public static void Remove_uses_linear_probing_on_collisions_Test()
{
HashMap <StringKey, Item> hashMap = new HashMap <StringKey, Item>();
Entry <StringKey, Item>[] table = hashMap.Table;
Item item1Value = new Item("Purse", 10, 1);
StringKey item1Key = new StringKey(item1Value.Name);
Item item2Value = new Item("Helmet", 3, 2.5);
StringKey item2Key = new StringKey(item2Value.Name);
hashMap.Put(item1Key, item1Value);
int bucket1 = item1Key.GetHashCode() % table.Length;
int bucket2 = item2Key.GetHashCode() % table.Length;
// check to see if there is a collision
Assert.AreEqual(bucket1, bucket2);
// causes a collision, test for linear probing here!
hashMap.Put(item2Key, item2Value);
// The second item is in the next available index
Assert.AreEqual(item2Value, table[((bucket1 + 1) % table.Length)].Value);
//Test Remove HERE
}
public static void Put_Overwrites_Value_At_Key_On_Update_Test()
{
HashMap <StringKey, Item> hashMap = new HashMap <StringKey, Item>();
StringKey key = new StringKey("item");
Item originalItem = new Item("item", 1, 1.0);
Item newItem = new Item("item", 2, 2.0);
hashMap.Put(key, originalItem);
Item oldValue = hashMap.Put(key, newItem);
Entry <StringKey, Item>[] table = hashMap.Table;
int bucket = key.GetHashCode() % table.Length;
Assert.AreEqual(newItem, table[bucket].Value);
// doing a thourough check that the OLD value is no longer in the map anywhere
bool isFound = false;
for (int i = 0; i < table.Length; i++)
{
if (table[i] != null && table[i].Value.Equals(oldValue) && table[i].Key.Equals(key))
{
isFound = true;
}
}
Assert.IsFalse(isFound);
}
public static void GetHashCodeEmptyNameTest()
{
int expectedResult = 0;
StringKey stringKey = new StringKey("");
Assert.AreEqual(expectedResult, stringKey.GetHashCode());
}
public static void GetHashCodeVarietyTest()
{
StringKey stringKey1 = new StringKey("stop");
StringKey stringKey2 = new StringKey("pots");
Assert.AreNotEqual(stringKey1.GetHashCode(), stringKey2.GetHashCode());
}
public static void GetHashCodeTest()
{
int expectedResult = 3446974;
StringKey stringKey = new StringKey("stop");
// NOTE: this may differ from your tests, you may ignore this test!
Assert.AreEqual(expectedResult, stringKey.GetHashCode());
}
public void GetHashCodeTest()
{
double coe = 31;
StringKey stringKey = new StringKey("and");
int expected = (int)(('a' - '0') * 1 + ('n' - '0') * coe + ('d' - '0') * coe * coe);
Assert.AreEqual(expected, stringKey.GetHashCode());
}
public static void Put_Adds_Value_To_Hash_Test()
{
HashMap <StringKey, Item> hashMap = new HashMap <StringKey, Item>();
StringKey key = new StringKey("item");
Item item = new Item("item", 1, 1.0);
hashMap.Put(key, item);
Entry <StringKey, Item>[] table = hashMap.Table;
int bucket = key.GetHashCode() % table.Length;
Assert.AreEqual(item, table[bucket].Value);
}
public override int GetHashCode()
{
int hash = 1;
if (typeCase_ == TypeOneofCase.StringKey)
{
hash ^= StringKey.GetHashCode();
}
hash ^= (int)typeCase_;
if (_unknownFields != null)
{
hash ^= _unknownFields.GetHashCode();
}
return(hash);
}
public static void Remove_keeps_a_key_placeholder_Test()
{
HashMap <StringKey, Item> hashMap = new HashMap <StringKey, Item>();
StringKey key = new StringKey("item");
Item item = new Item("item", 1, 1.0);
hashMap.Put(key, item);
Item returnedItem = hashMap.Remove(key);
Entry <StringKey, Item>[] table = hashMap.Table;
int bucket = key.GetHashCode() % table.Length;
// a placeholder will have an Entry with a null for the value, but the key is stil the same as the removed
Assert.AreEqual(table[bucket].Key, key);
Assert.AreEqual(table[bucket].Value, null);
}
public static void GetHashCode_is_not_negative_Test()
{
StringKey stringKey1 = new StringKey("A REALLY BIG STRING SHOULD NOT OVERFLOW TO NEGATIVE! ALWAYS ABSOLUTE VALUE YOUR HASHCODE!");
Assert.GreaterOrEqual(stringKey1.GetHashCode(), 0);
}