Update Help window and add tests

src/main/java/seedu/address/ui/HelpWindow.java

@@ -33,9 +33,9 @@ public class HelpWindow extends UiPart<Stage> {
             + "4. Edit a Person\n"
             + "   Edits an existing contact by index.\n"
             + "   Format: edit INDEX [n/NAME] [p/PHONE] [e/EMAIL] [t/TELEGRAM] [r/ROLE]\n\n"
-            + "5. Find by Name or Role\n"
-            + "   Finds contacts whose names or roles contain the specified keywords.\n"
-            + "   Format: find [n/NAME] [r/ROLE]\n\n"
+            + "5. Find by Name or Role or Telegram\n"
+            + "   Finds contacts whose names or roles or telegram handles contain the specified keywords.\n"
+            + "   Format: find [n/NAME] [r/ROLE] [t/TELEGRAM]\n\n"
             + "6. View contact by telegram handle\n"
             + "   View detailed information of a contact with the specified telegram handle\n"
             + "   Format: view t/TELEGRAM\n\n"

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

@@ -55,6 +55,7 @@ public void equals() {
                 secondRolePredicate, secondTelegramPredicate);
         FindCommand findFourthCommand = new FindCommand(secondNamePredicate,
                 firstRolePredicate, firstTelegramPredicate);
+        FindCommand findFifthCommand = new FindCommand(firstNamePredicate, firstRolePredicate, secondTelegramPredicate);
 
         // same object -> returns true
         assertTrue(findFirstCommand.equals(findFirstCommand));
@@ -78,6 +79,9 @@ public void equals() {
 
         // different role predicate only -> returns false
         assertFalse(findFirstCommand.equals(findThirdCommand));
+
+        // different telegram predicate only -> returns false
+        assertFalse(findFirstCommand.equals(findFifthCommand));
     }
 
     @Test

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

@@ -0,0 +1,85 @@
+package seedu.address.model.person;
+
+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 java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+
+import seedu.address.testutil.PersonBuilder;
+
+public class TelegramContainsKeywordsPredicateTest {
+
+    @Test
+    public void equals() {
+        List<String> firstPredicateKeywordList = Collections.singletonList("first");
+        List<String> secondPredicateKeywordList = Arrays.asList("first", "second");
+
+        TelegramContainsKeywordsPredicate firstPredicate = new TelegramContainsKeywordsPredicate(
+                firstPredicateKeywordList);
+        TelegramContainsKeywordsPredicate secondPredicate = new TelegramContainsKeywordsPredicate(
+                secondPredicateKeywordList);
+
+        // same object -> returns true
+        assertTrue(firstPredicate.equals(firstPredicate));
+
+        // same values -> returns true
+        TelegramContainsKeywordsPredicate firstPredicateCopy = new TelegramContainsKeywordsPredicate(
+                firstPredicateKeywordList);
+        assertTrue(firstPredicate.equals(firstPredicateCopy));
+
+        // different types -> returns false
+        assertFalse(firstPredicate.equals(1));
+
+        // null -> returns false
+        assertFalse(firstPredicate.equals(null));
+
+        // different person -> returns false
+        assertFalse(firstPredicate.equals(secondPredicate));
+    }
+
+    @Test
+    public void test_telegramContainsKeywords_returnsTrue() {
+        // One keyword
+        TelegramContainsKeywordsPredicate predicate = new TelegramContainsKeywordsPredicate(Collections
+                .singletonList("javierTan"));
+        assertTrue(predicate.test(new PersonBuilder().withTelegram("javierTan").build()));
+
+        // Multiple keywords
+        predicate = new TelegramContainsKeywordsPredicate(Arrays.asList("javiertan", "melinda"));
+        assertTrue(predicate.test(new PersonBuilder().withTelegram("melinda").build()));
+
+        // Mixed-case keywords
+        predicate = new TelegramContainsKeywordsPredicate(Arrays.asList("AbCd", "QqQQ"));
+        assertTrue(predicate.test(new PersonBuilder().withTelegram("abcd").build()));
+    }
+
+    @Test
+    public void test_nameDoesNotContainKeywords_returnsFalse() {
+        // Zero keywords
+        TelegramContainsKeywordsPredicate predicate = new TelegramContainsKeywordsPredicate(Collections.emptyList());
+        assertFalse(predicate.test(new PersonBuilder().withTelegram("alisa").build()));
+
+        // Non-matching keyword
+        predicate = new TelegramContainsKeywordsPredicate(Arrays.asList("ben"));
+        assertFalse(predicate.test(new PersonBuilder().withTelegram("boy").build()));
+
+        // Keywords match name, phone and role, but does not match telegram
+        predicate = new TelegramContainsKeywordsPredicate(Arrays.asList("Alice", "12345678", "alice", "member"));
+        assertFalse(predicate.test(new PersonBuilder().withName("Alice").withPhone("12345678")
+                .withTelegram("alicePauline").withRoles("member").build()));
+    }
+
+    @Test
+    public void toStringMethod() {
+        List<String> keywords = List.of("keyword1", "keyword2");
+        TelegramContainsKeywordsPredicate predicate = new TelegramContainsKeywordsPredicate(keywords);
+
+        String expected = TelegramContainsKeywordsPredicate.class.getCanonicalName() + "{keywords=" + keywords + "}";
+        assertEquals(expected, predicate.toString());
+    }
+}