[augeas-devel] ruby-augeas: fine grained exceptions

[Ionuț Arțăriși]

Hello,

I would like to suggest a patch for the ruby augeas bindings to allow
for fine grained exceptions like the ones in the C code. 

I originally submitted this as a pull request on github[1], but seeing
as I got no response there, I will copy the content of that message here
as well:

I was annoyed at the fact that most augeas errors pass silently, only
returning an error code, which meant having to check after each command
if there actually was an error. I think that behaviour is very C-like
and not very ruby like. Instead I think the user should be prompted
immediately when an error happened and which kind of error it was.

This code does the following:

- raises ruby exceptions on error (these are the same as the ones in the
 C library, they have the same message, but their names were changed to
 be more suggestive (e.g. ECMDRUN -> CommandExecutionError)

- almost all commands are now declared in the ruby module and passed
through a run_command private method which checks for errors and raises
them (the corresponding methods from the C bindings file are now
private)

- a lot of new unit tests have been added for all the new errors and a
  few for normal invocation of methods which lacked unit tests before

There are some issues remaining, mostly around the load and save
commands which seem to have quite a different policy about errors
(1. storing them in the augeas tree, 2. returning success when failing
in case of load), but that should be a different issue.

Thanks!
-Ionuț


[1] https://github.com/lutter/ruby-augeas/pull/1