Make sure that proper operator function is used for char[N] argument

apps/openmw_test_suite/esm/test_fixed_string.cpp

@@ -37,6 +37,42 @@ TEST(EsmFixedString, operator__eq_ne)
         EXPECT_TRUE(name == ss);
     }
 }
+TEST(EsmFixedString, operator__eq_ne_const)
+{
+    {
+        SCOPED_TRACE("asdc == asdc (const)");
+        ESM::NAME name;
+        name.assign("asdc");
+        const char s[4] = { 'a', 's', 'd', 'c' };
+        std::string ss(s, 4);
+
+        EXPECT_TRUE(name == s);
+        EXPECT_TRUE(name == ss.c_str());
+        EXPECT_TRUE(name == ss);
+    }
+    {
+        SCOPED_TRACE("asdc == asdcx (const)");
+        ESM::NAME name;
+        name.assign("asdc");
+        const char s[5] = { 'a', 's', 'd', 'c', 'x' };
+        std::string ss(s, 5);
+
+        EXPECT_TRUE(name != s);
+        EXPECT_TRUE(name != ss.c_str());
+        EXPECT_TRUE(name != ss);
+    }
+    {
+        SCOPED_TRACE("asdc == asdc[NULL] (const)");
+        ESM::NAME name;
+        name.assign("asdc");
+        const char s[5] = { 'a', 's', 'd', 'c', '\0' };
+        std::string ss(s, 5);
+
+        EXPECT_TRUE(name == s);
+        EXPECT_TRUE(name == ss.c_str());
+        EXPECT_TRUE(name == ss);
+    }
+}
 
 TEST(EsmFixedString, empty_strings)
 {

components/esm/esmcommon.hpp

@@ -35,7 +35,10 @@ public:
             return false;
         return std::strncmp(self()->ro_data(), str, size) == 0;
     }
-    bool operator==(const char* const str) const
+
+    //this operator will not be used for char[N], only for char*
+    template<typename T, typename = typename std::enable_if<std::is_same<T, char>::value>::type>
+    bool operator==(const T* const& str) const
     {
         char const* const data = self()->ro_data();
         for(size_t i = 0; i < size; ++i)