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Diffstat (limited to 'node_modules/p-locate/index.js')
-rw-r--r-- | node_modules/p-locate/index.js | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/node_modules/p-locate/index.js b/node_modules/p-locate/index.js new file mode 100644 index 0000000..e13ce15 --- /dev/null +++ b/node_modules/p-locate/index.js @@ -0,0 +1,52 @@ +'use strict'; +const pLimit = require('p-limit'); + +class EndError extends Error { + constructor(value) { + super(); + this.value = value; + } +} + +// The input can also be a promise, so we await it +const testElement = async (element, tester) => tester(await element); + +// The input can also be a promise, so we `Promise.all()` them both +const finder = async element => { + const values = await Promise.all(element); + if (values[1] === true) { + throw new EndError(values[0]); + } + + return false; +}; + +const pLocate = async (iterable, tester, options) => { + options = { + concurrency: Infinity, + preserveOrder: true, + ...options + }; + + const limit = pLimit(options.concurrency); + + // Start all the promises concurrently with optional limit + const items = [...iterable].map(element => [element, limit(testElement, element, tester)]); + + // Check the promises either serially or concurrently + const checkLimit = pLimit(options.preserveOrder ? 1 : Infinity); + + try { + await Promise.all(items.map(element => checkLimit(finder, element))); + } catch (error) { + if (error instanceof EndError) { + return error.value; + } + + throw error; + } +}; + +module.exports = pLocate; +// TODO: Remove this for the next major release +module.exports.default = pLocate; |