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import createTester from './internal/createTester';
import eachOf from './eachOf'
import awaitify from './internal/awaitify'
/**
* Returns `true` if every element in `coll` satisfies an async test. If any
* iteratee call returns `false`, the main `callback` is immediately called.
*
* @name every
* @static
* @memberOf module:Collections
* @method
* @alias all
* @category Collection
* @param {Array|Iterable|AsyncIterable|Object} coll - A collection to iterate over.
* @param {AsyncFunction} iteratee - An async truth test to apply to each item
* in the collection in parallel.
* The iteratee must complete with a boolean result value.
* Invoked with (item, callback).
* @param {Function} [callback] - A callback which is called after all the
* `iteratee` functions have finished. Result will be either `true` or `false`
* depending on the values of the async tests. Invoked with (err, result).
* @returns {Promise} a promise, if no callback provided
* @example
*
* // dir1 is a directory that contains file1.txt, file2.txt
* // dir2 is a directory that contains file3.txt, file4.txt
* // dir3 is a directory that contains file5.txt
* // dir4 does not exist
*
* const fileList = ['dir1/file1.txt','dir2/file3.txt','dir3/file5.txt'];
* const withMissingFileList = ['file1.txt','file2.txt','file4.txt'];
*
* // asynchronous function that checks if a file exists
* function fileExists(file, callback) {
* fs.access(file, fs.constants.F_OK, (err) => {
* callback(null, !err);
* });
* }
*
* // Using callbacks
* async.every(fileList, fileExists, function(err, result) {
* console.log(result);
* // true
* // result is true since every file exists
* });
*
* async.every(withMissingFileList, fileExists, function(err, result) {
* console.log(result);
* // false
* // result is false since NOT every file exists
* });
*
* // Using Promises
* async.every(fileList, fileExists)
* .then( result => {
* console.log(result);
* // true
* // result is true since every file exists
* }).catch( err => {
* console.log(err);
* });
*
* async.every(withMissingFileList, fileExists)
* .then( result => {
* console.log(result);
* // false
* // result is false since NOT every file exists
* }).catch( err => {
* console.log(err);
* });
*
* // Using async/await
* async () => {
* try {
* let result = await async.every(fileList, fileExists);
* console.log(result);
* // true
* // result is true since every file exists
* }
* catch (err) {
* console.log(err);
* }
* }
*
* async () => {
* try {
* let result = await async.every(withMissingFileList, fileExists);
* console.log(result);
* // false
* // result is false since NOT every file exists
* }
* catch (err) {
* console.log(err);
* }
* }
*
*/
function every(coll, iteratee, callback) {
return createTester(bool => !bool, res => !res)(eachOf, coll, iteratee, callback)
}
export default awaitify(every, 3);
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