| """Parse tokens from the lexer into nodes for the compiler.""" | |
| from . import nodes | |
| from .exceptions import TemplateAssertionError | |
| from .exceptions import TemplateSyntaxError | |
| from .lexer import describe_token | |
| from .lexer import describe_token_expr | |
| _statement_keywords = frozenset( | |
| [ | |
| "for", | |
| "if", | |
| "block", | |
| "extends", | |
| "print", | |
| "macro", | |
| "include", | |
| "from", | |
| "import", | |
| "set", | |
| "with", | |
| "autoescape", | |
| ] | |
| ) | |
| _compare_operators = frozenset(["eq", "ne", "lt", "lteq", "gt", "gteq"]) | |
| _math_nodes = { | |
| "add": nodes.Add, | |
| "sub": nodes.Sub, | |
| "mul": nodes.Mul, | |
| "div": nodes.Div, | |
| "floordiv": nodes.FloorDiv, | |
| "mod": nodes.Mod, | |
| } | |
| class Parser: | |
| """This is the central parsing class Jinja uses. It's passed to | |
| extensions and can be used to parse expressions or statements. | |
| """ | |
| def __init__(self, environment, source, name=None, filename=None, state=None): | |
| self.environment = environment | |
| self.stream = environment._tokenize(source, name, filename, state) | |
| self.name = name | |
| self.filename = filename | |
| self.closed = False | |
| self.extensions = {} | |
| for extension in environment.iter_extensions(): | |
| for tag in extension.tags: | |
| self.extensions[tag] = extension.parse | |
| self._last_identifier = 0 | |
| self._tag_stack = [] | |
| self._end_token_stack = [] | |
| def fail(self, msg, lineno=None, exc=TemplateSyntaxError): | |
| """Convenience method that raises `exc` with the message, passed | |
| line number or last line number as well as the current name and | |
| filename. | |
| """ | |
| if lineno is None: | |
| lineno = self.stream.current.lineno | |
| raise exc(msg, lineno, self.name, self.filename) | |
| def _fail_ut_eof(self, name, end_token_stack, lineno): | |
| expected = [] | |
| for exprs in end_token_stack: | |
| expected.extend(map(describe_token_expr, exprs)) | |
| if end_token_stack: | |
| currently_looking = " or ".join( | |
| map(repr, map(describe_token_expr, end_token_stack[-1])) | |
| ) | |
| else: | |
| currently_looking = None | |
| if name is None: | |
| message = ["Unexpected end of template."] | |
| else: | |
| message = [f"Encountered unknown tag {name!r}."] | |
| if currently_looking: | |
| if name is not None and name in expected: | |
| message.append( | |
| "You probably made a nesting mistake. Jinja is expecting this tag," | |
| f" but currently looking for {currently_looking}." | |
| ) | |
| else: | |
| message.append( | |
| f"Jinja was looking for the following tags: {currently_looking}." | |
| ) | |
| if self._tag_stack: | |
| message.append( | |
| "The innermost block that needs to be closed is" | |
| f" {self._tag_stack[-1]!r}." | |
| ) | |
| self.fail(" ".join(message), lineno) | |
| def fail_unknown_tag(self, name, lineno=None): | |
| """Called if the parser encounters an unknown tag. Tries to fail | |
| with a human readable error message that could help to identify | |
| the problem. | |
| """ | |
| return self._fail_ut_eof(name, self._end_token_stack, lineno) | |
| def fail_eof(self, end_tokens=None, lineno=None): | |
| """Like fail_unknown_tag but for end of template situations.""" | |
| stack = list(self._end_token_stack) | |
| if end_tokens is not None: | |
| stack.append(end_tokens) | |
| return self._fail_ut_eof(None, stack, lineno) | |
| def is_tuple_end(self, extra_end_rules=None): | |
| """Are we at the end of a tuple?""" | |
| if self.stream.current.type in ("variable_end", "block_end", "rparen"): | |
| return True | |
| elif extra_end_rules is not None: | |
| return self.stream.current.test_any(extra_end_rules) | |
| return False | |
| def free_identifier(self, lineno=None): | |
| """Return a new free identifier as :class:`~jinja2.nodes.InternalName`.""" | |
| self._last_identifier += 1 | |
| rv = object.__new__(nodes.InternalName) | |
| nodes.Node.__init__(rv, f"fi{self._last_identifier}", lineno=lineno) | |
| return rv | |
| def parse_statement(self): | |
| """Parse a single statement.""" | |
| token = self.stream.current | |
| if token.type != "name": | |
| self.fail("tag name expected", token.lineno) | |
| self._tag_stack.append(token.value) | |
| pop_tag = True | |
| try: | |
| if token.value in _statement_keywords: | |
| return getattr(self, "parse_" + self.stream.current.value)() | |
| if token.value == "call": | |
| return self.parse_call_block() | |
| if token.value == "filter": | |
| return self.parse_filter_block() | |
| ext = self.extensions.get(token.value) | |
| if ext is not None: | |
| return ext(self) | |
| # did not work out, remove the token we pushed by accident | |
| # from the stack so that the unknown tag fail function can | |
| # produce a proper error message. | |
| self._tag_stack.pop() | |
| pop_tag = False | |
| self.fail_unknown_tag(token.value, token.lineno) | |
| finally: | |
| if pop_tag: | |
| self._tag_stack.pop() | |
| def parse_statements(self, end_tokens, drop_needle=False): | |
| """Parse multiple statements into a list until one of the end tokens | |
| is reached. This is used to parse the body of statements as it also | |
| parses template data if appropriate. The parser checks first if the | |
| current token is a colon and skips it if there is one. Then it checks | |
| for the block end and parses until if one of the `end_tokens` is | |
| reached. Per default the active token in the stream at the end of | |
| the call is the matched end token. If this is not wanted `drop_needle` | |
| can be set to `True` and the end token is removed. | |
| """ | |
| # the first token may be a colon for python compatibility | |
| self.stream.skip_if("colon") | |
| # in the future it would be possible to add whole code sections | |
| # by adding some sort of end of statement token and parsing those here. | |
| self.stream.expect("block_end") | |
| result = self.subparse(end_tokens) | |
| # we reached the end of the template too early, the subparser | |
| # does not check for this, so we do that now | |
| if self.stream.current.type == "eof": | |
| self.fail_eof(end_tokens) | |
| if drop_needle: | |
| next(self.stream) | |
| return result | |
| def parse_set(self): | |
| """Parse an assign statement.""" | |
| lineno = next(self.stream).lineno | |
| target = self.parse_assign_target(with_namespace=True) | |
| if self.stream.skip_if("assign"): | |
| expr = self.parse_tuple() | |
| return nodes.Assign(target, expr, lineno=lineno) | |
| filter_node = self.parse_filter(None) | |
| body = self.parse_statements(("name:endset",), drop_needle=True) | |
| return nodes.AssignBlock(target, filter_node, body, lineno=lineno) | |
| def parse_for(self): | |
| """Parse a for loop.""" | |
| lineno = self.stream.expect("name:for").lineno | |
| target = self.parse_assign_target(extra_end_rules=("name:in",)) | |
| self.stream.expect("name:in") | |
| iter = self.parse_tuple( | |
| with_condexpr=False, extra_end_rules=("name:recursive",) | |
| ) | |
| test = None | |
| if self.stream.skip_if("name:if"): | |
| test = self.parse_expression() | |
| recursive = self.stream.skip_if("name:recursive") | |
| body = self.parse_statements(("name:endfor", "name:else")) | |
| if next(self.stream).value == "endfor": | |
| else_ = [] | |
| else: | |
| else_ = self.parse_statements(("name:endfor",), drop_needle=True) | |
| return nodes.For(target, iter, body, else_, test, recursive, lineno=lineno) | |
| def parse_if(self): | |
| """Parse an if construct.""" | |
| node = result = nodes.If(lineno=self.stream.expect("name:if").lineno) | |
| while 1: | |
| node.test = self.parse_tuple(with_condexpr=False) | |
| node.body = self.parse_statements(("name:elif", "name:else", "name:endif")) | |
| node.elif_ = [] | |
| node.else_ = [] | |
| token = next(self.stream) | |
| if token.test("name:elif"): | |
| node = nodes.If(lineno=self.stream.current.lineno) | |
| result.elif_.append(node) | |
| continue | |
| elif token.test("name:else"): | |
| result.else_ = self.parse_statements(("name:endif",), drop_needle=True) | |
| break | |
| return result | |
| def parse_with(self): | |
| node = nodes.With(lineno=next(self.stream).lineno) | |
| targets = [] | |
| values = [] | |
| while self.stream.current.type != "block_end": | |
| if targets: | |
| self.stream.expect("comma") | |
| target = self.parse_assign_target() | |
| target.set_ctx("param") | |
| targets.append(target) | |
| self.stream.expect("assign") | |
| values.append(self.parse_expression()) | |
| node.targets = targets | |
| node.values = values | |
| node.body = self.parse_statements(("name:endwith",), drop_needle=True) | |
| return node | |
| def parse_autoescape(self): | |
| node = nodes.ScopedEvalContextModifier(lineno=next(self.stream).lineno) | |
| node.options = [nodes.Keyword("autoescape", self.parse_expression())] | |
| node.body = self.parse_statements(("name:endautoescape",), drop_needle=True) | |
| return nodes.Scope([node]) | |
| def parse_block(self): | |
| node = nodes.Block(lineno=next(self.stream).lineno) | |
| node.name = self.stream.expect("name").value | |
| node.scoped = self.stream.skip_if("name:scoped") | |
| # common problem people encounter when switching from django | |
| # to jinja. we do not support hyphens in block names, so let's | |
| # raise a nicer error message in that case. | |
| if self.stream.current.type == "sub": | |
| self.fail( | |
| "Block names in Jinja have to be valid Python identifiers and may not" | |
| " contain hyphens, use an underscore instead." | |
| ) | |
| node.body = self.parse_statements(("name:endblock",), drop_needle=True) | |
| self.stream.skip_if("name:" + node.name) | |
| return node | |
| def parse_extends(self): | |
| node = nodes.Extends(lineno=next(self.stream).lineno) | |
| node.template = self.parse_expression() | |
| return node | |
| def parse_import_context(self, node, default): | |
| if self.stream.current.test_any( | |
| "name:with", "name:without" | |
| ) and self.stream.look().test("name:context"): | |
| node.with_context = next(self.stream).value == "with" | |
| self.stream.skip() | |
| else: | |
| node.with_context = default | |
| return node | |
| def parse_include(self): | |
| node = nodes.Include(lineno=next(self.stream).lineno) | |
| node.template = self.parse_expression() | |
| if self.stream.current.test("name:ignore") and self.stream.look().test( | |
| "name:missing" | |
| ): | |
| node.ignore_missing = True | |
| self.stream.skip(2) | |
| else: | |
| node.ignore_missing = False | |
| return self.parse_import_context(node, True) | |
| def parse_import(self): | |
| node = nodes.Import(lineno=next(self.stream).lineno) | |
| node.template = self.parse_expression() | |
| self.stream.expect("name:as") | |
| node.target = self.parse_assign_target(name_only=True).name | |
| return self.parse_import_context(node, False) | |
| def parse_from(self): | |
| node = nodes.FromImport(lineno=next(self.stream).lineno) | |
| node.template = self.parse_expression() | |
| self.stream.expect("name:import") | |
| node.names = [] | |
| def parse_context(): | |
| if self.stream.current.value in ( | |
| "with", | |
| "without", | |
| ) and self.stream.look().test("name:context"): | |
| node.with_context = next(self.stream).value == "with" | |
| self.stream.skip() | |
| return True | |
| return False | |
| while 1: | |
| if node.names: | |
| self.stream.expect("comma") | |
| if self.stream.current.type == "name": | |
| if parse_context(): | |
| break | |
| target = self.parse_assign_target(name_only=True) | |
| if target.name.startswith("_"): | |
| self.fail( | |
| "names starting with an underline can not be imported", | |
| target.lineno, | |
| exc=TemplateAssertionError, | |
| ) | |
| if self.stream.skip_if("name:as"): | |
| alias = self.parse_assign_target(name_only=True) | |
| node.names.append((target.name, alias.name)) | |
| else: | |
| node.names.append(target.name) | |
| if parse_context() or self.stream.current.type != "comma": | |
| break | |
| else: | |
| self.stream.expect("name") | |
| if not hasattr(node, "with_context"): | |
| node.with_context = False | |
| return node | |
| def parse_signature(self, node): | |
| node.args = args = [] | |
| node.defaults = defaults = [] | |
| self.stream.expect("lparen") | |
| while self.stream.current.type != "rparen": | |
| if args: | |
| self.stream.expect("comma") | |
| arg = self.parse_assign_target(name_only=True) | |
| arg.set_ctx("param") | |
| if self.stream.skip_if("assign"): | |
| defaults.append(self.parse_expression()) | |
| elif defaults: | |
| self.fail("non-default argument follows default argument") | |
| args.append(arg) | |
| self.stream.expect("rparen") | |
| def parse_call_block(self): | |
| node = nodes.CallBlock(lineno=next(self.stream).lineno) | |
| if self.stream.current.type == "lparen": | |
| self.parse_signature(node) | |
| else: | |
| node.args = [] | |
| node.defaults = [] | |
| node.call = self.parse_expression() | |
| if not isinstance(node.call, nodes.Call): | |
| self.fail("expected call", node.lineno) | |
| node.body = self.parse_statements(("name:endcall",), drop_needle=True) | |
| return node | |
| def parse_filter_block(self): | |
| node = nodes.FilterBlock(lineno=next(self.stream).lineno) | |
| node.filter = self.parse_filter(None, start_inline=True) | |
| node.body = self.parse_statements(("name:endfilter",), drop_needle=True) | |
| return node | |
| def parse_macro(self): | |
| node = nodes.Macro(lineno=next(self.stream).lineno) | |
| node.name = self.parse_assign_target(name_only=True).name | |
| self.parse_signature(node) | |
| node.body = self.parse_statements(("name:endmacro",), drop_needle=True) | |
| return node | |
| def parse_print(self): | |
| node = nodes.Output(lineno=next(self.stream).lineno) | |
| node.nodes = [] | |
| while self.stream.current.type != "block_end": | |
| if node.nodes: | |
| self.stream.expect("comma") | |
| node.nodes.append(self.parse_expression()) | |
| return node | |
| def parse_assign_target( | |
| self, | |
| with_tuple=True, | |
| name_only=False, | |
| extra_end_rules=None, | |
| with_namespace=False, | |
| ): | |
| """Parse an assignment target. As Jinja allows assignments to | |
| tuples, this function can parse all allowed assignment targets. Per | |
| default assignments to tuples are parsed, that can be disable however | |
| by setting `with_tuple` to `False`. If only assignments to names are | |
| wanted `name_only` can be set to `True`. The `extra_end_rules` | |
| parameter is forwarded to the tuple parsing function. If | |
| `with_namespace` is enabled, a namespace assignment may be parsed. | |
| """ | |
| if with_namespace and self.stream.look().type == "dot": | |
| token = self.stream.expect("name") | |
| next(self.stream) # dot | |
| attr = self.stream.expect("name") | |
| target = nodes.NSRef(token.value, attr.value, lineno=token.lineno) | |
| elif name_only: | |
| token = self.stream.expect("name") | |
| target = nodes.Name(token.value, "store", lineno=token.lineno) | |
| else: | |
| if with_tuple: | |
| target = self.parse_tuple( | |
| simplified=True, extra_end_rules=extra_end_rules | |
| ) | |
| else: | |
| target = self.parse_primary() | |
| target.set_ctx("store") | |
| if not target.can_assign(): | |
| self.fail( | |
| f"can't assign to {target.__class__.__name__.lower()!r}", target.lineno | |
| ) | |
| return target | |
| def parse_expression(self, with_condexpr=True): | |
| """Parse an expression. Per default all expressions are parsed, if | |
| the optional `with_condexpr` parameter is set to `False` conditional | |
| expressions are not parsed. | |
| """ | |
| if with_condexpr: | |
| return self.parse_condexpr() | |
| return self.parse_or() | |
| def parse_condexpr(self): | |
| lineno = self.stream.current.lineno | |
| expr1 = self.parse_or() | |
| while self.stream.skip_if("name:if"): | |
| expr2 = self.parse_or() | |
| if self.stream.skip_if("name:else"): | |
| expr3 = self.parse_condexpr() | |
| else: | |
| expr3 = None | |
| expr1 = nodes.CondExpr(expr2, expr1, expr3, lineno=lineno) | |
| lineno = self.stream.current.lineno | |
| return expr1 | |
| def parse_or(self): | |
| lineno = self.stream.current.lineno | |
| left = self.parse_and() | |
| while self.stream.skip_if("name:or"): | |
| right = self.parse_and() | |
| left = nodes.Or(left, right, lineno=lineno) | |
| lineno = self.stream.current.lineno | |
| return left | |
| def parse_and(self): | |
| lineno = self.stream.current.lineno | |
| left = self.parse_not() | |
| while self.stream.skip_if("name:and"): | |
| right = self.parse_not() | |
| left = nodes.And(left, right, lineno=lineno) | |
| lineno = self.stream.current.lineno | |
| return left | |
| def parse_not(self): | |
| if self.stream.current.test("name:not"): | |
| lineno = next(self.stream).lineno | |
| return nodes.Not(self.parse_not(), lineno=lineno) | |
| return self.parse_compare() | |
| def parse_compare(self): | |
| lineno = self.stream.current.lineno | |
| expr = self.parse_math1() | |
| ops = [] | |
| while 1: | |
| token_type = self.stream.current.type | |
| if token_type in _compare_operators: | |
| next(self.stream) | |
| ops.append(nodes.Operand(token_type, self.parse_math1())) | |
| elif self.stream.skip_if("name:in"): | |
| ops.append(nodes.Operand("in", self.parse_math1())) | |
| elif self.stream.current.test("name:not") and self.stream.look().test( | |
| "name:in" | |
| ): | |
| self.stream.skip(2) | |
| ops.append(nodes.Operand("notin", self.parse_math1())) | |
| else: | |
| break | |
| lineno = self.stream.current.lineno | |
| if not ops: | |
| return expr | |
| return nodes.Compare(expr, ops, lineno=lineno) | |
| def parse_math1(self): | |
| lineno = self.stream.current.lineno | |
| left = self.parse_concat() | |
| while self.stream.current.type in ("add", "sub"): | |
| cls = _math_nodes[self.stream.current.type] | |
| next(self.stream) | |
| right = self.parse_concat() | |
| left = cls(left, right, lineno=lineno) | |
| lineno = self.stream.current.lineno | |
| return left | |
| def parse_concat(self): | |
| lineno = self.stream.current.lineno | |
| args = [self.parse_math2()] | |
| while self.stream.current.type == "tilde": | |
| next(self.stream) | |
| args.append(self.parse_math2()) | |
| if len(args) == 1: | |
| return args[0] | |
| return nodes.Concat(args, lineno=lineno) | |
| def parse_math2(self): | |
| lineno = self.stream.current.lineno | |
| left = self.parse_pow() | |
| while self.stream.current.type in ("mul", "div", "floordiv", "mod"): | |
| cls = _math_nodes[self.stream.current.type] | |
| next(self.stream) | |
| right = self.parse_pow() | |
| left = cls(left, right, lineno=lineno) | |
| lineno = self.stream.current.lineno | |
| return left | |
| def parse_pow(self): | |
| lineno = self.stream.current.lineno | |
| left = self.parse_unary() | |
| while self.stream.current.type == "pow": | |
| next(self.stream) | |
| right = self.parse_unary() | |
| left = nodes.Pow(left, right, lineno=lineno) | |
| lineno = self.stream.current.lineno | |
| return left | |
| def parse_unary(self, with_filter=True): | |
| token_type = self.stream.current.type | |
| lineno = self.stream.current.lineno | |
| if token_type == "sub": | |
| next(self.stream) | |
| node = nodes.Neg(self.parse_unary(False), lineno=lineno) | |
| elif token_type == "add": | |
| next(self.stream) | |
| node = nodes.Pos(self.parse_unary(False), lineno=lineno) | |
| else: | |
| node = self.parse_primary() | |
| node = self.parse_postfix(node) | |
| if with_filter: | |
| node = self.parse_filter_expr(node) | |
| return node | |
| def parse_primary(self): | |
| token = self.stream.current | |
| if token.type == "name": | |
| if token.value in ("true", "false", "True", "False"): | |
| node = nodes.Const(token.value in ("true", "True"), lineno=token.lineno) | |
| elif token.value in ("none", "None"): | |
| node = nodes.Const(None, lineno=token.lineno) | |
| else: | |
| node = nodes.Name(token.value, "load", lineno=token.lineno) | |
| next(self.stream) | |
| elif token.type == "string": | |
| next(self.stream) | |
| buf = [token.value] | |
| lineno = token.lineno | |
| while self.stream.current.type == "string": | |
| buf.append(self.stream.current.value) | |
| next(self.stream) | |
| node = nodes.Const("".join(buf), lineno=lineno) | |
| elif token.type in ("integer", "float"): | |
| next(self.stream) | |
| node = nodes.Const(token.value, lineno=token.lineno) | |
| elif token.type == "lparen": | |
| next(self.stream) | |
| node = self.parse_tuple(explicit_parentheses=True) | |
| self.stream.expect("rparen") | |
| elif token.type == "lbracket": | |
| node = self.parse_list() | |
| elif token.type == "lbrace": | |
| node = self.parse_dict() | |
| else: | |
| self.fail(f"unexpected {describe_token(token)!r}", token.lineno) | |
| return node | |
| def parse_tuple( | |
| self, | |
| simplified=False, | |
| with_condexpr=True, | |
| extra_end_rules=None, | |
| explicit_parentheses=False, | |
| ): | |
| """Works like `parse_expression` but if multiple expressions are | |
| delimited by a comma a :class:`~jinja2.nodes.Tuple` node is created. | |
| This method could also return a regular expression instead of a tuple | |
| if no commas where found. | |
| The default parsing mode is a full tuple. If `simplified` is `True` | |
| only names and literals are parsed. The `no_condexpr` parameter is | |
| forwarded to :meth:`parse_expression`. | |
| Because tuples do not require delimiters and may end in a bogus comma | |
| an extra hint is needed that marks the end of a tuple. For example | |
| for loops support tuples between `for` and `in`. In that case the | |
| `extra_end_rules` is set to ``['name:in']``. | |
| `explicit_parentheses` is true if the parsing was triggered by an | |
| expression in parentheses. This is used to figure out if an empty | |
| tuple is a valid expression or not. | |
| """ | |
| lineno = self.stream.current.lineno | |
| if simplified: | |
| parse = self.parse_primary | |
| elif with_condexpr: | |
| parse = self.parse_expression | |
| else: | |
| def parse(): | |
| return self.parse_expression(with_condexpr=False) | |
| args = [] | |
| is_tuple = False | |
| while 1: | |
| if args: | |
| self.stream.expect("comma") | |
| if self.is_tuple_end(extra_end_rules): | |
| break | |
| args.append(parse()) | |
| if self.stream.current.type == "comma": | |
| is_tuple = True | |
| else: | |
| break | |
| lineno = self.stream.current.lineno | |
| if not is_tuple: | |
| if args: | |
| return args[0] | |
| # if we don't have explicit parentheses, an empty tuple is | |
| # not a valid expression. This would mean nothing (literally | |
| # nothing) in the spot of an expression would be an empty | |
| # tuple. | |
| if not explicit_parentheses: | |
| self.fail( | |
| "Expected an expression," | |
| f" got {describe_token(self.stream.current)!r}" | |
| ) | |
| return nodes.Tuple(args, "load", lineno=lineno) | |
| def parse_list(self): | |
| token = self.stream.expect("lbracket") | |
| items = [] | |
| while self.stream.current.type != "rbracket": | |
| if items: | |
| self.stream.expect("comma") | |
| if self.stream.current.type == "rbracket": | |
| break | |
| items.append(self.parse_expression()) | |
| self.stream.expect("rbracket") | |
| return nodes.List(items, lineno=token.lineno) | |
| def parse_dict(self): | |
| token = self.stream.expect("lbrace") | |
| items = [] | |
| while self.stream.current.type != "rbrace": | |
| if items: | |
| self.stream.expect("comma") | |
| if self.stream.current.type == "rbrace": | |
| break | |
| key = self.parse_expression() | |
| self.stream.expect("colon") | |
| value = self.parse_expression() | |
| items.append(nodes.Pair(key, value, lineno=key.lineno)) | |
| self.stream.expect("rbrace") | |
| return nodes.Dict(items, lineno=token.lineno) | |
| def parse_postfix(self, node): | |
| while 1: | |
| token_type = self.stream.current.type | |
| if token_type == "dot" or token_type == "lbracket": | |
| node = self.parse_subscript(node) | |
| # calls are valid both after postfix expressions (getattr | |
| # and getitem) as well as filters and tests | |
| elif token_type == "lparen": | |
| node = self.parse_call(node) | |
| else: | |
| break | |
| return node | |
| def parse_filter_expr(self, node): | |
| while 1: | |
| token_type = self.stream.current.type | |
| if token_type == "pipe": | |
| node = self.parse_filter(node) | |
| elif token_type == "name" and self.stream.current.value == "is": | |
| node = self.parse_test(node) | |
| # calls are valid both after postfix expressions (getattr | |
| # and getitem) as well as filters and tests | |
| elif token_type == "lparen": | |
| node = self.parse_call(node) | |
| else: | |
| break | |
| return node | |
| def parse_subscript(self, node): | |
| token = next(self.stream) | |
| if token.type == "dot": | |
| attr_token = self.stream.current | |
| next(self.stream) | |
| if attr_token.type == "name": | |
| return nodes.Getattr( | |
| node, attr_token.value, "load", lineno=token.lineno | |
| ) | |
| elif attr_token.type != "integer": | |
| self.fail("expected name or number", attr_token.lineno) | |
| arg = nodes.Const(attr_token.value, lineno=attr_token.lineno) | |
| return nodes.Getitem(node, arg, "load", lineno=token.lineno) | |
| if token.type == "lbracket": | |
| args = [] | |
| while self.stream.current.type != "rbracket": | |
| if args: | |
| self.stream.expect("comma") | |
| args.append(self.parse_subscribed()) | |
| self.stream.expect("rbracket") | |
| if len(args) == 1: | |
| arg = args[0] | |
| else: | |
| arg = nodes.Tuple(args, "load", lineno=token.lineno) | |
| return nodes.Getitem(node, arg, "load", lineno=token.lineno) | |
| self.fail("expected subscript expression", token.lineno) | |
| def parse_subscribed(self): | |
| lineno = self.stream.current.lineno | |
| if self.stream.current.type == "colon": | |
| next(self.stream) | |
| args = [None] | |
| else: | |
| node = self.parse_expression() | |
| if self.stream.current.type != "colon": | |
| return node | |
| next(self.stream) | |
| args = [node] | |
| if self.stream.current.type == "colon": | |
| args.append(None) | |
| elif self.stream.current.type not in ("rbracket", "comma"): | |
| args.append(self.parse_expression()) | |
| else: | |
| args.append(None) | |
| if self.stream.current.type == "colon": | |
| next(self.stream) | |
| if self.stream.current.type not in ("rbracket", "comma"): | |
| args.append(self.parse_expression()) | |
| else: | |
| args.append(None) | |
| else: | |
| args.append(None) | |
| return nodes.Slice(lineno=lineno, *args) | |
| def parse_call(self, node): | |
| token = self.stream.expect("lparen") | |
| args = [] | |
| kwargs = [] | |
| dyn_args = dyn_kwargs = None | |
| require_comma = False | |
| def ensure(expr): | |
| if not expr: | |
| self.fail("invalid syntax for function call expression", token.lineno) | |
| while self.stream.current.type != "rparen": | |
| if require_comma: | |
| self.stream.expect("comma") | |
| # support for trailing comma | |
| if self.stream.current.type == "rparen": | |
| break | |
| if self.stream.current.type == "mul": | |
| ensure(dyn_args is None and dyn_kwargs is None) | |
| next(self.stream) | |
| dyn_args = self.parse_expression() | |
| elif self.stream.current.type == "pow": | |
| ensure(dyn_kwargs is None) | |
| next(self.stream) | |
| dyn_kwargs = self.parse_expression() | |
| else: | |
| if ( | |
| self.stream.current.type == "name" | |
| and self.stream.look().type == "assign" | |
| ): | |
| # Parsing a kwarg | |
| ensure(dyn_kwargs is None) | |
| key = self.stream.current.value | |
| self.stream.skip(2) | |
| value = self.parse_expression() | |
| kwargs.append(nodes.Keyword(key, value, lineno=value.lineno)) | |
| else: | |
| # Parsing an arg | |
| ensure(dyn_args is None and dyn_kwargs is None and not kwargs) | |
| args.append(self.parse_expression()) | |
| require_comma = True | |
| self.stream.expect("rparen") | |
| if node is None: | |
| return args, kwargs, dyn_args, dyn_kwargs | |
| return nodes.Call(node, args, kwargs, dyn_args, dyn_kwargs, lineno=token.lineno) | |
| def parse_filter(self, node, start_inline=False): | |
| while self.stream.current.type == "pipe" or start_inline: | |
| if not start_inline: | |
| next(self.stream) | |
| token = self.stream.expect("name") | |
| name = token.value | |
| while self.stream.current.type == "dot": | |
| next(self.stream) | |
| name += "." + self.stream.expect("name").value | |
| if self.stream.current.type == "lparen": | |
| args, kwargs, dyn_args, dyn_kwargs = self.parse_call(None) | |
| else: | |
| args = [] | |
| kwargs = [] | |
| dyn_args = dyn_kwargs = None | |
| node = nodes.Filter( | |
| node, name, args, kwargs, dyn_args, dyn_kwargs, lineno=token.lineno | |
| ) | |
| start_inline = False | |
| return node | |
| def parse_test(self, node): | |
| token = next(self.stream) | |
| if self.stream.current.test("name:not"): | |
| next(self.stream) | |
| negated = True | |
| else: | |
| negated = False | |
| name = self.stream.expect("name").value | |
| while self.stream.current.type == "dot": | |
| next(self.stream) | |
| name += "." + self.stream.expect("name").value | |
| dyn_args = dyn_kwargs = None | |
| kwargs = [] | |
| if self.stream.current.type == "lparen": | |
| args, kwargs, dyn_args, dyn_kwargs = self.parse_call(None) | |
| elif self.stream.current.type in ( | |
| "name", | |
| "string", | |
| "integer", | |
| "float", | |
| "lparen", | |
| "lbracket", | |
| "lbrace", | |
| ) and not self.stream.current.test_any("name:else", "name:or", "name:and"): | |
| if self.stream.current.test("name:is"): | |
| self.fail("You cannot chain multiple tests with is") | |
| arg_node = self.parse_primary() | |
| arg_node = self.parse_postfix(arg_node) | |
| args = [arg_node] | |
| else: | |
| args = [] | |
| node = nodes.Test( | |
| node, name, args, kwargs, dyn_args, dyn_kwargs, lineno=token.lineno | |
| ) | |
| if negated: | |
| node = nodes.Not(node, lineno=token.lineno) | |
| return node | |
| def subparse(self, end_tokens=None): | |
| body = [] | |
| data_buffer = [] | |
| add_data = data_buffer.append | |
| if end_tokens is not None: | |
| self._end_token_stack.append(end_tokens) | |
| def flush_data(): | |
| if data_buffer: | |
| lineno = data_buffer[0].lineno | |
| body.append(nodes.Output(data_buffer[:], lineno=lineno)) | |
| del data_buffer[:] | |
| try: | |
| while self.stream: | |
| token = self.stream.current | |
| if token.type == "data": | |
| if token.value: | |
| add_data(nodes.TemplateData(token.value, lineno=token.lineno)) | |
| next(self.stream) | |
| elif token.type == "variable_begin": | |
| next(self.stream) | |
| add_data(self.parse_tuple(with_condexpr=True)) | |
| self.stream.expect("variable_end") | |
| elif token.type == "block_begin": | |
| flush_data() | |
| next(self.stream) | |
| if end_tokens is not None and self.stream.current.test_any( | |
| *end_tokens | |
| ): | |
| return body | |
| rv = self.parse_statement() | |
| if isinstance(rv, list): | |
| body.extend(rv) | |
| else: | |
| body.append(rv) | |
| self.stream.expect("block_end") | |
| else: | |
| raise AssertionError("internal parsing error") | |
| flush_data() | |
| finally: | |
| if end_tokens is not None: | |
| self._end_token_stack.pop() | |
| return body | |
| def parse(self): | |
| """Parse the whole template into a `Template` node.""" | |
| result = nodes.Template(self.subparse(), lineno=1) | |
| result.set_environment(self.environment) | |
| return result |