100 lines
3.8 KiB
JavaScript
100 lines
3.8 KiB
JavaScript
// Copyright BigchainDB GmbH and BigchainDB contributors
|
|
// SPDX-License-Identifier: (Apache-2.0 AND CC-BY-4.0)
|
|
// Code is Apache-2.0 and docs are CC-BY-4.0
|
|
|
|
import { sprintf } from 'sprintf-js'
|
|
|
|
// Regexes taken from or inspired by sprintf-js
|
|
const Regex = {
|
|
TEMPLATE_LITERAL: /\${([^)]+?)}/g,
|
|
KEY: /^([a-z_][a-z_\d]*)/i,
|
|
KEY_ACCESS: /^\.([a-z_][a-z_\d]*)/i,
|
|
INDEX_ACCESS: /^\[(\d+)\]/
|
|
}
|
|
|
|
/**
|
|
* imported from https://github.com/bigchaindb/js-utility-belt/
|
|
* @private
|
|
* Formats strings similarly to C's sprintf, with the addition of '${...}' formats.
|
|
*
|
|
* Makes a first pass replacing '${...}' formats before passing the expanded string and other
|
|
* arguments to sprintf-js. For more information on what sprintf can do, see
|
|
* https://github.com/alexei/sprintf.js.
|
|
*
|
|
* Examples:
|
|
* formatText('Hi there ${dimi}!', { dimi: 'Dimi' })
|
|
* => 'Hi there Dimi!'
|
|
*
|
|
* formatText('${database} is %(status)s', { database: 'BigchainDB', status: 'big' })
|
|
* => 'BigchainDB is big'
|
|
*
|
|
* Like sprintf-js, string interpolation for keywords and indexes is supported too:
|
|
* formatText('Berlin is best known for its ${berlin.topKnownFor[0].name}', {
|
|
* berlin: {
|
|
* topKnownFor: [{
|
|
* name: 'Currywurst'
|
|
* }, ...
|
|
* ]
|
|
* }
|
|
* })
|
|
* => 'Berlin is best known for its Currywurst'
|
|
*/
|
|
export default function formatText(s, ...argv) {
|
|
let expandedFormatStr = s
|
|
|
|
// Try to replace formats of the form '${...}' if named replacement fields are used
|
|
if (s && argv.length === 1 && typeof argv[0] === 'object') {
|
|
const templateSpecObj = argv[0]
|
|
|
|
expandedFormatStr = s.replace(Regex.TEMPLATE_LITERAL, (match, replacement) => {
|
|
let interpolationLeft = replacement
|
|
|
|
/**
|
|
* @private
|
|
* Interpolation algorithm inspired by sprintf-js.
|
|
*
|
|
* Goes through the replacement string getting the left-most key or index to interpolate
|
|
* on each pass. `value` at each step holds the last interpolation result, `curMatch` is
|
|
* the current property match, and `interpolationLeft` is the portion of the replacement
|
|
* string still to be interpolated.
|
|
*
|
|
* It's useful to note that RegExp.exec() returns with an array holding:
|
|
* [0]: Full string matched
|
|
* [1+]: Matching groups
|
|
*
|
|
* And that in the regexes defined, the first matching group always corresponds to the
|
|
* property matched.
|
|
*/
|
|
let value
|
|
let curMatch = Regex.KEY.exec(interpolationLeft)
|
|
if (curMatch !== null) {
|
|
value = templateSpecObj[curMatch[1]]
|
|
|
|
// Assigning in the conditionals here makes the code less bloated
|
|
/* eslint-disable no-cond-assign */
|
|
while ((interpolationLeft = interpolationLeft.substring(curMatch[0].length)) &&
|
|
value != null) {
|
|
if ((curMatch = Regex.KEY_ACCESS.exec(interpolationLeft))) {
|
|
value = value[curMatch[1]]
|
|
} else if ((curMatch = Regex.INDEX_ACCESS.exec(interpolationLeft))) {
|
|
value = value[curMatch[1]]
|
|
} else {
|
|
break
|
|
}
|
|
}
|
|
/* eslint-enable no-cond-assign */
|
|
}
|
|
|
|
// If there's anything left to interpolate by the end then we've failed to interpolate
|
|
// the entire replacement string.
|
|
if (interpolationLeft.length) {
|
|
throw new SyntaxError(`[formatText] failed to parse named argument key: ${replacement}`)
|
|
}
|
|
|
|
return value
|
|
})
|
|
}
|
|
|
|
return sprintf(expandedFormatStr, ...argv)
|
|
}
|