annotate tests/test-manifest.t @ 42619:20d0e59be79b

tests: show the files fields of changelogs for many merges

I don't think there's coverage for many of the subtle cases, and I
found it hard to understand what the code is doing by reading it.  The
test takes 40s to run on a laptop, or 9s with --chg.

I have yet to find a description of what the files field is supposed
to be for merges. I thought it could be one of:
1. the files added/modified/removed relative to p1 (wouldn't seem
  useful, but `hg diff -c -r mergerev` has this behavior)
2. the files with filelog nodes not in either parent (i.e., what is
needed to create a bundle out of a commit)
3. the files added/removed/modified files by merge itself [1]

It's clearly not 1, because file contents merges are symmetric. It's
clearly not 2 because removed files and exec bit changes are
listed. It's also not 3 but I think it's intended to be 3 and the
differences are bugs.

Assuming 3, the test shows that, for merges, the list of files both
overapproximates and underapproximates. All the cases involve file
changes not in the filelog but in the manifest (existence of file
at revision, exec bit and file vs symlink).

I didn't look at all underapproximations, but they looked minor. The
two overapproximations are problematic though because they both cause
potentially long lists of files when merging cleanly.


[1] even what it means for the merge commit itself to change a file is
not completely trivial. A file in the merge being the same as in one
of the parent is too lax as it would consider that merges change
nothing when they revert all the changes done on one side. The
criteria used in the test and in the next commit for "merge didn't
touch a file" is:
- the parents and the merge all have the same file
- or, one parent didn't touch the file and the other parent contains
  the same file as the merge

Differential Revision: https://phab.mercurial-scm.org/D6612

Source bundle was generated with the following script:

# hg init
# echo a > a
# ln -s a l
# hg ci -Ama -d'0 0'
# mkdir b
# echo a > b/a
# chmod +x b/a
# hg ci -Amb -d'1 0'

  $ hg init
  $ hg unbundle "$TESTDIR/bundles/test-manifest.hg"
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 3 changes to 3 files
  new changesets b73562a03cfe:5bdc995175ba (2 drafts)
  (run 'hg update' to get a working copy)

The next call is expected to return nothing:

  $ hg manifest

  $ hg co
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg manifest
  a
  b/a
  l

  $ hg files -vr .
           2   a
           2 x b/a
           1 l l
  $ hg files -r . -X b
  a
  l
  $ hg files -T '{path} {size} {flags}\n'
  a 2 
  b/a 2 x
  l 1 l
  $ hg files -T '{path} {node|shortest}\n' -r.
  a 5bdc
  b/a 5bdc
  l 5bdc

  $ hg manifest -v
  644   a
  755 * b/a
  644 @ l
  $ hg manifest -T '{path} {rev}\n'
  a 1
  b/a 1
  l 1

  $ hg manifest --debug
  b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 644   a
  b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 755 * b/a
  047b75c6d7a3ef6a2243bd0e99f94f6ea6683597 644 @ l

  $ hg manifest -r 0
  a
  l

  $ hg manifest -r 1
  a
  b/a
  l

  $ hg manifest -r tip
  a
  b/a
  l

  $ hg manifest tip
  a
  b/a
  l

  $ hg manifest --all
  a
  b/a
  l

The next two calls are expected to abort:

  $ hg manifest -r 2
  abort: unknown revision '2'!
  [255]

  $ hg manifest -r tip tip
  abort: please specify just one revision
  [255]

Testing the manifest full text cache utility
--------------------------------------------

Reminder of the manifest log content

  $ hg log --debug | grep 'manifest:'
  manifest:    1:1e01206b1d2f72bd55f2a33fa8ccad74144825b7
  manifest:    0:fce2a30dedad1eef4da95ca1dc0004157aa527cf

Showing the content of the caches after the above operations

  $ hg debugmanifestfulltextcache
  cache contains 1 manifest entries, in order of most to least recent:
  id: 1e01206b1d2f72bd55f2a33fa8ccad74144825b7, size 133 bytes
  total cache data size 157 bytes, on-disk 157 bytes

(Clearing the cache in case of any content)

  $ hg debugmanifestfulltextcache --clear

Adding a new persistent entry in the cache

  $ hg debugmanifestfulltextcache --add 1e01206b1d2f72bd55f2a33fa8ccad74144825b7

  $ hg debugmanifestfulltextcache
  cache contains 1 manifest entries, in order of most to least recent:
  id: 1e01206b1d2f72bd55f2a33fa8ccad74144825b7, size 133 bytes
  total cache data size 157 bytes, on-disk 157 bytes

Check we don't duplicated entry (added from the debug command)

  $ hg debugmanifestfulltextcache --add 1e01206b1d2f72bd55f2a33fa8ccad74144825b7
  $ hg debugmanifestfulltextcache
  cache contains 1 manifest entries, in order of most to least recent:
  id: 1e01206b1d2f72bd55f2a33fa8ccad74144825b7, size 133 bytes
  total cache data size 157 bytes, on-disk 157 bytes

Adding a second entry

  $ hg debugmanifestfulltextcache --add fce2a30dedad1eef4da95ca1dc0004157aa527cf
  $ hg debugmanifestfulltextcache
  cache contains 2 manifest entries, in order of most to least recent:
  id: fce2a30dedad1eef4da95ca1dc0004157aa527cf, size 87 bytes
  id: 1e01206b1d2f72bd55f2a33fa8ccad74144825b7, size 133 bytes
  total cache data size 268 bytes, on-disk 268 bytes

Accessing the initial entry again, refresh their order

  $ hg debugmanifestfulltextcache --add 1e01206b1d2f72bd55f2a33fa8ccad74144825b7
  $ hg debugmanifestfulltextcache
  cache contains 2 manifest entries, in order of most to least recent:
  id: 1e01206b1d2f72bd55f2a33fa8ccad74144825b7, size 133 bytes
  id: fce2a30dedad1eef4da95ca1dc0004157aa527cf, size 87 bytes
  total cache data size 268 bytes, on-disk 268 bytes

Check cache clearing

  $ hg debugmanifestfulltextcache --clear
  $ hg debugmanifestfulltextcache
  cache empty

Check adding multiple entry in one go:

  $ hg debugmanifestfulltextcache --add fce2a30dedad1eef4da95ca1dc0004157aa527cf  --add 1e01206b1d2f72bd55f2a33fa8ccad74144825b7
  $ hg debugmanifestfulltextcache
  cache contains 2 manifest entries, in order of most to least recent:
  id: 1e01206b1d2f72bd55f2a33fa8ccad74144825b7, size 133 bytes
  id: fce2a30dedad1eef4da95ca1dc0004157aa527cf, size 87 bytes
  total cache data size 268 bytes, on-disk 268 bytes
  $ hg debugmanifestfulltextcache --clear

Test caching behavior on actual operation
-----------------------------------------

Make sure we start empty

  $ hg debugmanifestfulltextcache
  cache empty

Commit should have the new node cached:

  $ echo a >> b/a
  $ hg commit -m 'foo'
  $ hg debugmanifestfulltextcache
  cache contains 2 manifest entries, in order of most to least recent:
  id: 26b8653b67af8c1a0a0317c4ee8dac50a41fdb65, size 133 bytes
  id: 1e01206b1d2f72bd55f2a33fa8ccad74144825b7, size 133 bytes
  total cache data size 314 bytes, on-disk 314 bytes
  $ hg log -r 'ancestors(., 1)' --debug | grep 'manifest:'
  manifest:    1:1e01206b1d2f72bd55f2a33fa8ccad74144825b7
  manifest:    2:26b8653b67af8c1a0a0317c4ee8dac50a41fdb65

hg update should warm the cache too

(force dirstate check to avoid flackiness in manifest order)
  $ hg debugrebuilddirstate

  $ hg update 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg debugmanifestfulltextcache
  cache contains 3 manifest entries, in order of most to least recent:
  id: fce2a30dedad1eef4da95ca1dc0004157aa527cf, size 87 bytes
  id: 26b8653b67af8c1a0a0317c4ee8dac50a41fdb65, size 133 bytes
  id: 1e01206b1d2f72bd55f2a33fa8ccad74144825b7, size 133 bytes
  total cache data size 425 bytes, on-disk 425 bytes
  $ hg log -r '0' --debug | grep 'manifest:'
  manifest:    0:fce2a30dedad1eef4da95ca1dc0004157aa527cf

Test file removal (especially with pure).  The tests are crafted such that there
will be contiguous spans of existing entries to ensure that is handled properly.
(In this case, a.txt, aa.txt and c.txt, cc.txt, and ccc.txt)

  $ cat > $TESTTMP/manifest.py <<EOF
  > from mercurial import (
  >     extensions,
  >     manifest,
  > )
  > def extsetup(ui):
  >     manifest.FASTDELTA_TEXTDIFF_THRESHOLD = 0
  > EOF
  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > manifest = $TESTTMP/manifest.py
  > EOF

Pure removes should actually remove all dropped entries

  $ hg init repo
  $ cd repo
  $ echo a > a.txt
  $ echo aa > aa.txt
  $ echo b > b.txt
  $ echo c > c.txt
  $ echo c > cc.txt
  $ echo c > ccc.txt
  $ echo b > d.txt
  $ echo c > e.txt
  $ hg ci -Aqm 'a-e'

  $ hg rm b.txt d.txt
  $ hg ci -m 'remove b and d'

  $ hg debugdata -m 1
  a.txt\x00b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 (esc)
  aa.txt\x00a4bdc161c8fbb523c9a60409603f8710ff49a571 (esc)
  c.txt\x00149da44f2a4e14f488b7bd4157945a9837408c00 (esc)
  cc.txt\x00149da44f2a4e14f488b7bd4157945a9837408c00 (esc)
  ccc.txt\x00149da44f2a4e14f488b7bd4157945a9837408c00 (esc)
  e.txt\x00149da44f2a4e14f488b7bd4157945a9837408c00 (esc)

  $ hg up -qC .

  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  checked 2 changesets with 8 changes to 8 files

  $ hg rollback -q --config ui.rollback=True
  $ hg rm b.txt d.txt
  $ echo bb > bb.txt

A mix of adds and removes should remove all dropped entries.

  $ hg ci -Aqm 'remove b and d; add bb'

  $ hg debugdata -m 1
  a.txt\x00b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 (esc)
  aa.txt\x00a4bdc161c8fbb523c9a60409603f8710ff49a571 (esc)
  bb.txt\x0004c6faf8a9fdd848a5304dfc1704749a374dff44 (esc)
  c.txt\x00149da44f2a4e14f488b7bd4157945a9837408c00 (esc)
  cc.txt\x00149da44f2a4e14f488b7bd4157945a9837408c00 (esc)
  ccc.txt\x00149da44f2a4e14f488b7bd4157945a9837408c00 (esc)
  e.txt\x00149da44f2a4e14f488b7bd4157945a9837408c00 (esc)

  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  checked 2 changesets with 9 changes to 9 files