1 files changed, 52 insertions, 0 deletions
diff --git a/libcxx/test/support/counting_predicates.h b/libcxx/test/support/counting_predicates.h
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+++ b/libcxx/test/support/counting_predicates.h
@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef TEST_SUPPORT_COUNTING_PREDICATES_H
+#define TEST_SUPPORT_COUNTING_PREDICATES_H
+
+#include <cstddef>
+
+template <typename Predicate, typename Arg>
+struct unary_counting_predicate {
+public:
+    typedef Arg argument_type;
+    typedef bool result_type;
+
+    unary_counting_predicate(Predicate p) : p_(p), count_(0) {}
+    ~unary_counting_predicate() {}
+
+    bool operator () (const Arg &a) const { ++count_; return p_(a); }
+    size_t count() const { return count_; }
+    void reset() { count_ = 0; }
+
+private:
+    Predicate p_;
+    mutable size_t count_;
+};
+
+
+template <typename Predicate, typename Arg1, typename Arg2=Arg1>
+struct binary_counting_predicate {
+public:
+    typedef Arg1 first_argument_type;
+    typedef Arg2 second_argument_type;
+    typedef bool result_type;
+
+    binary_counting_predicate ( Predicate p ) : p_(p), count_(0) {}
+    ~binary_counting_predicate() {}
+
+    bool operator () (const Arg1 &a1, const Arg2 &a2) const { ++count_; return p_(a1, a2); }
+    size_t count() const { return count_; }
+    void reset() { count_ = 0; }
+
+private:
+    Predicate p_;
+    mutable size_t count_;
+};
+
+#endif // TEST_SUPPORT_COUNTING_PREDICATES_H