clang/test/AST/ast-dump-templates.cpp

   1 // RUN: %clang_cc1 -std=c++1z -ast-print %s > %t
   2 // RUN: FileCheck < %t %s -check-prefix=CHECK1
   3 // RUN: FileCheck < %t %s -check-prefix=CHECK2
   4 // RUN: %clang_cc1 -std=c++1z -ast-dump %s | FileCheck --check-prefix=DUMP %s
   5
   6 template <int X, typename Y, int Z = 5>
   7 struct foo {
   8   int constant;
   9   foo() {}
  10   Y getSum() { return Y(X + Z); }
  11 };
  12
  13 template <int A, typename B>
  14 B bar() {
  15   return B(A);
  16 }
  17
  18 void baz() {
  19   int x = bar<5, int>();
  20   int y = foo<5, int>().getSum();
  21   double z = foo<2, double, 3>().getSum();
  22 }
  23
  24 // Template definition - foo
  25 // CHECK1: template <int X, typename Y, int Z = 5> struct foo {
  26 // CHECK2: template <int X, typename Y, int Z = 5> struct foo {
  27
  28 // Template instantiation - foo
  29 // Since the order of instantiation may vary during runs, run FileCheck twice
  30 // to make sure each instantiation is in the correct spot.
  31 // CHECK1: template<> struct foo<5, int, 5> {
  32 // CHECK2: template<> struct foo<2, double, 3> {
  33
  34 // Template definition - bar
  35 // CHECK1: template <int A, typename B> B bar()
  36 // CHECK2: template <int A, typename B> B bar()
  37
  38 // Template instantiation - bar
  39 // CHECK1: template<> int bar<5, int>()
  40 // CHECK2: template<> int bar<5, int>()
  41
  42 // CHECK1-LABEL: template <typename ...T> struct A {
  43 // CHECK1-NEXT:    template <T ...x[3]> struct B {
  44 template <typename ...T> struct A {
  45   template <T ...x[3]> struct B {};
  46 };
  47
  48 // CHECK1-LABEL: template <typename ...T> void f() {
  49 // CHECK1-NEXT:    A<T[3]...> a;
  50 template <typename ...T> void f() {
  51   A<T[3]...> a;
  52 }
  53
  54 namespace test2 {
  55 void func(int);
  56 void func(float);
  57 template<typename T>
  58 void tmpl() {
  59   func(T());
  60 }
  61
  62 // DUMP: UnresolvedLookupExpr {{.*}} <col:3> '<overloaded function type>' lvalue (ADL) = 'func'
  63 }
  64
  65 namespace test3 {
  66   template<typename T> struct A {};
  67   template<typename T> A(T) -> A<int>;
  68   // CHECK1: template <typename T> A(T) -> A<int>;
  69 }
  70
  71 namespace test4 {
  72 template <unsigned X, auto A>
  73 struct foo {
  74   static void fn();
  75 };
  76
  77 // Prints using an "integral" template argument. Test that this correctly
  78 // includes the type for the auto argument and omits it for the fixed
  79 // type/unsigned argument (see
  80 // TemplateParameterList::shouldIncludeTypeForArgument)
  81 // CHECK1: {{^    }}template<> struct foo<0, 0L> {
  82 // CHECK1: {{^    }}void test(){{ }}{
  83 // CHECK1: {{^        }}foo<0, 0 + 0L>::fn();
  84 void test() {
  85   foo<0, 0 + 0L>::fn();
  86 }
  87
  88 // Prints using an "expression" template argument. This renders based on the way
  89 // the user wrote the arguments (including that + expression) - so it's not
  90 // powered by the shouldIncludeTypeForArgument functionality.
  91 // Not sure if this it's intentional that these two specializations are rendered
  92 // differently in this way.
  93 // CHECK1: {{^    }}template<> struct foo<1, 0 + 0L> {
  94 template struct foo<1, 0 + 0L>;
  95 }
  96
  97 namespace test5 {
  98 template<long> void f() {}
  99 void (*p)() = f<0>;
 100 template<unsigned = 0> void f() {}
 101 void (*q)() = f<>;
 102 // Not perfect - this code in the dump would be ambiguous, but it's the best we
 103 // can do to differentiate these two implicit specializations.
 104 // CHECK1: template<> void f<0L>()
 105 // CHECK1: template<> void f<0U>()
 106 }
 107
 108 namespace test6 {
 109 template <class D>
 110 constexpr bool C = true;
 111
 112 template <class Key>
 113 void func() {
 114   C<Key>;
 115 // DUMP:      UnresolvedLookupExpr {{.*}} '<dependent type>' lvalue (no ADL) = 'C'
 116 // DUMP-NEXT: `-TemplateArgument type 'Key'
 117 // DUMP-NEXT:   `-TemplateTypeParmType {{.*}} 'Key' dependent depth 0 index 0
 118 // DUMP-NEXT:     `-TemplateTypeParm {{.*}} 'Key'
 119 }
 120 }