sqrt test

test/test.cpp

@@ -32,3 +32,8 @@ TEST_CASE( "Test modulo function", "[calc]") {
   REQUIRE( evaluate("32%") == 1 );
   REQUIRE( evaluate("51%") == 4 );
 }
+
+
+TEST_CASE("Test sqrt function", "[calc]") {
+  REQUIRE( evaluate("9sqrt") == 3 );
+}