I'm trying to upgrade a site from 2.3.4 to either 2.3.5 or 2.4. but It won't pass the readiness check.
If I try to upgrade to 2.3.5 It just says there are conflicts but doesn't tell me what & if I try to upgrade to 2.4 it tells me that my php version is either too high or too low.
I have tried php 7.1 through 7.4 both in the front end & backend for both upgrades but no joy & also tried upgrading via ssh.
It would appear that its because composer needs updating but when try to update it via ssh I get this error message.
-bash-4.2$ composer require magento/composer-root-update-plugin=~1.0 --no-update
PHP Warning: Unsupported declare 'strict_types' in .................................../vendor/magento/inventory-composer-installer/src/Plugin.php on line 6
Warning: Unsupported declare 'strict_types' in .................................../vendor/magento/inventory-composer-installer/src/Plugin.php on line 6
PHP Parse error: syntax error, unexpected ':', expecting ';' or '{' in ................................../vendor/magento/inventory-composer-installer/src/Plugin.php on line 55
Parse error: syntax error, unexpected ':', expecting ';' or '{' in .................................../vendor/magento/inventory-composer-installer/src/Plugin.php on line 55
A search for this error again suggests that its because Im not using the correct php version but again I have tried php 7.1 through 7.4 ( I know the php version is correct by using php -v)
Updated other sites no problem but this is the only site which had the demo data installed.
