copies: rewrite copy detection for non-merge users
The existing copy detection API was designed with merge in mind and
was ill-suited for doing status/diff. The new pathcopies
implementation gives more accurate, easier to use results for
comparing two revisions, and is much simpler to understand.
Test notes:
- test-mv-cp-st.t results finds more renames in the reverse direction now
- test-mq-merge.t was always wrong and duplicated a copy in diff that
was already present in one of the parent revisions
Environement setup for MQ
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init
$ hg qinit
Should fail if no patches applied
$ hg qrefresh
no patches applied
[1]
$ hg qrefresh -e
no patches applied
[1]
$ hg qnew -m "First commit message" first-patch
$ echo aaaa > file
$ hg add file
$ hg qrefresh
Should display 'First commit message'
$ hg log -l1 --template "{desc}\n"
First commit message
Testing changing message with -m
$ echo bbbb > file
$ hg qrefresh -m "Second commit message"
Should display 'Second commit message'
$ hg log -l1 --template "{desc}\n"
Second commit message
Testing changing message with -l
$ echo "Third commit message" > logfile
$ echo " This is the 3rd log message" >> logfile
$ echo bbbb > file
$ hg qrefresh -l logfile
Should display 'Third commit message\\\n This is the 3rd log message'
$ hg log -l1 --template "{desc}\n"
Third commit message
This is the 3rd log message
Testing changing message with -l-
$ hg qnew -m "First commit message" second-patch
$ echo aaaa > file2
$ hg add file2
$ echo bbbb > file2
$ (echo "Fifth commit message"; echo " This is the 5th log message") | hg qrefresh -l-
Should display 'Fifth commit message\\\n This is the 5th log message'
$ hg log -l1 --template "{desc}\n"
Fifth commit message
This is the 5th log message