backout: improve confusing 'cannot backout change on a different branch' abort These days 'branch' usually refer to a named branch. Instead, abort with 'cannot backout change that not is an ancestor'.

config: set a 'source' in most cases where config don't come from file but code Some extensions set configuration settings that showed up in 'hg showconfig --debug' with 'none' as source. That was confusing. Instead, they will now tell which extension they come from. This change tries to be consistent and specify a source everywhere - also where it perhaps is less relevant.

config: don't set source when no source is specified - don't overwrite with '' This prevents ui.fixconfig from overwriting the source of paths and it will thus show up in showconfig --debug.

config: give a useful hint of source for the most common command line settings 'hg showconfig --debug' will instead of: none: ui.verbose=False give the better hint: --verbose: ui.verbose=False