Foo.expects(:bar)
Foo.bar(:abc => 123, :xyz => 987)
# assert Foo.bar was called with a hash that has a key of :abc == 123
Foo.expects(:bar)
Foo.bar(:abc => 123, :xyz => Foo.expects(:bar)
Foo.bar(:abc => 123, :xyz => 987)
# assert Foo.bar was called with a hash that has a key of :abc == 123
Foo.expects(:bar)
Foo.bar(:abc => 123, :xyz =>