| # -*- coding: utf-8 -*- |
| """ |
| jinja2.compiler |
| ~~~~~~~~~~~~~~~ |
| |
| Compiles nodes into python code. |
| |
| :copyright: Copyright 2008 by Armin Ronacher. |
| :license: GNU GPL. |
| """ |
| from copy import copy |
| from random import randrange |
| from keyword import iskeyword |
| from cStringIO import StringIO |
| from itertools import chain |
| from jinja2 import nodes |
| from jinja2.visitor import NodeVisitor, NodeTransformer |
| from jinja2.exceptions import TemplateAssertionError |
| from jinja2.runtime import StaticLoopContext, concat |
| from jinja2.utils import Markup |
| |
| |
| operators = { |
| 'eq': '==', |
| 'ne': '!=', |
| 'gt': '>', |
| 'gteq': '>=', |
| 'lt': '<', |
| 'lteq': '<=', |
| 'in': 'in', |
| 'notin': 'not in' |
| } |
| |
| |
| try: |
| exec '(0 if 0 else 0)' |
| except SyntaxError: |
| have_condexpr = False |
| else: |
| have_condexpr = True |
| |
| |
| def generate(node, environment, name, filename, stream=None): |
| """Generate the python source for a node tree.""" |
| generator = CodeGenerator(environment, name, filename, stream) |
| 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 isinstance(value, (bool, int, long, float, complex, basestring, |
| xrange, StaticLoopContext, Markup)): |
| return True |
| if isinstance(value, (tuple, list, set, frozenset)): |
| for item in value: |
| if not has_safe_repr(item): |
| return False |
| return True |
| elif isinstance(value, dict): |
| for key, value in value.iteritems(): |
| if not has_safe_repr(key): |
| return False |
| if not has_safe_repr(value): |
| return False |
| return True |
| return False |
| |
| |
| class Identifiers(object): |
| """Tracks the status of identifiers in frames.""" |
| |
| def __init__(self): |
| # variables that are known to be declared (probably from outer |
| # frames or because they are special for the frame) |
| self.declared = set() |
| |
| # undeclared variables from outer scopes |
| self.outer_undeclared = set() |
| |
| # names that are accessed without being explicitly declared by |
| # this one or any of the outer scopes. Names can appear both in |
| # declared and undeclared. |
| self.undeclared = set() |
| |
| # names that are declared locally |
| self.declared_locally = set() |
| |
| # names that are declared by parameters |
| self.declared_parameter = set() |
| |
| # filters/tests that are referenced |
| self.filters = set() |
| self.tests = set() |
| |
| def add_special(self, name): |
| """Register a special name like `loop`.""" |
| self.undeclared.discard(name) |
| self.declared.add(name) |
| |
| def is_declared(self, name, local_only=False): |
| """Check if a name is declared in this or an outer scope.""" |
| if name in self.declared_locally or name in self.declared_parameter: |
| return True |
| if local_only: |
| return False |
| return name in self.declared |
| |
| def find_shadowed(self): |
| """Find all the shadowed names.""" |
| return (self.declared | self.outer_undeclared) & \ |
| (self.declared_locally | self.declared_parameter) |
| |
| |
| class Frame(object): |
| """Holds compile time information for us.""" |
| |
| def __init__(self, parent=None): |
| self.identifiers = Identifiers() |
| |
| # 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 |
| |
| # 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 |
| |
| # if a frame has name_overrides, all read access to a name in this |
| # dict is redirected to a string expression. |
| self.name_overrides = {} |
| |
| # 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.identifiers.declared.update( |
| parent.identifiers.declared | |
| parent.identifiers.declared_locally | |
| parent.identifiers.declared_parameter |
| ) |
| self.identifiers.outer_undeclared.update( |
| parent.identifiers.undeclared - |
| self.identifiers.declared |
| ) |
| self.buffer = parent.buffer |
| self.name_overrides = parent.name_overrides.copy() |
| |
| def copy(self): |
| """Create a copy of the current one.""" |
| rv = copy(self) |
| rv.identifiers = copy(self.identifiers) |
| rv.name_overrides = self.name_overrides.copy() |
| return rv |
| |
| def inspect(self, nodes, with_depenencies=False, hard_scope=False): |
| """Walk the node and check for identifiers. If the scope is hard (eg: |
| enforce on a python level) overrides from outer scopes are tracked |
| differently. |
| |
| Per default filters and tests (dependencies) are not tracked. That's |
| the case because filters and tests are absolutely immutable and so we |
| can savely use them in closures too. The `Template` and `Block` |
| visitor visits the frame with dependencies to collect them. |
| """ |
| visitor = FrameIdentifierVisitor(self.identifiers, hard_scope) |
| for node in nodes: |
| visitor.visit(node, True, with_depenencies) |
| |
| def inner(self): |
| """Return an inner frame.""" |
| return Frame(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. |
| """ |
| rv = copy(self) |
| rv.rootlevel = False |
| return rv |
| |
| |
| class FrameIdentifierVisitor(NodeVisitor): |
| """A visitor for `Frame.inspect`.""" |
| |
| def __init__(self, identifiers, hard_scope): |
| self.identifiers = identifiers |
| self.hard_scope = hard_scope |
| |
| def visit_Name(self, node, visit_ident, visit_deps): |
| """All assignments to names go through this function.""" |
| if visit_ident: |
| if node.ctx in ('store', 'param'): |
| self.identifiers.declared_locally.add(node.name) |
| elif node.ctx == 'load' and not \ |
| self.identifiers.is_declared(node.name, self.hard_scope): |
| self.identifiers.undeclared.add(node.name) |
| |
| def visit_Filter(self, node, visit_ident, visit_deps): |
| if visit_deps: |
| self.generic_visit(node, visit_ident, True) |
| self.identifiers.filters.add(node.name) |
| |
| def visit_Test(self, node, visit_ident, visit_deps): |
| if visit_deps: |
| self.generic_visit(node, visit_ident, True) |
| self.identifiers.tests.add(node.name) |
| |
| def visit_Macro(self, node, visit_ident, visit_deps): |
| if visit_ident: |
| self.identifiers.declared_locally.add(node.name) |
| |
| def visit_Import(self, node, visit_ident, visit_deps): |
| if visit_ident: |
| self.generic_visit(node, True, visit_deps) |
| self.identifiers.declared_locally.add(node.target) |
| |
| def visit_FromImport(self, node, visit_ident, visit_deps): |
| if visit_ident: |
| self.generic_visit(node, True, visit_deps) |
| for name in node.names: |
| if isinstance(name, tuple): |
| self.identifiers.declared_locally.add(name[1]) |
| else: |
| self.identifiers.declared_locally.add(name) |
| |
| def visit_Assign(self, node, visit_ident, visit_deps): |
| """Visit assignments in the correct order.""" |
| self.visit(node.node, visit_ident, visit_deps) |
| self.visit(node.target, visit_ident, visit_deps) |
| |
| def visit_For(self, node, visit_ident, visit_deps): |
| """Visiting stops at for blocks. However the block sequence |
| is visited as part of the outer scope. |
| """ |
| if visit_ident: |
| self.visit(node.iter, True, visit_deps) |
| if visit_deps: |
| for child in node.iter_child_nodes(exclude=('iter',)): |
| self.visit(child, False, True) |
| |
| def ident_stop(self, node, visit_ident, visit_deps): |
| if visit_deps: |
| self.generic_visit(node, False, True) |
| visit_CallBlock = visit_FilterBlock = ident_stop |
| visit_Block = lambda s, n, a, b: None |
| |
| |
| 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): |
| if stream is None: |
| stream = StringIO() |
| self.environment = environment |
| self.name = name |
| self.filename = filename |
| self.stream = stream |
| |
| # 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 |
| |
| # 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 |
| |
| def temporary_identifier(self): |
| """Get a new unique identifier.""" |
| self._last_identifier += 1 |
| return 't%d' % self._last_identifier |
| |
| def indent(self): |
| """Indent by one.""" |
| self._indentation += 1 |
| |
| def outdent(self, step=1): |
| """Outdent by step.""" |
| self._indentation -= step |
| |
| def blockvisit(self, nodes, frame, indent=True, force_generator=True): |
| """Visit a list of nodes as block in a frame. Per default the |
| code is indented, but this can be disabled by setting the indent |
| parameter to False. If the current frame is no buffer a dummy |
| ``if 0: yield None`` is written automatically unless the |
| force_generator parameter is set to False. |
| """ |
| if indent: |
| self.indent() |
| if frame.buffer is None and force_generator: |
| self.writeline('if 0: yield None') |
| try: |
| for node in nodes: |
| self.visit(node, frame) |
| except CompilerExit: |
| pass |
| if indent: |
| self.outdent() |
| |
| 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, have_comma=True, extra_kwargs=None): |
| """Writes a function call to the stream for the current node. |
| Per default it will write a leading comma but this can be |
| disabled by setting have_comma to False. 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. |
| """ |
| have_comma = have_comma and [True] or [] |
| def touch_comma(): |
| if have_comma: |
| self.write(', ') |
| else: |
| have_comma.append(True) |
| |
| # 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 iskeyword(kwarg): |
| kwarg_workaround = True |
| break |
| |
| for arg in node.args: |
| touch_comma() |
| self.visit(arg, frame) |
| |
| if not kwarg_workaround: |
| for kwarg in node.kwargs: |
| touch_comma() |
| self.visit(kwarg, frame) |
| if extra_kwargs is not None: |
| for key, value in extra_kwargs.iteritems(): |
| touch_comma() |
| self.write('%s=%s' % (key, value)) |
| if node.dyn_args: |
| touch_comma() |
| self.write('*') |
| self.visit(node.dyn_args, frame) |
| |
| if kwarg_workaround: |
| touch_comma() |
| 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 extra_kwargs.iteritems(): |
| touch_comma() |
| 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: |
| touch_comma() |
| self.write('**') |
| self.visit(node.dyn_kwargs, frame) |
| |
| def pull_locals(self, frame, indent=True): |
| """Pull all the references identifiers into the local scope. |
| This affects regular names, filters and tests. If indent is |
| set to False, no automatic indentation will take place. |
| """ |
| if indent: |
| self.indent() |
| for name in frame.identifiers.undeclared: |
| self.writeline('l_%s = context[%r]' % (name, name)) |
| for name in frame.identifiers.filters: |
| self.writeline('f_%s = environment.filters[%r]' % (name, name)) |
| for name in frame.identifiers.tests: |
| self.writeline('t_%s = environment.tests[%r]' % (name, name)) |
| if indent: |
| self.outdent() |
| |
| def collect_shadowed(self, frame): |
| """This function returns all the shadowed variables in a dict |
| in the form name: alias and will write the required assignments |
| into the current scope. No indentation takes place. |
| """ |
| # make sure we "backup" overridden, local identifiers |
| # TODO: we should probably optimize this and check if the |
| # identifier is in use afterwards. |
| aliases = {} |
| for name in frame.identifiers.find_shadowed(): |
| aliases[name] = ident = self.temporary_identifier() |
| self.writeline('%s = l_%s' % (ident, name)) |
| return aliases |
| |
| def function_scoping(self, node, frame): |
| """In Jinja a few statements require the help of anonymous |
| functions. Those are currently macros and call blocks and in |
| the future also recursive loops. As there is currently |
| technical limitation that doesn't allow reading and writing a |
| variable in a scope where the initial value is coming from an |
| outer scope, this function tries to fall back with a common |
| error message. Additionally the frame passed is modified so |
| that the argumetns are collected and callers are looked up. |
| |
| This will return the modified frame. |
| """ |
| func_frame = frame.inner() |
| func_frame.inspect(node.iter_child_nodes(), hard_scope=True) |
| |
| # variables that are undeclared (accessed before declaration) and |
| # declared locally *and* part of an outside scope raise a template |
| # assertion error. Reason: we can't generate reasonable code from |
| # it without aliasing all the variables. XXX: alias them ^^ |
| overriden_closure_vars = ( |
| func_frame.identifiers.undeclared & |
| func_frame.identifiers.declared & |
| (func_frame.identifiers.declared_locally | |
| func_frame.identifiers.declared_parameter) |
| ) |
| if overriden_closure_vars: |
| vars = ', '.join(sorted(overriden_closure_vars)) |
| raise TemplateAssertionError('It\'s not possible to set and ' |
| 'access variables derived from ' |
| 'an outer scope! (affects: %s' % |
| vars, node.lineno, self.name) |
| |
| # remove variables from a closure from the frame's undeclared |
| # identifiers. |
| func_frame.identifiers.undeclared -= ( |
| func_frame.identifiers.undeclared & |
| func_frame.identifiers.declared |
| ) |
| |
| func_frame.accesses_kwargs = False |
| func_frame.accesses_varargs = False |
| func_frame.accesses_caller = False |
| func_frame.arguments = args = ['l_' + x.name for x in node.args] |
| |
| if 'caller' in func_frame.identifiers.undeclared: |
| func_frame.accesses_caller = True |
| func_frame.identifiers.add_special('caller') |
| args.append('l_caller') |
| if 'kwargs' in func_frame.identifiers.undeclared: |
| func_frame.accesses_kwargs = True |
| func_frame.identifiers.add_special('kwargs') |
| args.append('l_kwargs') |
| if 'varargs' in func_frame.identifiers.undeclared: |
| func_frame.accesses_varargs = True |
| func_frame.identifiers.add_special('varargs') |
| args.append('l_varargs') |
| return func_frame |
| |
| # -- Visitors |
| |
| def visit_Template(self, node, frame=None): |
| assert frame is None, 'no root frame allowed' |
| from jinja2.runtime import __all__ as exported |
| self.writeline('from jinja2.runtime import ' + ', '.join(exported)) |
| self.writeline('name = %r' % self.name) |
| |
| # 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: |
| raise TemplateAssertionError('block %r defined twice' % |
| block.name, block.lineno, |
| self.name) |
| self.blocks[block.name] = block |
| |
| # generate the root render function. |
| self.writeline('def root(context, environment=environment' |
| '):', extra=1) |
| if have_extends: |
| self.indent() |
| self.writeline('parent_template = None') |
| self.outdent() |
| |
| # process the root |
| frame = Frame() |
| frame.inspect(node.body, with_depenencies=True) |
| frame.toplevel = frame.rootlevel = True |
| self.indent() |
| self.pull_locals(frame, indent=False) |
| self.blockvisit(node.body, frame, indent=False) |
| 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() |
| self.writeline('for event in parent_template.' |
| 'root_render_func(context):') |
| self.indent() |
| self.writeline('yield event') |
| self.outdent(2 + (not self.has_known_extends)) |
| |
| # at this point we now have the blocks collected and can visit them too. |
| for name, block in self.blocks.iteritems(): |
| block_frame = Frame() |
| block_frame.inspect(block.body, with_depenencies=True) |
| block_frame.block = name |
| block_frame.identifiers.add_special('super') |
| block_frame.name_overrides['super'] = 'context.super(%r, ' \ |
| 'block_%s)' % (name, name) |
| self.writeline('def block_%s(context, environment=environment):' |
| % name, block, 1) |
| self.pull_locals(block_frame) |
| self.blockvisit(block.body, block_frame) |
| |
| 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 = 1 |
| 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 |
| self.writeline('for event in context.blocks[%r][-1](context):' % node.name) |
| self.indent() |
| if frame.buffer is None: |
| self.writeline('yield event') |
| else: |
| self.writeline('%s.append(event)' % frame.buffer) |
| self.outdent(level) |
| |
| def visit_Extends(self, node, frame): |
| """Calls the extender.""" |
| if not frame.toplevel: |
| raise TemplateAssertionError('cannot use extend from a non ' |
| 'top-level scope', node.lineno, |
| self.name) |
| |
| # 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() |
| self.outdent() |
| |
| self.writeline('parent_template = environment.get_template(', node, 1) |
| self.visit(node.template, frame) |
| self.write(', %r)' % self.name) |
| self.writeline('for name, parent_block in parent_template.' |
| 'blocks.iteritems():') |
| self.indent() |
| self.writeline('context.blocks.setdefault(name, []).' |
| 'insert(0, 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 |
| self.has_known_extends = True |
| |
| # and now we have one more |
| self.extends_so_far += 1 |
| |
| def visit_Include(self, node, frame): |
| """Handles includes.""" |
| self.writeline('included_template = environment.get_template(', node) |
| self.visit(node.template, frame) |
| self.write(', %r)' % self.name) |
| self.writeline('for event in included_template.root_render_func(' |
| 'included_template.new_context(context.get_root())):') |
| self.indent() |
| if frame.buffer is None: |
| self.writeline('yield event') |
| else: |
| self.writeline('%s.append(event)' % frame.buffer) |
| self.outdent() |
| |
| def visit_Import(self, node, frame): |
| """Visit regular imports.""" |
| self.writeline('l_%s = ' % node.target, node) |
| if frame.toplevel: |
| self.write('context.vars[%r] = ' % node.target) |
| self.write('environment.get_template(') |
| self.visit(node.template, frame) |
| self.write(', %r).include(context)' % self.name) |
| if frame.toplevel: |
| 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 = environment.get_template(') |
| self.visit(node.template, frame) |
| self.write(', %r).include(context)' % self.name) |
| for name in node.names: |
| if isinstance(name, tuple): |
| name, alias = name |
| else: |
| alias = name |
| self.writeline('l_%s = getattr(included_template, ' |
| '%r, missing)' % (alias, name)) |
| self.writeline('if l_%s is missing:' % alias) |
| self.indent() |
| self.writeline('l_%s = environment.undefined(%r %% ' |
| 'included_template.name)' % |
| (alias, 'the template %r does not export ' |
| 'the requested name ' + repr(name))) |
| self.outdent() |
| if frame.toplevel: |
| self.writeline('context.vars[%r] = l_%s' % (alias, alias)) |
| self.writeline('context.exported_vars.discard(%r)' % alias) |
| |
| def visit_For(self, node, frame): |
| loop_frame = frame.inner() |
| loop_frame.inspect(node.iter_child_nodes(exclude=('iter',))) |
| extended_loop = bool(node.else_) or \ |
| 'loop' in loop_frame.identifiers.undeclared |
| if extended_loop: |
| loop_frame.identifiers.add_special('loop') |
| |
| aliases = self.collect_shadowed(loop_frame) |
| self.pull_locals(loop_frame, indent=False) |
| if node.else_: |
| self.writeline('l_loop = None') |
| |
| self.newline(node) |
| self.writeline('for ') |
| self.visit(node.target, loop_frame) |
| self.write(extended_loop and ', l_loop in LoopContext(' or ' in ') |
| |
| # the expression pointing to the parent loop. We make the |
| # undefined a bit more debug friendly at the same time. |
| parent_loop = 'loop' in aliases and aliases['loop'] \ |
| or "environment.undefined(%r)" % "'loop' is undefined. " \ |
| 'the filter section of a loop as well as the ' \ |
| 'else block doesn\'t have access to the special ' \ |
| "'loop' variable of the current loop. Because " \ |
| 'there is no parent loop it\'s undefined.' |
| |
| # if we have an extened loop and a node test, we filter in the |
| # "outer frame". |
| if extended_loop and node.test is not None: |
| self.write('(') |
| self.visit(node.target, loop_frame) |
| self.write(' for ') |
| self.visit(node.target, loop_frame) |
| self.write(' in ') |
| self.visit(node.iter, loop_frame) |
| self.write(' if (') |
| test_frame = loop_frame.copy() |
| test_frame.name_overrides['loop'] = parent_loop |
| self.visit(node.test, test_frame) |
| self.write('))') |
| |
| else: |
| self.visit(node.iter, loop_frame) |
| |
| self.write(extended_loop and '):' or ':') |
| |
| # tests in not extended loops become a continue |
| if not extended_loop and node.test is not None: |
| self.indent() |
| self.writeline('if ') |
| self.visit(node.test) |
| self.write(':') |
| self.indent() |
| self.writeline('continue') |
| self.outdent(2) |
| |
| self.blockvisit(node.body, loop_frame, force_generator=True) |
| |
| if node.else_: |
| self.writeline('if l_loop is None:') |
| self.indent() |
| self.writeline('l_loop = ' + parent_loop) |
| self.outdent() |
| self.blockvisit(node.else_, loop_frame, force_generator=False) |
| |
| # reset the aliases if there are any. |
| for name, alias in aliases.iteritems(): |
| self.writeline('l_%s = %s' % (name, alias)) |
| |
| def visit_If(self, node, frame): |
| if_frame = frame.soft() |
| self.writeline('if ', node) |
| self.visit(node.test, if_frame) |
| self.write(':') |
| self.blockvisit(node.body, if_frame) |
| if node.else_: |
| self.writeline('else:') |
| self.blockvisit(node.else_, if_frame) |
| |
| def visit_Macro(self, node, frame): |
| macro_frame = self.function_scoping(node, frame) |
| args = macro_frame.arguments |
| self.writeline('def macro(%s):' % ', '.join(args), node) |
| macro_frame.buffer = buf = self.temporary_identifier() |
| self.indent() |
| self.pull_locals(macro_frame, indent=False) |
| self.writeline('%s = []' % buf) |
| self.blockvisit(node.body, macro_frame, indent=False) |
| self.writeline("return Markup(concat(%s))" % buf) |
| self.outdent() |
| self.newline() |
| if frame.toplevel: |
| self.write('context[%r] = ' % node.name) |
| arg_tuple = ', '.join(repr(x.name) for x in node.args) |
| if len(node.args) == 1: |
| arg_tuple += ',' |
| self.write('l_%s = Macro(environment, macro, %r, (%s), (' % |
| (node.name, node.name, arg_tuple)) |
| for arg in node.defaults: |
| self.visit(arg, macro_frame) |
| self.write(', ') |
| self.write('), %s, %s, %s)' % ( |
| macro_frame.accesses_kwargs and '1' or '0', |
| macro_frame.accesses_varargs and '1' or '0', |
| macro_frame.accesses_caller and '1' or '0' |
| )) |
| |
| def visit_CallBlock(self, node, frame): |
| call_frame = self.function_scoping(node, frame) |
| args = call_frame.arguments |
| self.writeline('def call(%s):' % ', '.join(args), node) |
| call_frame.buffer = buf = self.temporary_identifier() |
| self.indent() |
| self.pull_locals(call_frame, indent=False) |
| self.writeline('%s = []' % buf) |
| self.blockvisit(node.body, call_frame, indent=False) |
| self.writeline("return Markup(concat(%s))" % buf) |
| self.outdent() |
| arg_tuple = ', '.join(repr(x.name) for x in node.args) |
| if len(node.args) == 1: |
| arg_tuple += ',' |
| self.writeline('caller = Macro(environment, call, None, (%s), (' % |
| arg_tuple) |
| for arg in node.defaults: |
| self.visit(arg) |
| self.write(', ') |
| self.write('), %s, %s, 0)' % ( |
| call_frame.accesses_kwargs and '1' or '0', |
| call_frame.accesses_varargs and '1' or '0' |
| )) |
| if frame.buffer is None: |
| self.writeline('yield ', node) |
| else: |
| self.writeline('%s.append(' % frame.buffer, node) |
| self.visit_Call(node.call, call_frame, |
| extra_kwargs={'caller': 'caller'}) |
| if frame.buffer is not None: |
| self.write(')') |
| |
| def visit_FilterBlock(self, node, frame): |
| filter_frame = frame.inner() |
| filter_frame.inspect(node.iter_child_nodes()) |
| |
| aliases = self.collect_shadowed(filter_frame) |
| self.pull_locals(filter_frame, indent=False) |
| filter_frame.buffer = buf = self.temporary_identifier() |
| |
| self.writeline('%s = []' % buf, node) |
| for child in node.body: |
| self.visit(child, filter_frame) |
| |
| if frame.buffer is None: |
| self.writeline('yield ', node) |
| else: |
| self.writeline('%s.append(' % frame.buffer, node) |
| self.visit_Filter(node.filter, filter_frame, 'concat(%s)' % buf) |
| if frame.buffer is not None: |
| self.write(')') |
| |
| 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 self.has_known_extends and frame.toplevel: |
| return |
| |
| self.newline(node) |
| if self.environment.finalize is unicode: |
| finalizer = 'unicode' |
| have_finalizer = False |
| else: |
| finalizer = 'environment.finalize' |
| have_finalizer = True |
| |
| # if we are in the toplevel scope and there was already an extends |
| # statement we have to add a check that disables our yield(s) here |
| # so that they don't appear in the output. |
| outdent_later = False |
| if frame.toplevel and self.extends_so_far != 0: |
| 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: |
| const = unicode(child.as_const()) |
| except: |
| 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 we just yield them |
| if len(body) < 3: |
| for item in body: |
| if isinstance(item, list): |
| val = repr(concat(item)) |
| if frame.buffer is None: |
| self.writeline('yield ' + val) |
| else: |
| self.writeline('%s.append(%s)' % (frame.buffer, val)) |
| else: |
| self.newline(item) |
| if frame.buffer is None: |
| self.write('yield ') |
| else: |
| self.write('%s.append(' % frame.buffer) |
| self.write(finalizer + '(') |
| self.visit(item, frame) |
| self.write(')' * (1 + (frame.buffer is not None))) |
| |
| # 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) |
| if frame.buffer is None: |
| self.writeline('yield ') |
| else: |
| self.writeline('%s.append(' % frame.buffer) |
| self.write(repr(concat(format)) + ' % (') |
| idx = -1 |
| self.indent() |
| for argument in arguments: |
| self.newline(argument) |
| if have_finalizer: |
| self.write(finalizer + '(') |
| self.visit(argument, frame) |
| if have_finalizer: |
| self.write(')') |
| self.write(',') |
| self.outdent() |
| self.writeline(')') |
| if frame.buffer is not None: |
| self.write(')') |
| |
| if outdent_later: |
| self.outdent() |
| |
| def visit_Assign(self, node, frame): |
| self.newline(node) |
| # toplevel assignments however go into the local namespace and |
| # the current template's context. We create a copy of the frame |
| # here and add a set so that the Name visitor can add the assigned |
| # names here. |
| if frame.toplevel: |
| assignment_frame = frame.copy() |
| assignment_frame.assigned_names = set() |
| else: |
| assignment_frame = frame |
| self.visit(node.target, assignment_frame) |
| self.write(' = ') |
| self.visit(node.node, frame) |
| |
| # make sure toplevel assignments are added to the context. |
| if frame.toplevel: |
| for name in assignment_frame.assigned_names: |
| self.writeline('context[%r] = l_%s' % (name, name)) |
| |
| def visit_Name(self, node, frame): |
| if node.ctx == 'store': |
| if frame.toplevel: |
| frame.assigned_names.add(node.name) |
| frame.name_overrides.pop(node.name, None) |
| elif node.ctx == 'load': |
| if node.name in frame.name_overrides: |
| self.write(frame.name_overrides[node.name]) |
| return |
| self.write('l_' + node.name) |
| |
| def visit_Const(self, node, frame): |
| val = node.value |
| if isinstance(val, float): |
| # XXX: add checks for infinity and nan |
| self.write(str(val)) |
| else: |
| self.write(repr(val)) |
| |
| 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): |
| def visitor(self, node, frame): |
| self.write('(') |
| self.visit(node.left, frame) |
| self.write(' %s ' % operator) |
| self.visit(node.right, frame) |
| self.write(')') |
| return visitor |
| |
| def uaop(operator): |
| def visitor(self, node, frame): |
| 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') |
| visit_Or = binop('or') |
| visit_Pos = uaop('+') |
| visit_Neg = uaop('-') |
| visit_Not = uaop('not ') |
| del binop, uaop |
| |
| 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) |
| |
| def visit_Subscript(self, node, frame): |
| if isinstance(node.arg, nodes.Slice): |
| self.visit(node.node, frame) |
| self.write('[') |
| self.visit(node.arg, frame) |
| self.write(']') |
| return |
| try: |
| const = node.arg.as_const() |
| have_const = True |
| except nodes.Impossible: |
| have_const = False |
| self.write('environment.subscribe(') |
| self.visit(node.node, frame) |
| self.write(', ') |
| if have_const: |
| self.write(repr(const)) |
| else: |
| 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) |
| |
| def visit_Filter(self, node, frame, initial=None): |
| self.write('f_%s(' % node.name) |
| func = self.environment.filters.get(node.name) |
| if func is None: |
| raise TemplateAssertionError('no filter named %r' % node.name, |
| node.lineno, self.filename) |
| if getattr(func, 'contextfilter', False): |
| self.write('context, ') |
| elif getattr(func, 'environmentfilter', False): |
| self.write('environment, ') |
| if isinstance(node.node, nodes.Filter): |
| self.visit_Filter(node.node, frame, initial) |
| elif node.node is None: |
| self.write(initial) |
| else: |
| self.visit(node.node, frame) |
| self.signature(node, frame) |
| self.write(')') |
| |
| def visit_Test(self, node, frame): |
| self.write('t_%s(' % node.name) |
| if node.name not in self.environment.tests: |
| raise TemplateAssertionError('no test named %r' % node.name, |
| node.lineno, self.filename) |
| self.visit(node.node, frame) |
| self.signature(node, frame) |
| self.write(')') |
| |
| def visit_CondExpr(self, node, frame): |
| if not have_condexpr: |
| self.write('((') |
| self.visit(node.test, frame) |
| self.write(') and (') |
| self.visit(node.expr1, frame) |
| self.write(',) or (') |
| self.visit(node.expr2, frame) |
| self.write(',))[0]') |
| else: |
| self.write('(') |
| self.visit(node.expr1, frame) |
| self.write(' if ') |
| self.visit(node.test, frame) |
| self.write(' else ') |
| self.visit(node.expr2, frame) |
| self.write(')') |
| |
| def visit_Call(self, node, frame, extra_kwargs=None): |
| if self.environment.sandboxed: |
| self.write('environment.call(') |
| self.visit(node.node, frame) |
| self.write(self.environment.sandboxed and ', ' or '(') |
| self.signature(node, frame, False, extra_kwargs) |
| self.write(')') |
| |
| def visit_Keyword(self, node, frame): |
| self.write(node.key + '=') |
| self.visit(node.value, frame) |