Robottelo: Create specialized type for locators allowing direct interpolation

[rochacbruno]

Currently to define a locator we use a tuple formed by strategy and locator_path:

"get.element.by.link": (By.XPATH, "//a[contains(@href, '%s')]")

The problem is that the code turn verbose when we need to interpolate %s in the locator_path we should do.

strategy, value = locators['get.element.by.link']
self.click((strategy, value % 'foo/bar'))

We can just create a specialized type from tuple as

class Locator(tuple):
    """A tuple that allows direct interpolation of second element"""
    def __mod__(self, data):
        strategy, value = self
        return strategy, value % data

We should use the above type instead of a tuple in locators:

"get.element.by.link": Locator(By.XPATH, "//a[contains(@href, '%s')]")

and then we can do direct interpolation, saving us of defining extra strategy, value variables everytime

self.click(locators['get.element.by.link'] % 'foo/bar')

[rochacbruno]

Also I found that in logs we get this:

2016-07-14 13:03:25 - robottelo.ui.locators - DEBUG - Accessing locator "contenthost.bulk_actions.via_katello_agent" by xpath: "//a[contains(@ng-click, "performViaKatelloAgent('%s', content)")]"

Look the %s in logs is not very informative, so if we specialize the Location tuple we can add a DEBUG message in the interpolation to help us figuring out exactly which locator is being accessed.

[rochacbruno]

Comment from IRC by @elyezer

a even less verbose approach would be locators.get_element_by_link also if they are converted to attributes autocomplete can work pretty well

Nice idea I'll experiment turning locators in to models and instead of keys we use atrtibutes

(BTW: trying to keeping the current approach working with no breaks)