tests for is_php_version_compatible and is_wp_version_compatible

Trac ticket:

[hellofromTonya]

5.9 is in Feature Freeze and focus is on defects. With less than a week until Beta 1, there's likely not time to in the 5.9 cycle to focus on these tests.

I'm moving it to the next release cycle. As tests can be committed at anytime into trunk, if someone has the time to get review and get this patch committed, please do so. Else, let's get it done early in 6.0.

@pbearne If I remove the changes in package-lock.json, it will be possible to merge it.

[pbearne]

refreshed pull request

[peterwilsoncc]

In 53227:

Build, Test Tools: Test PHP and WP compatibility functions.

Introduce tests for is_php_version_compatible() and is_wp_version_compatible().

Props pbearne, hellofromTonya, mikeschroder, peterwilsoncc, toro_unit.
Fixes #54257.

Committed in https://core.trac.wordpress.org/changeset/53227

[costdev]

Patch 54257.1.diff updates the tests introduced in [53227] to:

• fix an incorrect function name in the documentation.
• use consistent documentation within the test suite.
• improve readability.
• remove spaces between increment/decrement operators per ​proposed coding standards changes.
• use informative argument and variable names.
• add public visibility to the data providers.
• add tests to cover falsey values.
• add tests to cover alpha and beta versions.
• remove an unnecessary call to get_bloginfo(), as this simply returns the value of $wp_version.

In addition:

• Changing this from bug (defect) to task (blessed) as it is a tests-only ticket.
• Changing this from the Plugins component to Build/Test Tools:
  • These functions can be used with respect to both plugins and themes.
  • Tests are within the scope of Test Tools.
  • This helps with queries to find test-only tickets, whereas the has-unit-tests keyword can be applied to any ticket.

[costdev]

54257.1.2.diff adds RC datasets for completeness.

[SergeyBiryukov]

54257.1.2.diff​ looks great to me.

54257.2.diff​ includes a few more changes to further clarify the variable names, use a consistent approach for adjusting the higher and lower version numbers, and reduce the number of implode() calls.

[costdev]

Nice updates @SergeyBiryukov! The patch looks good to me.

[SergeyBiryukov]

Use correct variable in the last data provider

[peterwilsoncc]

In 53237:

Tests, Build Tools: Improve version compatibility tests.

Improve tests for is_wp_version_compatible() and is_php_version_compatible().

Follow up to [53227].

Props costdev, SergeyBiryukov.
Fixes #54257.