templatekw: compare target context and its parent exactly (issue4690) Before this patch, template keywords `{file_mods}`, `{file_adds}` and `{file_dels}` use values gotten by `repo.status(ctx.p1().node(), ctx.node())`. But this doesn't work as expected if `ctx` is `memctx` or `workingcommitctx`. Typical case of templating with these contexts is customization of the text shown in the commit message editor by `[committemplate]` configuration. In this case, `ctx.node()` returns None and it causes comparison between `ctx.p1()` and `workingctx`. `workingctx` lists up all changed files in the working directory even at selective committing. BTW, `{files}` uses `ctx.files()` and it works as expected. To compare target context and its parent exactly, this patch passes `ctx.p1()` and `ctx` without `node()`-nize. This avoids unexpected comparison with `workingctx`. This patch uses a little redundant template configurations in `test-commit.t`, but they are needed to avoid regression around problems fixed by a4958cdb2202 and 1e6fb8db666e: accessing on `ctx` may break `ctx._status` field.

  $ HGENCODING=utf-8
  $ export HGENCODING

  $ try() {
  >   hg debugrevspec --debug $@
  > }

  $ log() {
  >   hg log --template '{rev}\n' -r "$1"
  > }

  $ hg init repo
  $ cd repo

  $ try 'p1()'
  (func
    ('symbol', 'p1')
    None)
  * set:
  <baseset []>
  $ try 'p2()'
  (func
    ('symbol', 'p2')
    None)
  * set:
  <baseset []>
  $ try 'parents()'
  (func
    ('symbol', 'parents')
    None)
  * set:
  <baseset+ []>

null revision
  $ log 'p1()'
  $ log 'p2()'
  $ log 'parents()'

working dir with a single parent
  $ echo a > a
  $ hg ci -Aqm0
  $ log 'p1()'
  0
  $ log 'tag() and p1()'
  $ log 'p2()'
  $ log 'parents()'
  0
  $ log 'tag() and parents()'

merge in progress
  $ echo b > b
  $ hg ci -Aqm1
  $ hg up -q 0
  $ echo c > c
  $ hg ci -Aqm2
  $ hg merge -q
  $ log 'p1()'
  2
  $ log 'p2()'
  1
  $ log 'tag() and p2()'
  $ log 'parents()'
  1
  2

  $ cd ..