mdit-py-plugins/mdit_py_plugins/myst_blocks/index.py at 3f80e87c7d13a6015be3cab9030b8f4002a7af2d · executablebooks/mdit-py-plugins · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
import itertools

from markdown_it import MarkdownIt
from markdown_it.common.utils import escapeHtml, isSpace
from markdown_it.rules_block import StateBlock


def myst_block_plugin(md: MarkdownIt):
    """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):

    pos = state.bMarks[startLine] + state.tShift[startLine]
    maximum = state.eMarks[startLine]

    # if it's indented more than 3 spaces, it should be a code block
    if state.sCount[startLine] - state.blkIndent >= 4:
        return False

    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):

    pos = state.bMarks[startLine] + state.tShift[startLine]
    maximum = state.eMarks[startLine]

    # if it's indented more than 3 spaces, it should be a code block
    if state.sCount[startLine] - state.blkIndent >= 4:
        return False

    marker = state.srcCharCode[pos]
    pos += 1

    # Check block marker /* + */
    if marker != 0x2B:
        return False

    # markers can be mixed with spaces, but there should be at least 3 of them

    cnt = 1
    while pos < maximum:
        ch = state.srcCharCode[pos]
        if ch != marker and not isSpace(ch):
            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 = chr(marker) * cnt

    return True


def target(state: StateBlock, startLine: int, endLine: int, silent: bool):

    pos = state.bMarks[startLine] + state.tShift[startLine]
    maximum = state.eMarks[startLine]

    # if it's indented more than 3 spaces, it should be a code block
    if state.sCount[startLine] - state.blkIndent >= 4:
        return False

    text = state.src[pos:maximum].strip()
    if not text.startswith("("):
        return False
    if not text.endswith(")="):
        return False
    content = text[1:-2]
    if not content or "\\" in content:
        return False

    if silent:
        return True

    state.line = startLine + 1

    token = state.push("myst_target", "", 0)
    token.attrSet("class", "myst-target")
    token.content = content
    token.map = [startLine, state.line]

    return True


def render_myst_target(self, tokens, idx, options, env):
    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, tokens, idx, options, env):
    # Strip leading whitespace from all lines
    content = "\n".join(line.lstrip() for line in tokens[idx].content.split("\n"))
    return f"<!-- {escapeHtml(content)} -->"