test logging

tests/glow/log.cc

+#include <doctest.hh>
+
+#include <sstream>
+
+#include <glow/common/log.hh>
+
+#include <glm/ext.hpp>
+#include <tg/typed-geometry-std.hh>
+
+namespace
+{
+struct Foo1
+{
+};
+std::ostream& operator<<(std::ostream& os, Foo1 const&)
+{
+    return os;
+}
+
+struct Foo2
+{
+};
+std::string to_string(Foo2 const&)
+{
+    return "";
+}
+}
+
+TEST_CASE("glow::log usages")
+{
+    std::stringstream ss;
+    glow::setLogStream(&ss, &ss);
+
+    glow::info() << 0;
+    glow::info() << "hello world";
+    glow::info() << glm::vec3();
+    glow::info() << glm::mat4();
+    glow::info() << tg::pos3();
+    glow::info() << tg::mat4();
+    glow::info() << std::string("hello world");
+    glow::info() << Foo1();
+    glow::info() << Foo2();
+
+    ss << Foo1() << to_string(Foo2()); // to silence warning
+
+    glow::setLogStream(nullptr, nullptr);
+}