view tests/test-git-export.t @ 35884:197d10e157ce

httppeer: remove support for connecting to <0.9.1 servers (BC)

Previously, HTTP wire protocol clients would attempt a
"capabilities" wire protocol command. If that failed, they would
fall back to issuing a "between" command.

The "capabilities" command was added in Mercurial 0.9.1 (released
July 2006). The "between" command has been present for as long as
the wire protocol has existed. So if the "between" command failed,
it was safe to assume that the remote could not speak any version
of the Mercurial wire protocol.

The "between" fallback was added in 395a84f78736 in 2011. Before that
changeset, Mercurial would *always* issue the "between" command and
would issue "capabilities" if capabilities were requested. At that time,
many connections would issue "capabilities" eventually, so it was
decided to issue "capabilities" by default and fall back to "between"
if that failed. This saved a round trip when connecting to modern
servers while still preserving compatibility with legacy servers.

Fast forward ~7 years. Mercurial servers supporting "capabilities"
have been around for over a decade. If modern clients are
connecting to <0.9.1 servers, they are getting a bad experience.
They may even be getting bad data (an old server is vulnerable to
numerous security issues and could have been p0wned, leading to a
Mercurial repository serving backdoors or other badness).

In addition, the fallback can harm experience for modern servers.
If a client experiences an intermittent HTTP request failure (due to
bad network, etc) and falls back to a "between" that works, it would
assume an empty capability set and would attempt to communicate with
the repository using a very ancient wire protocol. Auditing HTTP logs
for hg.mozilla.org, I did find a handful of requests for the
null range of the "between" command. However, requests can be days
apart. And when I do see requests, they come in batches. Those
batches seem to correlate to spikes of HTTP 500 or other
server/network events. So I think these requests are fallbacks from
failed "capabilities" requests and not from old clients.

If you need even more evidence to discontinue support, apparently
we have no test coverage for communicating with servers not
supporting "capabilities." I know this because all tests pass
with the "between" fallback removed.

Finally, server-side support for <0.9.1 pushing (the "addchangegroup"
wire protocol command along with locking-related commands) was dropped
from the HTTP client in fda0867cfe03 in 2017 and the SSH client in
9f6e0e7ef828 in 2015.

I think this all adds up to enough justification for removing client
support for communicating with servers not supporting "capabilities."
So this commit removes that fallback.

Differential Revision: https://phab.mercurial-scm.org/D2001

  $ hg init
  $ echo start > start
  $ hg ci -Amstart
  adding start

New file:

  $ mkdir dir1
  $ echo new > dir1/new
  $ hg ci -Amnew
  adding dir1/new
  $ hg diff --git -r 0
  diff --git a/dir1/new b/dir1/new
  new file mode 100644
  --- /dev/null
  +++ b/dir1/new
  @@ -0,0 +1,1 @@
  +new

Copy:

  $ mkdir dir2
  $ hg cp dir1/new dir1/copy
  $ echo copy1 >> dir1/copy
  $ hg cp dir1/new dir2/copy
  $ echo copy2 >> dir2/copy
  $ hg ci -mcopy
  $ hg diff --git -r 1:tip
  diff --git a/dir1/new b/dir1/copy
  copy from dir1/new
  copy to dir1/copy
  --- a/dir1/new
  +++ b/dir1/copy
  @@ -1,1 +1,2 @@
   new
  +copy1
  diff --git a/dir1/new b/dir2/copy
  copy from dir1/new
  copy to dir2/copy
  --- a/dir1/new
  +++ b/dir2/copy
  @@ -1,1 +1,2 @@
   new
  +copy2

Cross and same-directory copies with a relative root:

  $ hg diff --git --root .. -r 1:tip
  abort: .. not under root '$TESTTMP'
  [255]
  $ hg diff --git --root doesnotexist -r 1:tip
  $ hg diff --git --root . -r 1:tip
  diff --git a/dir1/new b/dir1/copy
  copy from dir1/new
  copy to dir1/copy
  --- a/dir1/new
  +++ b/dir1/copy
  @@ -1,1 +1,2 @@
   new
  +copy1
  diff --git a/dir1/new b/dir2/copy
  copy from dir1/new
  copy to dir2/copy
  --- a/dir1/new
  +++ b/dir2/copy
  @@ -1,1 +1,2 @@
   new
  +copy2
  $ hg diff --git --root dir1 -r 1:tip
  diff --git a/new b/copy
  copy from new
  copy to copy
  --- a/new
  +++ b/copy
  @@ -1,1 +1,2 @@
   new
  +copy1

  $ hg diff --git --root dir2/ -r 1:tip
  diff --git a/copy b/copy
  new file mode 100644
  --- /dev/null
  +++ b/copy
  @@ -0,0 +1,2 @@
  +new
  +copy2

  $ hg diff --git --root dir1 -r 1:tip -I '**/copy'
  diff --git a/new b/copy
  copy from new
  copy to copy
  --- a/new
  +++ b/copy
  @@ -1,1 +1,2 @@
   new
  +copy1

  $ hg diff --git --root dir1 -r 1:tip dir2
  warning: dir2 not inside relative root dir1

  $ hg diff --git --root dir1 -r 1:tip 'dir2/{copy}'
  warning: dir2/{copy} not inside relative root dir1

  $ cd dir1
  $ hg diff --git --root .. -r 1:tip
  diff --git a/dir1/new b/dir1/copy
  copy from dir1/new
  copy to dir1/copy
  --- a/dir1/new
  +++ b/dir1/copy
  @@ -1,1 +1,2 @@
   new
  +copy1
  diff --git a/dir1/new b/dir2/copy
  copy from dir1/new
  copy to dir2/copy
  --- a/dir1/new
  +++ b/dir2/copy
  @@ -1,1 +1,2 @@
   new
  +copy2

  $ hg diff --git --root ../.. -r 1:tip
  abort: ../.. not under root '$TESTTMP'
  [255]
  $ hg diff --git --root ../doesnotexist -r 1:tip
  $ hg diff --git --root .. -r 1:tip
  diff --git a/dir1/new b/dir1/copy
  copy from dir1/new
  copy to dir1/copy
  --- a/dir1/new
  +++ b/dir1/copy
  @@ -1,1 +1,2 @@
   new
  +copy1
  diff --git a/dir1/new b/dir2/copy
  copy from dir1/new
  copy to dir2/copy
  --- a/dir1/new
  +++ b/dir2/copy
  @@ -1,1 +1,2 @@
   new
  +copy2

  $ hg diff --git --root . -r 1:tip
  diff --git a/new b/copy
  copy from new
  copy to copy
  --- a/new
  +++ b/copy
  @@ -1,1 +1,2 @@
   new
  +copy1
  $ hg diff --git --root . -r 1:tip copy
  diff --git a/new b/copy
  copy from new
  copy to copy
  --- a/new
  +++ b/copy
  @@ -1,1 +1,2 @@
   new
  +copy1
  $ hg diff --git --root . -r 1:tip ../dir2
  warning: ../dir2 not inside relative root .
  $ hg diff --git --root . -r 1:tip '../dir2/*'
  warning: ../dir2/* not inside relative root . (glob)
  $ cd ..

Rename:

  $ hg mv dir1/copy dir1/rename1
  $ echo rename1 >> dir1/rename1
  $ hg mv dir2/copy dir1/rename2
  $ echo rename2 >> dir1/rename2
  $ hg ci -mrename
  $ hg diff --git -r 2:tip
  diff --git a/dir1/copy b/dir1/rename1
  rename from dir1/copy
  rename to dir1/rename1
  --- a/dir1/copy
  +++ b/dir1/rename1
  @@ -1,2 +1,3 @@
   new
   copy1
  +rename1
  diff --git a/dir2/copy b/dir1/rename2
  rename from dir2/copy
  rename to dir1/rename2
  --- a/dir2/copy
  +++ b/dir1/rename2
  @@ -1,2 +1,3 @@
   new
   copy2
  +rename2

Cross and same-directory renames with a relative root:

  $ hg diff --root dir1 --git -r 2:tip
  diff --git a/copy b/rename1
  rename from copy
  rename to rename1
  --- a/copy
  +++ b/rename1
  @@ -1,2 +1,3 @@
   new
   copy1
  +rename1
  diff --git a/rename2 b/rename2
  new file mode 100644
  --- /dev/null
  +++ b/rename2
  @@ -0,0 +1,3 @@
  +new
  +copy2
  +rename2

  $ hg diff --root dir2 --git -r 2:tip
  diff --git a/copy b/copy
  deleted file mode 100644
  --- a/copy
  +++ /dev/null
  @@ -1,2 +0,0 @@
  -new
  -copy2

  $ hg diff --root dir1 --git -r 2:tip -I '**/copy'
  diff --git a/copy b/copy
  deleted file mode 100644
  --- a/copy
  +++ /dev/null
  @@ -1,2 +0,0 @@
  -new
  -copy1

  $ hg diff --root dir1 --git -r 2:tip -I '**/rename*'
  diff --git a/copy b/rename1
  copy from copy
  copy to rename1
  --- a/copy
  +++ b/rename1
  @@ -1,2 +1,3 @@
   new
   copy1
  +rename1
  diff --git a/rename2 b/rename2
  new file mode 100644
  --- /dev/null
  +++ b/rename2
  @@ -0,0 +1,3 @@
  +new
  +copy2
  +rename2

Delete:

  $ hg rm dir1/*
  $ hg ci -mdelete
  $ hg diff --git -r 3:tip
  diff --git a/dir1/new b/dir1/new
  deleted file mode 100644
  --- a/dir1/new
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -new
  diff --git a/dir1/rename1 b/dir1/rename1
  deleted file mode 100644
  --- a/dir1/rename1
  +++ /dev/null
  @@ -1,3 +0,0 @@
  -new
  -copy1
  -rename1
  diff --git a/dir1/rename2 b/dir1/rename2
  deleted file mode 100644
  --- a/dir1/rename2
  +++ /dev/null
  @@ -1,3 +0,0 @@
  -new
  -copy2
  -rename2

  $ cat > src <<EOF
  > 1
  > 2
  > 3
  > 4
  > 5
  > EOF
  $ hg ci -Amsrc
  adding src

#if execbit

chmod 644:

  $ chmod +x src
  $ hg ci -munexec
  $ hg diff --git -r 5:tip
  diff --git a/src b/src
  old mode 100644
  new mode 100755

Rename+mod+chmod:

  $ hg mv src dst
  $ chmod -x dst
  $ echo a >> dst
  $ hg ci -mrenamemod
  $ hg diff --git -r 6:tip
  diff --git a/src b/dst
  old mode 100755
  new mode 100644
  rename from src
  rename to dst
  --- a/src
  +++ b/dst
  @@ -3,3 +3,4 @@
   3
   4
   5
  +a

Nonexistent in tip+chmod:

  $ hg diff --git -r 5:6
  diff --git a/src b/src
  old mode 100644
  new mode 100755

#else

Dummy changes when no exec bit, mocking the execbit commit structure

  $ echo change >> src
  $ hg ci -munexec
  $ hg mv src dst
  $ hg ci -mrenamemod

#endif

Binary diff:

  $ cp "$TESTDIR/binfile.bin" .
  $ hg add binfile.bin
  $ hg diff --git > b.diff
  $ cat b.diff
  diff --git a/binfile.bin b/binfile.bin
  new file mode 100644
  index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..37ba3d1c6f17137d9c5f5776fa040caf5fe73ff9
  GIT binary patch
  literal 593
  zc$@)I0<QguP)<h;3K|Lk000e1NJLTq000mG000mO0ssI2kdbIM00009a7bBm000XU
  z000XU0RWnu7ytkO2XskIMF-Uh9TW;VpMjwv0005-Nkl<ZD9@FWPs=e;7{<>W$NUkd
  zX$nnYLt$-$V!?uy+1V%`z&Eh=ah|duER<4|QWhju3gb^nF*8iYobxWG-qqXl=2~5M
  z*IoDB)sG^CfNuoBmqLTVU^<;@nwHP!1wrWd`{(mHo6VNXWtyh{alzqmsH*yYzpvLT
  zLdY<T=ks|woh-`&01!ej#(xbV1f|pI*=%;d-%F*E*X#ZH`4I%6SS+$EJDE&ct=8po
  ziN#{?_j|kD%Cd|oiqds`xm@;oJ-^?NG3Gdqrs?5u*zI;{nogxsx~^|Fn^Y?Gdc6<;
  zfMJ+iF1J`LMx&A2?dEwNW8ClebzPTbIh{@$hS6*`kH@1d%Lo7fA#}N1)oN7`gm$~V
  z+wDx#)OFqMcE{s!JN0-xhG8ItAjVkJwEcb`3WWlJfU2r?;Pd%dmR+q@mSri5q9_W-
  zaR2~ECX?B2w+zELozC0s*6Z~|QG^f{3I#<`?)Q7U-JZ|q5W;9Q8i_=pBuSzunx=U;
  z9C)5jBoYw9^?EHyQl(M}1OlQcCX>lXB*ODN003Z&P17_@)3Pi=i0wb04<W?v-u}7K
  zXmmQA+wDgE!qR9o8jr`%=ab_&uh(l?R=r;Tjiqon91I2-hIu?57~@*4h7h9uORK#=
  fQItJW-{SoTm)8|5##k|m00000NkvXXu0mjf{mKw4
  

Import binary diff:

  $ hg revert binfile.bin
  $ rm binfile.bin
  $ hg import -mfoo b.diff
  applying b.diff
  $ cmp binfile.bin "$TESTDIR/binfile.bin"

Rename binary file:

  $ hg mv binfile.bin renamed.bin
  $ hg diff --git
  diff --git a/binfile.bin b/renamed.bin
  rename from binfile.bin
  rename to renamed.bin

Diff across many revisions:

  $ hg mv dst dst2
  $ hg ci -m 'mv dst dst2'

  $ echo >> start
  $ hg ci -m 'change start'

  $ hg revert -r -2 start
  $ hg mv dst2 dst3
  $ hg ci -m 'mv dst2 dst3; revert start'

  $ hg diff --git -r 9:11
  diff --git a/dst2 b/dst3
  rename from dst2
  rename to dst3

Reversed:

  $ hg diff --git -r 11:9
  diff --git a/dst3 b/dst2
  rename from dst3
  rename to dst2


  $ echo a >> foo
  $ hg add foo
  $ hg ci -m 'add foo'
  $ echo b >> foo
  $ hg ci -m 'change foo'
  $ hg mv foo bar
  $ hg ci -m 'mv foo bar'
  $ echo c >> bar
  $ hg ci -m 'change bar'

File created before r1 and renamed before r2:

  $ hg diff --git -r -3:-1
  diff --git a/foo b/bar
  rename from foo
  rename to bar
  --- a/foo
  +++ b/bar
  @@ -1,2 +1,3 @@
   a
   b
  +c

Reversed:

  $ hg diff --git -r -1:-3
  diff --git a/bar b/foo
  rename from bar
  rename to foo
  --- a/bar
  +++ b/foo
  @@ -1,3 +1,2 @@
   a
   b
  -c

File created in r1 and renamed before r2:

  $ hg diff --git -r -4:-1
  diff --git a/foo b/bar
  rename from foo
  rename to bar
  --- a/foo
  +++ b/bar
  @@ -1,1 +1,3 @@
   a
  +b
  +c

Reversed:

  $ hg diff --git -r -1:-4
  diff --git a/bar b/foo
  rename from bar
  rename to foo
  --- a/bar
  +++ b/foo
  @@ -1,3 +1,1 @@
   a
  -b
  -c

File created after r1 and renamed before r2:

  $ hg diff --git -r -5:-1
  diff --git a/bar b/bar
  new file mode 100644
  --- /dev/null
  +++ b/bar
  @@ -0,0 +1,3 @@
  +a
  +b
  +c

Reversed:

  $ hg diff --git -r -1:-5
  diff --git a/bar b/bar
  deleted file mode 100644
  --- a/bar
  +++ /dev/null
  @@ -1,3 +0,0 @@
  -a
  -b
  -c


Comparing with the working dir:

  $ echo >> start
  $ hg ci -m 'change start again'

  $ echo > created
  $ hg add created
  $ hg ci -m 'add created'

  $ hg mv created created2
  $ hg ci -m 'mv created created2'

  $ hg mv created2 created3

There's a copy in the working dir:

  $ hg diff --git
  diff --git a/created2 b/created3
  rename from created2
  rename to created3

There's another copy between the original rev and the wd:

  $ hg diff --git -r -2
  diff --git a/created b/created3
  rename from created
  rename to created3

The source of the copy was created after the original rev:

  $ hg diff --git -r -3
  diff --git a/created3 b/created3
  new file mode 100644
  --- /dev/null
  +++ b/created3
  @@ -0,0 +1,1 @@
  +
  $ hg ci -m 'mv created2 created3'


  $ echo > brand-new
  $ hg add brand-new
  $ hg ci -m 'add brand-new'
  $ hg mv brand-new brand-new2

Created in parent of wd; renamed in the wd:

  $ hg diff --git
  diff --git a/brand-new b/brand-new2
  rename from brand-new
  rename to brand-new2

Created between r1 and parent of wd; renamed in the wd:

  $ hg diff --git -r -2
  diff --git a/brand-new2 b/brand-new2
  new file mode 100644
  --- /dev/null
  +++ b/brand-new2
  @@ -0,0 +1,1 @@
  +
  $ hg ci -m 'mv brand-new brand-new2'

One file is copied to many destinations and removed:

  $ hg cp brand-new2 brand-new3
  $ hg mv brand-new2 brand-new3-2
  $ hg ci -m 'multiple renames/copies'
  $ hg diff --git -r -2 -r -1
  diff --git a/brand-new2 b/brand-new3
  rename from brand-new2
  rename to brand-new3
  diff --git a/brand-new2 b/brand-new3-2
  copy from brand-new2
  copy to brand-new3-2

Reversed:

  $ hg diff --git -r -1 -r -2
  diff --git a/brand-new3-2 b/brand-new2
  rename from brand-new3-2
  rename to brand-new2
  diff --git a/brand-new3 b/brand-new3
  deleted file mode 100644
  --- a/brand-new3
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -

There should be a trailing TAB if there are spaces in the file name:

  $ echo foo > 'with spaces'
  $ hg add 'with spaces'
  $ hg diff --git
  diff --git a/with spaces b/with spaces
  new file mode 100644
  --- /dev/null
  +++ b/with spaces	
  @@ -0,0 +1,1 @@
  +foo
  $ hg ci -m 'add filename with spaces'

Additions should be properly marked even in the middle of a merge

  $ hg up -r -2
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo "New File" >> inmerge
  $ hg add inmerge
  $ hg ci -m "file in merge"
  created new head
  $ hg up 23
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg merge
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg diff -g
  diff --git a/inmerge b/inmerge
  new file mode 100644
  --- /dev/null
  +++ b/inmerge
  @@ -0,0 +1,1 @@
  +New File