%PDF-
%PDF-
Mini Shell
Mini Shell
var hasStrictMode = require('has-strict-mode')();
var v = require('es-value-fixtures');
var forEach = require('for-each');
var inspect = require('object-inspect');
var maxSafeInteger = require('es-abstract/helpers/maxSafeInteger');
var global = require('globalthis')();
var trueThunk = function () { return true; };
var falseThunk = function () { return false; };
var canDistinguishSparseFromUndefined = 0 in [undefined]; // IE 6 - 8 have a bug where this returns false.
var undefinedIfNoSparseBug = canDistinguishSparseFromUndefined ? undefined : { valueOf: function () { return 0; } };
var createArrayLikeFromArray = function createArrayLikeFromArray(arr) {
var o = {};
for (var i = 0; i < arr.length; i += 1) {
if (i in arr) {
o[i] = arr[i];
}
}
o.length = arr.length;
return o;
};
var getTestArr = function () {
var arr = [0, false, null, 'hej', true, undefinedIfNoSparseBug, 3, 2];
delete arr[6];
return arr;
};
module.exports = function (findLast, t) {
forEach(v.nonArrays, function (nonArray) {
if (nonArray != null) { // eslint-disable-line eqeqeq
t.equal(
findLast(nonArray, function () { return true; }),
nonArray.length > 0 ? nonArray[nonArray.length - 1] : undefined,
inspect(nonArray) + ' is not an array'
);
}
});
t.test('throws on a non-callable predicate', function (st) {
forEach(v.nonFunctions, function (nonFunction) {
st['throws'](
function () { findLast([], nonFunction); },
TypeError,
inspect(nonFunction) + ' is not a Function'
);
});
st.end();
});
t.test('passes the correct values to the callback', function (st) {
st.plan(5);
var expectedValue = {};
var arr = [expectedValue];
var context = {};
findLast(arr, function (value, key, list) {
st.equal(arguments.length, 3);
st.equal(value, expectedValue, 'first argument is the value');
st.equal(key, 0, 'second argument is the index');
st.equal(list, arr, 'third argument is the array being iterated');
st.equal(this, context, 'receiver is the expected value');
return true;
}, context);
st.end();
});
t.test('does not visit elements added to the array after it has begun', function (st) {
st.plan(2);
var arr = [1, 2, 3];
var i = 0;
findLast(arr, function (a) {
i += 1;
arr.push(a + 3);
return i > 3;
});
st.deepEqual(arr, [1, 2, 3, 6, 5, 4], 'array has received 3 new elements');
st.equal(i, 3, 'findLast callback only called thrice');
st.end();
});
t.test('does not visit elements deleted from the array after it has begun', function (st) {
var arr = [1, 2, 3];
var actual = [];
findLast(arr, function (x, i) {
actual.push([i, x]);
delete arr[1];
return false;
});
st.deepEqual(actual, [[2, 3], [1, undefined], [0, 1]]);
st.end();
});
t.test('sets the right context when given none', function (st) {
var context;
findLast([1], function () { context = this; });
st.equal(context, global, 'receiver is global object in sloppy mode');
st.test('strict mode', { skip: !hasStrictMode }, function (sst) {
findLast([1], function () {
'use strict';
context = this;
});
sst.equal(context, undefined, 'receiver is undefined in strict mode');
sst.end();
});
st.end();
});
t.test('empty array', function (st) {
st.equal(findLast([], trueThunk), undefined, 'true thunk callback yields undefined');
st.equal(findLast([], falseThunk), undefined, 'false thunk callback yields undefined');
var counter = 0;
var callback = function () { counter += 1; };
findLast([], callback);
st.equal(counter, 0, 'counter is not incremented');
st.end();
});
t.equal(findLast([1, 2, 3], trueThunk), 3, 'returns last item if findLast callback returns true');
t.equal(findLast([1, 2, 3], falseThunk), undefined, 'returns undefined if no callback returns true');
t.test('stopping after N elements', function (st) {
st.test('no context', function (sst) {
var actual = {};
var count = 0;
findLast(getTestArr(), function (obj, index) {
actual[index] = obj;
count += 1;
return count === 4;
});
sst.deepEqual(actual, { 4: true, 5: undefinedIfNoSparseBug, 6: undefined, 7: 2 });
sst.end();
});
st.test('with context', function (sst) {
var actual = {};
var context = { actual: actual };
var count = 0;
findLast(getTestArr(), function (obj, index) {
this.actual[index] = obj;
count += 1;
return count === 4;
}, context);
sst.deepEqual(actual, { 4: true, 5: undefinedIfNoSparseBug, 6: undefined, 7: 2 });
sst.end();
});
st.test('arraylike, no context', function (sst) {
var actual = {};
var count = 0;
findLast(createArrayLikeFromArray(getTestArr()), function (obj, index) {
actual[index] = obj;
count += 1;
return count === 4;
});
sst.deepEqual(actual, { 4: true, 5: undefinedIfNoSparseBug, 6: undefined, 7: 2 });
sst.end();
});
st.test('arraylike, context', function (sst) {
var actual = {};
var count = 0;
var context = { actual: actual };
findLast(createArrayLikeFromArray(getTestArr()), function (obj, index) {
this.actual[index] = obj;
count += 1;
return count === 4;
}, context);
sst.deepEqual(actual, { 4: true, 5: undefinedIfNoSparseBug, 6: undefined, 7: 2 });
sst.end();
});
st.end();
});
t.test('list arg boxing', function (st) {
st.plan(3);
findLast('bar', function (item, index, list) {
st.equal(item, 'r', 'last letter matches');
st.equal(typeof list, 'object', 'primitive list arg is boxed');
st.equal(Object.prototype.toString.call(list), '[object String]', 'boxed list arg is a String');
return true;
});
st.end();
});
t.test('array altered during loop', function (st) {
var arr = ['Shoes', 'Car', 'Bike'];
var results = [];
findLast(arr, function (kValue) {
if (results.length === 0) {
arr.splice(1, 1);
}
results.push(kValue);
});
st.equal(results.length, 3, 'predicate called three times');
st.deepEqual(results, ['Bike', 'Bike', 'Shoes']);
results = [];
arr = ['Skateboard', 'Barefoot'];
findLast(arr, function (kValue) {
if (results.length === 0) {
arr.push('Motorcycle');
arr[0] = 'Magic Carpet';
}
results.push(kValue);
});
st.equal(results.length, 2, 'predicate called twice');
st.deepEqual(results, ['Barefoot', 'Magic Carpet']);
st.end();
});
t.test('maximum index', function (st) {
// https://github.com/tc39/test262/pull/3775
var arrayLike = { length: Number.MAX_VALUE };
var calledWithIndex = [];
findLast(arrayLike, function (_, index) {
calledWithIndex.push(index);
return true;
});
st.deepEqual(calledWithIndex, [maxSafeInteger - 1], 'predicate invoked once');
st.end();
});
};
Zerion Mini Shell 1.0