HG extension "record" for partial commits

[Rik]

jwe,

During Octconf 2018 we were talking about a methodology for doing partial
commits.  The use case is that one begins tackling a certain bug and makes
some code changes.  Along the way you notice a different bug, such as a
typo in the documentation of another function, which you also fix.  After
the code changes are complete you are ready to check in the changes for the
original bug, but the local repo contains modifications for both issues.

If the changes reside in different *files* then you can do 'hg ci
LIST_OF_BUG1_FILES' to check in the changes associated only with BUG1. 
However, if there are simultaneous changes in a single file then try 'hg
record'.  This will allow you to interactively choose, for each diff hunk,
which is recorded and which is not.

--Rik