35 lines
885 B
JavaScript
35 lines
885 B
JavaScript
/**
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* @typedef {import('hast').Nodes} Nodes
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*/
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// HTML whitespace expression.
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// See <https://infra.spec.whatwg.org/#ascii-whitespace>.
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const re = /[ \t\n\f\r]/g
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/**
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* Check if the given value is *inter-element whitespace*.
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*
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* @param {Nodes | string} thing
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* Thing to check (`Node` or `string`).
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* @returns {boolean}
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* Whether the `value` is inter-element whitespace (`boolean`): consisting of
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* zero or more of space, tab (`\t`), line feed (`\n`), carriage return
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* (`\r`), or form feed (`\f`); if a node is passed it must be a `Text` node,
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* whose `value` field is checked.
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*/
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export function whitespace(thing) {
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return typeof thing === 'object'
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? thing.type === 'text'
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? empty(thing.value)
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: false
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: empty(thing)
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}
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/**
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* @param {string} value
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* @returns {boolean}
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*/
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function empty(value) {
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return value.replace(re, '') === ''
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}
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