folly/futures/test/then_compile_test.rb

   1 #!/usr/bin/env ruby
   2
   3 # cd folly/futures/test && ruby then_compile_test.rb > ThenCompileTest.cpp
   4
   5 # An exercise in combinatorics.
   6 # (ordinary/static function, member function, std::function, lambda)
   7 # X
   8 # returns (Future<R>, R)
   9 # X
  10 # accepts (Try<T>&&, Try<T> const&, Try<T>, T&&, T const&, T, nothing)
  11
  12 def test(*args)
  13   args = args.join(", ")
  14   [
  15   "{Future<B> f = someFuture<A>().then(#{args});}",
  16   #"{Future<B> f = makeFuture(A()).then(#{args}, anExecutor);}",
  17   ]
  18 end
  19
  20 def retval(ret)
  21   {
  22     "Future<B>" => "someFuture<B>()",
  23     "Try<B>" => "Try<B>(B())",
  24     "B" => "B()"
  25   }[ret]
  26 end
  27
  28 return_types = [
  29   "Future<B>",
  30   "B",
  31   #"Try<B>",
  32 ]
  33 param_types = [
  34     "Try<A>&&",
  35     "Try<A> const&",
  36     "Try<A>",
  37     "Try<A>&",
  38     "A&&",
  39     "A const&",
  40     "A",
  41     "A&",
  42     "",
  43   ]
  44
  45 tests = (
  46   return_types.map { |ret|
  47     param_types.map { |param|
  48       if param != "" then
  49         both = "#{ret}, #{param}"
  50         [
  51           ["&aFunction<#{both}>"],
  52           ["&SomeClass::aStaticMethod<#{both}>"],
  53           ["&SomeClass::aMethod<#{both}>", "&anObject"],
  54           ["aStdFunction<#{both}>()"],
  55           ["[&](#{param}){return #{retval(ret)};}"],
  56         ]
  57       else
  58         [["[&](){return #{retval(ret)};}"]]
  59       end
  60     }
  61   }.flatten(2)
  62 ).map {|a| test(a)}.flatten
  63
  64 print <<EOF
  65 // This file is #{"@"}generated by then_compile_test.rb. Do not edit directly.
  66
  67 #include <folly/futures/test/ThenCompileTest.h>
  68
  69 using namespace folly;
  70
  71 TEST(Basic, thenVariants) {
  72   SomeClass anObject;
  73
  74   #{tests.join("\n  ")}
  75 }
  76 EOF