view tests/test-diff-unified.t @ 40056:324b4b10351e

revlog: rewrite censoring logic

I was able to corrupt a revlog relatively easily with the existing
censoring code. The underlying problem is that the existing code
doesn't fully take delta chains into account. When copying revisions
that occur after the censored revision, the delta base can refer
to a censored revision. Then at read time, things blow up due to the
revision data not being a compressed delta.

This commit rewrites the revlog censoring code to take a higher-level
approach. We now create a new revlog instance pointing at temp files.
We iterate through each revision in the source revlog and insert
those revisions into the new revlog, replacing the censored revision's
data along the way.

The new implementation isn't as efficient as the old one. This is
because it will fully engage delta computation on insertion. But I
don't think it matters.

The new implementation is a bit hacky because it attempts to reload
the revlog instance with a new revlog index/data file. This is fragile.
But this is needed because the index (which could be backed by C) would
have a cached copy of the old, possibly changed data and that could
lead to problems accessing index or revision data later.

One benefit of the new approach is that we integrate with the
transaction. The old revlog is backed up and if the transaction is
rolled back, the original revlog is restored.

As part of this, we had to teach the transaction about the store
vfs. I'm not super keen about this. But this was the easiest way
to hook things up to the transaction. We /could/ just ignore the
transaction like we were doing before. But any file mutation should
be governed by transaction semantics, including undo during rollback.

Differential Revision: https://phab.mercurial-scm.org/D4869

  $ hg init repo
  $ cd repo
  $ cat > a <<EOF
  > c
  > c
  > a
  > a
  > b
  > a
  > a
  > c
  > c
  > EOF
  $ hg ci -Am adda
  adding a

  $ cat > a <<EOF
  > c
  > c
  > a
  > a
  > dd
  > a
  > a
  > c
  > c
  > EOF

default context

  $ hg diff --nodates
  diff -r cf9f4ba66af2 a
  --- a/a
  +++ b/a
  @@ -2,7 +2,7 @@
   c
   a
   a
  -b
  +dd
   a
   a
   c

invalid --unified

  $ hg diff --nodates -U foo
  abort: diff context lines count must be an integer, not 'foo'
  [255]


  $ hg diff --nodates -U 2
  diff -r cf9f4ba66af2 a
  --- a/a
  +++ b/a
  @@ -3,5 +3,5 @@
   a
   a
  -b
  +dd
   a
   a

  $ hg --config diff.unified=2 diff --nodates
  diff -r cf9f4ba66af2 a
  --- a/a
  +++ b/a
  @@ -3,5 +3,5 @@
   a
   a
  -b
  +dd
   a
   a

  $ hg diff --nodates -U 1
  diff -r cf9f4ba66af2 a
  --- a/a
  +++ b/a
  @@ -4,3 +4,3 @@
   a
  -b
  +dd
   a

invalid diff.unified

  $ hg --config diff.unified=foo diff --nodates
  abort: diff context lines count must be an integer, not 'foo'
  [255]

noprefix config and option

  $ hg --config diff.noprefix=True diff --nodates
  diff -r cf9f4ba66af2 a
  --- a
  +++ a
  @@ -2,7 +2,7 @@
   c
   a
   a
  -b
  +dd
   a
   a
   c
  $ hg diff --noprefix --nodates
  diff -r cf9f4ba66af2 a
  --- a
  +++ a
  @@ -2,7 +2,7 @@
   c
   a
   a
  -b
  +dd
   a
   a
   c

noprefix config disabled in plain mode, but option still enabled

  $ HGPLAIN=1 hg --config diff.noprefix=True diff --nodates
  diff -r cf9f4ba66af2 a
  --- a/a
  +++ b/a
  @@ -2,7 +2,7 @@
   c
   a
   a
  -b
  +dd
   a
   a
   c
  $ HGPLAIN=1 hg diff --noprefix --nodates
  diff -r cf9f4ba66af2 a
  --- a
  +++ a
  @@ -2,7 +2,7 @@
   c
   a
   a
  -b
  +dd
   a
   a
   c

  $ cd ..


0 lines of context hunk header matches gnu diff hunk header

  $ hg init diffzero
  $ cd diffzero
  $ cat > f1 << EOF
  > c2
  > c4
  > c5
  > EOF
  $ hg commit -Am0
  adding f1

  $ cat > f2 << EOF
  > c1
  > c2
  > c3
  > c4
  > EOF
  $ mv f2 f1
  $ hg diff -U0 --nodates
  diff -r 55d8ff78db23 f1
  --- a/f1
  +++ b/f1
  @@ -0,0 +1,1 @@
  +c1
  @@ -1,0 +3,1 @@
  +c3
  @@ -3,1 +4,0 @@
  -c5

  $ hg diff -U0 --nodates --git
  diff --git a/f1 b/f1
  --- a/f1
  +++ b/f1
  @@ -0,0 +1,1 @@
  +c1
  @@ -1,0 +3,1 @@
  +c3
  @@ -3,1 +4,0 @@
  -c5

  $ hg diff -U0 --nodates -p
  diff -r 55d8ff78db23 f1
  --- a/f1
  +++ b/f1
  @@ -0,0 +1,1 @@
  +c1
  @@ -1,0 +3,1 @@ c2
  +c3
  @@ -3,1 +4,0 @@ c4
  -c5

  $ echo a > f1
  $ hg ci -m movef2

Test diff headers terminating with TAB when necessary (issue3357)
Regular diff --nodates, file creation

  $ hg mv f1 'f 1'
  $ echo b > 'f 1'
  $ hg diff --nodates 'f 1'
  diff -r 7574207d0d15 f 1
  --- /dev/null
  +++ b/f 1	
  @@ -0,0 +1,1 @@
  +b

Git diff, adding space

  $ hg diff --git
  diff --git a/f1 b/f 1
  rename from f1
  rename to f 1
  --- a/f1
  +++ b/f 1	
  @@ -1,1 +1,1 @@
  -a
  +b

Git diff, adding extended headers

  $ hg diff --git --config experimental.extendedheader.index=7 --config experimental.extendedheader.similarity=True
  diff --git a/f1 b/f 1
  similarity index 0%
  rename from f1
  rename to f 1
  index 7898192..6178079 100644
  --- a/f1
  +++ b/f 1	
  @@ -1,1 +1,1 @@
  -a
  +b

  $ hg diff --git --config experimental.extendedheader.index=-1
  invalid length for extendedheader.index: '-1'
  diff --git a/f1 b/f 1
  rename from f1
  rename to f 1
  --- a/f1
  +++ b/f 1	
  @@ -1,1 +1,1 @@
  -a
  +b

  $ hg diff --git --config experimental.extendedheader.index=whatever
  invalid value for extendedheader.index: 'whatever'
  diff --git a/f1 b/f 1
  rename from f1
  rename to f 1
  --- a/f1
  +++ b/f 1	
  @@ -1,1 +1,1 @@
  -a
  +b

Git diff with noprefix

  $ hg --config diff.noprefix=True diff --git --nodates
  diff --git f1 f 1
  rename from f1
  rename to f 1
  --- f1
  +++ f 1	
  @@ -1,1 +1,1 @@
  -a
  +b

noprefix config disabled in plain mode, but option still enabled

  $ HGPLAIN=1 hg --config diff.noprefix=True diff --git --nodates
  diff --git a/f1 b/f 1
  rename from f1
  rename to f 1
  --- a/f1
  +++ b/f 1	
  @@ -1,1 +1,1 @@
  -a
  +b
  $ HGPLAIN=1 hg diff --git --noprefix --nodates
  diff --git f1 f 1
  rename from f1
  rename to f 1
  --- f1
  +++ f 1	
  @@ -1,1 +1,1 @@
  -a
  +b

Regular diff --nodates, file deletion

  $ hg ci -m addspace
  $ hg mv 'f 1' f1
  $ echo a > f1
  $ hg diff --nodates 'f 1'
  diff -r ca50fe67c9c7 f 1
  --- a/f 1	
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -b

Git diff, removing space

  $ hg diff --git
  diff --git a/f 1 b/f1
  rename from f 1
  rename to f1
  --- a/f 1	
  +++ b/f1
  @@ -1,1 +1,1 @@
  -b
  +a

showfunc diff
  $ cat > f1 << EOF
  > int main() {
  >     int a = 0;
  >     int b = 1;
  >     int c = 2;
  >     int d = 3;
  >     return a + b + c + d;
  > }
  > EOF
  $ hg commit -m addfunction
  $ cat > f1 << EOF
  > int main() {
  >     int a = 0;
  >     int b = 1;
  >     int c = 2;
  >     int e = 3;
  >     return a + b + c + e;
  > }
  > EOF
  $ hg diff --git
  diff --git a/f1 b/f1
  --- a/f1
  +++ b/f1
  @@ -2,6 +2,6 @@
       int a = 0;
       int b = 1;
       int c = 2;
  -    int d = 3;
  -    return a + b + c + d;
  +    int e = 3;
  +    return a + b + c + e;
   }
  $ hg diff --config diff.showfunc=True --git
  diff --git a/f1 b/f1
  --- a/f1
  +++ b/f1
  @@ -2,6 +2,6 @@ int main() {
       int a = 0;
       int b = 1;
       int c = 2;
  -    int d = 3;
  -    return a + b + c + d;
  +    int e = 3;
  +    return a + b + c + e;
   }

If [diff] git is set to true, but the user says --no-git, we should
*not* get git diffs
  $ hg diff --nodates --config diff.git=1 --no-git
  diff -r f2c7c817fa55 f1
  --- a/f1
  +++ b/f1
  @@ -2,6 +2,6 @@
       int a = 0;
       int b = 1;
       int c = 2;
  -    int d = 3;
  -    return a + b + c + d;
  +    int e = 3;
  +    return a + b + c + e;
   }

  $ cd ..

Long function names should be abbreviated, but multi-byte character shouldn't
be broken up

  $ hg init longfunc
  $ cd longfunc

  >>> with open('a', 'wb') as f:
  ...     f.write(b'a' * 39 + b'bb' + b'\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b' 0 b\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b'a' * 39 + b'\xc3\xa0' + b'\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b' 0 a with grave (single code point)\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b'a' * 39 + b'a\xcc\x80' + b'\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b' 0 a with grave (composition)\n') and None
  ...     f.write(b' .\n' * 3) and None
  $ hg ci -qAm0

  >>> with open('a', 'wb') as f:
  ...     f.write(b'a' * 39 + b'bb' + b'\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b' 1 b\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b'a' * 39 + b'\xc3\xa0' + b'\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b' 1 a with grave (single code point)\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b'a' * 39 + b'a\xcc\x80' + b'\n') and None
  ...     f.write(b' .\n' * 3) and None
  ...     f.write(b' 1 a with grave (composition)\n') and None
  ...     f.write(b' .\n' * 3) and None
  $ hg ci -m1

  $ hg diff -c1 --nodates --show-function
  diff -r 3e92dd6fa812 -r a256341606cb a
  --- a/a
  +++ b/a
  @@ -2,7 +2,7 @@ aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaab
    .
    .
    .
  - 0 b
  + 1 b
    .
    .
    .
  @@ -10,7 +10,7 @@ aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\xc3\xa0 (esc)
    .
    .
    .
  - 0 a with grave (single code point)
  + 1 a with grave (single code point)
    .
    .
    .
  @@ -18,7 +18,7 @@ aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\xcc\x80 (esc)
    .
    .
    .
  - 0 a with grave (composition)
  + 1 a with grave (composition)
    .
    .
    .

  $ cd ..