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edit//Qwen3-TTS-test//.venv//Lib//site-packages//jinja2//lexer.py

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+"""Implements a Jinja / Python combination lexer. The ``Lexer`` class
+is used to do some preprocessing. It filters out invalid operators like
+the bitshift operators we don't allow in templates. It separates
+template code and python code in expressions.
+"""
+
+import re
+import typing as t
+from ast import literal_eval
+from collections import deque
+from sys import intern
+
+from ._identifier import pattern as name_re
+from .exceptions import TemplateSyntaxError
+from .utils import LRUCache
+
+if t.TYPE_CHECKING:
+    import typing_extensions as te
+
+    from .environment import Environment
+
+# cache for the lexers. Exists in order to be able to have multiple
+# environments with the same lexer
+_lexer_cache: t.MutableMapping[t.Tuple, "Lexer"] = LRUCache(50)  # type: ignore
+
+# static regular expressions
+whitespace_re = re.compile(r"\s+")
+newline_re = re.compile(r"(\r\n|\r|\n)")
+string_re = re.compile(
+    r"('([^'\\]*(?:\\.[^'\\]*)*)'" r'|"([^"\\]*(?:\\.[^"\\]*)*)")', re.S
+)
+integer_re = re.compile(
+    r"""
+    (
+        0b(_?[0-1])+ # binary
+    |
+        0o(_?[0-7])+ # octal
+    |
+        0x(_?[\da-f])+ # hex
+    |
+        [1-9](_?\d)* # decimal
+    |
+        0(_?0)* # decimal zero
+    )
+    """,
+    re.IGNORECASE | re.VERBOSE,
+)
+float_re = re.compile(
+    r"""
+    (?<!\.)  # doesn't start with a .
+    (\d+_)*\d+  # digits, possibly _ separated
+    (
+        (\.(\d+_)*\d+)?  # optional fractional part
+        e[+\-]?(\d+_)*\d+  # exponent part
+    |
+        \.(\d+_)*\d+  # required fractional part
+    )
+    """,
+    re.IGNORECASE | re.VERBOSE,
+)
+
+# internal the tokens and keep references to them
+TOKEN_ADD = intern("add")
+TOKEN_ASSIGN = intern("assign")
+TOKEN_COLON = intern("colon")
+TOKEN_COMMA = intern("comma")
+TOKEN_DIV = intern("div")
+TOKEN_DOT = intern("dot")
+TOKEN_EQ = intern("eq")
+TOKEN_FLOORDIV = intern("floordiv")
+TOKEN_GT = intern("gt")
+TOKEN_GTEQ = intern("gteq")
+TOKEN_LBRACE = intern("lbrace")
+TOKEN_LBRACKET = intern("lbracket")
+TOKEN_LPAREN = intern("lparen")
+TOKEN_LT = intern("lt")
+TOKEN_LTEQ = intern("lteq")
+TOKEN_MOD = intern("mod")
+TOKEN_MUL = intern("mul")
+TOKEN_NE = intern("ne")
+TOKEN_PIPE = intern("pipe")
+TOKEN_POW = intern("pow")
+TOKEN_RBRACE = intern("rbrace")
+TOKEN_RBRACKET = intern("rbracket")
+TOKEN_RPAREN = intern("rparen")
+TOKEN_SEMICOLON = intern("semicolon")
+TOKEN_SUB = intern("sub")
+TOKEN_TILDE = intern("tilde")
+TOKEN_WHITESPACE = intern("whitespace")
+TOKEN_FLOAT = intern("float")
+TOKEN_INTEGER = intern("integer")
+TOKEN_NAME = intern("name")
+TOKEN_STRING = intern("string")
+TOKEN_OPERATOR = intern("operator")
+TOKEN_BLOCK_BEGIN = intern("block_begin")
+TOKEN_BLOCK_END = intern("block_end")
+TOKEN_VARIABLE_BEGIN = intern("variable_begin")
+TOKEN_VARIABLE_END = intern("variable_end")
+TOKEN_RAW_BEGIN = intern("raw_begin")
+TOKEN_RAW_END = intern("raw_end")
+TOKEN_COMMENT_BEGIN = intern("comment_begin")
+TOKEN_COMMENT_END = intern("comment_end")
+TOKEN_COMMENT = intern("comment")
+TOKEN_LINESTATEMENT_BEGIN = intern("linestatement_begin")
+TOKEN_LINESTATEMENT_END = intern("linestatement_end")
+TOKEN_LINECOMMENT_BEGIN = intern("linecomment_begin")
+TOKEN_LINECOMMENT_END = intern("linecomment_end")
+TOKEN_LINECOMMENT = intern("linecomment")
+TOKEN_DATA = intern("data")
+TOKEN_INITIAL = intern("initial")
+TOKEN_EOF = intern("eof")
+
+# bind operators to token types
+operators = {
+    "+": TOKEN_ADD,
+    "-": TOKEN_SUB,
+    "/": TOKEN_DIV,
+    "//": TOKEN_FLOORDIV,
+    "*": TOKEN_MUL,
+    "%": TOKEN_MOD,
+    "**": TOKEN_POW,
+    "~": TOKEN_TILDE,
+    "[": TOKEN_LBRACKET,
+    "]": TOKEN_RBRACKET,
+    "(": TOKEN_LPAREN,
+    ")": TOKEN_RPAREN,
+    "{": TOKEN_LBRACE,
+    "}": TOKEN_RBRACE,
+    "==": TOKEN_EQ,
+    "!=": TOKEN_NE,
+    ">": TOKEN_GT,
+    ">=": TOKEN_GTEQ,
+    "<": TOKEN_LT,
+    "<=": TOKEN_LTEQ,
+    "=": TOKEN_ASSIGN,
+    ".": TOKEN_DOT,
+    ":": TOKEN_COLON,
+    "|": TOKEN_PIPE,
+    ",": TOKEN_COMMA,
+    ";": TOKEN_SEMICOLON,
+}
+
+reverse_operators = {v: k for k, v in operators.items()}
+assert len(operators) == len(reverse_operators), "operators dropped"
+operator_re = re.compile(
+    f"({'|'.join(re.escape(x) for x in sorted(operators, key=lambda x: -len(x)))})"
+)
+
+ignored_tokens = frozenset(
+    [
+        TOKEN_COMMENT_BEGIN,
+        TOKEN_COMMENT,
+        TOKEN_COMMENT_END,
+        TOKEN_WHITESPACE,
+        TOKEN_LINECOMMENT_BEGIN,
+        TOKEN_LINECOMMENT_END,
+        TOKEN_LINECOMMENT,
+    ]
+)
+ignore_if_empty = frozenset(
+    [TOKEN_WHITESPACE, TOKEN_DATA, TOKEN_COMMENT, TOKEN_LINECOMMENT]
+)
+
+
+def _describe_token_type(token_type: str) -> str:
+    if token_type in reverse_operators:
+        return reverse_operators[token_type]
+
+    return {
+        TOKEN_COMMENT_BEGIN: "begin of comment",
+        TOKEN_COMMENT_END: "end of comment",
+        TOKEN_COMMENT: "comment",
+        TOKEN_LINECOMMENT: "comment",
+        TOKEN_BLOCK_BEGIN: "begin of statement block",
+        TOKEN_BLOCK_END: "end of statement block",
+        TOKEN_VARIABLE_BEGIN: "begin of print statement",
+        TOKEN_VARIABLE_END: "end of print statement",
+        TOKEN_LINESTATEMENT_BEGIN: "begin of line statement",
+        TOKEN_LINESTATEMENT_END: "end of line statement",
+        TOKEN_DATA: "template data / text",
+        TOKEN_EOF: "end of template",
+    }.get(token_type, token_type)
+
+
+def describe_token(token: "Token") -> str:
+    """Returns a description of the token."""
+    if token.type == TOKEN_NAME:
+        return token.value
+
+    return _describe_token_type(token.type)
+
+
+def describe_token_expr(expr: str) -> str:
+    """Like `describe_token` but for token expressions."""
+    if ":" in expr:
+        type, value = expr.split(":", 1)
+
+        if type == TOKEN_NAME:
+            return value
+    else:
+        type = expr
+
+    return _describe_token_type(type)
+
+
+def count_newlines(value: str) -> int:
+    """Count the number of newline characters in the string.  This is
+    useful for extensions that filter a stream.
+    """
+    return len(newline_re.findall(value))
+
+
+def compile_rules(environment: "Environment") -> t.List[t.Tuple[str, str]]:
+    """Compiles all the rules from the environment into a list of rules."""
+    e = re.escape
+    rules = [
+        (
+            len(environment.comment_start_string),
+            TOKEN_COMMENT_BEGIN,
+            e(environment.comment_start_string),
+        ),
+        (
+            len(environment.block_start_string),
+            TOKEN_BLOCK_BEGIN,
+            e(environment.block_start_string),
+        ),
+        (
+            len(environment.variable_start_string),
+            TOKEN_VARIABLE_BEGIN,
+            e(environment.variable_start_string),
+        ),
+    ]
+
+    if environment.line_statement_prefix is not None:
+        rules.append(
+            (
+                len(environment.line_statement_prefix),
+                TOKEN_LINESTATEMENT_BEGIN,
+                r"^[ \t\v]*" + e(environment.line_statement_prefix),
+            )
+        )
+    if environment.line_comment_prefix is not None:
+        rules.append(
+            (
+                len(environment.line_comment_prefix),
+                TOKEN_LINECOMMENT_BEGIN,
+                r"(?:^|(?<=\S))[^\S\r\n]*" + e(environment.line_comment_prefix),
+            )
+        )
+
+    return [x[1:] for x in sorted(rules, reverse=True)]
+
+
+class Failure:
+    """Class that raises a `TemplateSyntaxError` if called.
+    Used by the `Lexer` to specify known errors.
+    """
+
+    def __init__(
+        self, message: str, cls: t.Type[TemplateSyntaxError] = TemplateSyntaxError
+    ) -> None:
+        self.message = message
+        self.error_class = cls
+
+    def __call__(self, lineno: int, filename: t.Optional[str]) -> "te.NoReturn":
+        raise self.error_class(self.message, lineno, filename)
+
+
+class Token(t.NamedTuple):
+    lineno: int
+    type: str
+    value: str
+
+    def __str__(self) -> str:
+        return describe_token(self)
+
+    def test(self, expr: str) -> bool:
+        """Test a token against a token expression.  This can either be a
+        token type or ``'token_type:token_value'``.  This can only test
+        against string values and types.
+        """
+        # here we do a regular string equality check as test_any is usually
+        # passed an iterable of not interned strings.
+        if self.type == expr:
+            return True
+
+        if ":" in expr:
+            return expr.split(":", 1) == [self.type, self.value]
+
+        return False
+
+    def test_any(self, *iterable: str) -> bool:
+        """Test against multiple token expressions."""
+        return any(self.test(expr) for expr in iterable)
+
+
+class TokenStreamIterator:
+    """The iterator for tokenstreams.  Iterate over the stream
+    until the eof token is reached.
+    """
+
+    def __init__(self, stream: "TokenStream") -> None:
+        self.stream = stream
+
+    def __iter__(self) -> "TokenStreamIterator":
+        return self
+
+    def __next__(self) -> Token:
+        token = self.stream.current
+
+        if token.type is TOKEN_EOF:
+            self.stream.close()
+            raise StopIteration
+
+        next(self.stream)
+        return token
+
+
+class TokenStream:
+    """A token stream is an iterable that yields :class:`Token`\\s.  The
+    parser however does not iterate over it but calls :meth:`next` to go
+    one token ahead.  The current active token is stored as :attr:`current`.
+    """
+
+    def __init__(
+        self,
+        generator: t.Iterable[Token],
+        name: t.Optional[str],
+        filename: t.Optional[str],
+    ):
+        self._iter = iter(generator)
+        self._pushed: te.Deque[Token] = deque()
+        self.name = name
+        self.filename = filename
+        self.closed = False
+        self.current = Token(1, TOKEN_INITIAL, "")
+        next(self)
+
+    def __iter__(self) -> TokenStreamIterator:
+        return TokenStreamIterator(self)
+
+    def __bool__(self) -> bool:
+        return bool(self._pushed) or self.current.type is not TOKEN_EOF
+
+    @property
+    def eos(self) -> bool:
+        """Are we at the end of the stream?"""
+        return not self
+
+    def push(self, token: Token) -> None:
+        """Push a token back to the stream."""
+        self._pushed.append(token)
+
+    def look(self) -> Token:
+        """Look at the next token."""
+        old_token = next(self)
+        result = self.current
+        self.push(result)
+        self.current = old_token
+        return result
+
+    def skip(self, n: int = 1) -> None:
+        """Got n tokens ahead."""
+        for _ in range(n):
+            next(self)
+
+    def next_if(self, expr: str) -> t.Optional[Token]:
+        """Perform the token test and return the token if it matched.
+        Otherwise the return value is `None`.
+        """
+        if self.current.test(expr):
+            return next(self)
+
+        return None
+
+    def skip_if(self, expr: str) -> bool:
+        """Like :meth:`next_if` but only returns `True` or `False`."""
+        return self.next_if(expr) is not None
+
+    def __next__(self) -> Token:
+        """Go one token ahead and return the old one.
+
+        Use the built-in :func:`next` instead of calling this directly.
+        """
+        rv = self.current
+
+        if self._pushed:
+            self.current = self._pushed.popleft()
+        elif self.current.type is not TOKEN_EOF:
+            try:
+                self.current = next(self._iter)
+            except StopIteration:
+                self.close()
+
+        return rv
+
+    def close(self) -> None:
+        """Close the stream."""
+        self.current = Token(self.current.lineno, TOKEN_EOF, "")
+        self._iter = iter(())
+        self.closed = True
+
+    def expect(self, expr: str) -> Token:
+        """Expect a given token type and return it.  This accepts the same
+        argument as :meth:`jinja2.lexer.Token.test`.
+        """
+        if not self.current.test(expr):
+            expr = describe_token_expr(expr)
+
+            if self.current.type is TOKEN_EOF:
+                raise TemplateSyntaxError(
+                    f"unexpected end of template, expected {expr!r}.",
+                    self.current.lineno,
+                    self.name,
+                    self.filename,
+                )
+
+            raise TemplateSyntaxError(
+                f"expected token {expr!r}, got {describe_token(self.current)!r}",
+                self.current.lineno,
+                self.name,
+                self.filename,
+            )
+
+        return next(self)
+
+
+def get_lexer(environment: "Environment") -> "Lexer":
+    """Return a lexer which is probably cached."""
+    key = (
+        environment.block_start_string,
+        environment.block_end_string,
+        environment.variable_start_string,
+        environment.variable_end_string,
+        environment.comment_start_string,
+        environment.comment_end_string,
+        environment.line_statement_prefix,
+        environment.line_comment_prefix,
+        environment.trim_blocks,
+        environment.lstrip_blocks,
+        environment.newline_sequence,
+        environment.keep_trailing_newline,
+    )
+    lexer = _lexer_cache.get(key)
+
+    if lexer is None:
+        _lexer_cache[key] = lexer = Lexer(environment)
+
+    return lexer
+
+
+class OptionalLStrip(tuple):  # type: ignore[type-arg]
+    """A special tuple for marking a point in the state that can have
+    lstrip applied.
+    """
+
+    __slots__ = ()
+
+    # Even though it looks like a no-op, creating instances fails
+    # without this.
+    def __new__(cls, *members, **kwargs):  # type: ignore
+        return super().__new__(cls, members)
+
+
+class _Rule(t.NamedTuple):
+    pattern: t.Pattern[str]
+    tokens: t.Union[str, t.Tuple[str, ...], t.Tuple[Failure]]
+    command: t.Optional[str]
+
+
+class Lexer:
+    """Class that implements a lexer for a given environment. Automatically
+    created by the environment class, usually you don't have to do that.
+
+    Note that the lexer is not automatically bound to an environment.
+    Multiple environments can share the same lexer.
+    """
+
+    def __init__(self, environment: "Environment") -> None:
+        # shortcuts
+        e = re.escape
+
+        def c(x: str) -> t.Pattern[str]:
+            return re.compile(x, re.M | re.S)
+
+        # lexing rules for tags
+        tag_rules: t.List[_Rule] = [
+            _Rule(whitespace_re, TOKEN_WHITESPACE, None),
+            _Rule(float_re, TOKEN_FLOAT, None),
+            _Rule(integer_re, TOKEN_INTEGER, None),
+            _Rule(name_re, TOKEN_NAME, None),
+            _Rule(string_re, TOKEN_STRING, None),
+            _Rule(operator_re, TOKEN_OPERATOR, None),
+        ]
+
+        # assemble the root lexing rule. because "|" is ungreedy
+        # we have to sort by length so that the lexer continues working
+        # as expected when we have parsing rules like <% for block and
+        # <%= for variables. (if someone wants asp like syntax)
+        # variables are just part of the rules if variable processing
+        # is required.
+        root_tag_rules = compile_rules(environment)
+
+        block_start_re = e(environment.block_start_string)
+        block_end_re = e(environment.block_end_string)
+        comment_end_re = e(environment.comment_end_string)
+        variable_end_re = e(environment.variable_end_string)
+
+        # block suffix if trimming is enabled
+        block_suffix_re = "\\n?" if environment.trim_blocks else ""
+
+        self.lstrip_blocks = environment.lstrip_blocks
+
+        self.newline_sequence = environment.newline_sequence
+        self.keep_trailing_newline = environment.keep_trailing_newline
+
+        root_raw_re = (
+            rf"(?P<raw_begin>{block_start_re}(\-|\+|)\s*raw\s*"
+            rf"(?:\-{block_end_re}\s*|{block_end_re}))"
+        )
+        root_parts_re = "|".join(
+            [root_raw_re] + [rf"(?P<{n}>{r}(\-|\+|))" for n, r in root_tag_rules]
+        )
+
+        # global lexing rules
+        self.rules: t.Dict[str, t.List[_Rule]] = {
+            "root": [
+                # directives
+                _Rule(
+                    c(rf"(.*?)(?:{root_parts_re})"),
+                    OptionalLStrip(TOKEN_DATA, "#bygroup"),  # type: ignore
+                    "#bygroup",
+                ),
+                # data
+                _Rule(c(".+"), TOKEN_DATA, None),
+            ],
+            # comments
+            TOKEN_COMMENT_BEGIN: [
+                _Rule(
+                    c(
+                        rf"(.*?)((?:\+{comment_end_re}|\-{comment_end_re}\s*"
+                        rf"|{comment_end_re}{block_suffix_re}))"
+                    ),
+                    (TOKEN_COMMENT, TOKEN_COMMENT_END),
+                    "#pop",
+                ),
+                _Rule(c(r"(.)"), (Failure("Missing end of comment tag"),), None),
+            ],
+            # blocks
+            TOKEN_BLOCK_BEGIN: [
+                _Rule(
+                    c(
+                        rf"(?:\+{block_end_re}|\-{block_end_re}\s*"
+                        rf"|{block_end_re}{block_suffix_re})"
+                    ),
+                    TOKEN_BLOCK_END,
+                    "#pop",
+                ),
+            ]
+            + tag_rules,
+            # variables
+            TOKEN_VARIABLE_BEGIN: [
+                _Rule(
+                    c(rf"\-{variable_end_re}\s*|{variable_end_re}"),
+                    TOKEN_VARIABLE_END,
+                    "#pop",
+                )
+            ]
+            + tag_rules,
+            # raw block
+            TOKEN_RAW_BEGIN: [
+                _Rule(
+                    c(
+                        rf"(.*?)((?:{block_start_re}(\-|\+|))\s*endraw\s*"
+                        rf"(?:\+{block_end_re}|\-{block_end_re}\s*"
+                        rf"|{block_end_re}{block_suffix_re}))"
+                    ),
+                    OptionalLStrip(TOKEN_DATA, TOKEN_RAW_END),  # type: ignore
+                    "#pop",
+                ),
+                _Rule(c(r"(.)"), (Failure("Missing end of raw directive"),), None),
+            ],
+            # line statements
+            TOKEN_LINESTATEMENT_BEGIN: [
+                _Rule(c(r"\s*(\n|$)"), TOKEN_LINESTATEMENT_END, "#pop")
+            ]
+            + tag_rules,
+            # line comments
+            TOKEN_LINECOMMENT_BEGIN: [
+                _Rule(
+                    c(r"(.*?)()(?=\n|$)"),
+                    (TOKEN_LINECOMMENT, TOKEN_LINECOMMENT_END),
+                    "#pop",
+                )
+            ],
+        }
+
+    def _normalize_newlines(self, value: str) -> str:
+        """Replace all newlines with the configured sequence in strings
+        and template data.
+        """
+        return newline_re.sub(self.newline_sequence, value)
+
+    def tokenize(
+        self,
+        source: str,
+        name: t.Optional[str] = None,
+        filename: t.Optional[str] = None,
+        state: t.Optional[str] = None,
+    ) -> TokenStream:
+        """Calls tokeniter + tokenize and wraps it in a token stream."""
+        stream = self.tokeniter(source, name, filename, state)
+        return TokenStream(self.wrap(stream, name, filename), name, filename)
+
+    def wrap(
+        self,
+        stream: t.Iterable[t.Tuple[int, str, str]],
+        name: t.Optional[str] = None,
+        filename: t.Optional[str] = None,
+    ) -> t.Iterator[Token]:
+        """This is called with the stream as returned by `tokenize` and wraps
+        every token in a :class:`Token` and converts the value.
+        """
+        for lineno, token, value_str in stream:
+            if token in ignored_tokens:
+                continue
+
+            value: t.Any = value_str
+
+            if token == TOKEN_LINESTATEMENT_BEGIN:
+                token = TOKEN_BLOCK_BEGIN
+            elif token == TOKEN_LINESTATEMENT_END:
+                token = TOKEN_BLOCK_END
+            # we are not interested in those tokens in the parser
+            elif token in (TOKEN_RAW_BEGIN, TOKEN_RAW_END):
+                continue
+            elif token == TOKEN_DATA:
+                value = self._normalize_newlines(value_str)
+            elif token == "keyword":
+                token = value_str
+            elif token == TOKEN_NAME:
+                value = value_str
+
+                if not value.isidentifier():
+                    raise TemplateSyntaxError(
+                        "Invalid character in identifier", lineno, name, filename
+                    )
+            elif token == TOKEN_STRING:
+                # try to unescape string
+                try:
+                    value = (
+                        self._normalize_newlines(value_str[1:-1])
+                        .encode("ascii", "backslashreplace")
+                        .decode("unicode-escape")
+                    )
+                except Exception as e:
+                    msg = str(e).split(":")[-1].strip()
+                    raise TemplateSyntaxError(msg, lineno, name, filename) from e
+            elif token == TOKEN_INTEGER:
+                value = int(value_str.replace("_", ""), 0)
+            elif token == TOKEN_FLOAT:
+                # remove all "_" first to support more Python versions
+                value = literal_eval(value_str.replace("_", ""))
+            elif token == TOKEN_OPERATOR:
+                token = operators[value_str]
+
+            yield Token(lineno, token, value)
+
+    def tokeniter(
+        self,
+        source: str,
+        name: t.Optional[str],
+        filename: t.Optional[str] = None,
+        state: t.Optional[str] = None,
+    ) -> t.Iterator[t.Tuple[int, str, str]]:
+        """This method tokenizes the text and returns the tokens in a
+        generator. Use this method if you just want to tokenize a template.
+
+        .. versionchanged:: 3.0
+            Only ``\\n``, ``\\r\\n`` and ``\\r`` are treated as line
+            breaks.
+        """
+        lines = newline_re.split(source)[::2]
+
+        if not self.keep_trailing_newline and lines[-1] == "":
+            del lines[-1]
+
+        source = "\n".join(lines)
+        pos = 0
+        lineno = 1
+        stack = ["root"]
+
+        if state is not None and state != "root":
+            assert state in ("variable", "block"), "invalid state"
+            stack.append(state + "_begin")
+
+        statetokens = self.rules[stack[-1]]
+        source_length = len(source)
+        balancing_stack: t.List[str] = []
+        newlines_stripped = 0
+        line_starting = True
+
+        while True:
+            # tokenizer loop
+            for regex, tokens, new_state in statetokens:
+                m = regex.match(source, pos)
+
+                # if no match we try again with the next rule
+                if m is None:
+                    continue
+
+                # we only match blocks and variables if braces / parentheses
+                # are balanced. continue parsing with the lower rule which
+                # is the operator rule. do this only if the end tags look
+                # like operators
+                if balancing_stack and tokens in (
+                    TOKEN_VARIABLE_END,
+                    TOKEN_BLOCK_END,
+                    TOKEN_LINESTATEMENT_END,
+                ):
+                    continue
+
+                # tuples support more options
+                if isinstance(tokens, tuple):
+                    groups: t.Sequence[str] = m.groups()
+
+                    if isinstance(tokens, OptionalLStrip):
+                        # Rule supports lstrip. Match will look like
+                        # text, block type, whitespace control, type, control, ...
+                        text = groups[0]
+                        # Skipping the text and first type, every other group is the
+                        # whitespace control for each type. One of the groups will be
+                        # -, +, or empty string instead of None.
+                        strip_sign = next(g for g in groups[2::2] if g is not None)
+
+                        if strip_sign == "-":
+                            # Strip all whitespace between the text and the tag.
+                            stripped = text.rstrip()
+                            newlines_stripped = text[len(stripped) :].count("\n")
+                            groups = [stripped, *groups[1:]]
+                        elif (
+                            # Not marked for preserving whitespace.
+                            strip_sign != "+"
+                            # lstrip is enabled.
+                            and self.lstrip_blocks
+                            # Not a variable expression.
+                            and not m.groupdict().get(TOKEN_VARIABLE_BEGIN)
+                        ):
+                            # The start of text between the last newline and the tag.
+                            l_pos = text.rfind("\n") + 1
+
+                            if l_pos > 0 or line_starting:
+                                # If there's only whitespace between the newline and the
+                                # tag, strip it.
+                                if whitespace_re.fullmatch(text, l_pos):
+                                    groups = [text[:l_pos], *groups[1:]]
+
+                    for idx, token in enumerate(tokens):
+                        # failure group
+                        if isinstance(token, Failure):
+                            raise token(lineno, filename)
+                        # bygroup is a bit more complex, in that case we
+                        # yield for the current token the first named
+                        # group that matched
+                        elif token == "#bygroup":
+                            for key, value in m.groupdict().items():
+                                if value is not None:
+                                    yield lineno, key, value
+                                    lineno += value.count("\n")
+                                    break
+                            else:
+                                raise RuntimeError(
+                                    f"{regex!r} wanted to resolve the token dynamically"
+                                    " but no group matched"
+                                )
+                        # normal group
+                        else:
+                            data = groups[idx]
+
+                            if data or token not in ignore_if_empty:
+                                yield lineno, token, data  # type: ignore[misc]
+
+                            lineno += data.count("\n") + newlines_stripped
+                            newlines_stripped = 0
+
+                # strings as token just are yielded as it.
+                else:
+                    data = m.group()
+
+                    # update brace/parentheses balance
+                    if tokens == TOKEN_OPERATOR:
+                        if data == "{":
+                            balancing_stack.append("}")
+                        elif data == "(":
+                            balancing_stack.append(")")
+                        elif data == "[":
+                            balancing_stack.append("]")
+                        elif data in ("}", ")", "]"):
+                            if not balancing_stack:
+                                raise TemplateSyntaxError(
+                                    f"unexpected '{data}'", lineno, name, filename
+                                )
+
+                            expected_op = balancing_stack.pop()
+
+                            if expected_op != data:
+                                raise TemplateSyntaxError(
+                                    f"unexpected '{data}', expected '{expected_op}'",
+                                    lineno,
+                                    name,
+                                    filename,
+                                )
+
+                    # yield items
+                    if data or tokens not in ignore_if_empty:
+                        yield lineno, tokens, data
+
+                    lineno += data.count("\n")
+
+                line_starting = m.group()[-1:] == "\n"
+                # fetch new position into new variable so that we can check
+                # if there is a internal parsing error which would result
+                # in an infinite loop
+                pos2 = m.end()
+
+                # handle state changes
+                if new_state is not None:
+                    # remove the uppermost state
+                    if new_state == "#pop":
+                        stack.pop()
+                    # resolve the new state by group checking
+                    elif new_state == "#bygroup":
+                        for key, value in m.groupdict().items():
+                            if value is not None:
+                                stack.append(key)
+                                break
+                        else:
+                            raise RuntimeError(
+                                f"{regex!r} wanted to resolve the new state dynamically"
+                                f" but no group matched"
+                            )
+                    # direct state name given
+                    else:
+                        stack.append(new_state)
+
+                    statetokens = self.rules[stack[-1]]
+                # we are still at the same position and no stack change.
+                # this means a loop without break condition, avoid that and
+                # raise error
+                elif pos2 == pos:
+                    raise RuntimeError(
+                        f"{regex!r} yielded empty string without stack change"
+                    )
+
+                # publish new function and start again
+                pos = pos2
+                break
+            # if loop terminated without break we haven't found a single match
+            # either we are at the end of the file or we have a problem
+            else:
+                # end of text
+                if pos >= source_length:
+                    return
+
+                # something went wrong
+                raise TemplateSyntaxError(
+                    f"unexpected char {source[pos]!r} at {pos}", lineno, name, filename
+                )