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

118 lines
2.3 KiB
JavaScript

/**
* @typedef {import('micromark-util-types').Code} Code
* @typedef {import('micromark-util-types').Construct} Construct
* @typedef {import('micromark-util-types').State} State
* @typedef {import('micromark-util-types').TokenizeContext} TokenizeContext
* @typedef {import('micromark-util-types').Tokenizer} Tokenizer
*/
import {factorySpace} from 'micromark-factory-space'
import {markdownLineEnding, markdownSpace} from 'micromark-util-character'
import {codes, constants, types} from 'micromark-util-symbol'
import {ok as assert} from 'devlop'
/** @type {Construct} */
export const thematicBreak = {
name: 'thematicBreak',
tokenize: tokenizeThematicBreak
}
/**
* @this {TokenizeContext}
* @type {Tokenizer}
*/
function tokenizeThematicBreak(effects, ok, nok) {
let size = 0
/** @type {NonNullable<Code>} */
let marker
return start
/**
* Start of thematic break.
*
* ```markdown
* > | ***
* ^
* ```
*
* @type {State}
*/
function start(code) {
effects.enter(types.thematicBreak)
// To do: parse indent like `markdown-rs`.
return before(code)
}
/**
* After optional whitespace, at marker.
*
* ```markdown
* > | ***
* ^
* ```
*
* @type {State}
*/
function before(code) {
assert(
code === codes.asterisk ||
code === codes.dash ||
code === codes.underscore,
'expected `*`, `-`, or `_`'
)
marker = code
return atBreak(code)
}
/**
* After something, before something else.
*
* ```markdown
* > | ***
* ^
* ```
*
* @type {State}
*/
function atBreak(code) {
if (code === marker) {
effects.enter(types.thematicBreakSequence)
return sequence(code)
}
if (
size >= constants.thematicBreakMarkerCountMin &&
(code === codes.eof || markdownLineEnding(code))
) {
effects.exit(types.thematicBreak)
return ok(code)
}
return nok(code)
}
/**
* In sequence.
*
* ```markdown
* > | ***
* ^
* ```
*
* @type {State}
*/
function sequence(code) {
if (code === marker) {
effects.consume(code)
size++
return sequence
}
effects.exit(types.thematicBreakSequence)
return markdownSpace(code)
? factorySpace(effects, atBreak, types.whitespace)(code)
: atBreak(code)
}
}