view tests/test-diff-unified.t @ 29859:a1092e2d70a3

help: internals topic for wire protocol

The Mercurial wire protocol is under-documented. This includes a lack
of source docstrings and comments as well as pages on the official
wiki.

This patch adds the beginnings of "internals" documentation on the
wire protocol.

The documentation should have nearly complete coverage on the
lower-level parts of the protocol, such as the different transport
mechanims, how commands and arguments are sent, capabilities, and,
of course, the commands themselves.

As part of writing this documentation, I discovered a number of
deficiencies in the protocol and bugs in the implementation. I've
started sending patches for some of the issues. I hope to send a lot
more.

This patch starts with the scaffolding for a new internals page.

  $ 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 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;
   }

  $ cd ..