JavaScript dialogs are fairly common in web applications.

Watir-WebDriver has an inbuilt library for handling the dialogs, and capturing values from the dialogs.

JavaScript Alerts

# Check if alert is shown
browser.alert.exists?

# Get text of alert
browser.alert.text

# Close alert
browser.alert.ok
browser.alert.close

JavaScript Confirms

# Accept confirm
browser.alert.ok

# Cancel confirm
browser.alert.close

JavaScript Prompt

# Enter text to prompt
browser.alert.set "Prompt answer"

# Accept prompt
browser.alert.ok

# Cancel prompt
browser.alert.close

Alternative Method

If you’re having trouble using the above method, you can override the JavaScript functions to return the value you want, so when they’re meant to show, they don’t!

# don't return anything for alert
browser.execute_script("window.alert = function() {}")

# return some string for prompt to simulate user entering it
browser.execute_script("window.prompt = function() {return 'my name'}")

# return null for prompt to simulate clicking Cancel
browser.execute_script("window.prompt = function() {return null}")

# return true for confirm to simulate clicking OK
browser.execute_script("window.confirm = function() {return true}")

# return false for confirm to simulate clicking Cancel
browser.execute_script("window.confirm = function() {return false}")

# don't return anything for leave page popup
browser.execute_script("window.onbeforeunload = null")