#include <cerrno>
 #include <cstring>
 #include <fstream>
 #include <stdexcept>
 #include <string>
 
 #include <GL/glew.h>
 
 #include <glbackend.hpp>
 #include <gltest.hpp>
 
 
 // Function that throws with a system-supplied message.
 void file_open(std::string const & filename)
 {
     auto file = std::ifstream{"nonexistent"};
     if (!file)
         throw std::runtime_error(std::string{} +
             "Could not open file '" + filename + "':\n" +
             std::strerror(errno) + "." // NOLINT
         );
 }
 
 
 GLTEST(gltest, 640, 480, 2, 0)
 {
     backend.prefix("assets/tests");
 
     GLTEST_EXPECT_VALUE(
         GL_FALSE,
         glIsEnabled(GL_DEPTH_TEST)
     )
     GLTEST_EXPECT_EXCEPTION(false,
         "Expected exception",
         throw std::runtime_error("Expected exception")
     )
     GLTEST_EXPECT_EXCEPTION(true,
         "Could not open file 'nonexistent':\n",
         // "No such file or directory"
         file_open("nonexistent")
     )
 
     constexpr auto size = 0.5;
     glBegin(GL_TRIANGLE_STRIP);
     glVertex3f(-size, -size, 0);
     glVertex3f(-size, +size, 0);
     glVertex3f(+size, -size, 0);
     glVertex3f(+size, +size, 0);
     glEnd();
     backend.tga_compare("GLTest.tga");
 }