There was a problem with core\update\code_manager::unzip_plugin_file()
if it was used to extract a plugin package into a non-empty target
directory and the plugin package root folder was being renamed at the
same time.
The problem was caused by the underlying helper method
rename_extracted_rootdir() that worked only for ZIPs extracted to an
empty temporary location. When the plugin was extracted to the actual
dirroot with other existing plugin folders present, the method failed
badly.
The solution in the patch is to always extract the ZIP into a temporary
empty location, perform the eventual root renaming there, and only then
move the extracted contents to the final destination. Additionally we
are changing the behaviour of the rename_extracted_rootdir() method so
that now it throws exception if the plugin package contains multiple
root folders (it should not happen in normal situations as such a plugin
would not pass the pre-install validation).
Unit tests did not catch this bug before because in the tests, the
target directory had been empty. Now we are adding a new directory
"aaa_another" to the target location to test in more realistic
environment. Tests for the new behaviour of the renaming method are
added, too.
p.s. I noticed that moodle_exception class was not imported into the
namespace and this is fixed now too (and covered with unit tests).
The method move_plugin_directory() was a relict from previous 2.9
implementation within tool_installadon_installer and was originally
supposed to be used to move whole plugin folders. The archiving feature
has been finally implemented via using zip files (so that we do not have
actual PHP code present in the dataroot) and we do not need this method.
This should allow the admin to revert the upgrade of existing plugins,
such when the dependency chain leads to a dead-end. Additionally, we
archive (as a last-chance copy) the to-be-installed plugins when
cancelling their installation. This is mainly for developers who could
otherwise loose their code. For the same reason, plugins are being
archived upon uninstallation, too.
The plugin manager's method install_remote_plugins() has been changed to
install_plugins() and it is now able to install plugins from the
provided list of locally available ZIP files, too. This is used by the
Install plugins admin tool.
The plan is to have a single tool looking after all operations with
plugin ZIP packages (downloading, unzipping, moving to the dirroot and
back). For legacy reasons, we have that logic currently duplicated in
mdeploy and tool_installaddon. I would like to unify and simplify the
whole machinery to use the same code for available updates, manual
installation and plugin dependencies.