view tests/test-import-eol.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

  $ cat > makepatch.py <<EOF
  > import sys
  > f = open(sys.argv[2], 'wb')
  > w = f.write
  > w(b'test message\n')
  > w(b'diff --git a/a b/a\n')
  > w(b'--- a/a\n')
  > w(b'+++ b/a\n')
  > w(b'@@ -1,5 +1,5 @@\n')
  > w(b' a\n')
  > w(b'-bbb\r\n')
  > w(b'+yyyy\r\n')
  > w(b' cc\r\n')
  > w({'empty:lf': b' \n',
  >    'empty:crlf': b' \r\n',
  >    'empty:stripped-lf': b'\n',
  >    'empty:stripped-crlf': b'\r\n'}[sys.argv[1]])
  > w(b' d\n')
  > w(b'-e\n')
  > w(b'\\\\ No newline at end of file\n')
  > w(b'+z\r\n')
  > w(b'\\\\ No newline at end of file\r\n')
  > EOF

  $ hg init repo
  $ cd repo
  $ echo '\.diff' > .hgignore


Test different --eol values

  $ "$PYTHON" -c 'open("a", "wb").write(b"a\nbbb\ncc\n\nd\ne")'
  $ hg ci -Am adda
  adding .hgignore
  adding a
  $ "$PYTHON" ../makepatch.py empty:lf eol.diff
  $ "$PYTHON" ../makepatch.py empty:crlf eol-empty-crlf.diff
  $ "$PYTHON" ../makepatch.py empty:stripped-lf eol-empty-stripped-lf.diff
  $ "$PYTHON" ../makepatch.py empty:stripped-crlf eol-empty-stripped-crlf.diff

invalid eol

  $ hg --config patch.eol='LFCR' import eol.diff
  applying eol.diff
  abort: unsupported line endings type: LFCR
  [255]
  $ hg revert -a


force LF

  $ hg --traceback --config patch.eol='LF' import eol.diff
  applying eol.diff
  $ hg id
  9e4ef7b3d4af tip
  $ cat a
  a
  yyyy
  cc
  
  d
  e (no-eol)
  $ hg st

 (test empty-line variants: all of them should generate the same revision)

  $ hg up -qC 0
  $ hg --config patch.eol='LF' import eol-empty-crlf.diff
  applying eol-empty-crlf.diff
  $ hg id
  9e4ef7b3d4af tip

  $ hg up -qC 0
  $ hg --config patch.eol='LF' import eol-empty-stripped-lf.diff
  applying eol-empty-stripped-lf.diff
  $ hg id
  9e4ef7b3d4af tip

  $ hg up -qC 0
  $ hg --config patch.eol='LF' import eol-empty-stripped-crlf.diff
  applying eol-empty-stripped-crlf.diff
  $ hg id
  9e4ef7b3d4af tip

force CRLF

  $ hg up -C 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg --traceback --config patch.eol='CRLF' import eol.diff
  applying eol.diff
  $ cat a
  a\r (esc)
  yyyy\r (esc)
  cc\r (esc)
  \r (esc)
  d\r (esc)
  e (no-eol)
  $ hg st


auto EOL on LF file

  $ hg up -C 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg --traceback --config patch.eol='auto' import eol.diff
  applying eol.diff
  $ cat a
  a
  yyyy
  cc
  
  d
  e (no-eol)
  $ hg st


auto EOL on CRLF file

  $ "$PYTHON" -c 'open("a", "wb").write(b"a\r\nbbb\r\ncc\r\n\r\nd\r\ne")'
  $ hg commit -m 'switch EOLs in a'
  $ hg --traceback --config patch.eol='auto' import eol.diff
  applying eol.diff
  $ cat a
  a\r (esc)
  yyyy\r (esc)
  cc\r (esc)
  \r (esc)
  d\r (esc)
  e (no-eol)
  $ hg st


auto EOL on new file or source without any EOL

  $ "$PYTHON" -c 'open("noeol", "wb").write(b"noeol")'
  $ hg add noeol
  $ hg commit -m 'add noeol'
  $ "$PYTHON" -c 'open("noeol", "wb").write(b"noeol\r\nnoeol\n")'
  $ "$PYTHON" -c 'open("neweol", "wb").write(b"neweol\nneweol\r\n")'
  $ hg add neweol
  $ hg diff --git > noeol.diff
  $ hg revert --no-backup noeol neweol
  $ rm neweol
  $ hg --traceback --config patch.eol='auto' import -m noeol noeol.diff
  applying noeol.diff
  $ cat noeol
  noeol\r (esc)
  noeol
  $ cat neweol
  neweol
  neweol\r (esc)
  $ hg st


Test --eol and binary patches

  $ "$PYTHON" -c 'open("b", "wb").write(b"a\x00\nb\r\nd")'
  $ hg ci -Am addb
  adding b
  $ "$PYTHON" -c 'open("b", "wb").write(b"a\x00\nc\r\nd")'
  $ hg diff --git > bin.diff
  $ hg revert --no-backup b

binary patch with --eol

  $ hg import --config patch.eol='CRLF' -m changeb bin.diff
  applying bin.diff
  $ cat b
  a\x00 (esc)
  c\r (esc)
  d (no-eol)
  $ hg st
  $ cd ..