Add NricTest and additional test cases in NricMatchesPredicateTest an…

…d ViewCommandTest

src/test/java/seedu/address/logic/commands/ViewCommandTest.java

@@ -1,5 +1,6 @@
 package seedu.address.logic.commands;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static seedu.address.logic.Messages.MESSAGE_NO_PERSON_FOUND;
@@ -71,4 +72,14 @@ public void execute_invalidNric_noPersonFound() {
         assertCommandFailure(viewCommand, model, MESSAGE_NO_PERSON_FOUND);
     }
 
+    @Test
+    public void toStringMethod() {
+        NricMatchesPredicate predicate = new NricMatchesPredicate("S1234567A");
+        ViewCommand viewCommand = new ViewCommand("S1234567A");
+
+        String expectedString = ViewCommand.class.getCanonicalName() + "{predicate=" + predicate + "}";
+
+        assertEquals(expectedString, viewCommand.toString());
+    }
+
 }

src/test/java/seedu/address/model/person/NricMatchesPredicateTest.java

@@ -43,7 +43,7 @@ public void test_nricMatches_returnsTrue() {
     }
 
     @Test
-    public void test_nricMatches_caseInsensitive_returnsTrue() {
+    public void test_caseInsensitive_returnsTrue() {
         NricMatchesPredicate predicate = new NricMatchesPredicate("s1234567a");
         Person person = new PersonBuilder().withNric("S1234567A").build();
 

src/test/java/seedu/address/model/person/NricTest.java

@@ -0,0 +1,70 @@
+package seedu.address.model.person;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static seedu.address.testutil.Assert.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+public class NricTest {
+
+    @Test
+    public void constructor_null_throwsNullPointerException() {
+        assertThrows(NullPointerException.class, () -> new Nric(null));
+    }
+
+    @Test
+    public void constructor_invalidNric_throwsIllegalArgumentException() {
+        String invalidNric = "A123"; // Clearly invalid NRIC format
+        assertThrows(IllegalArgumentException.class, () -> new Nric(invalidNric));
+    }
+
+    @Test
+    public void isValidNric() {
+        // null NRIC
+        assertThrows(NullPointerException.class, () -> Nric.isValidNric(null));
+
+        // invalid NRICs
+        assertFalse(Nric.isValidNric("")); // empty string
+        assertFalse(Nric.isValidNric(" ")); // spaces only
+        assertFalse(Nric.isValidNric("S12345678")); // 8 numbers
+        assertFalse(Nric.isValidNric("S123456E")); // only 7 characters total
+        assertFalse(Nric.isValidNric("S12345E7A")); // non-digit in the middle
+        assertFalse(Nric.isValidNric("1234567A")); // no alphabet at the start
+        assertFalse(Nric.isValidNric("S1234567")); // no alphabet at the end
+        assertFalse(Nric.isValidNric("S1234567*")); // invalid character at the end
+
+        // valid NRICs
+        assertTrue(Nric.isValidNric("S1234567A"));
+        assertTrue(Nric.isValidNric("T7654321Z"));
+        assertTrue(Nric.isValidNric("F0987654B")); // mixed with different first alphabets
+        assertTrue(Nric.isValidNric("G2345678K")); // different ending alphabet
+        assertTrue(Nric.isValidNric("s1234567a")); // lowercase letters at start and end
+    }
+
+    @Test
+    public void equals() {
+        Nric nric = new Nric("S1234567A");
+
+        // same values -> returns true
+        assertTrue(nric.equals(new Nric("S1234567A")));
+
+        // same object -> returns true
+        assertTrue(nric.equals(nric));
+
+        // null -> returns false
+        assertFalse(nric.equals(null));
+
+        // different types -> returns false
+        assertFalse(nric.equals(5.0f));
+
+        // different values -> returns false
+        assertFalse(nric.equals(new Nric("T7654321Z")));
+    }
+
+    @Test
+    public void toStringMethod() {
+        Nric nric = new Nric("S1234567A");
+        assertTrue(nric.toString().equals("S1234567A"));
+    }
+}