test coverage and some magic constant refactoring

unit_tests/tests/lua/test_can_filter.cpp

@@ -0,0 +1,50 @@
+#include "pch.h"
+#include "can_filter.h"
+
+TEST(CanFilterTest, acceptAny) {
+	CanFilter filterAny;
+
+	filterAny.Id = 0;
+	filterAny.Mask = 0;
+
+	ASSERT_TRUE(filterAny.accept(1));
+	ASSERT_TRUE(filterAny.accept(239));
+}
+
+TEST(CanFilterTest, acceptOnlyExact) {
+	CanFilter filterSpecific;
+
+	filterSpecific.Id = 239;
+	filterSpecific.Mask = FILTER_SPECIFIC;
+
+	ASSERT_FALSE(filterSpecific.accept(1));
+	ASSERT_TRUE(filterSpecific.accept(239));
+}
+
+#define CALLBACK_ALL 3
+#define CALLBACK_239 5
+
+TEST(CanFilterTest, orderOfBusinessOne) {
+	resetLuaCanRx();
+
+	// accept everything as first filter
+	addLuaCanRxFilter(/*eid*/0, 0, ANY_BUS, CALLBACK_ALL);
+
+	addLuaCanRxFilter(/*eid*/239, FILTER_SPECIFIC, ANY_BUS, CALLBACK_239);
+
+	// filters are applied in the order in which those were added
+	ASSERT_EQ(CALLBACK_ALL, getFilterForId(/*bus*/0, /*id*/ 0)->Callback);
+	ASSERT_EQ(CALLBACK_ALL, getFilterForId(/*bus*/0, /*id*/ 239)->Callback);
+}
+
+TEST(CanFilterTest, orderOfBusinessTwo) {
+	resetLuaCanRx();
+
+	addLuaCanRxFilter(/*eid*/239, FILTER_SPECIFIC, ANY_BUS, CALLBACK_239);
+	// accept everything as last filter
+	addLuaCanRxFilter(/*eid*/0, 0, ANY_BUS, CALLBACK_ALL);
+
+	// filters are applied in the order in which those were added
+	ASSERT_EQ(CALLBACK_ALL, getFilterForId(/*bus*/0, /*id*/ 0)->Callback);
+	ASSERT_EQ(CALLBACK_239, getFilterForId(/*bus*/0, /*id*/ 239)->Callback);
+}