Add more tests for assigning (to) invalid Strings

Author: matthijskooijman

Diff for: test/src/String/test_operators.cpp

@@ -121,15 +121,23 @@ TEST_CASE ("Testing & String::operator = (const String &) with invalid buffer of
   REQUIRE(str1.compareTo(str2) == 0);
 }
 
-TEST_CASE ("Testing & String::operator = (const char *)", "[String-operator+-14]")
+TEST_CASE ("Testing & String::operator = (const char *) with NULL does not leave string unchanged", "[String-operator+-14]")
 {
   char *buffer = NULL;
   arduino::String str("Hello");
   str = buffer;
   REQUIRE(str.compareTo("Hello") != 0);
 }
 
-TEST_CASE ("Testing & String::operator = (const String &) with invalid buffer of first string", "[String-operator+-15]")
+TEST_CASE ("Testing & String::operator = (const char *) with NULL produces invalid string", "[String-operator+-14]")
+{
+  char *buffer = NULL;
+  arduino::String str("Hello");
+  str = buffer;
+  REQUIRE_FALSE(str);
+}
+
+TEST_CASE ("Testing & String::operator = (const String &) on invalid String updates it", "[String-operator+-15]")
 {
   char *buffer1 = NULL;
   arduino::String str1(buffer1);
@@ -140,6 +148,17 @@ TEST_CASE ("Testing & String::operator = (const String &) with invalid buffer of
   REQUIRE(str1.compareTo(str2) == 0);
 }
 
+TEST_CASE ("Testing & String::operator = (const String &) on invalid String makes it valid", "[String-operator+-15]")
+{
+  char *buffer1 = NULL;
+  arduino::String str1(buffer1);
+
+  arduino::String str2("Hello");
+
+  str1 = str2;
+  REQUIRE(str1);
+}
+
 TEST_CASE ("Testing & String::operator = (String &&)", "[String-operator+-16]")
 {
   arduino::String str("Hello");