add some basic unit test infra to allow testing together with impl

ostd/range.hh

@@ -37,6 +37,8 @@
 #ifndef OSTD_RANGE_HH
 #define OSTD_RANGE_HH
 
+#include "ostd/unit_test.hh"
+
 #include <cstddef>
 #include <new>
 #include <tuple>
@@ -1328,6 +1330,17 @@ inline auto range(T v) {
     return detail::number_range<T>(v);
 }
 
+OSTD_UNIT_TEST(range, {
+    auto r = range(5, 10, 2);
+    fail_if(r.empty() || (r.front() != 5));
+    r.pop_front();
+    fail_if(r.empty() || (r.front() != 7));
+    r.pop_front();
+    fail_if(r.empty() || (r.front() != 9));
+    r.pop_front();
+    fail_if(!r.empty());
+});
+
 namespace detail {
     template<typename T>
     struct reverse_range: input_range<reverse_range<T>> {

ostd/unit_test.hh

@@ -0,0 +1,113 @@
+/** @defgroup Testing
+ *
+ * @brief Reusable unit test infrastructure.
+ *
+ * This module defines header-only infra for unit tests that can be used to
+ * integrate tests directly where the implementation is. All you really need
+ * to do then is enable a macro, include the file you're testing and compile
+ * into an executable.
+ *
+ * @{
+ */
+
+/** @file unit_test.hh
+ *
+ * @brief The unit test infrastructure implementation.
+ *
+ * Include this at the very beginning in the files you want to define unit
+ * tests in. It has no dependencies within libostd.
+ *
+ * @copyright See COPYING.md in the project tree for further information.
+ */
+
+#ifndef OSTD_UNIT_TEST_HH
+#define OSTD_UNIT_TEST_HH
+
+#ifdef OSTD_BUILD_TESTS
+#include <cstdio>
+#include <cstddef>
+#include <vector>
+#include <string>
+#include <functional>
+#include <stdexcept>
+#endif
+
+namespace ostd {
+namespace test {
+
+/** @addtogroup Testing
+ * @{
+ */
+
+#ifdef OSTD_BUILD_TESTS
+
+#define OSTD_TEST_MODULE_STRINGIFY(x) #x
+#define OSTD_TEST_MODULE_STR(x) OSTD_TEST_MODULE_STRINGIFY(x)
+#define OSTD_TEST_MODULE OSTD_TEST_MODULE_STR(OSTD_BUILD_TESTS)
+
+static std::vector<void (*)()> test_cases;
+
+static bool add_test(std::string testn, void (*func)()) {
+    if (testn == OSTD_TEST_MODULE) {
+        test_cases.push_back(func);
+    }
+    return true;
+}
+
+#define OSTD_UNIT_TEST(module, body) \
+static bool test_case_##module##_##__LINE__ = \
+    ostd::test::add_test(#module, []() { using namespace ostd::test; body });
+
+struct test_error {};
+
+void fail_if(bool b) {
+    if (b) {
+        throw test_error{};
+    }
+}
+
+void fail_if_not(bool b) {
+    if (!b) {
+        throw test_error{};
+    }
+}
+
+void run() {
+    int succ = 0, fail = 0;
+    for (auto &f: test_cases) {
+        try {
+            f();
+        } catch (test_error) {
+            ++fail;
+            continue;
+        }
+        ++succ;
+    }
+#if defined(_WIN32) || defined(WIN32)
+    printf(
+        "%s...\t%d out of %d (%d failures)\n",
+        OSTD_TEST_MODULE, succ, succ + fail, fail
+    );
+#else
+    printf(
+        "%s...\t%s\033[1m%d out of %d\033[0m (%d failures)\n",
+        OSTD_TEST_MODULE, fail ? "\033[91m" : "\033[92m",
+        succ, succ + fail, fail
+    );
+#endif
+}
+
+#else /* OSTD_BUILD_TESTS */
+
+#define OSTD_UNIT_TEST(module, body)
+
+#endif /* OSTD_BUILD_TESTS */
+
+/** @} */
+
+} /* namespace test */
+} /* namespace ostd */
+
+#endif
+
+/** @} */

test_runner.cc

@@ -36,17 +36,12 @@ int main() {
     /* do not change past this point */
 
     int nsuccess = 0, nfailed = 0;
-    std::string modname = nullptr;
+    std::string modname;
 
-    auto print_result = [&](string_range fmsg = nullptr) {
+    auto print_error = [&](string_range fmsg) {
         write(modname, "...\t");
-        if (!fmsg.empty()) {
-            writeln(COLOR_RED, COLOR_BOLD, '(', fmsg, ')', COLOR_END);
-            ++nfailed;
-        } else {
-            writeln(COLOR_GREEN, COLOR_BOLD, "(success)", COLOR_END);
-            ++nsuccess;
-        }
+        writeln(COLOR_RED, COLOR_BOLD, '(', fmsg, ')', COLOR_END);
+        ++nfailed;
     };
 
     filesystem::directory_iterator ds{testdir};
@@ -70,7 +65,7 @@ int main() {
 
         auto cxxcmd = appender<std::string>();
         format(
-            cxxcmd, "%s %s%s%s -o %s %s", compiler, testdir,
+            cxxcmd, "%s %s%s%s -o %s %s ", compiler, testdir,
             char(filesystem::path::preferred_separator),
             p.filename(), exepath, cxxflags
         );
@@ -78,20 +73,24 @@ int main() {
             cxxcmd.get() += ' ';
             cxxcmd.get() += userflags;
         }
+        cxxcmd.get() += ' ';
+        cxxcmd.get() += "-DOSTD_BUILD_TESTS=";
+        cxxcmd.get() += modname;
+
         int ret = system(cxxcmd.get().data());
         if (ret) {
-            print_result("compile errror");
+            print_error("compile errror");
             continue;
         }
 
         ret = system(exepath.data());
         if (ret) {
-            print_result("runtime error");
+            print_error("runtime error");
             continue;
         }
 
         remove(exepath.data());
-        print_result();
+        ++nsuccess;
     }
 
     writeln("\n", COLOR_BLUE, COLOR_BOLD, "testing done:", COLOR_END);

tests/range.cc

@@ -0,0 +1,9 @@
+#define OSTD_BUILD_TESTS range
+
+#include <ostd/unit_test.hh>
+#include <ostd/range.hh>
+
+int main() {
+    ostd::test::run();
+    return 0;
+}