tests/test-custom-filters.t

context: avoid breaking already fixed self._status at ctx.status()

Before this patch, "status()" on "workingcommitctx" with "always
match" object causes breaking "self._status" in
"workingctx._buildstatus()", because "workingctx._buildstatus()"
caches the result of "dirstate.status()" into "self._status" for
efficiency, even though it should be fixed at construction for
committing.

For example, template function "diff()" without any patterns in
"committemplate" implies "status()" on "workingcommitctx" with "always
match" object, via "basectx.diff()" and "patch.diff()".

Then, broken "self._status" causes committing unexpected files.

To avoid breaking already fixed "self._status" at "ctx.status()", this
patch overrides "_buildstatus" in "workingcommitctx".

This patch doesn't write out the result of template function "diff()"
in "committemplate" in "test-commit.t", because matching against files
to be committed still has an issue fixed in subsequent patch.

  $ hg init

  $ cat > .hg/hgrc <<EOF
  > [extensions]
  > prefixfilter = prefix.py
  > [encode]
  > *.txt = stripprefix: Copyright 2046, The Masters
  > [decode]
  > *.txt = insertprefix: Copyright 2046, The Masters
  > EOF

  $ cat > prefix.py <<EOF
  > from mercurial import util
  > def stripprefix(s, cmd, filename, **kwargs):
  >     header = '%s\n' % cmd
  >     if s[:len(header)] != header:
  >         raise util.Abort('missing header "%s" in %s' % (cmd, filename))
  >     return s[len(header):]
  > def insertprefix(s, cmd):
  >     return '%s\n%s' % (cmd, s)
  > def reposetup(ui, repo):
  >     repo.adddatafilter('stripprefix:', stripprefix)
  >     repo.adddatafilter('insertprefix:', insertprefix)
  > EOF

  $ cat > .hgignore <<EOF
  > .hgignore
  > prefix.py
  > prefix.pyc
  > EOF

  $ cat > stuff.txt <<EOF
  > Copyright 2046, The Masters
  > Some stuff to ponder very carefully.
  > EOF
  $ hg add stuff.txt
  $ hg ci -m stuff

Repository data:

  $ hg cat stuff.txt
  Some stuff to ponder very carefully.

Fresh checkout:

  $ rm stuff.txt
  $ hg up -C
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat stuff.txt
  Copyright 2046, The Masters
  Some stuff to ponder very carefully.
  $ echo "Very very carefully." >> stuff.txt
  $ hg stat
  M stuff.txt

  $ echo "Unauthorized material subject to destruction." > morestuff.txt

Problem encoding:

  $ hg add morestuff.txt
  $ hg ci -m morestuff
  abort: missing header "Copyright 2046, The Masters" in morestuff.txt
  [255]
  $ hg stat
  M stuff.txt
  A morestuff.txt