Added unit tests, and fixed two bugs: (#53)

* Integer conversion checks in src/wire/read.h
 * Missing "boolean" function in wire::writer and derived types

tests/unit/wire/read.test.cpp

@@ -0,0 +1,107 @@
+// Copyright (c) 2022, The Monero Project
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "framework.test.h"
+
+#include <boost/core/demangle.hpp>
+#include <cstdint>
+#include <limits>
+#include "wire/read.h"
+
+namespace
+{
+  template<typename Target>
+  void test_unsigned_to_unsigned(lest::env& lest_env)
+  {
+    using limit = std::numeric_limits<Target>;
+    static constexpr const auto max =
+      std::numeric_limits<std::uintmax_t>::max();
+    static_assert(limit::is_integer, "expected integer");
+    static_assert(!limit::is_signed, "expected unsigned");
+
+    SETUP("uintmax_t to " + boost::core::demangle(typeid(Target).name()))
+    {
+      EXPECT(Target(0) == wire::integer::cast_unsigned<Target>(std::uintmax_t(0)));
+      EXPECT(limit::max() == wire::integer::cast_unsigned<Target>(std::uintmax_t(limit::max())));
+      if (limit::max() < max)
+      {
+        EXPECT_THROWS_AS(wire::integer::cast_unsigned<Target>(std::uintmax_t(limit::max()) + 1), wire::exception);
+        EXPECT_THROWS_AS(wire::integer::cast_unsigned<Target>(max), wire::exception);
+      }
+    }
+  }
+
+  template<typename Target>
+  void test_signed_to_signed(lest::env& lest_env)
+  {
+    using limit = std::numeric_limits<Target>;
+    static constexpr const auto min =
+      std::numeric_limits<std::intmax_t>::min();
+    static constexpr const auto max =
+      std::numeric_limits<std::intmax_t>::max();
+    static_assert(limit::is_integer, "expected integer");
+    static_assert(limit::is_signed, "expected signed");
+
+    SETUP("intmax_t to " + boost::core::demangle(typeid(Target).name()))
+    {
+      if (min < limit::min())
+      {
+        EXPECT_THROWS_AS(wire::integer::cast_signed<Target>(std::intmax_t(limit::min()) - 1), wire::exception);
+        EXPECT_THROWS_AS(wire::integer::cast_signed<Target>(min), wire::exception);
+      }
+      EXPECT(limit::min() == wire::integer::cast_signed<Target>(std::intmax_t(limit::min())));
+      EXPECT(Target(0) == wire::integer::cast_signed<Target>(std::intmax_t(0)));
+      EXPECT(limit::max() == wire::integer::cast_signed<Target>(std::intmax_t(limit::max())));
+      if (limit::max() < max)
+      {
+        EXPECT_THROWS_AS(wire::integer::cast_signed<Target>(std::intmax_t(limit::max()) + 1), wire::exception);
+        EXPECT_THROWS_AS(wire::integer::cast_signed<Target>(max), wire::exception);
+      }
+    }
+  }
+}
+
+
+LWS_CASE("wire::integer::cast_*")
+{
+  SETUP("unsigned to unsigned")
+  {
+    test_unsigned_to_unsigned<std::uint8_t>(lest_env);
+    test_unsigned_to_unsigned<std::uint16_t>(lest_env);
+    test_unsigned_to_unsigned<std::uint32_t>(lest_env);
+    test_unsigned_to_unsigned<std::uint64_t>(lest_env);
+    test_unsigned_to_unsigned<std::uintmax_t>(lest_env);
+  }
+  SETUP("signed to signed")
+  {
+    test_signed_to_signed<std::int8_t>(lest_env);
+    test_signed_to_signed<std::int16_t>(lest_env);
+    test_signed_to_signed<std::int32_t>(lest_env);
+    test_signed_to_signed<std::int64_t>(lest_env);
+    test_signed_to_signed<std::intmax_t>(lest_env);
+  }
+}