var a, b, c, d, col, otherCol;
module('Backbone.Shard', {
    setup: function() {
        a = new Backbone.Model({data: 'a'});
        b = new Backbone.Model({data: 'b'});
        c = new Backbone.Model({data: 'c'});
        d = new Backbone.Model({data: 'd'});
        col = new Backbone.Collection([a, b, c, d]);
        otherCol = new Backbone.Collection();
    }
});
test('Sensible filter function, collection is prepopulated', function() {
    var shard = new Backbone.Shard({
        collection: col,
        filter: function(model) { return _(['a', 'c']).contains(model.get('data')); }
    });
    equal(shard.size(), 2, 'shard has 2 items');
    equal(shard.first(), a, 'a is the first element');
    equal(shard.last(), c, 'c is the last element');
});
test('Sensible filter function, collection populated dynamically', function() {
    var shard = new Backbone.Shard({
        collection: otherCol,
        filter: function(model) { return _(['a', 'c']).contains(model.get('data')); }
    });
    var additions = 0;
    var removals = 0;
    var resets = 0;
    shard.on('add', function() {
        additions++;
    }).on('remove', function() {
        removals++;
    }).on('reset', function() {
        resets++;
    });
    otherCol.add([a, b, c, d]);
    equal(additions, 2, 'adding models matching shard filter to collection triggers add events');
    equal(shard.size(), 2, '... and the shard has 2 items');
    otherCol.remove([b, d]);
    equal(removals, 0, 'removing models not matching shard filter from collection does not trigger remove events');
    equal(shard.size(), 2, '... and the shard has 2 items');
    otherCol.remove([a, c]);
    equal(removals, 2, 'removing models matching shard filter from collection triggers remove events');
    equal(shard.size(), 0, '... and the shard is empty');
    otherCol.reset([a, b, c, d]);
    equal(resets, 1, 'resetting collection triggers reset events');
    equal(shard.size(), 2, '... and the shard has 2 items');
});