[BUG] Dash Testing: `wait_for_text_to_equal` may incorrectly succeed when used with text `"None"` about dash HOT 1 CLOSED

I was just coming to look into this further, but looks like I was beaten to it.

Looking at the function, I think there's a another solution. My thought would be to change

def __call__(self, driver): 
    try:  
        elem = self._get_element(driver) 
        logger.debug("text to equal {%s} => expected %s", elem.text, self.text) 
        value = elem.get_attribute("value")
        value = str(value) if value is not None else None
        return ( 
            str(elem.text) == self.text 
            or value == self.text 
        ) 

That way, the overall functionality of wait_for_text_to_equal doesn't change (except for the "None" case). The only downside is that it would pass if you use dash_duo.wait_for_text_to_equal("#my-div", None, timeout=4), but I don't know how often that would come up.

There is also an issue with wait_for_contains_text. The test

from dash import html
import dash


def test_wait_for_contains_text_none(dash_duo):

    app = dash.Dash(__name__)
    app.layout = html.Div(id="my-div", children="Hello world")
    dash_duo.start_server(app)
    dash_duo.wait_for_contains_text("#my-div", "No", timeout=4)

also passes, but similarly, there is no value and "No" is not in "Hello world".

There are potential issues with wait_for_contains_class and wait_for_class_to_equal, but I imagine those would be far less common.

from dash.