Fixing more issues with template type diffing

1) Print qualifiers for templates with zero arguments
2) Add a few more tests for the template type diffing refactoring.
Specifically, PR24587 has been fixed and has a test case from
http://reviews.llvm.org/D15384
3) Adds asserts to check the DiffTree is in correct state when moving nodes
4) Rename the field FromType and ToType since it is heavily used within
member functions.

llvm-svn: 257870

1 files changed, 56 insertions, 0 deletions

diff --git a/clang/test/Misc/diag-template-diffing.cpp b/clang/test/Misc/diag-template-diffing.cpp
index cf850a5fc05..70d5e7c8709 100644
--- a/clang/test/Misc/diag-template-diffing.cpp
+++ b/clang/test/Misc/diag-template-diffing.cpp
@@ -1371,6 +1371,62 @@ C<int &, x> c2 = C<int>();
 // CHECK-ELIDE-TREE:     [(default) 11 != x]>
 }
 
+namespace default_args {
+  template <int x, int y = 1+1, int z = 2>
+  class A {};
+
+  void foo(A<0> &M) {
+    // CHECK-ELIDE-NOTREE: no viable conversion from 'A<[...], (default) 1 + 1 aka 2, (default) 2>' to 'A<[...], 0, 0>'
+    A<0, 0, 0> N = M;
+
+    // CHECK-ELIDE-NOTREE: no viable conversion from 'A<[2 * ...], (default) 2>' to 'A<[2 * ...], 0>'
+    A<0, 2, 0> N2 = M;
+  }
+}
+
+namespace DefaultNonTypeArgWithDependentType {
+// We used to crash diffing integer template arguments when the argument type
+// is dependent and default arguments were used.
+template <typename SizeType = int, SizeType = 0> struct A {};
+template <typename R = A<>> R bar();
+A<> &foo() { return bar(); }
+// CHECK-ELIDE-NOTREE: error: non-const lvalue reference to type 'A<[2 * ...]>' cannot bind to a temporary of type 'A<[2 * ...]>'
+// CHECK-NOELIDE-NOTREE: error: non-const lvalue reference to type 'A<int, 0>' cannot bind to a temporary of type 'A<int, 0>'
+}
+
+namespace PR24587 {
+template <typename T, T v>
+struct integral_constant {};
+
+auto false_ = integral_constant<bool, false> {};
+
+template <typename T>
+void f(T, decltype(false_));
+
+void run() {
+  f(1, integral_constant<bool, true>{});
+}
+// CHECK-ELIDE-NOTREE: error: no matching function for call to 'f'
+// CHECK-ELIDE-NOTREE: note: candidate function [with T = int] not viable: no known conversion from 'integral_constant<[...], true>' to 'integral_constant<[...], false>' for 2nd argument
+}
+
+namespace ZeroArgs {
+template <int N = 0> class A {};
+template <class T = A<>> class B {};
+A<1> a1 = A<>();
+A<> a2 = A<1>();
+B<> b1 = B<int>();
+B<int> b2 = B<>();
+B<> b3 = B<const A<>>();
+B<const A<>> b4 = B<>();
+// CHECK-ELIDE-NOTREE: error: no viable conversion from 'A<(default) 0>' to 'A<1>'
+// CHECK-ELIDE-NOTREE: error: no viable conversion from 'A<1>' to 'A<(default) 0>'
+// CHECK-ELIDE-NOTREE: error: no viable conversion from 'B<int>' to 'B<(default) ZeroArgs::A<0>>'
+// CHECK-ELIDE-NOTREE: error: no viable conversion from 'B<(default) ZeroArgs::A<0>>' to 'B<int>'
+// CHECK-ELIDE-NOTREE: error: no viable conversion from 'B<const A<[...]>>' to 'B<A<[...]>>'
+// CHECK-ELIDE-NOTREE: error: no viable conversion from 'B<A<[...]>>' to 'B<const A<[...]>>'
+}
+
 // CHECK-ELIDE-NOTREE: {{[0-9]*}} errors generated.
 // CHECK-NOELIDE-NOTREE: {{[0-9]*}} errors generated.
 // CHECK-ELIDE-TREE: {{[0-9]*}} errors generated.