view tests/test-casefolding.t @ 42222:57203e0210f8

copies: calculate mergecopies() based on pathcopies()

When copies are stored in changesets, we need a changeset-centric
version of mergecopies() just like we have a changeset-centric version
of pathcopies(). I think the natural way of thinking about
mergecopies() is in terms of pathcopies() from the base to each of the
commits. So if we can rewrite mergecopies() based on two such
pathcopies() calls, we'll get the changeset-centric version for
free. That's what this patch does.

A nice bonus is that it ends up being a lot simpler. mergecopies() has
accumulated a lot of technical debt over time. One good example is the
code for dealing with grafts (the "partial/incomplete/dirty"
stuff). Since pathcopies() already deals with backwards renames and
ping-pong renames, we get that for free.

I've run tests with hard-coded debug logging for "fullcopy" and while
I haven't looked at every difference it produces, all the ones I have
looked at seemed reasonable to me. I'm a little surprised that no more
tests fail when run with '--extra-config-opt
experimental.copies.read-from=compatibility' compared to before this
patch. This patch also fixes the broken cases in test-annotate.t and
test-fastannotate.t. It also enables the part of test-copies.t that
was previously disabled exactly because mergecopies() needed to get a
changeset-centric version.

One drawback of the rewritten code is that we may now make
remotefilelog prefetch more files. We used to prefetch files that were
unique to either side of the merge compared to the other. We now
prefetch files that are unique to either side of the merge compared to
the base. This means that if you added the same file to each side, we
would not prefetch it before, but we would now. Such cases are
probably quite rare, but one likely scenario where they happen is when
moving from a commit to its successor (or the other way around). The
user will probably already have the files in the cache in such cases,
so it's probably not a big deal.

Some timings for calculating mergecopies between two revisions
(revisions shown on each line, all using the common ancestor as base):

In the hg repo:
4.8 4.9: 0.21s -> 0.21s
4.0 4.8: 0.35s -> 0.63s

In and old copy of the mozilla-unified repo:
FIREFOX_BETA_60_BASE^ FIREFOX_BETA_60_BASE: 0.82s -> 0.82s
FIREFOX_NIGHTLY_59_END FIREFOX_BETA_60_BASE: 2.5s -> 2.6s
FIREFOX_BETA_59_END FIREFOX_BETA_60_BASE: 3.9s -> 4.1s
FIREFOX_AURORA_50_BASE FIREFOX_BETA_60_BASE: 31s -> 33s

So it's measurably slower in most cases. The most significant
difference is in the hg repo between revisions 4.0 and 4.8. In that
case it seems to come from the fact that pathcopies() uses
fctx.isintroducedafter() (in _tracefile), while the old mergecopies()
used fctx.linkrev() (in _checkcopies()). That results in a single call
to filectx._adjustlinkrev(), which is responsible for the entire
difference in time (in my repo). So we pay a performance penalty but
we get more correct code (see change in
test-mv-cp-st-diff.t). Deleting the "== f.filenode()" in _tracefile()
recovers the lost performance in the hg repo.

There were are few other optimizations in _checkcopies() that I could
not measure any impact from. One was from the "seen" set. Another was
from a "continue" when the file was not in the destination manifest
(corresponding to "am" in _tracefile).

Also note that merge copies are not calculated when updating with a
clean working copy, which is probably the most common case. I
therefore think the much simpler code is worth the slowdown.

Differential Revision: https://phab.mercurial-scm.org/D6255

#require icasefs

  $ hg debugfs | grep 'case-sensitive:'
  case-sensitive: no

test file addition with bad case

  $ hg init repo1
  $ cd repo1
  $ echo a > a
  $ hg add A
  $ hg st
  A a
  $ hg ci -m adda
  $ hg manifest
  a
  $ cd ..

test case collision on rename (issue750)

  $ hg init repo2
  $ cd repo2
  $ echo a > a
  $ hg --debug ci -Am adda
  adding a
  committing files:
  a
  committing manifest
  committing changelog
  updating the branch cache
  committed changeset 0:07f4944404050f47db2e5c5071e0e84e7a27bba9

Case-changing renames should work:

  $ hg mv a A
  $ hg mv A a
  $ hg st

addremove after case-changing rename has no effect (issue4590)

  $ hg mv a A
  $ hg addremove
  recording removal of a as rename to A (100% similar)
  $ hg revert --all
  forgetting A
  undeleting a

test changing case of path components

  $ mkdir D
  $ echo b > D/b
  $ hg ci -Am addb D/b
  $ hg mv D/b d/b
  D/b: not overwriting - file already committed
  ('hg rename --force' to replace the file by recording a rename)
  [1]
  $ hg mv D/b d/c
  $ hg st
  A D/c
  R D/b
  $ mv D temp
  $ mv temp d
  $ hg st
  A D/c
  R D/b
  $ hg revert -aq
  $ rm d/c
  $ echo c > D/c
  $ hg add D/c
  $ hg st
  A D/c
  $ hg ci -m addc D/c
  $ hg mv d/b d/e
  $ hg st
  A D/e
  R D/b
  $ hg revert -aq
  $ rm d/e
  $ hg mv d/b D/B
  $ hg st
  A D/B
  R D/b
  $ cd ..

test case collision between revisions (issue912)

  $ hg init repo3
  $ cd repo3
  $ echo a > a
  $ hg ci -Am adda
  adding a
  $ hg rm a
  $ hg ci -Am removea
  $ echo A > A

on linux hfs keeps the old case stored, force it

  $ mv a aa
  $ mv aa A
  $ hg ci -Am addA
  adding A

used to fail under case insensitive fs

  $ hg up -C 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg up -C
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

no clobbering of untracked files with wrong casing

  $ hg up -r null
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo gold > a
  $ hg up
  A: untracked file differs
  abort: untracked files in working directory differ from files in requested revision
  [255]
  $ cat a
  gold
  $ rm a

test that normal file in different case on target context is not
unlinked by largefiles extension.

  $ cat >> .hg/hgrc <<EOF
  > [extensions]
  > largefiles=
  > EOF
  $ hg update -q -C 1
  $ hg status -A
  $ echo 'A as largefiles' > A
  $ hg add --large A
  $ hg commit -m '#3'
  created new head
  $ hg manifest -r 3
  .hglf/A
  $ hg manifest -r 0
  a
  $ hg update -q -C 0
  $ hg status -A
  C a
  $ hg update -q -C 3
  $ hg update -q 0

  $ hg up -C -r 2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg mv A a
  $ hg diff -g > rename.diff
  $ hg ci -m 'A -> a'
  $ hg up -q '.^'
  $ hg import rename.diff -m "import rename A -> a"
  applying rename.diff
  $ hg st
  ? rename.diff
  $ hg files
  a
  $ find * | sort
  a
  rename.diff

  $ rm rename.diff

  $ cd ..

issue 3342: file in nested directory causes unexpected abort

  $ hg init issue3342
  $ cd issue3342

  $ mkdir -p a/B/c/D
  $ echo e > a/B/c/D/e
  $ hg add a/B/c/D/e
  $ hg ci -m 'add e'

issue 4481: revert across case only renames
  $ hg mv a/B/c/D/e a/B/c/d/E
  $ hg ci -m "uppercase E"
  $ echo 'foo' > a/B/c/D/E
  $ hg ci -m 'e content change'
  $ hg revert --all -r 0
  removing a/B/c/D/E
  adding a/B/c/D/e
  $ find * | sort
  a
  a/B
  a/B/c
  a/B/c/D
  a/B/c/D/e
  a/B/c/D/e.orig

  $ cd ..

issue 3340: mq does not handle case changes correctly

in addition to reported case, 'hg qrefresh' is also tested against
case changes.

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "mq=" >> $HGRCPATH

  $ hg init issue3340
  $ cd issue3340

  $ echo a > mIxEdCaSe
  $ hg add mIxEdCaSe
  $ hg commit -m '#0'
  $ hg rename mIxEdCaSe tmp
  $ hg rename tmp MiXeDcAsE
  $ hg status -A
  A MiXeDcAsE
    mIxEdCaSe
  R mIxEdCaSe
  $ hg qnew changecase
  $ hg status -A
  C MiXeDcAsE

  $ hg qpop -a
  popping changecase
  patch queue now empty
  $ hg qnew refresh-casechange
  $ hg status -A
  C mIxEdCaSe
  $ hg rename mIxEdCaSe tmp
  $ hg rename tmp MiXeDcAsE
  $ hg status -A
  A MiXeDcAsE
    mIxEdCaSe
  R mIxEdCaSe
  $ hg qrefresh
  $ hg status -A
  C MiXeDcAsE

  $ hg qpop -a
  popping refresh-casechange
  patch queue now empty
  $ hg qnew refresh-pattern
  $ hg status
  $ echo A > A
  $ hg add
  adding A
  $ hg qrefresh a # issue 3271, qrefresh with file handled case wrong
  $ hg status # empty status means the qrefresh worked

#if osx

We assume anyone running the tests on a case-insensitive volume on OS
X will be using HFS+. If that's not true, this test will fail.

  $ rm A
  >>> open(u'a\u200c'.encode('utf-8'), 'w').write('unicode is fun') and None
  $ hg status
  M A

#endif

  $ cd ..