Fix pkg cache test

[davidlatwe]

• Package.is_cachable may not return correct setting when config.default_cachable_per_repository is set and the paths it contains is not canonical, like when filesystem is slash/case-insensitive (Windows).
• TestPackageCache.test_caching_on_resolve can only get passed in production install due to ResolvedContext will not trigger cache update if that is not the case.

[davidlatwe]

Actually, would it be better if we make path canonical right after it's loaded here ?
https://github.com/nerdvegas/rez/blob/629f446f228873f74e0fef5e594d8d2c06ef1f00/src/rez/config.py#L681-L689

Like :

    @cached_property
    def _data(self):
        data = copy.deepcopy(self._data_without_overrides)

        # need to do this regardless of overrides, in order to flatten
        # ModifyList instances
        deep_update(data, self.overrides)

        if data["default_cachable_per_repository"]:
            canonised = dict()
            for path, value in data["default_cachable_per_repository"].items():
                canonised[canonical_path(path)] = value
            data["default_cachable_per_repository"] = canonised

        return data

And maybe we could also do this for other filesystem path related config settings ?

[davidlatwe]

Actually, would it be better if we make path canonical right after it's loaded here ?

Sorry, I think for now I'll just focusing on fixing tests.

[davidlatwe]

The last commit is for fixing TestCommands.test_py along with others that are testing rex.Action, and some of the actions have filesystem path involved like, Setenv which may also fail if the testing path is not canonical.

As an example, see part of my test report below :

-  Setenv('REXTEST_DIRS', EscapedString([(False, 'c:\\users\\...\src\\rez\\tests\\data\\commands\\packages\\rextest\\1.3/data')])),
?                         ----------------------- ^   ^                                                                        ---

+  Setenv('REXTEST_DIRS', 'C:\\Users\\...\\src\\rez\\tests\\data\\commands\\packages\\rextest\\1.3/data'),
?                          ^   ^

[nerdvegas]

Hey David, I'll merge this but I think we're bandaiding the real issue somewhat.

I agree that we should be converting to canonical paths at config load time (well, during its lazy validation anyway) as you've suggested. However you wouldn't do it as shown in your snippet - instead you'd do it using a Setting-subclassed validator (as per examples in config.py), so you don't get the cost of canonicising paths at config load time.

In terms of the issue you've found in (eg) setenv - that's trickier because you can't know whether a string being used in setenv is representing a path or not, even if it looks like one. To properly solve this I think we'd have to introduce another built in construct, for eg something like:

def commands():
    env.MY_PATHY_VALUE = as_path("/svr/stuff.txt")

[davidlatwe]

instead you'd do it using a Setting-subclassed validator (as per examples in config.py), so you don't get the cost of canonicising paths at config load time.

Ah yes, that sounds much better !

To properly solve this I think we'd have to introduce another built in construct

That sounds good too, will have a look into that. :)