Make initialization fail with a specific exception if the dataset isn't compatible with the algorithm being used, rather than crashing when a query occurs.

unit_tests/library/algorithm.cpp

@@ -0,0 +1,34 @@
+#include <boost/test/test_case_template.hpp>
+#include <boost/test/unit_test.hpp>
+
+#include "fixture.hpp"
+
+#include "osrm/exception.hpp"
+
+BOOST_AUTO_TEST_SUITE(table)
+
+BOOST_AUTO_TEST_CASE(test_incompatible_with_mld)
+{
+    // Can't use the MLD algorithm with CH data
+    BOOST_CHECK_THROW(
+        getOSRM(OSRM_TEST_DATA_DIR "/ch/monaco.osrm", osrm::EngineConfig::Algorithm::MLD),
+        osrm::exception);
+}
+
+BOOST_AUTO_TEST_CASE(test_incompatible_with_corech)
+{
+    // Note - CH-only data can't be used with the CoreCH algorithm
+    BOOST_CHECK_THROW(
+        getOSRM(OSRM_TEST_DATA_DIR "/ch/monaco.osrm", osrm::EngineConfig::Algorithm::CoreCH),
+        osrm::exception);
+}
+
+BOOST_AUTO_TEST_CASE(test_incompatible_with_ch)
+{
+    // Can't use the CH algorithm with MLD data
+    BOOST_CHECK_THROW(
+        getOSRM(OSRM_TEST_DATA_DIR "/mld/monaco.osrm", osrm::EngineConfig::Algorithm::CH),
+        osrm::exception);
+}
+
+BOOST_AUTO_TEST_SUITE_END()

unit_tests/library/fixture.hpp

@@ -9,11 +9,14 @@
 // I couldn't get Boost.UnitTest to provide a test suite level fixture with custom
 // arguments per test suite (osrm base path from argv), so this has to suffice.
 
-inline osrm::OSRM getOSRM(const std::string &base_path)
+inline osrm::OSRM
+getOSRM(const std::string &base_path,
+        osrm::EngineConfig::Algorithm algorithm = osrm::EngineConfig::Algorithm::CH)
 {
     osrm::EngineConfig config;
     config.storage_config = {base_path};
     config.use_shared_memory = false;
+    config.algorithm = algorithm;
 
     return osrm::OSRM{config};
 }

unit_tests/library/route.cpp

@@ -7,6 +7,7 @@
 
 #include "osrm/coordinate.hpp"
 #include "osrm/engine_config.hpp"
+#include "osrm/exception.hpp"
 #include "osrm/json_container.hpp"
 #include "osrm/json_container.hpp"
 #include "osrm/osrm.hpp"