drush_invoke does not respect 'callback' property

You are correct; drush_invoke does not do a full dispatch of the command. It does not support the callback function, and it does not apply command-specific options.

For your purpose, it would be better to call drush_dispatch instead. This function will support the callback function, apply command-specific options, and so on.

The unfortunate thing about this situation is that drush_dispatch is less convenient to call than drush_invoke in that it takes a command array instead of a command name, as drush_invoke does, and it takes a few awkward lines for the client to look up the command record first. We could make things better in drush-5 and even in drush-4.6 by adding this lookup code to the head of drush_dispatch, as shown in the attached patch.

@andreiashu: Make sure that drush_invoke / drush_dispatch are really the functions you intend to call. These functions are for use in cases where you want to create a compound command that dispatches to other drush commands that run with the arguments and options the user specified on the command line. If you want to run a command using the arguments and options that you specify in your function, drush_invoke_process is preferable. Use '@self' for the site alias record parameter to run on the bootstrapped site.

I'm on the fence about this change. It is a little ugly for dispatch to take a string or an array. Also, I like the name correlation between drush_invoke and drush_invoke_process. drush_dispatch() and drush_invoke_process() don't hang together as well.

Moving command-specific options to drush_invoke would not work well; ditto for support of the 'callback' function. Renaming drush_dispatch to drush_invoke would be inadvisable. If we wish to keep drush_invoke as the preferred entrypoint for local dispatches, then we have to live with its limitations, I think.

i think i am ok with status quo.

Maybe I was too hasty in #3.

The attached patch changes drush_invoke to call through to drush_dispatch. drush_dispatch remains unchanged. The old drush_invoke is renamed to _drush_invoke_hooks, an internal-only function.

This change might subtly affect some drush commands, but all test cases pass, and overall I think it is an improvement (drush_invoke behaves consistently, and can now be used with commands that use a callback).

If this looks good, I will fix up the comments to match the new code. It might also be a good idea to stop overloading $command['arguements'], maybe renaming the cli arguements to 'args' or 'cli-args' to minimize the impact.

Looks good to me too. If you grep around and more or less verify that existing calls are OK, go ahead and commit.

Existing commands in Drush core are okay; there is some small chance that contrib commands may be affected, which is what I was referring to in #5. I have added a change record for this issue & committed to master.

Not eligible for back-port.

Hm, I thought that change records are linked to from their respective issues. Guess not. The change record is here: http://drupal.org/node/1359038