getitem method. + if isinstance(node.arg, nodes.Slice): + self.visit(node.node, frame) + self.write('[') + self.visit(node.arg, frame) + self.write(']') + else: + self.write('environment.getitem(') + self.visit(node.node, frame) + self.write(', ') + self.visit(node.arg, frame) + self.write(')') + + def visit_Slice(self, node, frame): + if node.start is not None: + self.visit(node.start, frame) + self.write(':') + if node.stop is not None: + self.visit(node.stop, frame) + if node.step is not None: + self.write(':') + self.visit(node.step, frame) + + @optimizeconst + def visit_Filter(self, node, frame): + if self.environment.is_async: + self.write('await auto_await(') + self.write(self.filters[node.name] + '(') + func = self.environment.filters.get(node.name) + if func is None: + self.fail('no filter named %r' % node.name, node.lineno) + if getattr(func, 'contextfilter', False): + self.write('context, ') + elif getattr(func, 'evalcontextfilter', False): + self.write('context.eval_ctx, ') + elif getattr(func, 'environmentfilter', False): + self.write('environment, ') + + # if the filter node is None we are inside a filter block + # and want to write to the current buffer + if node.node is not None: + self.visit(node.node, frame) + elif frame.eval_ctx.volatile: + self.write('(context.eval_ctx.autoescape and' + ' Markup(concat(%s)) or concat(%s))' % + (frame.buffer, frame.buffer)) + elif frame.eval_ctx.autoescape: + self.write('Markup(concat(%s))' % frame.buffer) + else: + self.write('concat(%s)' % frame.buffer) + self.signature(node, frame) + self.write(')') + if self.environment.is_async: + self.write(')') + + @optimizeconst + def visit_Test(self, node, frame): + self.write(self.tests[node.name] + '(') + if node.name not in self.environment.tests: + self.fail('no test named %r' % node.name, node.lineno) + self.visit(node.node, frame) + self.signature(node, frame) + self.write(')') + + @optimizeconst + def visit_CondExpr(self, node, frame): + def write_expr2(): + if node.expr2 is not None: + return self.visit(node.expr2, frame) + self.write('undefined(%r)' % ('the inline if-' + 'expression on %s evaluated to false and ' + 'no else section was defined.' % self.position(node))) + + self.write('(') + self.visit(node.expr1, frame) + self.write(' if ') + self.visit(node.test, frame) + self.write(' else ') + write_expr2() + self.write(')') + + @optimizeconst + def visit_Call(self, node, frame, forward_caller=False): + if self.environment.is_async: + self.write('await auto_await(') + if self.environment.sandboxed: + self.write('environment.call(context, ') + else: + self.write('context.call(') + self.visit(node.node, frame) + extra_kwargs = forward_caller and {'caller': 'caller'} or None + self.signature(node, frame, extra_kwargs) + self.write(')') + if self.environment.is_async: + self.write(')') + + def visit_Keyword(self, node, frame): + self.write(node.key + '=') + self.visit(node.value, frame) + + # -- Unused nodes for extensions + + def visit_MarkSafe(self, node, frame): + self.write('Markup(') + self.visit(node.expr, frame) + self.write(')') + + def visit_MarkSafeIfAutoescape(self, node, frame): + self.write('(context.eval_ctx.autoescape and Markup or identity)(') + self.visit(node.expr, frame) + self.write(')') + + def visit_EnvironmentAttribute(self, node, frame): + self.write('environment.' + node.name) + + def visit_ExtensionAttribute(self, node, frame): + self.write('environment.extensions[%r].%s' % (node.identifier, node.name)) + + def visit_ImportedName(self, node, frame): + self.write(self.import_aliases[node.importname]) + + def visit_InternalName(self, node, frame): + self.write(node.name) + + def visit_ContextReference(self, node, frame): + self.write('context') + + def visit_Continue(self, node, frame): + self.writeline('continue', node) + + def visit_Break(self, node, frame): + self.writeline('break', node) + + def visit_Scope(self, node, frame): + scope_frame = frame.inner() + scope_frame.symbols.analyze_node(node) + self.enter_frame(scope_frame) + self.blockvisit(node.body, scope_frame) + self.leave_frame(scope_frame) + + def visit_OverlayScope(self, node, frame): + ctx = self.temporary_identifier() + self.writeline('%s = %s' % (ctx, self.derive_context(frame))) + self.writeline('%s.vars = ' % ctx) + self.visit(node.context, frame) + self.push_context_reference(ctx) + + scope_frame = frame.inner(isolated=True) + scope_frame.symbols.analyze_node(node) + self.enter_frame(scope_frame) + self.blockvisit(node.body, scope_frame) + self.leave_frame(scope_frame) + self.pop_context_reference() + + def visit_EvalContextModifier(self, node, frame): + for keyword in node.options: + self.writeline('context.eval_ctx.%s = ' % keyword.key) + self.visit(keyword.value, frame) + try: + val = keyword.value.as_const(frame.eval_ctx) + except nodes.Impossible: + frame.eval_ctx.volatile = True + else: + setattr(frame.eval_ctx, keyword.key, val) + + def visit_ScopedEvalContextModifier(self, node, frame): + old_ctx_name = self.temporary_identifier() + saved_ctx = frame.eval_ctx.save() + self.writeline('%s = context.eval_ctx.save()' % old_ctx_name) + self.visit_EvalContextModifier(node, frame) + for child in node.body: + self.visit(child, frame) + frame.eval_ctx.revert(saved_ctx) + self.writeline('context.eval_ctx.revert(%s)' % old_ctx_name) -- cgit v1.2.3