dirstate-v2: add check of parent/child nodes being related when writing
This stems from a corruption seen in a private repository. We're not sure
of the source of the corruption, and it's very possible that we're seeing
compounded effects of multiple writes on a corrupted dirstate.
Adding this check is not expensive in itself and large writes of the dirstate
are not common.
This change does not catch this problem at the root node, the next one will.
Create a repo and add some commits
$ hg init mm
$ cd mm
$ echo "Test content" > testfile1
$ hg add testfile1
$ hg commit -m "First commit" -u "Proper <commit@m.c>"
$ echo "Test content 2" > testfile2
$ hg add testfile2
$ hg commit -m "Second commit" -u "Commit Name 2 <commit2@m.c>"
$ echo "Test content 3" > testfile3
$ hg add testfile3
$ hg commit -m "Third commit" -u "Commit Name 3 <commit3@m.c>"
$ echo "Test content 4" > testfile4
$ hg add testfile4
$ hg commit -m "Fourth commit" -u "Commit Name 4 <commit4@m.c>"
Add a .mailmap file with each possible entry type plus comments
$ cat > .mailmap << EOF
> # Comment shouldn't break anything
> <proper@m.c> <commit@m.c> # Should update email only
> Proper Name 2 <commit2@m.c> # Should update name only
> Proper Name 3 <proper@m.c> <commit3@m.c> # Should update name, email due to email
> Proper Name 4 <proper@m.c> Commit Name 4 <commit4@m.c> # Should update name, email due to name, email
> EOF
$ hg add .mailmap
$ hg commit -m "Add mailmap file" -u "Testuser <test123@m.c>"
Output of commits should be normal without filter
$ hg log -T "{author}\n" -r "all()"
Proper <commit@m.c>
Commit Name 2 <commit2@m.c>
Commit Name 3 <commit3@m.c>
Commit Name 4 <commit4@m.c>
Testuser <test123@m.c>
Output of commits with filter shows their mailmap values
$ hg log -T "{mailmap(author)}\n" -r "all()"
Proper <proper@m.c>
Proper Name 2 <commit2@m.c>
Proper Name 3 <proper@m.c>
Proper Name 4 <proper@m.c>
Testuser <test123@m.c>
Add new mailmap entry for testuser
$ cat >> .mailmap << EOF
> <newmmentry@m.c> <test123@m.c>
> EOF
Output of commits with filter shows their updated mailmap values
$ hg log -T "{mailmap(author)}\n" -r "all()"
Proper <proper@m.c>
Proper Name 2 <commit2@m.c>
Proper Name 3 <proper@m.c>
Proper Name 4 <proper@m.c>
Testuser <newmmentry@m.c>
A commit with improperly formatted user field should not break the filter
$ echo "some more test content" > testfile1
$ hg commit -m "Commit with improper user field" -u "Improper user"
$ hg log -T "{mailmap(author)}\n" -r "all()"
Proper <proper@m.c>
Proper Name 2 <commit2@m.c>
Proper Name 3 <proper@m.c>
Proper Name 4 <proper@m.c>
Testuser <newmmentry@m.c>
Improper user
No TypeError beacause of invalid input
$ hg log -T '{mailmap(termwidth)}\n' -r0
80