xo-unit: utest: + bpu test to verify bpu is structurual type

utest/bpu.test.cpp

@@ -0,0 +1,36 @@
+/* @file bpu.test.cpp */
+
+#include "xo/unit/bpu.hpp"
+//#include "xo/indentlog/scope.hpp"
+#include <catch2/catch.hpp>
+
+namespace xo {
+    namespace qty {
+        using bpu64_type = bpu<std::int64_t>;
+
+        /* compile-time test:
+         * verify we can use a bpu as a non-type template parameter.
+         * Will need this for quantity<Repr, Int, natural_unit<Int>>
+         */
+        template <bpu64_type bpu>
+        constexpr bpu_abbrev_type bpu_mpl_abbrev = bpu.abbrev();
+
+        TEST_CASE("bpu", "[bpu]") {
+            //constexpr bool c_debug_flag = false;
+
+            // can get bits from /dev/random by uncommenting the 2nd line below
+            //uint64_t seed = xxx;
+            //rng::Seed<xoshio256ss> seed;
+
+            //auto rng = xo::rng::xoshiro256ss(seed);
+
+            //scope log(XO_DEBUG2(c_debug_flag, "TEST_CASE.bpu"));
+            //log && log("(A)", xtag("foo", foo));
+
+            static_assert(bpu_mpl_abbrev<bpu64_type::unit_power(bu::gram)> == bpu64_type::unit_power(bu::gram).abbrev());
+            REQUIRE(bpu_mpl_abbrev<bpu64_type::unit_power(bu::gram)> == bpu64_type::unit_power(bu::gram).abbrev());
+        } /*TEST_CASE(bpu)*/
+    } /*namespace qty*/
+} /*namespace xo*/
+
+/* end bpu.test.cpp */