Improve handling of AssertionError

- Assert can now take one or two arguments: first argument is the assertion
  itself. The optional second argument is used to provide a custom error
  message.

- remove try/catch from main: AssertionError may now be catched in
  SignalManager. This allows to write the AssertionError message as well as to
  print the back trace and eventually pause the execution.

src/main.cpp

@@ -28,10 +28,8 @@
 int main(int argc, char *argv[])
 {
   std::string filename = initialize(argc, argv);
-
   std::map<std::string, double> method_cost_map;
 
-  try  {
   if (filename != "") {
     pout() << "Reading (gmsh) " << rang::style::underline << filename << rang::style::reset << " ...\n";
     Timer gmsh_timer;
@@ -374,11 +372,6 @@ int main(int argc, char *argv[])
     perr() << "Connectivity1D defined by number of nodes no more implemented\n";
     std::exit(0);
   }
-  }
-  catch (const AssertError& error) {
-    perr() << error << '\n';
-    std::exit(1);
-  }
 
   finalize();
 

src/utils/PastisAssert.hpp

@@ -7,12 +7,19 @@
 #include <iostream>
 #include <string>
 
+template <typename ErrorType>
+void printAndThrow(const ErrorType& error)
+{
+  throw error;
+}
+
 class AssertError
 {
  private:
   const std::string m_file;
   const int m_line;
   const std::string m_function;
+  const std::string m_test;
   const std::string m_message;
 
  public:
@@ -22,11 +29,16 @@ class AssertError
   {
     os << '\n'
        << rang::style::bold
-       << "*** Assertion error ***\n"
+       << "---------- Assertion error -----------\n"
        << " at " << assert_error.m_file << ':' << assert_error.m_line << '\n'
        << " in " << assert_error.m_function << '\n'
-       << "*** " << rang::fgB::red << assert_error.m_message << rang::fg::reset
-       << rang::style::reset << '\n';
+       << " assertion (" << rang::fgB::red << assert_error.m_test << rang::fg::reset
+       << ") failed!\n";
+    if (not assert_error.m_message.empty()) {
+      os << ' ' << rang::fgB::yellow << assert_error.m_message
+         << rang::fg::reset << '\n';
+    }
+    os << "--------------------------------------" << rang::style::reset << '\n';
 
     return os;
   }
@@ -35,10 +47,12 @@ class AssertError
   AssertError(std::string file,
               int line,
               std::string function,
-              std::string message)
+              std::string test,
+              std::string message="")
       : m_file(file),
         m_line(line),
         m_function(function),
+        m_test(test),
         m_message(message)
   {
     ;
@@ -59,17 +73,32 @@ PRAGMA_DIAGNOSTIC_POP
 #ifdef NDEBUG
 
 // Useless test is there to check syntax even in optimized mode. Costs nothing.
-#define Assert(assertion)                       \
-  if (not _pastis_assert(assertion)) {}
+#define Assert(assertion,...)                                   \
+  if (not _pastis_assert(assertion)) {                          \
+    using vargs_t = decltype(std::make_tuple(__VA_ARGS__));     \
+    static_assert(std::tuple_size_v<vargs_t> <= 1,              \
+                  "too many arguments");                        \
+  }
 
 #else // NDEBUG
 
-#define Assert(assertion)                       \
+#define Assert(assertion,...)                                   \
   if (not _pastis_assert(assertion)) {                          \
-    throw AssertError(__FILE__,                 \
+    using vargs_t = decltype(std::make_tuple(__VA_ARGS__));     \
+    static_assert(std::tuple_size_v<vargs_t> <= 1,              \
+                  "too many arguments");                        \
+    if constexpr(std::tuple_size_v<vargs_t> == 0) {             \
+        printAndThrow(AssertError(__FILE__,                     \
+                                  __LINE__,                     \
+                                  __PRETTY_FUNCTION__,          \
+                                  #assertion));                 \
+      } else {                                                  \
+      printAndThrow(AssertError(__FILE__,                       \
                                 __LINE__,                       \
                                 __PRETTY_FUNCTION__,            \
-                      (#assertion));            \
+                                #assertion,                     \
+                                #__VA_ARGS__));                 \
+    }                                                           \
   }
 
 #endif // NDEBUG

src/utils/SignalManager.cpp

 #include <SignalManager.hpp>
 
+#include <PastisAssert.hpp>
 #include <PastisOStream.hpp>
 
 #include <BacktraceManager.hpp>
@@ -60,6 +61,19 @@ void SignalManager::handler(int signal)
   std::signal(SIGINT,  SIG_DFL);
   std::signal(SIGABRT, SIG_DFL);
 
+  std::exception_ptr eptr = std::current_exception();
+  try {
+    if (eptr) {
+      std::rethrow_exception(eptr);
+    }
+  }
+  catch(const AssertError& assert_error) {
+    perr() << assert_error << '\n';
+  }
+  catch(...) {
+    perr() << "Unknown exception!\n";
+  }
+
   perr() << "\n *** "
 	    << rang::style::reset
 	    << rang::fg::reset

tests/test_PastisAssert.cpp

@@ -8,10 +8,22 @@ TEST_CASE("PastisAssert", "[utils]") {
     const std::string filename = "filename";
     const int line = 10;
     const std::string function = "function";
+    const std::string test = "test";
+
+    AssertError assert_error(filename, line, function, test);
+
+    REQUIRE(Catch::Detail::stringify(assert_error) == "\n---------- Assertion error -----------\n at filename:10\n in function\n assertion (test) failed!\n--------------------------------------\n");
+  }
+
+  SECTION("checking for assert error with message") {
+    const std::string filename = "filename";
+    const int line = 10;
+    const std::string function = "function";
+    const std::string test = "test";
     const std::string message = "message";
 
-    AssertError assert_error(filename, line, function, message);
+    AssertError assert_error(filename, line, function, test, message);
 
-    REQUIRE(Catch::Detail::stringify(assert_error) == "\n*** Assertion error ***\n at filename:10\n in function\n*** message\n");
+    REQUIRE(Catch::Detail::stringify(assert_error) == "\n---------- Assertion error -----------\n at filename:10\n in function\n assertion (test) failed!\n message\n--------------------------------------\n");
   }
 }