registrar: raise a programming error on duplicated registering Previous, registering different object with the same name would silently overwrite the first value with the second one. We now detect the situation and raise an error. No extension in test or core had the issues.

py3kcompat: drop unused module Perhaps this was a predated attempt of Python 3 porting. Python 3.5 supports %-formatting of bytes.

strutil: drop module which no longer be used

convert: inline strutil.rfindall() This is the only place where strutil is used. I don't think it's worth to keep the strutil module, so inline it. Also, strutil.rfindall() appears to have off-by-one error. 'end = c - 1' is wrong because 'end' is exclusive.

convert: return commit objects for revisions in the revmap Source revision data that exists in the revmap are ignored when pulling data from Perforce as we consider them already imported. In case where the `convertcmd.convert` algorithm requests a commit object for such a revision we are creating it. This is usually the case for parent of the first imported revision.

convert: encapsulate commit data fetching and commit object creation Split fetching the `describe` form from Perforce and the commit object creation into two functions. This allows us to reuse the commit construction for revisions passed from a revmap.

convert: do not provide head revisions if we have no changests to import Don't set a head revision in cases where we have a revmap but no changesets to import, as convertcmd.convert() treats them as heads of to-imported revisions.

convert: allow passing in a revmap Implement `common.setrevmap` which is used to pass in a file with existing revision mappings. This functionality is used by `convertcmd.convert` if it exists and allows implementors such as the p4 converter to make use of an existing mapping. We are using the revmap to abort scanning and the repository for more information if we already have the revision. This means we are allowing incremental imports in cases where a revmap is provided.