tests/base_isa_nullable_vt2.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Copyright 2012 Alexandre Terrasa <alexandre@moz-code.org>
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #     http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 import base_minimal
  18
  19 class Something end
  20
  21 class A[T]
  22         type U: nullable Object
  23
  24         fun test(t: nullable T): Bool do
  25                 return t isa U
  26         end
  27 end
  28
  29 class B[T]
  30         super A[T]
  31
  32         redef type U: Bool
  33 end
  34
  35 class C[T]
  36         super A[T]
  37
  38         redef type U: nullable Bool
  39 end
  40
  41 var a = new A[Object]
  42 assert a.test(true)
  43 assert a.test(null)
  44
  45 a = new A[Bool]
  46 assert a.test(true)
  47 assert a.test(null)
  48
  49 var b = new B[Object]
  50 assert not b.test(new Something)
  51 assert b.test(false)
  52 assert not b.test(null)
  53
  54 var c = new C[Object]
  55 assert not c.test(new Something)
  56 assert c.test(false)
  57 assert c.test(null)
  58
  59 true.output