Theme unit tests fail if a child theme is present

[johnbillion]

If you place a child theme into your theme directory, the Tests_Theme::test_switch_theme() test will fail.

1) Tests_Theme::test_switch_theme
Failed asserting that two strings are equal.
--- Expected
+++ Actual
@@ @@
-'My Child Theme'
+'Twenty Fifteen'

~/tests/phpunit/tests/theme.php:224

Needs investigating.

[obenland]

I noticed that too, been wanting to investigate that.

[obenland]

Unit tests are failing because if template and stylesheet are passed to switch_theme(), $new_theme gets set before the second argument is appropriately handled, causing 'current_theme' to always be updated to the parent theme's name.

Introduced in [21131].

[obenland]

32635.diff​ sets $stylesheet to the second argument when available, always sets $template to the template property of the theme's WP_Theme.

[wonderboymusic]

32635.2.diff​ should do it

[obenland]

In 33815:

Themes: Get the correct theme when template and stylesheet were both passed as arguments.

Fixes a bug where $new_theme got set before the second argument was
appropriately handled, causing the current_theme option to later always be
updated to the parent theme's name.

Introduced in [21131].

Props obenland, wonderboymusic.
Fixes #32635.