1 files changed, 58 insertions, 0 deletions
diff --git a/src/boost/libs/hana/test/map/fold_left.cpp b/src/boost/libs/hana/test/map/fold_left.cpp
new file mode 100644
index 000000000..558120c9a
--- /dev/null
+++ b/src/boost/libs/hana/test/map/fold_left.cpp
@@ -0,0 +1,58 @@
+// Copyright Louis Dionne 2013-2017
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+
+#include <boost/hana/assert.hpp>
+#include <boost/hana/contains.hpp>
+#include <boost/hana/equal.hpp>
+#include <boost/hana/fold_left.hpp>
+#include <boost/hana/map.hpp>
+#include <boost/hana/permutations.hpp>
+#include <boost/hana/transform.hpp>
+
+#include <laws/base.hpp>
+#include <support/seq.hpp>
+#include <support/minimal_product.hpp>
+namespace hana = boost::hana;
+
+
+template <int i>
+auto key() { return hana::test::ct_eq<i>{}; }
+
+template <int i>
+auto val() { return hana::test::ct_eq<-i>{}; }
+
+template <int i, int j>
+auto p() { return ::minimal_product(key<i>(), val<j>()); }
+
+struct undefined { };
+
+int main() {
+    auto sequence = ::seq;
+
+    // Use pointers to work around a Clang ICE
+    hana::test::_injection<0> f{};
+    auto* fp = &f;
+
+    hana::test::ct_eq<999> state{};
+    auto* statep = &state;
+
+    auto check = [=](auto ...pairs) {
+        auto possible_results = hana::transform(hana::permutations(sequence(pairs...)),
+            [=](auto xs) {
+                return hana::fold_left(xs, *statep, *fp);
+            }
+        );
+
+        BOOST_HANA_CONSTANT_CHECK(hana::contains(
+            possible_results,
+            hana::fold_left(hana::make_map(pairs...), state, f)
+        ));
+    };
+
+    check();
+    check(p<1, 1>());
+    check(p<1, 1>(), p<2, 2>());
+    check(p<1, 1>(), p<2, 2>(), p<3, 3>());
+    check(p<1, 1>(), p<2, 2>(), p<3, 3>(), p<4, 4>());
+}