The phrase .contain.all takes a range, all elements of which are expected to appear in the range on the left hand side.
[2, 3, 4].should.contain.all([3]); [2, 3, 4].should.contain.all([4, 3]); [2, 3, 4].should.not.contain.all([3, 4, 5]);
See Implementation
The phrase .contain.all takes a range, all elements of which are expected to appear in the range on the left hand side.