Minimum supported PHP version is 7.0

[agh1]

Overview

This actually changes the minimum PHP version to 7.0 from 5.6.

Before

You can install CiviCRM on a server with 5.6 or higher. A site on PHP 5.6 will have a warning status message saying, "This meets the minimum requirements for CiviCRM to function but is not recommended."

After

You can only install CiviCRM on a server with PHP 7.0 or higher. A site on PHP 5.6 will have an error status message saying, "To ensure the continued operation of CiviCRM, upgrade your server now." However, it will still be possible to upgrade CiviCRM on PHP 5.6.

Technical Details

This only changes CRM_Upgrade_Incremental_General::MIN_INSTALL_PHP_VER, and does not change CRM_Upgrade_Form::MINIMUM_PHP_VERSION. The former triggers status messages and the pre-install check, while the latter is the gatekeeper for upgrades.

Comments

I was asked to flag this in the release notes, but I noticed there actually wasn't any code change dropping PHP 5.6.

[civibot]

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[colemanw]

retest this please

[totten]

👍 on this incrementalism.

Tangentially... there are actually several "installers" (i.e. the typical D7/WP web-installer; the Joomla and drush and wp-cli installers; the setup.sh and civicrm_install() bash scripts) which each enforce different constraints, and those can be viewed as "stragglers" of another sort. We should eventually fix those too, but not by playing whack-a-mole specifically on the PHP version check. Rather, we should push forward on consolidating the installer code so that it's easier to maintain the installer logic generally.

But that's all tangential.

This PR seems like a fair and simple way to phase-in the elevated requirement.

[totten]

Notes:

• The test failure is unrelated.
• The PR tests still use PHP 5.6, but this passes anyway (because the patch only updates the GUI installer), so that change can be async.
• The demo sites (*.demo.civicrm.org) are already on PHP 7.x.
• I'll figure on how to update the hydra test sites.

[seamuslee001]

Test fail is unrelated given @totten's comments i'm going to merge this in