view tests/test-convert-svn-sink.t @ 36426:23d12524a202

http: drop custom http client logic

Eight and a half years ago, as my starter bug on code.google.com, I
investigated a mysterious "broken pipe" error from seemingly random
clients[0]. That investigation revealed a tragic story: the Python
standard library's httplib was (and remains) barely functional. During
large POSTs, if a server responds early with an error (even a
permission denied error!) the client only notices that the server
closed the connection and everything breaks. Such server behavior is
implicitly legal under RFC 2616 (the latest HTTP RFC as of when I was
last working on this), and my understanding is that later RFCs have
made it explicitly legal to respond early with any status code outside
the 2xx range.

I embarked, probably foolishly, on a journey to write a new http
library with better overall behavior. The http library appears to work
well in most cases, but it can get confused in the presence of
proxies, and it depends on select(2) which limits its utility if a lot
of file descriptors are open. I haven't touched the http library in
almost two years, and in the interim the Python community has
discovered a better way[1] of writing network code. In theory some day
urllib3 will have its own home-grown http library built on h11[2], or
we could do that. Either way, it's time to declare our current
confusingly-named "http2" client logic and move on. I do hope to
revisit this some day: it's still garbage that we can't even respond
with a 401 or 403 without reading the entire POST body from the
client, but the goalposts on writing a new http client library have
moved substantially. We're almost certainly better off just switching
to requests and eventually picking up their http fixes than trying to
live with something that realistically only we'll ever use. Another
approach would be to write an adapter so that Mercurial can use pycurl
if it's installed. Neither of those approaches seem like they should
be investigated prior to a release of Mercurial that works on Python
3: that's where the mindshare is going to be for any improvements to
the state of the http client art.

0: http://web.archive.org/web/20130501031801/http://code.google.com/p/support/issues/detail?id=2716
1: http://sans-io.readthedocs.io/
2: https://github.com/njsmith/h11

Differential Revision: https://phab.mercurial-scm.org/D2444

#require svn13

  $ svnupanddisplay()
  > {
  >     (
  >        cd $1;
  >        svn up -q;
  >        svn st -v | sed 's/  */ /g' | sort
  >        limit=''
  >        if [ $2 -gt 0 ]; then
  >            limit="--limit=$2"
  >        fi
  >        svn log --xml -v $limit | $PYTHON "$TESTDIR/svnxml.py"
  >     )
  > }

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > convert =
  > EOF

  $ hg init a

Add

  $ echo a > a/a
  $ mkdir -p a/d1/d2
  $ echo b > a/d1/d2/b
  $ hg --cwd a ci -d '0 0' -A -m 'add a file'
  adding a
  adding d1/d2/b

Modify

  $ svn-safe-append.py a a/a
  $ hg --cwd a ci -d '1 0' -m 'modify a file'
  $ hg --cwd a tip -q
  1:e0e2b8a9156b

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn repository 'a-hg'
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  1 add a file
  0 modify a file
  $ svnupanddisplay a-hg-wc 2
   2 1 test d1
   2 1 test d1/d2
   2 1 test d1/d2/b
   2 2 test .
   2 2 test a
  revision: 2
  author: test
  msg: modify a file
   M /a
  revision: 1
  author: test
  msg: add a file
   A /a
   A /d1
   A /d1/d2
   A /d1/d2/b
  $ ls a a-hg-wc
  a:
  a
  d1
  
  a-hg-wc:
  a
  d1
  $ cmp a/a a-hg-wc/a

Rename

  $ hg --cwd a mv a b
  $ hg --cwd a ci -d '2 0' -m 'rename a file'
  $ hg --cwd a tip -q
  2:eb5169441d43

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 rename a file
  $ svnupanddisplay a-hg-wc 1
   3 1 test d1
   3 1 test d1/d2
   3 1 test d1/d2/b
   3 3 test .
   3 3 test b
  revision: 3
  author: test
  msg: rename a file
   D /a
   A /b (from /a@2)
  $ ls a a-hg-wc
  a:
  b
  d1
  
  a-hg-wc:
  b
  d1

Copy

  $ hg --cwd a cp b c

  $ hg --cwd a ci -d '3 0' -m 'copy a file'
  $ hg --cwd a tip -q
  3:60effef6ab48

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 copy a file
  $ svnupanddisplay a-hg-wc 1
   4 1 test d1
   4 1 test d1/d2
   4 1 test d1/d2/b
   4 3 test b
   4 4 test .
   4 4 test c
  revision: 4
  author: test
  msg: copy a file
   A /c (from /b@3)
  $ ls a a-hg-wc
  a:
  b
  c
  d1
  
  a-hg-wc:
  b
  c
  d1

  $ hg --cwd a rm b

Remove

  $ hg --cwd a ci -d '4 0' -m 'remove a file'
  $ hg --cwd a tip -q
  4:87bbe3013fb6

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 remove a file
  $ svnupanddisplay a-hg-wc 1
   5 1 test d1
   5 1 test d1/d2
   5 1 test d1/d2/b
   5 4 test c
   5 5 test .
  revision: 5
  author: test
  msg: remove a file
   D /b
  $ ls a a-hg-wc
  a:
  c
  d1
  
  a-hg-wc:
  c
  d1

Executable

#if execbit
  $ chmod +x a/c
#else
  $ echo fake >> a/c
#endif
  $ hg --cwd a ci -d '5 0' -m 'make a file executable'
#if execbit
  $ hg --cwd a tip -q
  5:ff42e473c340
#else
  $ hg --cwd a tip -q
  5:817a700c8cf1
#endif

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 make a file executable
  $ svnupanddisplay a-hg-wc 1
   6 1 test d1
   6 1 test d1/d2
   6 1 test d1/d2/b
   6 6 test .
   6 6 test c
  revision: 6
  author: test
  msg: make a file executable
   M /c
#if execbit
  $ test -x a-hg-wc/c
#endif

#if symlink

Symlinks

  $ ln -s a/missing a/link
  $ hg --cwd a commit -Am 'add symlink'
  adding link
  $ hg --cwd a mv link newlink
  $ hg --cwd a commit -m 'move symlink'
  $ hg convert -d svn a a-svnlink
  initializing svn repository 'a-svnlink'
  initializing svn working copy 'a-svnlink-wc'
  scanning source...
  sorting...
  converting...
  7 add a file
  6 modify a file
  5 rename a file
  4 copy a file
  3 remove a file
  2 make a file executable
  1 add symlink
  0 move symlink
  $ svnupanddisplay a-svnlink-wc 1
   8 1 test d1
   8 1 test d1/d2
   8 1 test d1/d2/b
   8 6 test c
   8 8 test .
   8 8 test newlink
  revision: 8
  author: test
  msg: move symlink
   D /link
   A /newlink (from /link@7)

Make sure our changes don't affect the rest of the test cases

  $ hg --cwd a up 5
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg --cwd a --config extensions.strip= strip -r 6
  saved backup bundle to $TESTTMP/a/.hg/strip-backup/bd4f7b7a7067-ed505e42-backup.hg

#endif

Convert with --full adds and removes files that didn't change

  $ touch a/f
  $ hg -R a ci -Aqmf
  $ echo "rename c d" > filemap
  $ hg convert -d svn a --filemap filemap --full
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 f
  $ svnupanddisplay a-hg-wc 1
   7 7 test .
   7 7 test d
   7 7 test f
  revision: 7
  author: test
  msg: f
   D /c
   A /d
   D /d1
   A /f

  $ rm -rf a a-hg a-hg-wc


Executable in new directory

  $ hg init a

  $ mkdir a/d1
  $ echo a > a/d1/a
#if execbit
  $ chmod +x a/d1/a
#else
  $ echo fake >> a/d1/a
#endif
  $ hg --cwd a ci -d '0 0' -A -m 'add executable file in new directory'
  adding d1/a

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn repository 'a-hg'
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 add executable file in new directory
  $ svnupanddisplay a-hg-wc 1
   1 1 test .
   1 1 test d1
   1 1 test d1/a
  revision: 1
  author: test
  msg: add executable file in new directory
   A /d1
   A /d1/a
#if execbit
  $ test -x a-hg-wc/d1/a
#endif

Copy to new directory

  $ mkdir a/d2
  $ hg --cwd a cp d1/a d2/a
  $ hg --cwd a ci -d '1 0' -A -m 'copy file to new directory'

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  0 copy file to new directory
  $ svnupanddisplay a-hg-wc 1
   2 1 test d1
   2 1 test d1/a
   2 2 test .
   2 2 test d2
   2 2 test d2/a
  revision: 2
  author: test
  msg: copy file to new directory
   A /d2
   A /d2/a (from /d1/a@1)

Branchy history

  $ hg init b
  $ echo base > b/b
  $ hg --cwd b ci -d '0 0' -Ambase
  adding b

  $ svn-safe-append.py left-1 b/b
  $ echo left-1 > b/left-1
  $ hg --cwd b ci -d '1 0' -Amleft-1
  adding left-1

  $ svn-safe-append.py left-2 b/b
  $ echo left-2 > b/left-2
  $ hg --cwd b ci -d '2 0' -Amleft-2
  adding left-2

  $ hg --cwd b up 0
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

  $ svn-safe-append.py right-1 b/b
  $ echo right-1 > b/right-1
  $ hg --cwd b ci -d '3 0' -Amright-1
  adding right-1
  created new head

  $ svn-safe-append.py right-2 b/b
  $ echo right-2 > b/right-2
  $ hg --cwd b ci -d '4 0' -Amright-2
  adding right-2

  $ hg --cwd b up -C 2
  3 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ hg --cwd b merge
  merging b
  warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
  2 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
  [1]
  $ hg --cwd b revert -r 2 b
  $ hg --cwd b resolve -m b
  (no more unresolved files)
  $ hg --cwd b ci -d '5 0' -m 'merge'

Expect 4 changes

  $ hg convert -d svn b
  assuming destination b-hg
  initializing svn repository 'b-hg'
  initializing svn working copy 'b-hg-wc'
  scanning source...
  sorting...
  converting...
  5 base
  4 left-1
  3 left-2
  2 right-1
  1 right-2
  0 merge

  $ svnupanddisplay b-hg-wc 0
   4 2 test left-1
   4 3 test b
   4 3 test left-2
   4 4 test .
   4 4 test right-1
   4 4 test right-2
  revision: 4
  author: test
  msg: merge
   A /right-1
   A /right-2
  revision: 3
  author: test
  msg: left-2
   M /b
   A /left-2
  revision: 2
  author: test
  msg: left-1
   M /b
   A /left-1
  revision: 1
  author: test
  msg: base
   A /b

Tags are not supported, but must not break conversion

  $ rm -rf a a-hg a-hg-wc
  $ hg init a
  $ echo a > a/a
  $ hg --cwd a ci -d '0 0' -A -m 'Add file a'
  adding a
  $ hg --cwd a tag -d '1 0' -m 'Tagged as v1.0' v1.0

  $ hg convert -d svn a
  assuming destination a-hg
  initializing svn repository 'a-hg'
  initializing svn working copy 'a-hg-wc'
  scanning source...
  sorting...
  converting...
  1 Add file a
  0 Tagged as v1.0
  writing Subversion tags is not yet implemented
  $ svnupanddisplay a-hg-wc 2
   2 1 test a
   2 2 test .
   2 2 test .hgtags
  revision: 2
  author: test
  msg: Tagged as v1.0
   A /.hgtags
  revision: 1
  author: test
  msg: Add file a
   A /a
  $ rm -rf a a-hg a-hg-wc