| """Compiles nodes from the parser into Python code.""" |
| import typing as t |
| from contextlib import contextmanager |
| from functools import update_wrapper |
| from io import StringIO |
| from itertools import chain |
| from keyword import iskeyword as is_python_keyword |
| |
| from markupsafe import escape |
| from markupsafe import Markup |
| |
| from . import nodes |
| from .exceptions import TemplateAssertionError |
| from .idtracking import Symbols |
| from .idtracking import VAR_LOAD_ALIAS |
| from .idtracking import VAR_LOAD_PARAMETER |
| from .idtracking import VAR_LOAD_RESOLVE |
| from .idtracking import VAR_LOAD_UNDEFINED |
| from .nodes import EvalContext |
| from .optimizer import Optimizer |
| from .utils import _PassArg |
| from .utils import concat |
| from .visitor import NodeVisitor |
| |
| if t.TYPE_CHECKING: |
| import typing_extensions as te |
| from .environment import Environment |
| |
| F = t.TypeVar("F", bound=t.Callable[..., t.Any]) |
| |
| operators = { |
| "eq": "==", |
| "ne": "!=", |
| "gt": ">", |
| "gteq": ">=", |
| "lt": "<", |
| "lteq": "<=", |
| "in": "in", |
| "notin": "not in", |
| } |
| |
| |
| def optimizeconst(f: F) -> F: |
| def new_func( |
| self: "CodeGenerator", node: nodes.Expr, frame: "Frame", **kwargs: t.Any |
| ) -> t.Any: |
| # Only optimize if the frame is not volatile |
| if self.optimizer is not None 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(t.cast(F, new_func), f) |
| |
| |
| def _make_binop(op: str) -> t.Callable[["CodeGenerator", nodes.BinExpr, "Frame"], None]: |
| @optimizeconst |
| def visitor(self: "CodeGenerator", node: nodes.BinExpr, frame: Frame) -> None: |
| if ( |
| self.environment.sandboxed |
| and op in self.environment.intercepted_binops # type: ignore |
| ): |
| self.write(f"environment.call_binop(context, {op!r}, ") |
| self.visit(node.left, frame) |
| self.write(", ") |
| self.visit(node.right, frame) |
| else: |
| self.write("(") |
| self.visit(node.left, frame) |
| self.write(f" {op} ") |
| self.visit(node.right, frame) |
| |
| self.write(")") |
| |
| return visitor |
| |
| |
| def _make_unop( |
| op: str, |
| ) -> t.Callable[["CodeGenerator", nodes.UnaryExpr, "Frame"], None]: |
| @optimizeconst |
| def visitor(self: "CodeGenerator", node: nodes.UnaryExpr, frame: Frame) -> None: |
| if ( |
| self.environment.sandboxed |
| and op in self.environment.intercepted_unops # type: ignore |
| ): |
| self.write(f"environment.call_unop(context, {op!r}, ") |
| self.visit(node.node, frame) |
| else: |
| self.write("(" + op) |
| self.visit(node.node, frame) |
| |
| self.write(")") |
| |
| return visitor |
| |
| |
| def generate( |
| node: nodes.Template, |
| environment: "Environment", |
| name: t.Optional[str], |
| filename: t.Optional[str], |
| stream: t.Optional[t.TextIO] = None, |
| defer_init: bool = False, |
| optimized: bool = True, |
| ) -> t.Optional[str]: |
| """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() # type: ignore |
| |
| return None |
| |
| |
| def has_safe_repr(value: t.Any) -> bool: |
| """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, str, Markup}: |
| return True |
| |
| if type(value) in {tuple, list, set, frozenset}: |
| return all(has_safe_repr(v) for v in value) |
| |
| if type(value) is dict: |
| return all(has_safe_repr(k) and has_safe_repr(v) for k, v in value.items()) |
| |
| return False |
| |
| |
| def find_undeclared( |
| nodes: t.Iterable[nodes.Node], names: t.Iterable[str] |
| ) -> t.Set[str]: |
| """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: |
| def __init__(self, node: t.Union[nodes.Macro, nodes.CallBlock]) -> None: |
| self.node = node |
| self.accesses_caller = False |
| self.accesses_kwargs = False |
| self.accesses_varargs = False |
| |
| |
| class Frame: |
| """Holds compile time information for us.""" |
| |
| def __init__( |
| self, |
| eval_ctx: EvalContext, |
| parent: t.Optional["Frame"] = None, |
| level: t.Optional[int] = None, |
| ) -> None: |
| self.eval_ctx = eval_ctx |
| |
| # the parent of this frame |
| self.parent = parent |
| |
| if parent is None: |
| self.symbols = Symbols(level=level) |
| |
| # in some dynamic inheritance situations the compiler needs to add |
| # write tests around output statements. |
| self.require_output_check = 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: t.Optional[str] = None |
| |
| # the name of the block we're in, otherwise None. |
| self.block: t.Optional[str] = None |
| |
| else: |
| self.symbols = Symbols(parent.symbols, level=level) |
| self.require_output_check = parent.require_output_check |
| self.buffer = parent.buffer |
| self.block = parent.block |
| |
| # 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 |
| |
| # variables set inside of loops and blocks should not affect outer frames, |
| # but they still needs to be kept track of as part of the active context. |
| self.loop_frame = False |
| self.block_frame = False |
| |
| # track whether the frame is being used in an if-statement or conditional |
| # expression as it determines which errors should be raised during runtime |
| # or compile time. |
| self.soft_frame = False |
| |
| def copy(self) -> "Frame": |
| """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: bool = False) -> "Frame": |
| """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) -> "Frame": |
| """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 and conditional |
| expressions. |
| """ |
| rv = self.copy() |
| rv.rootlevel = False |
| rv.soft_frame = True |
| 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) -> None: |
| self.filters: t.Set[str] = set() |
| self.tests: t.Set[str] = set() |
| |
| def visit_Filter(self, node: nodes.Filter) -> None: |
| self.generic_visit(node) |
| self.filters.add(node.name) |
| |
| def visit_Test(self, node: nodes.Test) -> None: |
| self.generic_visit(node) |
| self.tests.add(node.name) |
| |
| def visit_Block(self, node: nodes.Block) -> None: |
| """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: t.Iterable[str]) -> None: |
| self.names = set(names) |
| self.undeclared: t.Set[str] = set() |
| |
| def visit_Name(self, node: nodes.Name) -> None: |
| 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: nodes.Block) -> None: |
| """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: "Environment", |
| name: t.Optional[str], |
| filename: t.Optional[str], |
| stream: t.Optional[t.TextIO] = None, |
| defer_init: bool = False, |
| optimized: bool = True, |
| ) -> None: |
| if stream is None: |
| stream = StringIO() |
| self.environment = environment |
| self.name = name |
| self.filename = filename |
| self.stream = stream |
| self.created_block_context = False |
| self.defer_init = defer_init |
| self.optimizer: t.Optional[Optimizer] = None |
| |
| if optimized: |
| self.optimizer = Optimizer(environment) |
| |
| # aliases for imports |
| self.import_aliases: t.Dict[str, str] = {} |
| |
| # a registry for all blocks. Because blocks are moved out |
| # into the global python scope they are registered here |
| self.blocks: t.Dict[str, nodes.Block] = {} |
| |
| # 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: t.Dict[str, str] = {} |
| self.filters: t.Dict[str, str] = {} |
| |
| # the debug information |
| self.debug_info: t.List[t.Tuple[int, int]] = [] |
| self._write_debug_info: t.Optional[int] = 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: t.List[t.Set[str]] = [] |
| |
| # Tracks parameter definition blocks |
| self._param_def_block: t.List[t.Set[str]] = [] |
| |
| # Tracks the current context. |
| self._context_reference_stack = ["context"] |
| |
| @property |
| def optimized(self) -> bool: |
| return self.optimizer is not None |
| |
| # -- Various compilation helpers |
| |
| def fail(self, msg: str, lineno: int) -> "te.NoReturn": |
| """Fail with a :exc:`TemplateAssertionError`.""" |
| raise TemplateAssertionError(msg, lineno, self.name, self.filename) |
| |
| def temporary_identifier(self) -> str: |
| """Get a new unique identifier.""" |
| self._last_identifier += 1 |
| return f"t_{self._last_identifier}" |
| |
| def buffer(self, frame: Frame) -> None: |
| """Enable buffering for the frame from that point onwards.""" |
| frame.buffer = self.temporary_identifier() |
| self.writeline(f"{frame.buffer} = []") |
| |
| def return_buffer_contents( |
| self, frame: Frame, force_unescaped: bool = False |
| ) -> None: |
| """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(f"return Markup(concat({frame.buffer}))") |
| self.outdent() |
| self.writeline("else:") |
| self.indent() |
| self.writeline(f"return concat({frame.buffer})") |
| self.outdent() |
| return |
| elif frame.eval_ctx.autoescape: |
| self.writeline(f"return Markup(concat({frame.buffer}))") |
| return |
| self.writeline(f"return concat({frame.buffer})") |
| |
| def indent(self) -> None: |
| """Indent by one.""" |
| self._indentation += 1 |
| |
| def outdent(self, step: int = 1) -> None: |
| """Outdent by step.""" |
| self._indentation -= step |
| |
| def start_write(self, frame: Frame, node: t.Optional[nodes.Node] = None) -> None: |
| """Yield or write into the frame buffer.""" |
| if frame.buffer is None: |
| self.writeline("yield ", node) |
| else: |
| self.writeline(f"{frame.buffer}.append(", node) |
| |
| def end_write(self, frame: Frame) -> None: |
| """End the writing process started by `start_write`.""" |
| if frame.buffer is not None: |
| self.write(")") |
| |
| def simple_write( |
| self, s: str, frame: Frame, node: t.Optional[nodes.Node] = None |
| ) -> 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: t.Iterable[nodes.Node], frame: Frame) -> None: |
| """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: str) -> None: |
| """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: str, node: t.Optional[nodes.Node] = None, extra: int = 0 |
| ) -> None: |
| """Combination of newline and write.""" |
| self.newline(node, extra) |
| self.write(x) |
| |
| def newline(self, node: t.Optional[nodes.Node] = None, extra: int = 0) -> None: |
| """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: t.Union[nodes.Call, nodes.Filter, nodes.Test], |
| frame: Frame, |
| extra_kwargs: t.Optional[t.Mapping[str, t.Any]] = None, |
| ) -> 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 occur. 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 = any( |
| is_python_keyword(t.cast(str, k)) |
| for k in chain((x.key for x in node.kwargs), extra_kwargs or ()) |
| ) |
| |
| 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 extra_kwargs.items(): |
| self.write(f", {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(f"{kwarg.key!r}: ") |
| self.visit(kwarg.value, frame) |
| self.write(", ") |
| if extra_kwargs is not None: |
| for key, value in extra_kwargs.items(): |
| self.write(f"{key!r}: {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: t.Iterable[nodes.Node]) -> None: |
| """Find all filter and test names used in the template and |
| assign them to variables in the compiled namespace. Checking |
| that the names are registered with the environment is done when |
| compiling the Filter and Test nodes. If the node is in an If or |
| CondExpr node, the check is done at runtime instead. |
| |
| .. versionchanged:: 3.0 |
| Filters and tests in If and CondExpr nodes are checked at |
| runtime instead of compile time. |
| """ |
| visitor = DependencyFinderVisitor() |
| |
| for node in nodes: |
| visitor.visit(node) |
| |
| for id_map, names, dependency in (self.filters, visitor.filters, "filters"), ( |
| self.tests, |
| visitor.tests, |
| "tests", |
| ): |
| for name in sorted(names): |
| if name not in id_map: |
| id_map[name] = self.temporary_identifier() |
| |
| # add check during runtime that dependencies used inside of executed |
| # blocks are defined, as this step may be skipped during compile time |
| self.writeline("try:") |
| self.indent() |
| self.writeline(f"{id_map[name]} = environment.{dependency}[{name!r}]") |
| self.outdent() |
| self.writeline("except KeyError:") |
| self.indent() |
| self.writeline("@internalcode") |
| self.writeline(f"def {id_map[name]}(*unused):") |
| self.indent() |
| self.writeline( |
| f'raise TemplateRuntimeError("No {dependency[:-1]}' |
| f' named {name!r} found.")' |
| ) |
| self.outdent() |
| self.outdent() |
| |
| def enter_frame(self, frame: Frame) -> None: |
| undefs = [] |
| for target, (action, param) in frame.symbols.loads.items(): |
| if action == VAR_LOAD_PARAMETER: |
| pass |
| elif action == VAR_LOAD_RESOLVE: |
| self.writeline(f"{target} = {self.get_resolve_func()}({param!r})") |
| elif action == VAR_LOAD_ALIAS: |
| self.writeline(f"{target} = {param}") |
| elif action == VAR_LOAD_UNDEFINED: |
| undefs.append(target) |
| else: |
| raise NotImplementedError("unknown load instruction") |
| if undefs: |
| self.writeline(f"{' = '.join(undefs)} = missing") |
| |
| def leave_frame(self, frame: Frame, with_python_scope: bool = False) -> None: |
| if not with_python_scope: |
| undefs = [] |
| for target in frame.symbols.loads: |
| undefs.append(target) |
| if undefs: |
| self.writeline(f"{' = '.join(undefs)} = missing") |
| |
| def choose_async(self, async_value: str = "async ", sync_value: str = "") -> str: |
| return async_value if self.environment.is_async else sync_value |
| |
| def func(self, name: str) -> str: |
| return f"{self.choose_async()}def {name}" |
| |
| def macro_body( |
| self, node: t.Union[nodes.Macro, nodes.CallBlock], frame: Frame |
| ) -> t.Tuple[Frame, MacroRef]: |
| """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 Jinja 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 "kwargs" not in skip_special_params: |
| args.append(frame.symbols.declare_parameter("kwargs")) |
| macro_ref.accesses_kwargs = True |
| if "varargs" in undeclared and "varargs" not 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(f"{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(f"if {ref} is missing:") |
| self.indent() |
| try: |
| default = node.defaults[idx - len(node.args)] |
| except IndexError: |
| self.writeline( |
| f'{ref} = undefined("parameter {arg.name!r} was not provided",' |
| f" name={arg.name!r})" |
| ) |
| else: |
| self.writeline(f"{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: MacroRef, frame: Frame) -> None: |
| """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( |
| f"Macro(environment, macro, {name!r}, ({arg_tuple})," |
| f" {macro_ref.accesses_kwargs!r}, {macro_ref.accesses_varargs!r}," |
| f" {macro_ref.accesses_caller!r}, context.eval_ctx.autoescape)" |
| ) |
| |
| def position(self, node: nodes.Node) -> str: |
| """Return a human readable position for the node.""" |
| rv = f"line {node.lineno}" |
| if self.name is not None: |
| rv = f"{rv} in {self.name!r}" |
| return rv |
| |
| def dump_local_context(self, frame: Frame) -> str: |
| items_kv = ", ".join( |
| f"{name!r}: {target}" |
| for name, target in frame.symbols.dump_stores().items() |
| ) |
| return f"{{{items_kv}}}" |
| |
| def write_commons(self) -> None: |
| """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("concat = environment.concat") |
| # always use the standard Undefined class for the implicit else of |
| # conditional expressions |
| self.writeline("cond_expr_undefined = Undefined") |
| self.writeline("if 0: yield None") |
| |
| def push_parameter_definitions(self, frame: Frame) -> None: |
| """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) -> None: |
| """Pops the current parameter definitions set.""" |
| self._param_def_block.pop() |
| |
| def mark_parameter_stored(self, target: str) -> None: |
| """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: str) -> None: |
| self._context_reference_stack.append(target) |
| |
| def pop_context_reference(self) -> None: |
| self._context_reference_stack.pop() |
| |
| def get_context_ref(self) -> str: |
| return self._context_reference_stack[-1] |
| |
| def get_resolve_func(self) -> str: |
| target = self._context_reference_stack[-1] |
| if target == "context": |
| return "resolve" |
| return f"{target}.resolve" |
| |
| def derive_context(self, frame: Frame) -> str: |
| return f"{self.get_context_ref()}.derived({self.dump_local_context(frame)})" |
| |
| def parameter_is_undeclared(self, target: str) -> bool: |
| """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) -> None: |
| """Pushes a new layer for assignment tracking.""" |
| self._assign_stack.append(set()) |
| |
| def pop_assign_tracking(self, frame: Frame) -> None: |
| """Pops the topmost level for assignment tracking and updates the |
| context variables if necessary. |
| """ |
| vars = self._assign_stack.pop() |
| if ( |
| not frame.block_frame |
| and not frame.loop_frame |
| and 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) |
| if frame.loop_frame: |
| self.writeline(f"_loop_vars[{name!r}] = {ref}") |
| return |
| if frame.block_frame: |
| self.writeline(f"_block_vars[{name!r}] = {ref}") |
| return |
| self.writeline(f"context.vars[{name!r}] = {ref}") |
| else: |
| if frame.loop_frame: |
| self.writeline("_loop_vars.update({") |
| elif frame.block_frame: |
| self.writeline("_block_vars.update({") |
| else: |
| self.writeline("context.vars.update({") |
| for idx, name in enumerate(vars): |
| if idx: |
| self.write(", ") |
| ref = frame.symbols.ref(name) |
| self.write(f"{name!r}: {ref}") |
| self.write("})") |
| if not frame.block_frame and not frame.loop_frame and public_names: |
| if len(public_names) == 1: |
| self.writeline(f"context.exported_vars.add({public_names[0]!r})") |
| else: |
| names_str = ", ".join(map(repr, public_names)) |
| self.writeline(f"context.exported_vars.update(({names_str}))") |
| |
| # -- Statement Visitors |
| |
| def visit_Template( |
| self, node: nodes.Template, frame: t.Optional[Frame] = None |
| ) -> None: |
| assert frame is None, "no root frame allowed" |
| eval_ctx = EvalContext(self.environment, self.name) |
| |
| from .runtime import exported, async_exported |
| |
| if self.environment.is_async: |
| exported_names = sorted(exported + async_exported) |
| else: |
| exported_names = sorted(exported) |
| |
| self.writeline("from jinja2.runtime import " + ", ".join(exported_names)) |
| |
| # if we want a deferred initialization we cannot move the |
| # environment into a local name |
| envenv = "" if self.defer_init else ", environment=environment" |
| |
| # 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(f"block {block.name!r} defined twice", 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(f"from {module} import {obj} as {alias}") |
| else: |
| self.writeline(f"import {imp} as {alias}") |
| |
| # add the load name |
| self.writeline(f"name = {self.name!r}") |
| |
| # generate the root render function. |
| self.writeline( |
| f"{self.func('root')}(context, missing=missing{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(f"{ref} = TemplateReference(context)") |
| 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 not self.environment.is_async: |
| self.writeline("yield from parent_template.root_render_func(context)") |
| else: |
| self.writeline( |
| "async for event in parent_template.root_render_func(context):" |
| ) |
| 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 self.blocks.items(): |
| self.writeline( |
| f"{self.func('block_' + name)}(context, missing=missing{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) |
| block_frame.block_frame = True |
| undeclared = find_undeclared(block.body, ("self", "super")) |
| if "self" in undeclared: |
| ref = block_frame.symbols.declare_parameter("self") |
| self.writeline(f"{ref} = TemplateReference(context)") |
| if "super" in undeclared: |
| ref = block_frame.symbols.declare_parameter("super") |
| self.writeline(f"{ref} = context.super({name!r}, block_{name})") |
| block_frame.symbols.analyze_node(block) |
| block_frame.block = name |
| self.writeline("_block_vars = {}") |
| 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() |
| |
| blocks_kv_str = ", ".join(f"{x!r}: block_{x}" for x in self.blocks) |
| self.writeline(f"blocks = {{{blocks_kv_str}}}", extra=1) |
| debug_kv_str = "&".join(f"{k}={v}" for k, v in self.debug_info) |
| self.writeline(f"debug_info = {debug_kv_str!r}") |
| |
| def visit_Block(self, node: nodes.Block, frame: Frame) -> None: |
| """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 node.required: |
| self.writeline(f"if len(context.blocks[{node.name!r}]) <= 1:", node) |
| self.indent() |
| self.writeline( |
| f'raise TemplateRuntimeError("Required block {node.name!r} not found")', |
| node, |
| ) |
| self.outdent() |
| |
| if not self.environment.is_async and frame.buffer is None: |
| self.writeline( |
| f"yield from context.blocks[{node.name!r}][0]({context})", node |
| ) |
| else: |
| self.writeline( |
| f"{self.choose_async()}for event in" |
| f" context.blocks[{node.name!r}][0]({context}):", |
| node, |
| ) |
| self.indent() |
| self.simple_write("event", frame) |
| self.outdent() |
| |
| self.outdent(level) |
| |
| def visit_Extends(self, node: nodes.Extends, frame: Frame) -> None: |
| """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("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(f", {self.name!r})") |
| self.writeline("for name, parent_block in parent_template.blocks.items():") |
| 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: nodes.Include, frame: Frame) -> None: |
| """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, str): |
| 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(f"template = environment.{func_name}(", node) |
| self.visit(node.template, frame) |
| self.write(f", {self.name!r})") |
| 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: |
| self.writeline( |
| f"{self.choose_async()}for event in template.root_render_func(" |
| "template.new_context(context.get_all(), True," |
| f" {self.dump_local_context(frame)})):" |
| ) |
| elif self.environment.is_async: |
| self.writeline( |
| "for event in (await template._get_default_module_async())" |
| "._body_stream:" |
| ) |
| else: |
| self.writeline("yield from template._get_default_module()._body_stream") |
| skip_event_yield = True |
| |
| if not skip_event_yield: |
| self.indent() |
| self.simple_write("event", frame) |
| self.outdent() |
| |
| if node.ignore_missing: |
| self.outdent() |
| |
| def _import_common( |
| self, node: t.Union[nodes.Import, nodes.FromImport], frame: Frame |
| ) -> None: |
| self.write(f"{self.choose_async('await ')}environment.get_template(") |
| self.visit(node.template, frame) |
| self.write(f", {self.name!r}).") |
| |
| if node.with_context: |
| f_name = f"make_module{self.choose_async('_async')}" |
| self.write( |
| f"{f_name}(context.get_all(), True, {self.dump_local_context(frame)})" |
| ) |
| else: |
| self.write(f"_get_default_module{self.choose_async('_async')}(context)") |
| |
| def visit_Import(self, node: nodes.Import, frame: Frame) -> None: |
| """Visit regular imports.""" |
| self.writeline(f"{frame.symbols.ref(node.target)} = ", node) |
| if frame.toplevel: |
| self.write(f"context.vars[{node.target!r}] = ") |
| |
| self._import_common(node, frame) |
| |
| if frame.toplevel and not node.target.startswith("_"): |
| self.writeline(f"context.exported_vars.discard({node.target!r})") |
| |
| def visit_FromImport(self, node: nodes.FromImport, frame: Frame) -> None: |
| """Visit named imports.""" |
| self.newline(node) |
| self.write("included_template = ") |
| self._import_common(node, frame) |
| var_names = [] |
| discarded_names = [] |
| for name in node.names: |
| if isinstance(name, tuple): |
| name, alias = name |
| else: |
| alias = name |
| self.writeline( |
| f"{frame.symbols.ref(alias)} =" |
| f" getattr(included_template, {name!r}, missing)" |
| ) |
| self.writeline(f"if {frame.symbols.ref(alias)} is missing:") |
| self.indent() |
| message = ( |
| "the template {included_template.__name__!r}" |
| f" (imported on {self.position(node)})" |
| f" does not export the requested name {name!r}" |
| ) |
| self.writeline( |
| f"{frame.symbols.ref(alias)} = undefined(f{message!r}, name={name!r})" |
| ) |
| 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(f"context.vars[{name!r}] = {frame.symbols.ref(name)}") |
| else: |
| names_kv = ", ".join( |
| f"{name!r}: {frame.symbols.ref(name)}" for name in var_names |
| ) |
| self.writeline(f"context.vars.update({{{names_kv}}})") |
| if discarded_names: |
| if len(discarded_names) == 1: |
| self.writeline(f"context.exported_vars.discard({discarded_names[0]!r})") |
| else: |
| names_str = ", ".join(map(repr, discarded_names)) |
| self.writeline( |
| f"context.exported_vars.difference_update(({names_str}))" |
| ) |
| |
| def visit_For(self, node: nodes.For, frame: Frame) -> None: |
| loop_frame = frame.inner() |
| loop_frame.loop_frame = True |
| 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 if the body is a scoped block. |
| extended_loop = ( |
| node.recursive |
| or "loop" |
| in find_undeclared(node.iter_child_nodes(only=("body",)), ("loop",)) |
| or any(block.scoped for block in node.find_all(nodes.Block)) |
| ) |
| |
| 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(f"{self.func(loop_filter_func)}(fiter):", node.test) |
| self.indent() |
| self.enter_frame(test_frame) |
| self.writeline(self.choose_async("async for ", "for ")) |
| self.visit(node.target, loop_frame) |
| self.write(" in ") |
| self.write(self.choose_async("auto_aiter(fiter)", "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( |
| f"{self.func('loop')}(reciter, loop_render_func, depth=0):", 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(f"{loop_ref} = missing") |
| |
| 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(f"{iteration_indicator} = 1") |
| |
| self.writeline(self.choose_async("async for ", "for "), node) |
| self.visit(node.target, loop_frame) |
| if extended_loop: |
| self.write(f", {loop_ref} in {self.choose_async('Async')}LoopContext(") |
| else: |
| self.write(" in ") |
| |
| if node.test: |
| self.write(f"{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(", undefined):" if extended_loop else ":") |
| |
| self.indent() |
| self.enter_frame(loop_frame) |
| |
| self.writeline("_loop_vars = {}") |
| self.blockvisit(node.body, loop_frame) |
| if node.else_: |
| self.writeline(f"{iteration_indicator} = 0") |
| self.outdent() |
| self.leave_frame( |
| loop_frame, with_python_scope=node.recursive and not node.else_ |
| ) |
| |
| if node.else_: |
| self.writeline(f"if {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) |
| self.write(f"{self.choose_async('await ')}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) |
| |
| # at the end of the iteration, clear any assignments made in the |
| # loop from the top level |
| if self._assign_stack: |
| self._assign_stack[-1].difference_update(loop_frame.symbols.stores) |
| |
| def visit_If(self, node: nodes.If, frame: Frame) -> None: |
| 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: nodes.Macro, frame: Frame) -> None: |
| macro_frame, macro_ref = self.macro_body(node, frame) |
| self.newline() |
| if frame.toplevel: |
| if not node.name.startswith("_"): |
| self.write(f"context.exported_vars.add({node.name!r})") |
| self.writeline(f"context.vars[{node.name!r}] = ") |
| self.write(f"{frame.symbols.ref(node.name)} = ") |
| self.macro_def(macro_ref, macro_frame) |
| |
| def visit_CallBlock(self, node: nodes.CallBlock, frame: Frame) -> None: |
| 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: nodes.FilterBlock, frame: Frame) -> None: |
| 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: nodes.With, frame: Frame) -> None: |
| with_frame = frame.inner() |
| with_frame.symbols.analyze_node(node) |
| self.enter_frame(with_frame) |
| for target, expr in zip(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: nodes.ExprStmt, frame: Frame) -> None: |
| self.newline(node) |
| self.visit(node.node, frame) |
| |
| class _FinalizeInfo(t.NamedTuple): |
| const: t.Optional[t.Callable[..., str]] |
| src: t.Optional[str] |
| |
| @staticmethod |
| def _default_finalize(value: t.Any) -> t.Any: |
| """The default finalize function if the environment isn't |
| configured with one. Or, if the environment has one, this is |
| called on that function's output for constants. |
| """ |
| return str(value) |
| |
| _finalize: t.Optional[_FinalizeInfo] = None |
| |
| def _make_finalize(self) -> _FinalizeInfo: |
| """Build the finalize function to be used on constants and at |
| runtime. Cached so it's only created once for all output nodes. |
| |
| Returns a ``namedtuple`` with the following attributes: |
| |
| ``const`` |
| A function to finalize constant data at compile time. |
| |
| ``src`` |
| Source code to output around nodes to be evaluated at |
| runtime. |
| """ |
| if self._finalize is not None: |
| return self._finalize |
| |
| finalize: t.Optional[t.Callable[..., t.Any]] |
| finalize = default = self._default_finalize |
| src = None |
| |
| if self.environment.finalize: |
| src = "environment.finalize(" |
| env_finalize = self.environment.finalize |
| pass_arg = { |
| _PassArg.context: "context", |
| _PassArg.eval_context: "context.eval_ctx", |
| _PassArg.environment: "environment", |
| }.get( |
| _PassArg.from_obj(env_finalize) # type: ignore |
| ) |
| finalize = None |
| |
| if pass_arg is None: |
| |
| def finalize(value: t.Any) -> t.Any: |
| return default(env_finalize(value)) |
| |
| else: |
| src = f"{src}{pass_arg}, " |
| |
| if pass_arg == "environment": |
| |
| def finalize(value: t.Any) -> t.Any: |
| return default(env_finalize(self.environment, value)) |
| |
| self._finalize = self._FinalizeInfo(finalize, src) |
| return self._finalize |
| |
| def _output_const_repr(self, group: t.Iterable[t.Any]) -> str: |
| """Given a group of constant values converted from ``Output`` |
| child nodes, produce a string to write to the template module |
| source. |
| """ |
| return repr(concat(group)) |
| |
| def _output_child_to_const( |
| self, node: nodes.Expr, frame: Frame, finalize: _FinalizeInfo |
| ) -> str: |
| """Try to optimize a child of an ``Output`` node by trying to |
| convert it to constant, finalized data at compile time. |
| |
| If :exc:`Impossible` is raised, the node is not constant and |
| will be evaluated at runtime. Any other exception will also be |
| evaluated at runtime for easier debugging. |
| """ |
| const = node.as_const(frame.eval_ctx) |
| |
| if frame.eval_ctx.autoescape: |
| const = escape(const) |
| |
| # Template data doesn't go through finalize. |
| if isinstance(node, nodes.TemplateData): |
| return str(const) |
| |
| return finalize.const(const) # type: ignore |
| |
| def _output_child_pre( |
| self, node: nodes.Expr, frame: Frame, finalize: _FinalizeInfo |
| ) -> None: |
| """Output extra source code before visiting a child of an |
| ``Output`` node. |
| """ |
| if frame.eval_ctx.volatile: |
| self.write("(escape if context.eval_ctx.autoescape else str)(") |
| elif frame.eval_ctx.autoescape: |
| self.write("escape(") |
| else: |
| self.write("str(") |
| |
| if finalize.src is not None: |
| self.write(finalize.src) |
| |
| def _output_child_post( |
| self, node: nodes.Expr, frame: Frame, finalize: _FinalizeInfo |
| ) -> None: |
| """Output extra source code after visiting a child of an |
| ``Output`` node. |
| """ |
| self.write(")") |
| |
| if finalize.src is not None: |
| self.write(")") |
| |
| def visit_Output(self, node: nodes.Output, frame: Frame) -> None: |
| # If an extends is active, don't render outside a block. |
| if frame.require_output_check: |
| # A top-level extends is known to exist at compile time. |
| if self.has_known_extends: |
| return |
| |
| self.writeline("if parent_template is None:") |
| self.indent() |
| |
| finalize = self._make_finalize() |
| body: t.List[t.Union[t.List[t.Any], nodes.Expr]] = [] |
| |
| # Evaluate constants at compile time if possible. Each item in |
| # body will be either a list of static data or a node to be |
| # evaluated at runtime. |
| for child in node.nodes: |
| try: |
| if not ( |
| # If the finalize function requires runtime context, |
| # constants can't be evaluated at compile time. |
| finalize.const |
| # Unless it's basic template data that won't be |
| # finalized anyway. |
| or isinstance(child, nodes.TemplateData) |
| ): |
| raise nodes.Impossible() |
| |
| const = self._output_child_to_const(child, frame, finalize) |
| except (nodes.Impossible, Exception): |
| # The node was not constant and needs to be evaluated at |
| # runtime. Or another error was raised, which is easier |
| # to debug at runtime. |
| body.append(child) |
| continue |
| |
| if body and isinstance(body[-1], list): |
| body[-1].append(const) |
| else: |
| body.append([const]) |
| |
| if frame.buffer is not None: |
| if len(body) == 1: |
| self.writeline(f"{frame.buffer}.append(") |
| else: |
| self.writeline(f"{frame.buffer}.extend((") |
| |
| self.indent() |
| |
| for item in body: |
| if isinstance(item, list): |
| # A group of constant data to join and output. |
| val = self._output_const_repr(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) |
| |
| # A node to be evaluated at runtime. |
| self._output_child_pre(item, frame, finalize) |
| self.visit(item, frame) |
| self._output_child_post(item, frame, finalize) |
| |
| if frame.buffer is not None: |
| self.write(",") |
| |
| if frame.buffer is not None: |
| self.outdent() |
| self.writeline(")" if len(body) == 1 else "))") |
| |
| if frame.require_output_check: |
| self.outdent() |
| |
| def visit_Assign(self, node: nodes.Assign, frame: Frame) -> None: |
| 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: nodes.AssignBlock, frame: Frame) -> None: |
| 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(f"concat({block_frame.buffer})") |
| self.write(")") |
| self.pop_assign_tracking(frame) |
| self.leave_frame(block_frame) |
| |
| # -- Expression Visitors |
| |
| def visit_Name(self, node: nodes.Name, frame: Frame) -> None: |
| if node.ctx == "store" and ( |
| frame.toplevel or frame.loop_frame or frame.block_frame |
| ): |
| 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( |
| f"(undefined(name={node.name!r}) if {ref} is missing else {ref})" |
| ) |
| return |
| |
| self.write(ref) |
| |
| def visit_NSRef(self, node: nodes.NSRef, frame: Frame) -> None: |
| # 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(f"if not isinstance({ref}, Namespace):") |
| self.indent() |
| self.writeline( |
| "raise TemplateRuntimeError" |
| '("cannot assign attribute on non-namespace object")' |
| ) |
| self.outdent() |
| self.writeline(f"{ref}[{node.attr!r}]") |
| |
| def visit_Const(self, node: nodes.Const, frame: Frame) -> None: |
| 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: nodes.TemplateData, frame: Frame) -> None: |
| try: |
| self.write(repr(node.as_const(frame.eval_ctx))) |
| except nodes.Impossible: |
| self.write( |
| f"(Markup if context.eval_ctx.autoescape else identity)({node.data!r})" |
| ) |
| |
| def visit_Tuple(self, node: nodes.Tuple, frame: Frame) -> None: |
| self.write("(") |
| idx = -1 |
| for idx, item in enumerate(node.items): |
| if idx: |
| self.write(", ") |
| self.visit(item, frame) |
| self.write(",)" if idx == 0 else ")") |
| |
| def visit_List(self, node: nodes.List, frame: Frame) -> None: |
| self.write("[") |
| for idx, item in enumerate(node.items): |
| if idx: |
| self.write(", ") |
| self.visit(item, frame) |
| self.write("]") |
| |
| def visit_Dict(self, node: nodes.Dict, frame: Frame) -> None: |
| 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("}") |
| |
| visit_Add = _make_binop("+") |
| visit_Sub = _make_binop("-") |
| visit_Mul = _make_binop("*") |
| visit_Div = _make_binop("/") |
| visit_FloorDiv = _make_binop("//") |
| visit_Pow = _make_binop("**") |
| visit_Mod = _make_binop("%") |
| visit_And = _make_binop("and") |
| visit_Or = _make_binop("or") |
| visit_Pos = _make_unop("+") |
| visit_Neg = _make_unop("-") |
| visit_Not = _make_unop("not ") |
| |
| @optimizeconst |
| def visit_Concat(self, node: nodes.Concat, frame: Frame) -> None: |
| if frame.eval_ctx.volatile: |
| func_name = "(markup_join if context.eval_ctx.volatile else str_join)" |
| elif frame.eval_ctx.autoescape: |
| func_name = "markup_join" |
| else: |
| func_name = "str_join" |
| self.write(f"{func_name}((") |
| for arg in node.nodes: |
| self.visit(arg, frame) |
| self.write(", ") |
| self.write("))") |
| |
| @optimizeconst |
| def visit_Compare(self, node: nodes.Compare, frame: Frame) -> None: |
| self.write("(") |
| self.visit(node.expr, frame) |
| for op in node.ops: |
| self.visit(op, frame) |
| self.write(")") |
| |
| def visit_Operand(self, node: nodes.Operand, frame: Frame) -> None: |
| self.write(f" {operators[node.op]} ") |
| self.visit(node.expr, frame) |
| |
| @optimizeconst |
| def visit_Getattr(self, node: nodes.Getattr, frame: Frame) -> None: |
| if self.environment.is_async: |
| self.write("(await auto_await(") |
| |
| self.write("environment.getattr(") |
| self.visit(node.node, frame) |
| self.write(f", {node.attr!r})") |
| |
| if self.environment.is_async: |
| self.write("))") |
| |
| @optimizeconst |
| def visit_Getitem(self, node: nodes.Getitem, frame: Frame) -> None: |
| # 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: |
| if self.environment.is_async: |
| self.write("(await auto_await(") |
| |
| self.write("environment.getitem(") |
| self.visit(node.node, frame) |
| self.write(", ") |
| self.visit(node.arg, frame) |
| self.write(")") |
| |
| if self.environment.is_async: |
| self.write("))") |
| |
| def visit_Slice(self, node: nodes.Slice, frame: Frame) -> None: |
| 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) |
| |
| @contextmanager |
| def _filter_test_common( |
| self, node: t.Union[nodes.Filter, nodes.Test], frame: Frame, is_filter: bool |
| ) -> t.Iterator[None]: |
| if self.environment.is_async: |
| self.write("(await auto_await(") |
| |
| if is_filter: |
| self.write(f"{self.filters[node.name]}(") |
| func = self.environment.filters.get(node.name) |
| else: |
| self.write(f"{self.tests[node.name]}(") |
| func = self.environment.tests.get(node.name) |
| |
| # When inside an If or CondExpr frame, allow the filter to be |
| # undefined at compile time and only raise an error if it's |
| # actually called at runtime. See pull_dependencies. |
| if func is None and not frame.soft_frame: |
| type_name = "filter" if is_filter else "test" |
| self.fail(f"No {type_name} named {node.name!r}.", node.lineno) |
| |
| pass_arg = { |
| _PassArg.context: "context", |
| _PassArg.eval_context: "context.eval_ctx", |
| _PassArg.environment: "environment", |
| }.get( |
| _PassArg.from_obj(func) # type: ignore |
| ) |
| |
| if pass_arg is not None: |
| self.write(f"{pass_arg}, ") |
| |
| # Back to the visitor function to handle visiting the target of |
| # the filter or test. |
| yield |
| |
| self.signature(node, frame) |
| self.write(")") |
| |
| if self.environment.is_async: |
| self.write("))") |
| |
| @optimizeconst |
| def visit_Filter(self, node: nodes.Filter, frame: Frame) -> None: |
| with self._filter_test_common(node, frame, True): |
| # 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( |
| f"(Markup(concat({frame.buffer}))" |
| f" if context.eval_ctx.autoescape else concat({frame.buffer}))" |
| ) |
| elif frame.eval_ctx.autoescape: |
| self.write(f"Markup(concat({frame.buffer}))") |
| else: |
| self.write(f"concat({frame.buffer})") |
| |
| @optimizeconst |
| def visit_Test(self, node: nodes.Test, frame: Frame) -> None: |
| with self._filter_test_common(node, frame, False): |
| self.visit(node.node, frame) |
| |
| @optimizeconst |
| def visit_CondExpr(self, node: nodes.CondExpr, frame: Frame) -> None: |
| frame = frame.soft() |
| |
| def write_expr2() -> None: |
| if node.expr2 is not None: |
| self.visit(node.expr2, frame) |
| return |
| |
| self.write( |
| f'cond_expr_undefined("the inline if-expression on' |
| f" {self.position(node)} evaluated to false and no else" |
| f' section was defined.")' |
| ) |
| |
| 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: nodes.Call, frame: Frame, forward_caller: bool = False |
| ) -> None: |
| 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 = {"caller": "caller"} if forward_caller else None |
| loop_kwargs = {"_loop_vars": "_loop_vars"} if frame.loop_frame else {} |
| block_kwargs = {"_block_vars": "_block_vars"} if frame.block_frame else {} |
| if extra_kwargs: |
| extra_kwargs.update(loop_kwargs, **block_kwargs) |
| elif loop_kwargs or block_kwargs: |
| extra_kwargs = dict(loop_kwargs, **block_kwargs) |
| self.signature(node, frame, extra_kwargs) |
| self.write(")") |
| if self.environment.is_async: |
| self.write("))") |
| |
| def visit_Keyword(self, node: nodes.Keyword, frame: Frame) -> None: |
| self.write(node.key + "=") |
| self.visit(node.value, frame) |
| |
| # -- Unused nodes for extensions |
| |
| def visit_MarkSafe(self, node: nodes.MarkSafe, frame: Frame) -> None: |
| self.write("Markup(") |
| self.visit(node.expr, frame) |
| self.write(")") |
| |
| def visit_MarkSafeIfAutoescape( |
| self, node: nodes.MarkSafeIfAutoescape, frame: Frame |
| ) -> None: |
| self.write("(Markup if context.eval_ctx.autoescape else identity)(") |
| self.visit(node.expr, frame) |
| self.write(")") |
| |
| def visit_EnvironmentAttribute( |
| self, node: nodes.EnvironmentAttribute, frame: Frame |
| ) -> None: |
| self.write("environment." + node.name) |
| |
| def visit_ExtensionAttribute( |
| self, node: nodes.ExtensionAttribute, frame: Frame |
| ) -> None: |
| self.write(f"environment.extensions[{node.identifier!r}].{node.name}") |
| |
| def visit_ImportedName(self, node: nodes.ImportedName, frame: Frame) -> None: |
| self.write(self.import_aliases[node.importname]) |
| |
| def visit_InternalName(self, node: nodes.InternalName, frame: Frame) -> None: |
| self.write(node.name) |
| |
| def visit_ContextReference( |
| self, node: nodes.ContextReference, frame: Frame |
| ) -> None: |
| self.write("context") |
| |
| def visit_DerivedContextReference( |
| self, node: nodes.DerivedContextReference, frame: Frame |
| ) -> None: |
| self.write(self.derive_context(frame)) |
| |
| def visit_Continue(self, node: nodes.Continue, frame: Frame) -> None: |
| self.writeline("continue", node) |
| |
| def visit_Break(self, node: nodes.Break, frame: Frame) -> None: |
| self.writeline("break", node) |
| |
| def visit_Scope(self, node: nodes.Scope, frame: Frame) -> None: |
| 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: nodes.OverlayScope, frame: Frame) -> None: |
| ctx = self.temporary_identifier() |
| self.writeline(f"{ctx} = {self.derive_context(frame)}") |
| self.writeline(f"{ctx}.vars = ") |
| 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: nodes.EvalContextModifier, frame: Frame |
| ) -> None: |
| for keyword in node.options: |
| self.writeline(f"context.eval_ctx.{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: nodes.ScopedEvalContextModifier, frame: Frame |
| ) -> None: |
| old_ctx_name = self.temporary_identifier() |
| saved_ctx = frame.eval_ctx.save() |
| self.writeline(f"{old_ctx_name} = context.eval_ctx.save()") |
| self.visit_EvalContextModifier(node, frame) |
| for child in node.body: |
| self.visit(child, frame) |
| frame.eval_ctx.revert(saved_ctx) |
| self.writeline(f"context.eval_ctx.revert({old_ctx_name})") |
