WP Test Suite utils: is_post_type_viewable() is used, but might not be defined

[tyxla]

In _cleanup_query_vars() in the WordPress test suite utils.php, the is_post_type_viewable() function is used to assure that only the viewable post type query vars are added.

This is fine and makes perfect sense, but since is_post_type_viewable() is a new function (introduced in [33666]), it is not available in 4.3 and older versions. This basically ruins backward compatibility, and prevents testing 4.3 and older versions.

This is particularly an issue if running tests for a WordPress plugin or theme with any CI tool (like Travis) and testing with the following env config in .travis.yml:

env:
  - WP_VERSION=4.3 WP_MULTISITE=0
  - WP_VERSION=4.2 WP_MULTISITE=0
  - WP_VERSION=4.1 WP_MULTISITE=0
  - WP_VERSION=4.0 WP_MULTISITE=0

The problematic modification appears to have been introduced in [34215], a little more than an hour ago.

[ocean90]

Why are you using the tests of trunk and not the tests from the specific branches?

[tyxla]

@ocean90: good point, thanks.

[jdgrimes]

Replying to ocean90:

Why are you using the tests of trunk and not the tests from the specific branches?

Because the tests in trunk may have added sugar that isn't in the older branches. Yes, it may make more sense to test with the tests from the same branch, but this is currently the convention used across a wide range of plugins.

[boonebgorges]

Replying to jdgrimes:

Replying to ocean90:

Why are you using the tests of trunk and not the tests from the specific branches?

Because the tests in trunk may have added sugar that isn't in the older branches. Yes, it may make more sense to test with the tests from the same branch, but this is currently the convention used across a wide range of plugins.

I'm the author of a number of plugins that leverage core tests in the way described here. But it's my responsibility as a plugin author to provide necessary shims/compat functions in cases where my tests need them. The alternative is for the core utils not to use new functions for a specified number of versions (how many? one? three?), which doesn't seem reasonable to me.