Selenium Expected Conditions - possible to use 'or'?

Question

I\'m using Selenium 2 / WebDriver with the Python API, as follows:

from selenium.webdriver.support import expected_conditions as EC

# code that causes an aj         


        

Answer 1

Ancient question but,

Consider how WedDriverWait works, in an example independent from selenium:

def is_even(n):
    return n % 2 == 0

x = 10

WebDriverWait(x, 5).until(is_even)

This will wait up to 5 seconds for is_even(x) to return True

now, WebDriverWait(7, 5).until(is_even) will take 5 seconds and them raise a TimeoutException

Turns out, you can return any non Falsy value and capture it:

def return_if_even(n):
    if n % 2 == 0:
        return n
    else:
        return False

x = 10
y = WebDriverWait(x, 5).until(return_if_even)
print(y) # >> 10

Now consider how the methods of EC works:

print(By.CSS_SELECTOR) # first note this is only a string
>> 'css selector'

cond = EC.presence_of_element_located( ('css selector', 'div.some_result') )
# this is only a function(*ish), and you can call it right away:

cond(driver)
# if element is in page, returns the element, raise an exception otherwise

You probably would want to try something like:

def presence_of_any_element_located(parent, *selectors):
    ecs = []
    for selector in selectors:
        ecs.append(
            EC.presence_of_element_located( ('css selector', selector) )
        )

     # Execute the 'EC' functions agains 'parent'
     ecs = [ec(parent) for ec in ecs]

     return any(ecs)

this WOULD work if EC.presence_of_element_located returned False when selector not found in parent, but it raises an exception, an easy-to-understand workaround would be:

def element_in_parent(parent, selector):
    matches = parent.find_elements_by_css_selector(selector)
    if len(matches) == 0:
        return False
    else:
        return matches

def any_element_in_parent(parent, *selectors):
    for selector in selectors:
        matches = element_in_parent(parent, selector)
        # if there is a match, return right away
        if matches:
            return matches
    # If list was exhausted
    return False

# let's try 
any_element_in_parent(driver, 'div.some_result', 'div.no_result')
# if found in driver, will return matches, else, return False

# For convenience, let's make a version wich takes a tuple containing the arguments (either one works):
cond = lambda args: any_element_in_parent(*args)
cond( (driver, 'div.some_result', 'div.no_result') )
# exactly same result as above

# At last, wait up until 5 seconds for it 
WebDriverWait((driver, 'div.some_result', 'div.no_result'), 5).until(cond)

My goal was to explain, artfulrobot already gave a snippet for general use of actual EC methods, just note that

class A(object):
    def __init__(...): pass
    def __call__(...): pass

Is just a more flexible way to define functions (actually, a 'function-like', but that's irrelevant in this context)