2015-01-04 19:40:09 +11:00

48 lines
992 B
JavaScript

// should have a length of 1
assert.equal(Array.prototype.findIndex.length, 1);
// should handle basic case
assert.equal([1, 2, 3].findIndex(function(v) {
return v * v === 4;
}), 1);
// should handle arrow functions
assert.equal([1, 2, 3].findIndex(v => v * v === 4), 1);
// should return -1 when not found
assert.equal([1, 2, 3].findIndex(v => v > 10), -1);
// should return first match
assert.equal([2, 2, 3].findIndex(v => v * v === 4), 0);
// should handle custom objects
assert.equal(Array.prototype.findIndex.call({
'length': 2,
'0': false,
'1': true
}, v => v), 1);
var lengthCalls = 0;
var itemCalls = 0;
var callbackCalls = 0;
var object = {
length: {
valueOf() {
lengthCalls++;
return 3;
}
},
get 2() {
itemCalls++;
return 'a';
}
};
assert.equal(Array.prototype.findIndex.call(object, (v) => {
callbackCalls++;
return v === 'a';
}), 2);
assert.equal(lengthCalls, 1);
assert.equal(itemCalls, 1);
assert.equal(callbackCalls, 3);