HasValidationPropertiesElement

Mixin interface for components exposing validation state and error messages

Overview

HasValidationPropertiesElement provides methods for interacting with Vaadin components that support validation states and error messages. It allows you to check whether a component is valid or invalid, and to assert the presence and content of error messages.

Interface Location: org.vaadin.addons.dramafinder.element.shared.HasValidationPropertiesElement

Methods

getErrorMessageLocator()

default Locator getErrorMessageLocator()

Returns a locator for the error message slot element.

Returns: Locator - Locator for the element with slot="error-message"

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assertValid()

default void assertValid()

Asserts that the component is valid (does not have the invalid attribute).

Throws: AssertionError if the component has the invalid attribute

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assertInvalid()

default void assertInvalid()

Asserts that the component is invalid (has the invalid attribute).

Throws: AssertionError if the component does not have the invalid attribute

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assertErrorMessage()

default void assertErrorMessage(String errorMessage)

Asserts that the error message equals the expected text.

errorMessage · String · required

The expected error message text

Throws: AssertionError if the error message does not match

Implementing Classes

The following element classes implement HasValidationPropertiesElement:

• TextFieldElement (and its subclasses)
• AbstractNumberFieldElement (and its subclasses)
• DatePickerElement
• DateTimePickerElement
• TimePickerElement
• RadioButtonGroupElement

Usage Example

import org.vaadin.addons.dramafinder.element.TextFieldElement;
import com.microsoft.playwright.Page;

public class ValidationTest {
    void testValidation(Page page) {
        TextFieldElement emailField = TextFieldElement.getByLabel(page, "Email");
        
        // Initially valid
        emailField.assertValid();
        
        // Enter invalid email
        emailField.setValue("invalid-email");
        emailField.blur();
        
        // Check validation state
        emailField.assertInvalid();
        emailField.assertErrorMessage("Please enter a valid email address");
        
        // Fix the error
        emailField.setValue("[e-mail]");
        emailField.blur();
        emailField.assertValid();
    }
}

Implementation Details

Error Message Slot

Vaadin components use a slot-based architecture for error messages. The getErrorMessageLocator() method targets elements with slot="error-message", which is where Vaadin renders validation error messages in the shadow DOM.

Validation Attribute

Vaadin components indicate validation state through the invalid HTML attribute. When a component fails validation, the invalid attribute is set to an empty string (invalid=""). The assertValid() and assertInvalid() methods check for the presence or absence of this attribute.

Testing Patterns

Validation After User Input

// Trigger validation by blurring after input
field.setValue("test");
field.blur();
field.assertInvalid();

Server-Side Validation

// Submit form and wait for server validation
ButtonElement submit = ButtonElement.getByText(page, "Submit");
submit.click();

// Check for server-side validation errors
field.assertInvalid();
field.assertErrorMessage("This username is already taken");

Required Field Validation

// Test required field validation
field.setValue("");
field.blur();
field.assertInvalid();
field.assertErrorMessage("This field is required");

Related Interfaces

• HasInputFieldElement - Often composed with validation capabilities
• FocusableElement - Used to trigger validation via blur events