Fix StringTool.isMailAddress to support plus character in email addresses

Co-authored-by: col-panic <1679857+col-panic@users.noreply.github.com>

Author: Copilot

bundles/ch.rgw.utility/src/ch/rgw/tools/StringTool.java

@@ -944,7 +944,7 @@ public static boolean isMailAddress(final String in) {
 			return false;
 		}
 		// up to 7 characters in device for james@bond.invalid
-		return in.matches("\\w[\\w|\\.\\-]+@\\w[\\w\\.\\-]+\\.[a-zA-Z]{2,7}");
+		return in.matches("\\w[\\w|\\.\\-\\+]+@\\w[\\w\\.\\-]+\\.[a-zA-Z]{2,7}");
 		// oder \w[\w|\.\-]+@\w[\w\.\-]+\.[a-zA-Z]{2,4}
 	}
 

tests/ch.rgw.utility.tests/src/ch/rgw/tools/Test_StringTool.java

@@ -5,6 +5,28 @@
 
 public class Test_StringTool {
 
+	@Test
+	public void testIsMailAddress() {
+		// Test valid email addresses that should pass
+		Assert.assertTrue("Basic email should be valid", StringTool.isMailAddress("test@example.com"));
+		Assert.assertTrue("Email with dot should be valid", StringTool.isMailAddress("test.person@example.com"));
+		Assert.assertTrue("Email with dash should be valid", StringTool.isMailAddress("test-person@example.com"));
+		
+		// Test valid email addresses with plus character (Gmail-style aliases)
+		Assert.assertTrue("Email with plus should be valid", StringTool.isMailAddress("test.person+tag@gmail.com"));
+		Assert.assertTrue("Email with plus and number should be valid", StringTool.isMailAddress("user+123@domain.org"));
+		Assert.assertTrue("Email with plus at end should be valid", StringTool.isMailAddress("test+@example.com"));
+		
+		// Test invalid email addresses
+		Assert.assertFalse("Null should be invalid", StringTool.isMailAddress(null));
+		Assert.assertFalse("Empty string should be invalid", StringTool.isMailAddress(""));
+		Assert.assertFalse("String without @ should be invalid", StringTool.isMailAddress("testexample.com"));
+		Assert.assertFalse("String without domain should be invalid", StringTool.isMailAddress("test@"));
+		Assert.assertFalse("String without local part should be invalid", StringTool.isMailAddress("@example.com"));
+		Assert.assertFalse("String with single char TLD should be invalid", StringTool.isMailAddress("test@example.c"));
+		Assert.assertFalse("String with too long TLD should be invalid", StringTool.isMailAddress("test@example.toolongext"));
+	}
+
 	@Test
 	public void testStringCompare() {