markdown_it.ruler 源代码

"""
class Ruler

Helper class, used by [[MarkdownIt#core]], [[MarkdownIt#block]] and
[[MarkdownIt#inline]] to manage sequences of functions (rules):

- keep rules in defined order
- assign the name to each rule
- enable/disable rules
- add/replace rules
- allow assign rules to additional named chains (in the same)
- cacheing lists of active rules

You will not need use this class directly until write plugins. For simple
rules control use [[MarkdownIt.disable]], [[MarkdownIt.enable]] and
[[MarkdownIt.use]].
"""
from typing import (
    Callable,
    Dict,
    Iterable,
    List,
    MutableMapping,
    Optional,
    Tuple,
    TYPE_CHECKING,
    Union,
)
import attr

if TYPE_CHECKING:
    from markdown_it import MarkdownIt


[文档]class StateBase: srcCharCode: Tuple[int, ...] def __init__(self, src: str, md: "MarkdownIt", env: MutableMapping): self.src = src self.env = env self.md = md @property def src(self) -> str: return self._src @src.setter def src(self, value: str) -> None: self._src = value self.srcCharCode = tuple(ord(c) for c in self.src)
# The first positional arg is always a subtype of `StateBase`. Other # arguments may or may not exist, based on the rule's type (block, # core, inline). Return type is either `None` or `bool` based on the # rule's type. RuleFunc = Callable
[文档]@attr.s(slots=True) class Rule: name: str = attr.ib() enabled: bool = attr.ib() fn: RuleFunc = attr.ib(repr=False) alt: List[str] = attr.ib()
[文档]class Ruler: def __init__(self): # List of added rules. self.__rules__: List[Rule] = [] # Cached rule chains. # First level - chain name, '' for default. # Second level - diginal anchor for fast filtering by charcodes. self.__cache__: Optional[Dict[str, List[RuleFunc]]] = None def __find__(self, name: str) -> int: """Find rule index by name""" for i, rule in enumerate(self.__rules__): if rule.name == name: return i return -1 def __compile__(self) -> None: """Build rules lookup cache""" chains = {""} # collect unique names for rule in self.__rules__: if not rule.enabled: continue for name in rule.alt: chains.add(name) self.__cache__ = {} for chain in chains: self.__cache__[chain] = [] for rule in self.__rules__: if not rule.enabled: continue if chain and (chain not in rule.alt): continue self.__cache__[chain].append(rule.fn)
[文档] def at(self, ruleName: str, fn: RuleFunc, options=None): """Replace rule by name with new function & options. :param ruleName: rule name to replace. :param fn: new rule function. :param options: new rule options (not mandatory). :raises: KeyError if name not found """ index = self.__find__(ruleName) options = options or {} if index == -1: raise KeyError(f"Parser rule not found: {ruleName}") self.__rules__[index].fn = fn self.__rules__[index].alt = options.get("alt", []) self.__cache__ = None
[文档] def before(self, beforeName: str, ruleName: str, fn: RuleFunc, options=None): """Add new rule to chain before one with given name. :param beforeName: new rule will be added before this one. :param ruleName: new rule will be added before this one. :param fn: new rule function. :param options: new rule options (not mandatory). :raises: KeyError if name not found """ index = self.__find__(beforeName) options = options or {} if index == -1: raise KeyError(f"Parser rule not found: {beforeName}") self.__rules__.insert(index, Rule(ruleName, True, fn, options.get("alt", []))) self.__cache__ = None
[文档] def after(self, afterName: str, ruleName: str, fn: RuleFunc, options=None): """Add new rule to chain after one with given name. :param afterName: new rule will be added after this one. :param ruleName: new rule will be added after this one. :param fn: new rule function. :param options: new rule options (not mandatory). :raises: KeyError if name not found """ index = self.__find__(afterName) options = options or {} if index == -1: raise KeyError(f"Parser rule not found: {afterName}") self.__rules__.insert( index + 1, Rule(ruleName, True, fn, options.get("alt", [])) ) self.__cache__ = None
[文档] def push(self, ruleName: str, fn: RuleFunc, options=None): """Push new rule to the end of chain. :param ruleName: new rule will be added to the end of chain. :param fn: new rule function. :param options: new rule options (not mandatory). """ self.__rules__.append(Rule(ruleName, True, fn, (options or {}).get("alt", []))) self.__cache__ = None
[文档] def enable(self, names: Union[str, Iterable[str]], ignoreInvalid: bool = False): """Enable rules with given names. :param names: name or list of rule names to enable. :param ignoreInvalid: ignore errors when rule not found :raises: KeyError if name not found and not ignoreInvalid :return: list of found rule names """ if isinstance(names, str): names = [names] result = [] for name in names: idx = self.__find__(name) if (idx < 0) and ignoreInvalid: continue if (idx < 0) and not ignoreInvalid: raise KeyError(f"Rules manager: invalid rule name {name}") self.__rules__[idx].enabled = True result.append(name) self.__cache__ = None return result
[文档] def enableOnly(self, names: Union[str, Iterable[str]], ignoreInvalid: bool = False): """Enable rules with given names, and disable everything else. :param names: name or list of rule names to enable. :param ignoreInvalid: ignore errors when rule not found :raises: KeyError if name not found and not ignoreInvalid :return: list of found rule names """ if isinstance(names, str): names = [names] for rule in self.__rules__: rule.enabled = False self.enable(names, ignoreInvalid)
[文档] def disable(self, names: Union[str, Iterable[str]], ignoreInvalid: bool = False): """Disable rules with given names. :param names: name or list of rule names to enable. :param ignoreInvalid: ignore errors when rule not found :raises: KeyError if name not found and not ignoreInvalid :return: list of found rule names """ if isinstance(names, str): names = [names] result = [] for name in names: idx = self.__find__(name) if (idx < 0) and ignoreInvalid: continue if (idx < 0) and not ignoreInvalid: raise KeyError(f"Rules manager: invalid rule name {name}") self.__rules__[idx].enabled = False result.append(name) self.__cache__ = None return result
[文档] def getRules(self, chainName: str) -> List[RuleFunc]: """Return array of active functions (rules) for given chain name. It analyzes rules configuration, compiles caches if not exists and returns result. Default chain name is `''` (empty string). It can't be skipped. That's done intentionally, to keep signature monomorphic for high speed. """ if self.__cache__ is None: self.__compile__() assert self.__cache__ is not None # Chain can be empty, if rules disabled. But we still have to return Array. return self.__cache__.get(chainName, []) or []
[文档] def get_all_rules(self) -> List[str]: """Return all available rule names.""" return [r.name for r in self.__rules__]
[文档] def get_active_rules(self) -> List[str]: """Return the active rule names.""" return [r.name for r in self.__rules__ if r.enabled]