view tests/test-diff-unified.t @ 32697:19b9fc40cc51

revlog: skeleton support for version 2 revlogs There are a number of improvements we want to make to revlogs that will require a new version - version 2. It is unclear what the full set of improvements will be or when we'll be done with them. What I do know is that the process will likely take longer than a single release, will require input from various stakeholders to evaluate changes, and will have many contentious debates and bikeshedding. It is unrealistic to develop revlog version 2 up front: there are just too many uncertainties that we won't know until things are implemented and experiments are run. Some changes will also be invasive and prone to bit rot, so sitting on dozens of patches is not practical. This commit introduces skeleton support for version 2 revlogs in a way that is flexible and not bound by backwards compatibility concerns. An experimental repo requirement for denoting revlog v2 has been added. The requirement string has a sub-version component to it. This will allow us to declare multiple requirements in the course of developing revlog v2. Whenever we change the in-development revlog v2 format, we can tweak the string, creating a new requirement and locking out old clients. This will allow us to make as many backwards incompatible changes and experiments to revlog v2 as we want. In other words, we can land code and make meaningful progress towards revlog v2 while still maintaining extreme format flexibility up until the point we freeze the format and remove the experimental labels. To enable the new repo requirement, you must supply an experimental and undocumented config option. But not just any boolean flag will do: you need to explicitly use a value that no sane person should ever type. This is an additional guard against enabling revlog v2 on an installation it shouldn't be enabled on. The specific scenario I'm trying to prevent is say a user with a 4.4 client with a frozen format enabling the option but then downgrading to 4.3 and accidentally creating repos with an outdated and unsupported repo format. Requiring a "challenge" string should prevent this. Because the format is not yet finalized and I don't want to take any chances, revlog v2's version is currently 0xDEAD. I figure squatting on a value we're likely never to use as an actual revlog version to mean "internal testing only" is acceptable. And "dead" is easily recognized as something meaningful. There is a bunch of cleanup that is needed before work on revlog v2 begins in earnest. I plan on doing that work once this patch is accepted and we're comfortable with the idea of starting down this path.
author Gregory Szorc <gregory.szorc@gmail.com>
date Fri, 19 May 2017 20:29:11 -0700
parents 897726622877
children 44c4a38bf563
line wrap: on
line source

  $ 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 ..