test-log: Add test for "hg log -pf" (issue647) To test f786fc4b8764 we analyze this repo: 0 | 1 | 2 | 3 | 4 a ------------> b \ b -> dir/b -------> e d We follow dir/b and expects rev 0, 1 and 2. A log following b will surprisingly report rev 0 and 1. That's because the content and the parents are the same in rev 1 and rev 3, and the revlog entry from rev 1 is thus reused in rev 3 even though the revlink is incorrect. Note that if we follow e then we will get all revs, including rev 3, because b gets added to the set of interesting filenames we are following through all revisions. That might be surprising, but that's (currently) how it is. Original test case by Joel Rosdahl <joel@rosdahl.net> Original test reviewed by Nicolas Dumazet <nicdumz@gmail.com>