PHPUnit tests on Windows

[danielhuesken]

We can get more PHP unit tests work under windows system if files wil not created in /temp and symlinks will not be used.

[netweb]

Related, possible duplicate of #39975

The patch in #39975 appears to cover a few more instances of /tmp usage in the codebase.

@danielhuesken The [symlink ​https://secure.php.net/manual/en/function.symlink.php] function is avialble on Windows with PHP 5.3 or greater, can I ask what issues you're having with symlink on Windows?

[danielhuesken]

@netweb Yes, there are supported but with limitations minimum Windows Version is Windows Vista or Server 2008 and you must use NTFS File System.

I use Windows 10 with NTFS (Apache, PHP 7.1) and they will not work. There error message is "Warning: symlink(): Cannot create symlink, error code(1314)" it should be Permission related. See ​https://bugs.php.net/bug.php?id=54141.

I think that are many things you must know to run test on windows correctly.

[davidbaumwald]

Latest patch fails against trunk, so marking for a refresh.

[SergeyBiryukov]

In 48463:

Tests: Copy themes from tests/phpunit/data to wp-content/themes, instead of creating a symlink.

This allows the theme file tests in phpunit/tests/link/themeFile.php to run on Windows without requiring administrative privileges.

Follow-up to [42812], [42819].

Props danielhuesken, christophherr, davidbaumwald, SergeyBiryukov.
See #40856, #39975.

[SergeyBiryukov]

In 48464:

Tests: Replace hardcoded /tmp/ references with get_temp_dir().

This allows more tests to pass on Windows.

Props danielhuesken, DJPaul, christophherr, joemcgill, netweb, davidbaumwald, SergeyBiryukov.
Fixes #40856, #39975.

[SergeyBiryukov]

Follow-up: #50664