view tests/test-fix-topology.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

A script that implements uppercasing all letters in a file.

  $ UPPERCASEPY="$TESTTMP/uppercase.py"
  $ cat > $UPPERCASEPY <<EOF
  > import sys
  > from mercurial.utils.procutil import setbinary
  > setbinary(sys.stdin)
  > setbinary(sys.stdout)
  > sys.stdout.write(sys.stdin.read().upper())
  > EOF
  $ TESTLINES="foo\nbar\nbaz\n"
  $ printf $TESTLINES | "$PYTHON" $UPPERCASEPY
  FOO
  BAR
  BAZ

Tests for the fix extension's behavior around non-trivial history topologies.
Looks for correct incremental fixing and reproduction of parent/child
relationships. We indicate fixed file content by uppercasing it.

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > fix =
  > [fix]
  > uppercase-whole-file:command="$PYTHON" $UPPERCASEPY
  > uppercase-whole-file:pattern=set:**
  > EOF

This tests the only behavior that should really be affected by obsolescence, so
we'll test it with evolution off and on. This only changes the revision
numbers, if all is well.

#testcases obsstore-off obsstore-on
#if obsstore-on
  $ cat >> $HGRCPATH <<EOF
  > [experimental]
  > evolution.createmarkers=True
  > evolution.allowunstable=True
  > EOF
#endif

Setting up the test topology. Scroll down to see the graph produced. We make it
clear which files were modified in each revision. It's enough to test at the
file granularity, because that demonstrates which baserevs were diffed against.
The computation of changed lines is orthogonal and tested separately.

  $ hg init repo
  $ cd repo

  $ printf "aaaa\n" > a
  $ hg commit -Am "change A"
  adding a
  $ printf "bbbb\n" > b
  $ hg commit -Am "change B"
  adding b
  $ printf "cccc\n" > c
  $ hg commit -Am "change C"
  adding c
  $ hg checkout 0
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ printf "dddd\n" > d
  $ hg commit -Am "change D"
  adding d
  created new head
  $ hg merge -r 2
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ printf "eeee\n" > e
  $ hg commit -Am "change E"
  adding e
  $ hg checkout 0
  0 files updated, 0 files merged, 4 files removed, 0 files unresolved
  $ printf "ffff\n" > f
  $ hg commit -Am "change F"
  adding f
  created new head
  $ hg checkout 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ printf "gggg\n" > g
  $ hg commit -Am "change G"
  adding g
  created new head
  $ hg merge -r 5
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ printf "hhhh\n" > h
  $ hg commit -Am "change H"
  adding h
  $ hg merge -r 4
  4 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ printf "iiii\n" > i
  $ hg commit -Am "change I"
  adding i
  $ hg checkout 2
  0 files updated, 0 files merged, 6 files removed, 0 files unresolved
  $ printf "jjjj\n" > j
  $ hg commit -Am "change J"
  adding j
  created new head
  $ hg checkout 7
  3 files updated, 0 files merged, 3 files removed, 0 files unresolved
  $ printf "kkkk\n" > k
  $ hg add
  adding k

  $ hg log --graph --template '{rev} {desc}\n'
  o  9 change J
  |
  | o    8 change I
  | |\
  | | @    7 change H
  | | |\
  | | | o  6 change G
  | | | |
  | | o |  5 change F
  | | |/
  | o |  4 change E
  |/| |
  | o |  3 change D
  | |/
  o |  2 change C
  | |
  o |  1 change B
  |/
  o  0 change A
  

Fix all but the root revision and its four children.

#if obsstore-on
  $ hg fix -r '2|4|7|8|9' --working-dir
#else
  $ hg fix -r '2|4|7|8|9' --working-dir
  saved backup bundle to * (glob)
#endif

The five revisions remain, but the other revisions were fixed and replaced. All
parent pointers have been accurately set to reproduce the previous topology
(though it is rendered in a slightly different order now).

#if obsstore-on
  $ hg log --graph --template '{rev} {desc}\n'
  o  14 change J
  |
  | o    13 change I
  | |\
  | | @    12 change H
  | | |\
  | o | |  11 change E
  |/| | |
  o | | |  10 change C
  | | | |
  | | | o  6 change G
  | | | |
  | | o |  5 change F
  | | |/
  | o /  3 change D
  | |/
  o /  1 change B
  |/
  o  0 change A
  
  $ C=10
  $ E=11
  $ H=12
  $ I=13
  $ J=14
#else
  $ hg log --graph --template '{rev} {desc}\n'
  o  9 change J
  |
  | o    8 change I
  | |\
  | | @    7 change H
  | | |\
  | o | |  6 change E
  |/| | |
  o | | |  5 change C
  | | | |
  | | | o  4 change G
  | | | |
  | | o |  3 change F
  | | |/
  | o /  2 change D
  | |/
  o /  1 change B
  |/
  o  0 change A
  
  $ C=5
  $ E=6
  $ H=7
  $ I=8
  $ J=9
#endif

Change C is a root of the set being fixed, so all we fix is what has changed
since its parent. That parent, change B, is its baserev.

  $ hg cat -r $C 'set:**'
  aaaa
  bbbb
  CCCC

Change E is a merge with only one parent being fixed. Its baserevs are the
unfixed parent plus the baserevs of the other parent. This evaluates to changes
B and D. We now have to decide what it means to incrementally fix a merge
commit. We choose to fix anything that has changed versus any baserev. Only the
undisturbed content of the common ancestor, change A, is unfixed.

  $ hg cat -r $E 'set:**'
  aaaa
  BBBB
  CCCC
  DDDD
  EEEE

Change H is a merge with neither parent being fixed. This is essentially
equivalent to the previous case because there is still only one baserev for
each parent of the merge.

  $ hg cat -r $H 'set:**'
  aaaa
  FFFF
  GGGG
  HHHH

Change I is a merge that has four baserevs; two from each parent. We handle
multiple baserevs in the same way regardless of how many came from each parent.
So, fixing change H will fix any files that were not exactly the same in each
baserev.

  $ hg cat -r $I 'set:**'
  aaaa
  BBBB
  CCCC
  DDDD
  EEEE
  FFFF
  GGGG
  HHHH
  IIII

Change J is a simple case with one baserev, but its baserev is not its parent,
change C. Its baserev is its grandparent, change B.

  $ hg cat -r $J 'set:**'
  aaaa
  bbbb
  CCCC
  JJJJ

The working copy was dirty, so it is treated much like a revision. The baserevs
for the working copy are inherited from its parent, change H, because it is
also being fixed.

  $ cat *
  aaaa
  FFFF
  GGGG
  HHHH
  KKKK

Change A was never a baserev because none of its children were to be fixed.

  $ cd ..

The --all flag should fix anything that wouldn't cause a problem if you fixed
it, including the working copy. Obsolete revisions are not fixed because that
could cause divergence. Public revisions would cause an abort because they are
immutable. We can fix orphans because their successors are still just orphans
of the original obsolete parent. When obsolesence is off, we're just fixing and
replacing anything that isn't public.

  $ hg init fixall
  $ cd fixall

#if obsstore-on
  $ printf "one\n" > foo.whole
  $ hg commit -Aqm "first"
  $ hg phase --public
  $ hg tag --local root
  $ printf "two\n" > foo.whole
  $ hg commit -m "second"
  $ printf "three\n" > foo.whole
  $ hg commit -m "third" --secret
  $ hg tag --local secret
  $ hg checkout root
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ printf "four\n" > foo.whole
  $ hg commit -m "fourth"
  created new head
  $ printf "five\n" > foo.whole
  $ hg commit -m "fifth"
  $ hg tag --local replaced
  $ printf "six\n" > foo.whole
  $ hg commit -m "sixth"
  $ hg checkout replaced
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ printf "seven\n" > foo.whole
  $ hg commit --amend
  1 new orphan changesets
  $ hg checkout secret
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ printf "uncommitted\n" > foo.whole

  $ hg log --graph --template '{rev} {desc} {phase}\n'
  o  6 fifth draft
  |
  | *  5 sixth draft
  | |
  | x  4 fifth draft
  |/
  o  3 fourth draft
  |
  | @  2 third secret
  | |
  | o  1 second draft
  |/
  o  0 first public
  

  $ hg fix --all

  $ hg log --graph --template '{rev} {desc}\n' -r 'sort(all(), topo)' --hidden
  o  11 fifth
  |
  o  9 fourth
  |
  | @  8 third
  | |
  | o  7 second
  |/
  | *  10 sixth
  | |
  | | x  5 sixth
  | |/
  | x  4 fifth
  | |
  | | x  6 fifth
  | |/
  | x  3 fourth
  |/
  | x  2 third
  | |
  | x  1 second
  |/
  o  0 first
  

  $ hg cat -r 7 foo.whole
  TWO
  $ hg cat -r 8 foo.whole
  THREE
  $ hg cat -r 9 foo.whole
  FOUR
  $ hg cat -r 10 foo.whole
  SIX
  $ hg cat -r 11 foo.whole
  SEVEN
  $ cat foo.whole
  UNCOMMITTED
#else
  $ printf "one\n" > foo.whole
  $ hg commit -Aqm "first"
  $ hg phase --public
  $ hg tag --local root
  $ printf "two\n" > foo.whole
  $ hg commit -m "second"
  $ printf "three\n" > foo.whole
  $ hg commit -m "third" --secret
  $ hg tag --local secret
  $ hg checkout root
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ printf "four\n" > foo.whole
  $ hg commit -m "fourth"
  created new head
  $ printf "uncommitted\n" > foo.whole

  $ hg log --graph --template '{rev} {desc} {phase}\n'
  @  3 fourth draft
  |
  | o  2 third secret
  | |
  | o  1 second draft
  |/
  o  0 first public
  

  $ hg fix --all
  saved backup bundle to * (glob)

  $ hg log --graph --template '{rev} {desc} {phase}\n'
  @  3 fourth draft
  |
  | o  2 third secret
  | |
  | o  1 second draft
  |/
  o  0 first public
  
  $ hg cat -r 0 foo.whole
  one
  $ hg cat -r 1 foo.whole
  TWO
  $ hg cat -r 2 foo.whole
  THREE
  $ hg cat -r 3 foo.whole
  FOUR
  $ cat foo.whole
  UNCOMMITTED
#endif

  $ cd ..