When custom dictionary is used to create a completer, rlcompleter still
uses __builtins__.__dict__ to search for completions (rlcompleter.py,
global_matches()):

for nspace in [builtins.__dict__, self.namespace]:
...

This behaviour may sometimes be unwanted. It would be nice to have an
option, which when set would tell completer to only use provided dictionary.

The attached patch fixes this issue and provides some tests.

The report says “This behaviour may sometimes be unwanted. It would be nice to have an option”, so I’m requalifying as a RFE and adjusting versions.

The patch changes behavior (search order was builtins, self.namespace and is now reversed), is this wanted?

The patch also needs to update the doc.

Thanks!

Yes, it is. I think the user would expect that kind of behaviour.

The attached patch updates the Doc.

Looks good to me.  I wrote one comment on the doc patch review.

Updated with tip, and merged with documentation.

I would make the argument keyword-only.
Changing the logic to avoid eval() might be OK, but IIUC is not related to this issue, and it should be done separately.
The markup in the doc could be better (`...` should be ``...`` or a more specific directive that generates a link).  A versionchanged should be added as well.

Updated. Note that removing `eval` is necessary for the new logic of the function.

This issue is not newcomer friendly, I remove the easy keyword.