Update test cases for Task class

src/test/java/gopher/task/TaskTest.java

@@ -1,6 +1,7 @@
 package gopher.task;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import org.junit.jupiter.api.Test;
 
@@ -111,4 +112,77 @@ public void toStringTest() {
         assertEquals("[E][ ] Event 3 (from Aug 30 2024 00:00 to Sep 02 2024 00:00)",
                 event.toString());
     }
+
+    @Test
+    public void update_validCommand_updateSuccess()
+            throws InvalidTokenException, InvalidDurationException {
+        Task todo = createTask("todo Event 1");
+        todo.update(new String[]{"update", "1", "Hello"});
+        assertEquals("[T][ ] Hello",
+                todo.toString());
+
+        Task deadline = createTask("deadline Event 2 /by 2024-08-30");
+        deadline.update(new String[]{"update", "2", "Goodbye World", "/by", "2025-01-01"});
+        assertEquals("[D][ ] Goodbye World (by Jan 01 2025 00:00)",
+                deadline.toString());
+
+        Task event = createTask("event Event 3 /from 2024-08-30 /to 2024-09-02");
+        event.update(new String[]{"update", "3", "Orbital Splashdown", "/from", "2024-01-01",
+                                  "/to", "2025-01-01"});
+        assertEquals("[E][ ] Orbital Splashdown (from Jan 01 2024 00:00 to Jan 01 2025 00:00)",
+                event.toString());
+    }
+
+    @Test
+    public void of_unknownCommand_exceptionThrown() {
+        assertThrows(UnknownCommandException.class, () -> {
+            Task.of("hello");
+        });
+    }
+
+    @Test
+    public void of_emptyDescription_exceptionThrown() {
+        assertThrows(EmptyTaskDescriptionException.class, () -> {
+            Task.of("todo");
+        });
+    }
+
+    @Test
+    public void of_missingByTokenWhenCreatingDeadline_exceptionThrown() {
+        assertThrows(MissingTokenException.class, () -> {
+            Task.of("deadline Goodbye World 2024-09-11");
+        });
+    }
+
+    @Test
+    public void of_invalidDurationForEventTask_exceptionThrown() {
+        assertThrows(InvalidDurationException.class, () -> {
+            Task.of("event hello /from 2024-01-01 /to 2023-01-01");
+        });
+    }
+
+    @Test
+    public void of_fromTokenUsedToCreateDeadline_exceptionThrown() {
+        assertThrows(InvalidTokenException.class, () -> {
+            Task.of("deadline hello /from 2024-01-01");
+        });
+    }
+
+    @Test
+    public void update_byTokenUsedToUpdateEvent_exceptionThrown() {
+        Task event = createTask("event hello /from 2020-01-01 /to 2021-01-01");
+        assertThrows(InvalidTokenException.class, () -> {
+            String[] tokens = new String[]{"update", "4", "/by", "2024-09-11"};
+            event.update(tokens);
+        });
+    }
+
+    @Test
+    public void update_invalidDuration_exceptionThrown() {
+        Task event = createTask("event hello /from 2020-01-01 /to 2021-01-01");
+        assertThrows(InvalidDurationException.class, () -> {
+            String[] tokens = new String[]{"update", "4", "/from", "2024-01-01"};
+            event.update(tokens);
+        });
+    }
 }