History of a source line

[Eli Zaretskii]

Is there any bzr commands or plugins that can show all the revisions
that changed a certain source line?

Many times I need to do some forensic research to understand why some
code is written like it is.  With a large and old package such as
Emacs, the origins of some code fragments are lost in time.  It is
easy to see the last change with "bzr annotate" and "bzr diff -c", but
if you want to see beyond that, you need to grep ChangeLog files, look
for the revisions corresponding to the entries you _think_ may be
relevant, and that's a tedious and boring job.  And if you are unlucky
and the ChangeLog entry was not made at the time, it becomes an almost
impossible job, certainly an impractical one.

Does Bazaar offer any cure for this?

TIA