from __future__ import annotations
import itertools
from typing import TYPE_CHECKING, Sequence
from markdown_it import MarkdownIt
from markdown_it.common.utils import escapeHtml
from markdown_it.rules_block import StateBlock
from mdit_py_plugins.utils import is_code_block
if TYPE_CHECKING:
from markdown_it.renderer import RendererProtocol
from markdown_it.token import Token
from markdown_it.utils import EnvType, OptionsDict
[docs]def myst_block_plugin(md: MarkdownIt) -> None:
"""Parse MyST targets (``(name)=``), blockquotes (``% comment``) and block breaks (``+++``)."""
md.block.ruler.before(
"blockquote",
"myst_line_comment",
line_comment,
{"alt": ["paragraph", "reference", "blockquote", "list", "footnote_def"]},
)
md.block.ruler.before(
"hr",
"myst_block_break",
block_break,
{"alt": ["paragraph", "reference", "blockquote", "list", "footnote_def"]},
)
md.block.ruler.before(
"hr",
"myst_target",
target,
{"alt": ["paragraph", "reference", "blockquote", "list", "footnote_def"]},
)
md.add_render_rule("myst_target", render_myst_target)
md.add_render_rule("myst_line_comment", render_myst_line_comment)
def line_comment(state: StateBlock, startLine: int, endLine: int, silent: bool) -> bool:
if is_code_block(state, startLine):
return False
pos = state.bMarks[startLine] + state.tShift[startLine]
maximum = state.eMarks[startLine]
if state.src[pos] != "%":
return False
if silent:
return True
token = state.push("myst_line_comment", "", 0)
token.attrSet("class", "myst-line-comment")
token.content = state.src[pos + 1 : maximum].rstrip()
token.markup = "%"
# search end of block while appending lines to `token.content`
for nextLine in itertools.count(startLine + 1):
if nextLine >= endLine:
break
pos = state.bMarks[nextLine] + state.tShift[nextLine]
maximum = state.eMarks[nextLine]
if state.src[pos] != "%":
break
token.content += "\n" + state.src[pos + 1 : maximum].rstrip()
state.line = nextLine
token.map = [startLine, nextLine]
return True
def block_break(state: StateBlock, startLine: int, endLine: int, silent: bool) -> bool:
if is_code_block(state, startLine):
return False
pos = state.bMarks[startLine] + state.tShift[startLine]
maximum = state.eMarks[startLine]
marker = state.src[pos]
pos += 1
# Check block marker
if marker != "+":
return False
# markers can be mixed with spaces, but there should be at least 3 of them
cnt = 1
while pos < maximum:
ch = state.src[pos]
if ch != marker and ch not in ("\t", " "):
break
if ch == marker:
cnt += 1
pos += 1
if cnt < 3:
return False
if silent:
return True
state.line = startLine + 1
token = state.push("myst_block_break", "hr", 0)
token.attrSet("class", "myst-block")
token.content = state.src[pos:maximum].strip()
token.map = [startLine, state.line]
token.markup = marker * cnt
return True
def target(state: StateBlock, startLine: int, endLine: int, silent: bool) -> bool:
if is_code_block(state, startLine):
return False
pos = state.bMarks[startLine] + state.tShift[startLine]
maximum = state.eMarks[startLine]
text = state.src[pos:maximum].strip()
if not text.startswith("("):
return False
if not text.endswith(")="):
return False
if not text[1:-2]:
return False
if silent:
return True
state.line = startLine + 1
token = state.push("myst_target", "", 0)
token.attrSet("class", "myst-target")
token.content = text[1:-2]
token.map = [startLine, state.line]
return True
def render_myst_target(
self: RendererProtocol,
tokens: Sequence[Token],
idx: int,
options: OptionsDict,
env: EnvType,
) -> str:
label = tokens[idx].content
class_name = "myst-target"
target = f'<a href="#{label}">({label})=</a>'
return f'<div class="{class_name}">{target}</div>'
def render_myst_line_comment(
self: RendererProtocol,
tokens: Sequence[Token],
idx: int,
options: OptionsDict,
env: EnvType,
) -> str:
# Strip leading whitespace from all lines
content = "\n".join(line.lstrip() for line in tokens[idx].content.split("\n"))
return f"<!-- {escapeHtml(content)} -->"