SurfSense/.cursor/skills/playwright-testing/testing-patterns/forms-validation.md
2026-05-10 04:19:55 +05:30

22 KiB

Form Testing Patterns

Table of Contents

  1. Quick Reference
  2. Patterns
  3. Decision Guide
  4. Anti-Patterns
  5. Troubleshooting

When to use: Testing form filling, submission, validation messages, multi-step wizards, dynamic fields, and auto-complete interactions.

Quick Reference

// Text input
await page.getByLabel("Username").fill("john_doe");

// Select dropdown
await page.getByLabel("Region").selectOption("EU");
await page.getByLabel("Region").selectOption({ label: "Europe" });

// Checkbox and radio
await page.getByLabel("Subscribe").check();
await page.getByLabel("Priority shipping").click();

// Date input
await page.getByLabel("Departure").fill("2025-08-20");

// Clear a field
await page.getByLabel("Username").clear();

// Submit
await page.getByRole("button", { name: "Register" }).click();

// Verify validation error
await expect(page.getByText("Username is required")).toBeVisible();

Patterns

Auto-Complete and Typeahead Fields

Use when: Testing search fields, address lookups, mention pickers, or any input that shows suggestions as the user types.

test("select from typeahead suggestions", async ({ page }) => {
  await page.goto("/products");

  const searchBox = page.getByRole("combobox", { name: "Find product" });
  await searchBox.pressSequentially("lapt", { delay: 100 });

  const suggestionList = page.getByRole("listbox");
  await expect(suggestionList).toBeVisible();

  await suggestionList.getByRole("option", { name: "Laptop Pro" }).click();
  await expect(searchBox).toHaveValue("Laptop Pro");
});

test("typeahead with API-driven suggestions", async ({ page }) => {
  await page.goto("/shipping");

  const streetField = page.getByLabel("Street");
  const responsePromise = page.waitForResponse("**/api/address-lookup*");
  await streetField.pressSequentially("456 Elm", { delay: 50 });

  await responsePromise;

  await page.getByRole("option", { name: /456 Elm St/ }).click();

  await expect(page.getByLabel("Town")).toHaveValue("Austin");
  await expect(page.getByLabel("State")).toHaveValue("TX");
  await expect(page.getByLabel("Postal code")).toHaveValue("78701");
});

test("dismiss suggestions and enter custom value", async ({ page }) => {
  await page.goto("/labels");

  const labelInput = page.getByLabel("New label");
  await labelInput.pressSequentially("my-label");

  await labelInput.press("Escape");
  await expect(page.getByRole("listbox")).not.toBeVisible();

  await labelInput.press("Enter");
  await expect(page.getByText("my-label")).toBeVisible();
});

Dynamic Forms — Conditional Fields

Use when: Form fields appear, disappear, or change based on the value of other fields.

test("conditional fields appear based on selection", async ({ page }) => {
  await page.goto("/loan/apply");

  await page.getByLabel("Applicant type").selectOption("corporate");

  await expect(page.getByLabel("Business name")).toBeVisible();
  await expect(page.getByLabel("EIN")).toBeVisible();

  await page.getByLabel("Business name").fill("TechCorp Inc");
  await page.getByLabel("EIN").fill("98-7654321");

  await page.getByLabel("Applicant type").selectOption("individual");
  await expect(page.getByLabel("Business name")).not.toBeVisible();
  await expect(page.getByLabel("EIN")).not.toBeVisible();
});

test("checkbox toggles additional section", async ({ page }) => {
  await page.goto("/delivery");

  await page.getByLabel("Separate invoice address").check();

  const invoiceSection = page.getByRole("group", { name: "Invoice address" });
  await expect(invoiceSection).toBeVisible();

  await invoiceSection.getByLabel("Address").fill("789 Pine Rd");
  await invoiceSection.getByLabel("City").fill("Denver");

  await page.getByLabel("Separate invoice address").uncheck();
  await expect(invoiceSection).not.toBeVisible();
});

test("dependent dropdown chains", async ({ page }) => {
  await page.goto("/region-selector");

  await page.getByLabel("Country").selectOption("CA");

  const provinceDropdown = page.getByLabel("Province");
  await expect(provinceDropdown.getByRole("option")).not.toHaveCount(0);

  await provinceDropdown.selectOption("ON");

  const cityDropdown = page.getByLabel("City");
  await expect(cityDropdown.getByRole("option")).not.toHaveCount(0);

  await cityDropdown.selectOption({ label: "Toronto" });
});

Multi-Step Forms and Wizards

Use when: The form spans multiple pages or steps, with next/previous navigation and per-step validation.

test("complete a multi-step booking wizard", async ({ page }) => {
  await page.goto("/booking");

  await test.step("enter guest information", async () => {
    await expect(
      page.getByRole("heading", { name: "Guest Info" }),
    ).toBeVisible();

    await page.getByLabel("Full name").fill("Alice Smith");
    await page.getByLabel("Email").fill("alice@test.com");
    await page.getByLabel("Phone").fill("555-1234");

    await page.getByRole("button", { name: "Next" }).click();
  });

  await test.step("select room options", async () => {
    await expect(
      page.getByRole("heading", { name: "Room Selection" }),
    ).toBeVisible();

    await page.getByLabel("Room type").selectOption("suite");
    await page.getByLabel("Check-in").fill("2025-09-01");
    await page.getByLabel("Check-out").fill("2025-09-05");

    await page.getByRole("button", { name: "Next" }).click();
  });

  await test.step("confirm booking", async () => {
    await expect(
      page.getByRole("heading", { name: "Confirmation" }),
    ).toBeVisible();

    await expect(page.getByText("Alice Smith")).toBeVisible();
    await expect(page.getByText("suite")).toBeVisible();

    await page.getByRole("button", { name: "Confirm booking" }).click();
  });

  await expect(
    page.getByRole("heading", { name: "Booking complete" }),
  ).toBeVisible();
});

test("wizard validates each step before proceeding", async ({ page }) => {
  await page.goto("/booking");

  await page.getByRole("button", { name: "Next" }).click();

  await expect(page.getByRole("heading", { name: "Guest Info" })).toBeVisible();
  await expect(page.getByText("Full name is required")).toBeVisible();
});

test("wizard supports going back without losing data", async ({ page }) => {
  await page.goto("/booking");

  await page.getByLabel("Full name").fill("Alice Smith");
  await page.getByLabel("Email").fill("alice@test.com");
  await page.getByLabel("Phone").fill("555-1234");
  await page.getByRole("button", { name: "Next" }).click();

  await page.getByRole("button", { name: "Previous" }).click();

  await expect(page.getByLabel("Full name")).toHaveValue("Alice Smith");
  await expect(page.getByLabel("Email")).toHaveValue("alice@test.com");
});

Form Submission and Response Handling

Use when: Testing what happens after a form is submitted — success messages, redirects, error responses from the server, and loading states during submission.

test("successful form submission shows confirmation", async ({ page }) => {
  await page.goto("/feedback");

  await page.getByLabel("Subject").fill("Feature request");
  await page.getByLabel("Email").fill("user@test.com");
  await page.getByLabel("Details").fill("Please add dark mode");

  const responsePromise = page.waitForResponse("**/api/feedback");
  await page.getByRole("button", { name: "Submit feedback" }).click();
  const response = await responsePromise;

  expect(response.status()).toBe(200);
  await expect(page.getByText("Feedback received")).toBeVisible();
});

test("form submission shows server-side validation errors", async ({
  page,
}) => {
  await page.goto("/signup");

  await page.getByLabel("Email").fill("existing@test.com");
  await page.getByLabel("Password", { exact: true }).fill("Secure1@pass");
  await page.getByRole("button", { name: "Sign up" }).click();

  await expect(
    page.getByText("Email address already registered"),
  ).toBeVisible();
});

test("form shows loading state during submission", async ({ page }) => {
  await page.goto("/feedback");

  await page.getByLabel("Subject").fill("Bug report");
  await page.getByLabel("Email").fill("user@test.com");
  await page.getByLabel("Details").fill("Found an issue");

  const submit = page.getByRole("button", {
    name: /Submit feedback|Submitting/,
  });
  await submit.click();

  await expect(submit).toHaveText(/Submitting/);
  await expect(submit).toBeDisabled();

  await expect(submit).toHaveText("Submit feedback");
  await expect(submit).toBeEnabled();
});

test("form redirects after successful submission", async ({ page }) => {
  await page.goto("/auth/login");

  await page.getByLabel("Email").fill("admin@test.com");
  await page.getByLabel("Password").fill("admin123");
  await page.getByRole("button", { name: "Log in" }).click();

  await page.waitForURL("/home");
  await expect(page.getByRole("heading", { name: "Welcome" })).toBeVisible();
});

Filling Basic Form Fields

Use when: Testing any form with standard HTML inputs — text, email, password, number, textarea, select, checkbox, radio.

test("fill and submit a signup form", async ({ page }) => {
  await page.goto("/signup");

  await page.getByLabel("First name").fill("Bob");
  await page.getByLabel("Last name").fill("Wilson");
  await page.getByLabel("Email").fill("bob@test.com");
  await page.getByLabel("Password", { exact: true }).fill("P@ssw0rd!");
  await page.getByLabel("Confirm password").fill("P@ssw0rd!");

  await page.getByLabel("About you").fill("Developer with 5 years experience.");
  await page.getByLabel("Years of experience").fill("5");

  await page.getByLabel("Country").selectOption("UK");
  await page.getByLabel("City").selectOption({ label: "London" });
  await page
    .getByLabel("Skills")
    .selectOption(["typescript", "playwright", "nodejs"]);

  await page.getByLabel("Accept terms").check();
  await expect(page.getByLabel("Accept terms")).toBeChecked();

  await page.getByLabel("Annual billing").check();
  await expect(page.getByLabel("Annual billing")).toBeChecked();

  await page.getByRole("button", { name: "Create account" }).click();
  await expect(page.getByRole("heading", { name: "Welcome" })).toBeVisible();
});

Date and Time Inputs

Use when: Testing native <input type="date">, <input type="time">, <input type="datetime-local">, or third-party date pickers.

test("fill native date and time inputs", async ({ page }) => {
  await page.goto("/reservation");

  await page.getByLabel("Reservation date").fill("2025-07-10");
  await expect(page.getByLabel("Reservation date")).toHaveValue("2025-07-10");

  await page.getByLabel("Time slot").fill("18:00");
  await page.getByLabel("Reminder").fill("2025-07-10T17:30");
});

test("interact with a third-party date picker", async ({ page }) => {
  await page.goto("/reservation");

  await page.getByLabel("Event date").click();
  await page.getByRole("button", { name: "Next month" }).click();
  await page.getByRole("gridcell", { name: "25" }).click();

  await expect(page.getByLabel("Event date")).toHaveValue(/2025/);
});

Required Field Validation

Use when: Testing that the form shows appropriate error messages when required fields are empty.

test("shows validation errors for empty required fields", async ({ page }) => {
  await page.goto("/inquiry");

  await page.getByRole("button", { name: "Send inquiry" }).click();

  await expect(page.getByText("Name is required")).toBeVisible();
  await expect(page.getByText("Email is required")).toBeVisible();
  await expect(page.getByText("Question is required")).toBeVisible();

  await expect(page).toHaveURL(/\/inquiry/);
});

test("clears validation errors when fields are filled", async ({ page }) => {
  await page.goto("/inquiry");

  await page.getByRole("button", { name: "Send inquiry" }).click();
  await expect(page.getByText("Name is required")).toBeVisible();

  await page.getByLabel("Name").fill("Carol Brown");
  await page.getByLabel("Email").focus();

  await expect(page.getByText("Name is required")).not.toBeVisible();
});

test("native HTML5 validation with required attribute", async ({ page }) => {
  await page.goto("/basic-form");

  await page.getByRole("button", { name: "Submit" }).click();

  const emailInput = page.getByLabel("Email");
  const validationMessage = await emailInput.evaluate(
    (el: HTMLInputElement) => el.validationMessage,
  );
  expect(validationMessage).toBeTruthy();
});

Format Validation and Custom Rules

Use when: Testing email format, phone number format, password strength, and business-specific validation rules.

test("validates email format", async ({ page }) => {
  await page.goto("/signup");

  const emailField = page.getByLabel("Email");

  const invalidEmails = [
    "invalid",
    "missing@",
    "@nodomain.com",
    "has spaces@mail.com",
  ];

  for (const email of invalidEmails) {
    await emailField.fill(email);
    await emailField.blur();
    await expect(page.getByText("Enter a valid email address")).toBeVisible();
  }

  await emailField.fill("correct@domain.com");
  await emailField.blur();
  await expect(page.getByText("Enter a valid email address")).not.toBeVisible();
});

test("validates password strength rules", async ({ page }) => {
  await page.goto("/signup");

  const passwordField = page.getByLabel("Password", { exact: true });

  await passwordField.fill("Xy1!");
  await passwordField.blur();
  await expect(page.getByText("Minimum 8 characters")).toBeVisible();

  await passwordField.fill("lowercase1!");
  await passwordField.blur();
  await expect(page.getByText("Include an uppercase letter")).toBeVisible();

  await passwordField.fill("SecureP@ss1");
  await passwordField.blur();
  await expect(page.getByText(/Minimum|Include/)).not.toBeVisible();
});

test("validates custom business rule — minimum amount", async ({ page }) => {
  await page.goto("/transfer");

  await page.getByLabel("Amount").fill("5");
  await page.getByLabel("Amount").blur();
  await expect(page.getByText("Minimum transfer is $10")).toBeVisible();

  await page.getByLabel("Amount").fill("1000000");
  await page.getByLabel("Amount").blur();
  await expect(page.getByText("Maximum transfer is $100,000")).toBeVisible();

  await page.getByLabel("Amount").fill("500");
  await page.getByLabel("Amount").blur();
  await expect(page.getByText(/Minimum|Maximum/)).not.toBeVisible();
});

Form Reset Testing

Use when: Testing "clear form" or "reset" functionality, verifying that fields return to their default values.

test("reset button clears all fields to defaults", async ({ page }) => {
  await page.goto("/preferences");

  await page.getByLabel("Nickname").fill("CustomNick");
  await page.getByLabel("Language").selectOption("es");
  await page.getByLabel("Email alerts").uncheck();

  await page.getByRole("button", { name: "Reset" }).click();

  await expect(page.getByLabel("Nickname")).toHaveValue("");
  await expect(page.getByLabel("Language")).toHaveValue("en");
  await expect(page.getByLabel("Email alerts")).toBeChecked();
});

test("confirmation dialog before resetting a dirty form", async ({ page }) => {
  await page.goto("/document");

  await page.getByLabel("Document title").fill("Draft document");

  page.on("dialog", (dialog) => dialog.accept());
  await page.getByRole("button", { name: "Clear changes" }).click();

  await expect(page.getByLabel("Document title")).toHaveValue("");
});

Decision Guide

Scenario Approach Key API
Standard text input fill() (clears, then types) page.getByLabel('Field').fill('value')
Need keystroke events (autocomplete) pressSequentially() with delay locator.pressSequentially('text', { delay: 100 })
Native <select> dropdown selectOption() by value or label locator.selectOption('US') or { label: 'United States' }
Custom dropdown (ARIA listbox) Click trigger, then select option role getByRole('option', { name: '...' }).click()
Checkbox check() / uncheck() (idempotent) locator.check() — safe to call even if already checked
Radio button check() on the target radio page.getByLabel('Option').check()
Date input (native) fill() with ISO format locator.fill('2025-03-15')
Date picker (third-party) Click to open, navigate, select day getByRole('gridcell', { name: '15' }).click()
Validation errors Submit, then assert error text expect(page.getByText('Required')).toBeVisible()
Multi-step wizard test.step() per step, assert heading await test.step('Step 1', async () => { ... })
Conditional/dynamic fields Change trigger field, assert new field visibility expect(locator).toBeVisible() / .not.toBeVisible()
Form submission waitForResponse + click submit Register response listener before click
Auto-complete pressSequentially(), wait for listbox, select option getByRole('option', { name }).click()
Form reset Click reset, assert default values expect(locator).toHaveValue('')

Anti-Patterns

Don't Do This Problem Do This Instead
await page.getByLabel('Field').type('value') type() appends to existing content; does not clear first await page.getByLabel('Field').fill('value')
await page.getByLabel('Option').click() click() toggles — if already checked, it unchecks await page.getByLabel('Option').check()
await page.fill('#email', 'test@test.com') CSS selector is fragile await page.getByLabel('Email').fill('test@test.com')
await page.selectOption('select', 'US') without label Targets first <select> on page; ambiguous await page.getByLabel('Country').selectOption('US')
Testing every invalid input in one test Test becomes huge, slow, and hard to debug One test per validation rule or group related rules
expect(await input.inputValue()).toBe('value') Resolves once — no retry. Race condition. await expect(input).toHaveValue('value')
Filling fields with page.evaluate() Bypasses event handlers (no input, change events fire) Use fill() or pressSequentially()
Not waiting for conditional fields before filling fill() fails on hidden/detached elements await expect(field).toBeVisible() first
Hardcoding wait after selecting a dropdown waitForTimeout(500) is flaky and slow Wait for the dependent element to appear
Skipping server-side validation tests Client-side validation can be bypassed Test both client-side UX and server response

Troubleshooting

fill() does nothing or clears but doesn't type

Cause: The input field uses a contenteditable div (rich text editors), not a real <input> or <textarea>.

const isContentEditable = await page
  .getByTestId("editor")
  .evaluate((el) => el.getAttribute("contenteditable"));

if (isContentEditable) {
  await page.getByTestId("editor").click();
  await page.getByTestId("editor").pressSequentially("Hello world");
}

Date picker does not accept fill() value

Cause: Third-party date pickers often render custom UI over a hidden input. fill() sets the hidden input but the UI does not update.

await page.getByLabel("Date").click();
await page.getByRole("button", { name: "Next month" }).click();
await page.getByRole("gridcell", { name: "15" }).click();

// Alternatively, if the library reads from the input on change:
await page.getByLabel("Date").fill("2025-06-15");
await page.getByLabel("Date").dispatchEvent("change");

selectOption() throws "not a select element"

Cause: The dropdown is a custom component (ARIA listbox), not a native <select>.

await page.getByRole("combobox", { name: "Country" }).click();
await page.getByRole("option", { name: "United States" }).click();

Validation errors do not appear after fill() and submit

Cause: The validation triggers on blur (focus leaving the field), but fill() does not trigger blur automatically.

await page.getByLabel("Email").fill("invalid");
await page.getByLabel("Email").blur();
await expect(page.getByText("Enter a valid email")).toBeVisible();

// Or move focus to the next field
await page.getByLabel("Password").focus();