site/node_modules/micromark-core-commonmark/lib/attention.js
2024-10-14 08:09:33 +02:00

264 lines
7.7 KiB
JavaScript
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/**
* @typedef {import('micromark-util-types').Code} Code
* @typedef {import('micromark-util-types').Construct} Construct
* @typedef {import('micromark-util-types').Event} Event
* @typedef {import('micromark-util-types').Point} Point
* @typedef {import('micromark-util-types').Resolver} Resolver
* @typedef {import('micromark-util-types').State} State
* @typedef {import('micromark-util-types').Token} Token
* @typedef {import('micromark-util-types').TokenizeContext} TokenizeContext
* @typedef {import('micromark-util-types').Tokenizer} Tokenizer
*/
import {push, splice} from 'micromark-util-chunked'
import {classifyCharacter} from 'micromark-util-classify-character'
import {resolveAll} from 'micromark-util-resolve-all'
/** @type {Construct} */
export const attention = {
name: 'attention',
tokenize: tokenizeAttention,
resolveAll: resolveAllAttention
}
/**
* Take all events and resolve attention to emphasis or strong.
*
* @type {Resolver}
*/
// eslint-disable-next-line complexity
function resolveAllAttention(events, context) {
let index = -1
/** @type {number} */
let open
/** @type {Token} */
let group
/** @type {Token} */
let text
/** @type {Token} */
let openingSequence
/** @type {Token} */
let closingSequence
/** @type {number} */
let use
/** @type {Array<Event>} */
let nextEvents
/** @type {number} */
let offset
// Walk through all events.
//
// Note: performance of this is fine on an mb of normal markdown, but its
// a bottleneck for malicious stuff.
while (++index < events.length) {
// Find a token that can close.
if (
events[index][0] === 'enter' &&
events[index][1].type === 'attentionSequence' &&
events[index][1]._close
) {
open = index
// Now walk back to find an opener.
while (open--) {
// Find a token that can open the closer.
if (
events[open][0] === 'exit' &&
events[open][1].type === 'attentionSequence' &&
events[open][1]._open &&
// If the markers are the same:
context.sliceSerialize(events[open][1]).charCodeAt(0) ===
context.sliceSerialize(events[index][1]).charCodeAt(0)
) {
// If the opening can close or the closing can open,
// and the close size *is not* a multiple of three,
// but the sum of the opening and closing size *is* multiple of three,
// then dont match.
if (
(events[open][1]._close || events[index][1]._open) &&
(events[index][1].end.offset - events[index][1].start.offset) % 3 &&
!(
(events[open][1].end.offset -
events[open][1].start.offset +
events[index][1].end.offset -
events[index][1].start.offset) %
3
)
) {
continue
}
// Number of markers to use from the sequence.
use =
events[open][1].end.offset - events[open][1].start.offset > 1 &&
events[index][1].end.offset - events[index][1].start.offset > 1
? 2
: 1
const start = Object.assign({}, events[open][1].end)
const end = Object.assign({}, events[index][1].start)
movePoint(start, -use)
movePoint(end, use)
openingSequence = {
type: use > 1 ? 'strongSequence' : 'emphasisSequence',
start,
end: Object.assign({}, events[open][1].end)
}
closingSequence = {
type: use > 1 ? 'strongSequence' : 'emphasisSequence',
start: Object.assign({}, events[index][1].start),
end
}
text = {
type: use > 1 ? 'strongText' : 'emphasisText',
start: Object.assign({}, events[open][1].end),
end: Object.assign({}, events[index][1].start)
}
group = {
type: use > 1 ? 'strong' : 'emphasis',
start: Object.assign({}, openingSequence.start),
end: Object.assign({}, closingSequence.end)
}
events[open][1].end = Object.assign({}, openingSequence.start)
events[index][1].start = Object.assign({}, closingSequence.end)
nextEvents = []
// If there are more markers in the opening, add them before.
if (events[open][1].end.offset - events[open][1].start.offset) {
nextEvents = push(nextEvents, [
['enter', events[open][1], context],
['exit', events[open][1], context]
])
}
// Opening.
nextEvents = push(nextEvents, [
['enter', group, context],
['enter', openingSequence, context],
['exit', openingSequence, context],
['enter', text, context]
])
// Always populated by defaults.
// Between.
nextEvents = push(
nextEvents,
resolveAll(
context.parser.constructs.insideSpan.null,
events.slice(open + 1, index),
context
)
)
// Closing.
nextEvents = push(nextEvents, [
['exit', text, context],
['enter', closingSequence, context],
['exit', closingSequence, context],
['exit', group, context]
])
// If there are more markers in the closing, add them after.
if (events[index][1].end.offset - events[index][1].start.offset) {
offset = 2
nextEvents = push(nextEvents, [
['enter', events[index][1], context],
['exit', events[index][1], context]
])
} else {
offset = 0
}
splice(events, open - 1, index - open + 3, nextEvents)
index = open + nextEvents.length - offset - 2
break
}
}
}
}
// Remove remaining sequences.
index = -1
while (++index < events.length) {
if (events[index][1].type === 'attentionSequence') {
events[index][1].type = 'data'
}
}
return events
}
/**
* @this {TokenizeContext}
* @type {Tokenizer}
*/
function tokenizeAttention(effects, ok) {
const attentionMarkers = this.parser.constructs.attentionMarkers.null
const previous = this.previous
const before = classifyCharacter(previous)
/** @type {NonNullable<Code>} */
let marker
return start
/**
* Before a sequence.
*
* ```markdown
* > | **
* ^
* ```
*
* @type {State}
*/
function start(code) {
marker = code
effects.enter('attentionSequence')
return inside(code)
}
/**
* In a sequence.
*
* ```markdown
* > | **
* ^^
* ```
*
* @type {State}
*/
function inside(code) {
if (code === marker) {
effects.consume(code)
return inside
}
const token = effects.exit('attentionSequence')
// To do: next major: move this to resolver, just like `markdown-rs`.
const after = classifyCharacter(code)
// Always populated by defaults.
const open =
!after || (after === 2 && before) || attentionMarkers.includes(code)
const close =
!before || (before === 2 && after) || attentionMarkers.includes(previous)
token._open = Boolean(marker === 42 ? open : open && (before || !close))
token._close = Boolean(marker === 42 ? close : close && (after || !open))
return ok(code)
}
}
/**
* Move a point a bit.
*
* Note: `move` only works inside lines! Its not possible to move past other
* chunks (replacement characters, tabs, or line endings).
*
* @param {Point} point
* @param {number} offset
* @returns {undefined}
*/
function movePoint(point, offset) {
point.column += offset
point.offset += offset
point._bufferIndex += offset
}