70 lines
1.6 KiB
JavaScript
70 lines
1.6 KiB
JavaScript
|
/**
|
||
|
|
* @typedef {import('micromark-util-types').Effects} Effects
|
||
|
|
* @typedef {import('micromark-util-types').State} State
|
||
|
|
* @typedef {import('micromark-util-types').TokenType} TokenType
|
||
|
|
*/
|
||
|
|
|
||
|
|
import {markdownSpace} from 'micromark-util-character'
|
||
|
|
|
||
|
|
// To do: implement `spaceOrTab`, `spaceOrTabMinMax`, `spaceOrTabWithOptions`.
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Parse spaces and tabs.
|
||
|
|
*
|
||
|
|
* There is no `nok` parameter:
|
||
|
|
*
|
||
|
|
* * spaces in markdown are often optional, in which case this factory can be
|
||
|
|
* used and `ok` will be switched to whether spaces were found or not
|
||
|
|
* * one line ending or space can be detected with `markdownSpace(code)` right
|
||
|
|
* before using `factorySpace`
|
||
|
|
*
|
||
|
|
* ###### Examples
|
||
|
|
*
|
||
|
|
* Where `␉` represents a tab (plus how much it expands) and `␠` represents a
|
||
|
|
* single space.
|
||
|
|
*
|
||
|
|
* ```markdown
|
||
|
|
* ␉
|
||
|
|
* ␠␠␠␠
|
||
|
|
* ␉␠
|
||
|
|
* ```
|
||
|
|
*
|
||
|
|
* @param {Effects} effects
|
||
|
|
* Context.
|
||
|
|
* @param {State} ok
|
||
|
|
* State switched to when successful.
|
||
|
|
* @param {TokenType} type
|
||
|
|
* Type (`' \t'`).
|
||
|
|
* @param {number | undefined} [max=Infinity]
|
||
|
|
* Max (exclusive).
|
||
|
|
* @returns {State}
|
||
|
|
* Start state.
|
||
|
|
*/
|
||
|
|
export function factorySpace(effects, ok, type, max) {
|
||
|
|
const limit = max ? max - 1 : Number.POSITIVE_INFINITY
|
||
|
|
let size = 0
|
||
|
|
|
||
|
|
return start
|
||
|
|
|
||
|
|
/** @type {State} */
|
||
|
|
function start(code) {
|
||
|
|
if (markdownSpace(code)) {
|
||
|
|
effects.enter(type)
|
||
|
|
return prefix(code)
|
||
|
|
}
|
||
|
|
|
||
|
|
return ok(code)
|
||
|
|
}
|
||
|
|
|
||
|
|
/** @type {State} */
|
||
|
|
function prefix(code) {
|
||
|
|
if (markdownSpace(code) && size++ < limit) {
|
||
|
|
effects.consume(code)
|
||
|
|
return prefix
|
||
|
|
}
|
||
|
|
|
||
|
|
effects.exit(type)
|
||
|
|
return ok(code)
|
||
|
|
}
|
||
|
|
}
|