Diff must execute before Revisioning to prevent access denied errors

Updated: Comment #0

Problem/Motivation

If the Diff module executes after the Revisioning module, then Diff wreaks havoc with the menu router causing access denied errors when trying to access node revisions. Currently, both Diff and Revisioning have a wight of 0, so they are executed according to the alphabetical order of their file paths.

Admittedly this is not always a problem, since 'd' comes before 'r'. However, that is an unreliable solution. For instance, if Revisioning were included in an installation profile, but Diff was added in the sites directory, then you would trigger the error since "profiles" comes before "sites". Likewise if you have a multi-site setup with Revisioning in sites/all/ and Diff in sites/mydomain.com/. Or if you patch Diff and move it to sites/all/patched/, which would then execute after anything in sites/all/contrib/. All of these are potential real-world use cases.

Proposed resolution

Either the menu functions in Diff need to be updated so they don't conflict with Revisioning, or the weight of Diff in the system table needs to be changed to -1, so it will always execute before Revisioning.

Note that it is not possible to increase Revisioning's weight, as that would cause a conflict with the Workflow module and they are often used together.

Remaining tasks

Decide on preferred solution and implement it.

User interface changes

None.

API changes

None.