Finished CRUD API development for the dictionary

Maps/dictionary.go

@@ -1,8 +1,9 @@
 package dictionary
 
 const (
-	ErrNotFound   = DictionaryErr("could not find the word you were looking for")
-	ErrWordExists = DictionaryErr("cannot add word because it already exists")
+	ErrNotFound         = DictionaryErr("could not find the word you were looking for")
+	ErrWordExists       = DictionaryErr("cannot add word because it already exists")
+	ErrWordDoesNotExist = DictionaryErr("cannot update word because it does not exist")
 )
 
 type DictionaryErr string
@@ -37,6 +38,25 @@ func (d Dictionary) Add(word, definition string) error {
 	return nil
 }
 
+func (d Dictionary) Update(word, definition string) error {
+	_, err := d.Search(word)
+
+	switch err {
+	case ErrNotFound:
+		return ErrWordDoesNotExist
+	case nil:
+		d[word] = definition
+	default:
+		return err
+	}
+
+	return nil
+}
+
+func (d Dictionary) Delete(word string) {
+	delete(d, word)
+}
+
 //a map value is a pointer to a hmap structure meaning that when you pass in a map to a function/method you are only copying the pointer address part, which means that you can modify its underlying data!
 
 //you can't create a nil map and then write into it without causing a run time error: looks like this -> var m map[string]string

Maps/dictionary_test.go

@@ -69,3 +69,39 @@ func assertDefinition(t testing.TB, dictionary Dictionary, word, definition stri
 	}
 	assertStrings(t, got, definition)
 }
+
+func TestUpdate(t *testing.T) {
+	t.Run("existing word", func(t *testing.T) {
+		word := "test"
+		definition := "this is just a test"
+		dictionary := Dictionary{word: definition}
+		newDefinition := "new definition"
+
+		err := dictionary.Update(word, newDefinition)
+
+		assertError(t, err, nil)
+		assertDefinition(t, dictionary, word, newDefinition)
+	})
+
+	t.Run("new word", func(t *testing.T) {
+		word := "test"
+		definition := "this is just a test"
+		dictionary := Dictionary{}
+
+		err := dictionary.Update(word, definition)
+
+		assertError(t, err, ErrWordDoesNotExist)
+	})
+}
+
+func TestDelete(t *testing.T) {
+	word := "test"
+	dictionary := Dictionary{word: "test definition"}
+
+	dictionary.Delete(word)
+
+	_, err := dictionary.Search(word)
+	if err != ErrNotFound {
+		t.Errorf("Expected %q to be deleted", word)
+	}
+}