[libcxx-commits] [libcxx] [libc++] Refactor the tests for [iterator.range] (PR #67496)
via libcxx-commits
libcxx-commits at lists.llvm.org
Tue Sep 26 15:27:01 PDT 2023
llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-libcxx
<details>
<summary>Changes</summary>
The tests were a bit of a mess -- the testing coverage wasn't bad but it was extremely difficult to see what was being tested and where. I split up the tests to make them easier to audit for completeness and did such an audit, adding a few missing tests (e.g. the conditional noexcept-ness of std::cbegin and std::cend). I also audited the synopsis and adjusted it where it needed to be adjusted.
This patch is in preparation of fixing #<!-- -->67471.
---
Patch is 34.42 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/67496.diff
8 Files Affected:
- (modified) libcxx/include/iterator (+19-19)
- (added) libcxx/test/std/iterators/iterator.range/begin-end.adl.pass.cpp (+93)
- (added) libcxx/test/std/iterators/iterator.range/begin-end.array.pass.cpp (+87)
- (added) libcxx/test/std/iterators/iterator.range/begin-end.container.pass.cpp (+131)
- (added) libcxx/test/std/iterators/iterator.range/begin-end.initializer_list.pass.cpp (+46)
- (removed) libcxx/test/std/iterators/iterator.range/begin-end.pass.cpp (-282)
- (modified) libcxx/test/std/language.support/support.initlist/support.initlist.range/begin_end.pass.cpp (+46-39)
- (modified) libcxx/utils/data/ignore_format.txt (-2)
``````````diff
diff --git a/libcxx/include/iterator b/libcxx/include/iterator
index 42843781ebbfaa2..36fca48a03bbb60 100644
--- a/libcxx/include/iterator
+++ b/libcxx/include/iterator
@@ -634,25 +634,25 @@ public:
bool failed() const noexcept;
};
-template <class C> constexpr auto begin(C& c) -> decltype(c.begin());
-template <class C> constexpr auto begin(const C& c) -> decltype(c.begin());
-template <class C> constexpr auto end(C& c) -> decltype(c.end());
-template <class C> constexpr auto end(const C& c) -> decltype(c.end());
-template <class T, size_t N> constexpr T* begin(T (&array)[N]);
-template <class T, size_t N> constexpr T* end(T (&array)[N]);
-
-template <class C> auto constexpr cbegin(const C& c) -> decltype(std::begin(c)); // C++14
-template <class C> auto constexpr cend(const C& c) -> decltype(std::end(c)); // C++14
-template <class C> auto constexpr rbegin(C& c) -> decltype(c.rbegin()); // C++14
-template <class C> auto constexpr rbegin(const C& c) -> decltype(c.rbegin()); // C++14
-template <class C> auto constexpr rend(C& c) -> decltype(c.rend()); // C++14
-template <class C> constexpr auto rend(const C& c) -> decltype(c.rend()); // C++14
-template <class E> reverse_iterator<const E*> constexpr rbegin(initializer_list<E> il); // C++14
-template <class E> reverse_iterator<const E*> constexpr rend(initializer_list<E> il); // C++14
-template <class T, size_t N> reverse_iterator<T*> constexpr rbegin(T (&array)[N]); // C++14
-template <class T, size_t N> reverse_iterator<T*> constexpr rend(T (&array)[N]); // C++14
-template <class C> constexpr auto crbegin(const C& c) -> decltype(std::rbegin(c)); // C++14
-template <class C> constexpr auto crend(const C& c) -> decltype(std::rend(c)); // C++14
+template <class C> constexpr auto begin(C& c) -> decltype(c.begin()); // constexpr since C++17
+template <class C> constexpr auto begin(const C& c) -> decltype(c.begin()); // constexpr since C++17
+template <class C> constexpr auto end(C& c) -> decltype(c.end()); // constexpr since C++17
+template <class C> constexpr auto end(const C& c) -> decltype(c.end()); // constexpr since C++17
+template <class T, size_t N> constexpr T* begin(T (&array)[N]) noexcept; // constexpr since C++14
+template <class T, size_t N> constexpr T* end(T (&array)[N]) noexcept; // constexpr since C++14
+
+template <class C> constexpr auto cbegin(const C& c) -> decltype(std::begin(c)); // C++14
+template <class C> constexpr auto cend(const C& c) -> decltype(std::end(c)); // C++14
+template <class C> constexpr auto rbegin(C& c) -> decltype(c.rbegin()); // C++14, constexpr since C++17
+template <class C> constexpr auto rbegin(const C& c) -> decltype(c.rbegin()); // C++14, constexpr since C++17
+template <class C> constexpr auto rend(C& c) -> decltype(c.rend()); // C++14, constexpr since C++17
+template <class C> constexpr auto rend(const C& c) -> decltype(c.rend()); // C++14, constexpr since C++17
+template <class E> constexpr reverse_iterator<const E*> rbegin(initializer_list<E> il); // C++14, constexpr since C++17
+template <class E> constexpr reverse_iterator<const E*> rend(initializer_list<E> il); // C++14, constexpr since C++17
+template <class T, size_t N> constexpr reverse_iterator<T*> rbegin(T (&array)[N]); // C++14, constexpr since C++17
+template <class T, size_t N> constexpr reverse_iterator<T*> rend(T (&array)[N]); // C++14, constexpr since C++17
+template <class C> constexpr auto crbegin(const C& c) -> decltype(std::rbegin(c)); // C++14, constexpr since C++17
+template <class C> constexpr auto crend(const C& c) -> decltype(std::rend(c)); // C++14, constexpr since C++17
// 24.8, container access:
template <class C> constexpr auto size(const C& c) -> decltype(c.size()); // C++17
diff --git a/libcxx/test/std/iterators/iterator.range/begin-end.adl.pass.cpp b/libcxx/test/std/iterators/iterator.range/begin-end.adl.pass.cpp
new file mode 100644
index 000000000000000..c55655c47a61301
--- /dev/null
+++ b/libcxx/test/std/iterators/iterator.range/begin-end.adl.pass.cpp
@@ -0,0 +1,93 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03
+
+// Make sure that std::cbegin(x) effectively calls std::as_const(x).begin(), not x.cbegin().
+//
+// Also make sure that we don't get hijacked by ADL, see https://llvm.org/PR28927.
+
+#include <cassert>
+#include <iterator>
+
+#include "test_macros.h"
+
+struct ArrayHijacker {
+ friend constexpr int begin(ArrayHijacker (&)[3]) { return 42; }
+ friend constexpr int end(ArrayHijacker (&)[3]) { return 42; }
+ friend constexpr int begin(const ArrayHijacker (&)[3]) { return 42; }
+ friend constexpr int end(const ArrayHijacker (&)[3]) { return 42; }
+};
+
+struct ContainerHijacker {
+ int* a_;
+ constexpr int* begin() const { return a_; }
+ constexpr int* end() const { return a_ + 3; }
+ constexpr int* rbegin() const { return a_; }
+ constexpr int* rend() const { return a_ + 3; }
+ friend constexpr int begin(ContainerHijacker&) { return 42; }
+ friend constexpr int end(ContainerHijacker&) { return 42; }
+ friend constexpr int begin(const ContainerHijacker&) { return 42; }
+ friend constexpr int end(const ContainerHijacker&) { return 42; }
+ friend constexpr int cbegin(ContainerHijacker&) { return 42; }
+ friend constexpr int cend(ContainerHijacker&) { return 42; }
+ friend constexpr int cbegin(const ContainerHijacker&) { return 42; }
+ friend constexpr int cend(const ContainerHijacker&) { return 42; }
+ friend constexpr int rbegin(ContainerHijacker&) { return 42; }
+ friend constexpr int rend(ContainerHijacker&) { return 42; }
+ friend constexpr int rbegin(const ContainerHijacker&) { return 42; }
+ friend constexpr int rend(const ContainerHijacker&) { return 42; }
+ friend constexpr int crbegin(ContainerHijacker&) { return 42; }
+ friend constexpr int crend(ContainerHijacker&) { return 42; }
+ friend constexpr int crbegin(const ContainerHijacker&) { return 42; }
+ friend constexpr int crend(const ContainerHijacker&) { return 42; }
+};
+
+TEST_CONSTEXPR_CXX17 bool test() {
+ {
+ ArrayHijacker a[3] = {};
+ assert(begin(a) == 42);
+ assert(end(a) == 42);
+ assert(std::begin(a) == a);
+ assert(std::end(a) == a + 3);
+#if TEST_STD_VER > 11
+ assert(std::cbegin(a) == a);
+ assert(std::cend(a) == a + 3);
+ assert(std::rbegin(a).base() == a + 3);
+ assert(std::rend(a).base() == a);
+ assert(std::crbegin(a).base() == a + 3);
+ assert(std::crend(a).base() == a);
+#endif
+ }
+ {
+ int a[3] = {};
+ ContainerHijacker c{a};
+ assert(begin(c) == 42);
+ assert(end(c) == 42);
+ assert(std::begin(c) == a);
+ assert(std::end(c) == a + 3);
+#if TEST_STD_VER > 11
+ assert(std::cbegin(c) == a);
+ assert(std::cend(c) == a + 3);
+ assert(std::rbegin(c) == a);
+ assert(std::rend(c) == a + 3);
+ assert(std::crbegin(c) == a);
+ assert(std::crend(c) == a + 3);
+#endif
+ }
+ return true;
+}
+
+int main(int, char**) {
+ test();
+#if TEST_STD_VER >= 17
+ static_assert(test());
+#endif
+
+ return 0;
+}
diff --git a/libcxx/test/std/iterators/iterator.range/begin-end.array.pass.cpp b/libcxx/test/std/iterators/iterator.range/begin-end.array.pass.cpp
new file mode 100644
index 000000000000000..478d0a1ec790495
--- /dev/null
+++ b/libcxx/test/std/iterators/iterator.range/begin-end.array.pass.cpp
@@ -0,0 +1,87 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03
+
+// <iterator>
+//
+// template <class T, size_t N> constexpr T* begin(T (&array)[N]) noexcept; // constexpr since C++14
+// template <class T, size_t N> constexpr T* end(T (&array)[N]) noexcept; // constexpr since C++14
+//
+// template <class T, size_t N> constexpr reverse_iterator<T*> rbegin(T (&array)[N]); // C++14, constexpr since C++17
+// template <class T, size_t N> constexpr reverse_iterator<T*> rend(T (&array)[N]); // C++14, constexpr since C++17
+
+#include <cassert>
+#include <iterator>
+
+#include "test_macros.h"
+
+TEST_CONSTEXPR_CXX14 bool test() {
+ int a[] = {1, 2, 3};
+ const auto& ca = a;
+
+ // std::begin(T (&)[N]) / std::end(T (&)[N])
+ {
+ ASSERT_NOEXCEPT(std::begin(a));
+ ASSERT_SAME_TYPE(decltype(std::begin(a)), int*);
+ assert(std::begin(a) == a);
+
+ ASSERT_NOEXCEPT(std::end(a));
+ ASSERT_SAME_TYPE(decltype(std::end(a)), int*);
+ assert(std::end(a) == a + 3);
+
+ // kind of overkill since it follows from the definition, but worth testing
+ ASSERT_NOEXCEPT(std::begin(ca));
+ ASSERT_SAME_TYPE(decltype(std::begin(ca)), const int*);
+ assert(std::begin(ca) == ca);
+
+ ASSERT_NOEXCEPT(std::end(ca));
+ ASSERT_SAME_TYPE(decltype(std::end(ca)), const int*);
+ assert(std::end(ca) == ca + 3);
+ }
+
+ return true;
+}
+
+TEST_CONSTEXPR_CXX17 bool test_r() {
+ int a[] = {1, 2, 3};
+ const auto& ca = a;
+
+#if TEST_STD_VER >= 14
+ // std::rbegin(T (&)[N]) / std::rend(T (&)[N])
+ {
+ ASSERT_SAME_TYPE(decltype(std::rbegin(a)), std::reverse_iterator<int*>);
+ assert(std::rbegin(a).base() == a + 3);
+
+ ASSERT_SAME_TYPE(decltype(std::rend(a)), std::reverse_iterator<int*>);
+ assert(std::rend(a).base() == a);
+
+ // kind of overkill since it follows from the definition, but worth testing
+ ASSERT_SAME_TYPE(decltype(std::rbegin(ca)), std::reverse_iterator<const int*>);
+ assert(std::rbegin(ca).base() == ca + 3);
+
+ ASSERT_SAME_TYPE(decltype(std::rend(ca)), std::reverse_iterator<const int*>);
+ assert(std::rend(ca).base() == ca);
+ }
+#endif
+
+ return true;
+}
+
+int main(int, char**) {
+ test();
+ test_r();
+#if TEST_STD_VER >= 14
+ static_assert(test(), "");
+#endif
+#if TEST_STD_VER >= 17
+ static_assert(test_r(), "");
+#endif
+
+ return 0;
+}
diff --git a/libcxx/test/std/iterators/iterator.range/begin-end.container.pass.cpp b/libcxx/test/std/iterators/iterator.range/begin-end.container.pass.cpp
new file mode 100644
index 000000000000000..51e8e4994ebe15b
--- /dev/null
+++ b/libcxx/test/std/iterators/iterator.range/begin-end.container.pass.cpp
@@ -0,0 +1,131 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03
+
+// <iterator>
+//
+// template <class C> constexpr auto begin(C& c) -> decltype(c.begin()); // constexpr since C++17
+// template <class C> constexpr auto begin(const C& c) -> decltype(c.begin()); // constexpr since C++17
+// template <class C> constexpr auto end(C& c) -> decltype(c.end()); // constexpr since C++17
+// template <class C> constexpr auto end(const C& c) -> decltype(c.end()); // constexpr since C++17
+//
+// template <class C> constexpr auto cbegin(const C& c) -> decltype(std::begin(c)); // C++14
+// template <class C> constexpr auto cend(const C& c) -> decltype(std::end(c)); // C++14
+// template <class C> constexpr auto rbegin(C& c) -> decltype(c.rbegin()); // C++14, constexpr since C++17
+// template <class C> constexpr auto rbegin(const C& c) -> decltype(c.rbegin()); // C++14, constexpr since C++17
+// template <class C> constexpr auto rend(C& c) -> decltype(c.rend()); // C++14, constexpr since C++17
+// template <class C> constexpr auto rend(const C& c) -> decltype(c.rend()); // C++14, constexpr since C++17
+// template <class C> constexpr auto crbegin(const C& c) -> decltype(std::rbegin(c)); // C++14, constexpr since C++17
+// template <class C> constexpr auto crend(const C& c) -> decltype(std::rend(c)); // C++14, constexpr since C++17
+
+#include <array>
+#include <cassert>
+#include <iterator>
+#include <list>
+#include <vector>
+
+#include "test_macros.h"
+
+template <typename C,
+ typename Iterator = typename C::iterator,
+ typename ConstIterator = typename C::const_iterator,
+ typename ReverseIterator = typename C::reverse_iterator,
+ typename ConstReverseIterator = typename C::const_reverse_iterator>
+TEST_CONSTEXPR_CXX17 bool test() {
+ C c = {1, 2, 3};
+ const C& cc = c;
+
+ // std::begin(C& c) / std::end(C& c)
+ {
+ ASSERT_SAME_TYPE(decltype(std::begin(c)), Iterator);
+ assert(std::begin(c) == c.begin());
+
+ ASSERT_SAME_TYPE(decltype(std::end(c)), Iterator);
+ assert(std::end(c) == c.end());
+ }
+
+ // std::begin(C const& c) / std::end(C const& c)
+ {
+ ASSERT_SAME_TYPE(decltype(std::begin(cc)), ConstIterator);
+ assert(std::begin(cc) == cc.begin());
+
+ ASSERT_SAME_TYPE(decltype(std::end(cc)), ConstIterator);
+ assert(std::end(cc) == cc.end());
+ }
+
+#if TEST_STD_VER >= 14
+ // std::cbegin(C const&) / std::cend(C const&)
+ {
+ ASSERT_SAME_TYPE(decltype(std::cbegin(cc)), ConstIterator);
+ static_assert(noexcept(std::cbegin(cc)) == noexcept(std::begin(cc)), "");
+ assert(std::cbegin(cc) == std::begin(cc));
+
+ ASSERT_SAME_TYPE(decltype(std::cend(cc)), ConstIterator);
+ static_assert(noexcept(std::cend(cc)) == noexcept(std::end(cc)), "");
+ assert(std::cend(cc) == std::end(cc));
+
+ // kind of overkill, but whatever
+ ASSERT_SAME_TYPE(decltype(std::cbegin(c)), ConstIterator);
+ static_assert(noexcept(std::cbegin(c)) == noexcept(std::begin(cc)), "");
+ assert(std::cbegin(c) == std::begin(cc));
+
+ ASSERT_SAME_TYPE(decltype(std::cend(c)), ConstIterator);
+ static_assert(noexcept(std::cend(c)) == noexcept(std::end(cc)), "");
+ assert(std::cend(c) == std::end(cc));
+ }
+
+ // std::rbegin(C& c) / std::rend(C& c)
+ {
+ ASSERT_SAME_TYPE(decltype(std::rbegin(c)), ReverseIterator);
+ assert(std::rbegin(c) == c.rbegin());
+
+ ASSERT_SAME_TYPE(decltype(std::rend(c)), ReverseIterator);
+ assert(std::rend(c) == c.rend());
+ }
+
+ // std::rbegin(C const&) / std::rend(C const&)
+ {
+ ASSERT_SAME_TYPE(decltype(std::rbegin(cc)), ConstReverseIterator);
+ assert(std::rbegin(cc) == cc.rbegin());
+
+ ASSERT_SAME_TYPE(decltype(std::rend(cc)), ConstReverseIterator);
+ assert(std::rend(cc) == cc.rend());
+ }
+
+ // std::crbegin(C const&) / std::crend(C const&)
+ {
+ ASSERT_SAME_TYPE(decltype(std::crbegin(cc)), ConstReverseIterator);
+ assert(std::crbegin(cc) == std::rbegin(cc));
+
+ ASSERT_SAME_TYPE(decltype(std::crend(cc)), ConstReverseIterator);
+ assert(std::crend(cc) == std::rend(cc));
+
+ // kind of overkill, but whatever
+ ASSERT_SAME_TYPE(decltype(std::crbegin(c)), ConstReverseIterator);
+ assert(std::crbegin(c) == std::rbegin(cc));
+
+ ASSERT_SAME_TYPE(decltype(std::crend(c)), ConstReverseIterator);
+ assert(std::crend(c) == std::rend(cc));
+ }
+#endif // TEST_STD_VER >= 14
+
+ return true;
+}
+
+int main(int, char**) {
+ test<std::array<int, 3>>();
+ test<std::list<int>>();
+ test<std::vector<int>>();
+
+#if TEST_STD_VER >= 17
+ static_assert(test<std::array<int, 3>>());
+#endif
+
+ return 0;
+}
diff --git a/libcxx/test/std/iterators/iterator.range/begin-end.initializer_list.pass.cpp b/libcxx/test/std/iterators/iterator.range/begin-end.initializer_list.pass.cpp
new file mode 100644
index 000000000000000..2df9283b0576dfd
--- /dev/null
+++ b/libcxx/test/std/iterators/iterator.range/begin-end.initializer_list.pass.cpp
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11
+
+// <iterator>
+//
+// Note that begin and end are tested in libcxx/test/std/language.support/support.initlist/support.initlist.range/begin_end.pass.cpp
+//
+// template <class E> constexpr reverse_iterator<const E*> rbegin(initializer_list<E> il); // C++14, constexpr since C++17
+// template <class E> constexpr reverse_iterator<const E*> rend(initializer_list<E> il); // C++14, constexpr since C++17
+
+#include <cassert>
+#include <initializer_list>
+#include <iterator>
+
+#include "test_macros.h"
+
+TEST_CONSTEXPR_CXX17 bool test() {
+ std::initializer_list<int> il = {1, 2, 3};
+ ASSERT_SAME_TYPE(decltype(std::rbegin(il)), std::reverse_iterator<const int*>);
+ ASSERT_SAME_TYPE(decltype(std::rend(il)), std::reverse_iterator<const int*>);
+ assert(std::rbegin(il).base() == il.end());
+ assert(std::rend(il).base() == il.begin());
+
+ const auto& cil = il;
+ ASSERT_SAME_TYPE(decltype(std::rbegin(cil)), std::reverse_iterator<const int*>);
+ ASSERT_SAME_TYPE(decltype(std::rend(cil)), std::reverse_iterator<const int*>);
+ assert(std::rbegin(cil).base() == il.end());
+ assert(std::rend(cil).base() == il.begin());
+ return true;
+}
+
+int main(int, char**) {
+ test();
+#if TEST_STD_VER >= 17
+ static_assert(test());
+#endif
+
+ return 0;
+}
diff --git a/libcxx/test/std/iterators/iterator.range/begin-end.pass.cpp b/libcxx/test/std/iterators/iterator.range/begin-end.pass.cpp
deleted file mode 100644
index e723b0faf3b8015..000000000000000
--- a/libcxx/test/std/iterators/iterator.range/begin-end.pass.cpp
+++ /dev/null
@@ -1,282 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// UNSUPPORTED: c++03
-
-// <iterator>
-// template <class C> constexpr auto begin(C& c) -> decltype(c.begin());
-// template <class C> constexpr auto begin(const C& c) -> decltype(c.begin());
-// template <class C> constexpr auto cbegin(const C& c) -> decltype(std::begin(c)); // C++14
-// template <class C> constexpr auto cend(const C& c) -> decltype(std::end(c)); // C++14
-// template <class C> constexpr auto end (C& c) -> decltype(c.end());
-// template <class C> constexpr auto end (const C& c) -> decltype(c.end());
-// template <class E> constexpr reverse_iterator<const E*> rbegin(initializer_list<E> il);
-// template <class E> constexpr reverse_iterator<const E*> rend (initializer_list<E> il);
-//
-// template <class C> auto constexpr rbegin(C& c) -> decltype(c.rbegin()); // C++14
-// template <class C> auto constexpr rbegin(const C& c) -> decltype(c.rbegin()); // C++14
-// template <class C> auto constexpr rend(C& c) -> decltype(c.rend()); // C++14
-// template <class C> constexpr auto rend(const C& c) -> decltype(c.rend()); // C++14
-// template <class T, size_t N> reverse_iterator<T*> constexpr rbegin(T (&array)[N]); // C++14
-// template <class T, size_t N> reverse_iterator<T*> constexpr rend(T (&array)[N]); // C++14
-// template <class C> constexpr auto crbegin(const C& c) -> decltype(std::rbegin(c)); // C++14
-// template <class C> constexpr auto crend(const C& c) -> decltype(std::rend(c)); // C++14
-//
-// All of these are constexpr in C++17
-
-#include <array>
-#include <cas...
[truncated]
``````````
</details>
https://github.com/llvm/llvm-project/pull/67496
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