gnome-shell/tests/unit/insertSorted.js
Giovanni Campagna bbdce159fa Util: fix binary search exit condition
The loop can exit with an interval of length one or one of
length zero. In the first case it is correct to check which side
of the interval to return, in the second case no comparison should
be made (since there is only one possible value).
In practice, this usually results in one comparison more than needed,
but in some cases (when the position was past the end of the array),
would call the comparator with undefined.

https://bugzilla.gnome.org/show_bug.cgi?id=666614
2011-12-20 22:44:03 +01:00

77 lines
1.9 KiB
JavaScript

/* -*- mode: js2; js2-basic-offset: 4; indent-tabs-mode: nil -*- */
// Test cases for Util.insertSorted
const JsUnit = imports.jsUnit;
// Needed so that Util can bring some UI stuff
// we don't actually use
const Environment = imports.ui.environment;
Environment.init();
const Util = imports.misc.util;
function assertArrayEquals(errorMessage, array1, array2) {
JsUnit.assertEquals(errorMessage + ' length',
array1.length, array2.length);
for (let j = 0; j < array1.length; j++) {
JsUnit.assertEquals(errorMessage + ' item ' + j,
array1[j], array2[j]);
}
}
function cmp(one, two) {
return one-two;
}
let arrayInt = [1, 2, 3, 5, 6];
Util.insertSorted(arrayInt, 4, cmp);
assertArrayEquals('first test', [1,2,3,4,5,6], arrayInt);
// no comparator, integer sorting is implied
Util.insertSorted(arrayInt, 3);
assertArrayEquals('second test', [1,2,3,3,4,5,6], arrayInt);
let obj1 = { a: 1 };
let obj2 = { a: 2, b: 0 };
let obj3 = { a: 2, b: 1 };
let obj4 = { a: 3 };
function objCmp(one, two) {
return one.a - two.a;
}
let arrayObj = [obj1, obj3, obj4];
// obj2 compares equivalent to obj3, should be
// inserted before
Util.insertSorted(arrayObj, obj2, objCmp);
assertArrayEquals('object test', [obj1, obj2, obj3, obj4], arrayObj);
function checkedCmp(one, two) {
if (typeof one != 'number' ||
typeof two != 'number')
throw new TypeError('Invalid type passed to checkedCmp');
return one-two;
}
let arrayEmpty = [];
// check that no comparisons are made when
// inserting in a empty array
Util.insertSorted(arrayEmpty, 3, checkedCmp);
// Insert at the end and check that we don't
// access past it
Util.insertSorted(arrayEmpty, 4, checkedCmp);
Util.insertSorted(arrayEmpty, 5, checkedCmp);
// Some more insertions
Util.insertSorted(arrayEmpty, 2, checkedCmp);
Util.insertSorted(arrayEmpty, 1, checkedCmp);
assertArrayEquals('checkedCmp test', [1, 2, 3, 4, 5], arrayEmpty);