changed missing file error to warning for lookups

[bcoca]

ISSUE TYPE

• Bugfix Pull Request

ANSIBLE VERSION

2.2

SUMMARY

This should reestablish the old behavior skipping loops instead of creating errors.

fixes #16801

[mattclay]

@bcoca This change breaks with_first_found. The test is failing because the task test with_first_found in test_iterators is now returning null instead of the first item found.

[bcoca]

is test correct? this change avoids an exception that ends up giving back 'the first item' from first found, not actually that it found the file

[mattclay]

The test is correct: https://github.com/ansible/ansible/blob/devel/test/integration/roles/test_iterators/tasks/main.yml#L187

Also, there are other tests failing from this change: https://app.shippable.com/runs/57dab579eef88d1000043437/12/console

That one fails on an include using with_first_found to find the path when the file doesn't exist.

[bcoca]

That one fails on an include using with_first_found to find the path when the file doesn't exist.

Isn't that the point? nvmd, misunderstood, fixed the lookup to not ignore the exception but deal with the None.