view tests/test-convert-svn-tags.t @ 14007:d764463b433e

atomictempfile: avoid infinite recursion in __del__().

The problem is that a programmer using atomictempfile directly can
make an innocent everyday mistake -- not enough args to the
constructor -- which escalates badly.  You would expect a simple
TypeError crash in that case, but you actually get an infinite
recursion that is surprisingly difficult to kill: it happens between
__del__() and __getattr__(), and Python does not handle infinite
recursion from __del__() well.

The fix is to not implement __getattr__(), but instead assign instance
attributes for the methods we wish to delegate to the builtin file
type: write() and fileno(). I've audited mercurial.* and hgext.* and
found no users of atomictempfile using methods other than write() and
rename(). I audited third-party extensions and found one (snap)
passing an atomictempfile to util.fstat(), so I also threw in
fileno().

The last time I submitted a similar patch, Matt proposed that we make
atomictempfile a subclass of file instead of wrapping it. Rejected on
grounds of unnecessary complexity: for one thing, it would make the
Windows implementation of posixfile quite a bit more complex. It would
have to become a subclass of file rather than a simple function -- but
since it's written in C, this is non-obvious and non-trivial.
Furthermore, there's nothing wrong with wrapping objects and
delegating methods: it's a well-established pattern that works just
fine in many cases. Subclassing is not the answer to all of life's
problems.

  $ "$TESTDIR/hghave" svn svn-bindings || exit 80

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

  $ svnadmin create svn-repo
  $ svnadmin load -q svn-repo < "$TESTDIR/svn/tags.svndump"

Convert
  $ hg convert --datesort svn-repo A-hg
  initializing destination A-hg repository
  scanning source...
  sorting...
  converting...
  5 init projA
  4 adda
  3 changea
  2 changea2
  1 changea3
  0 changea
  updating tags

  $ cd A-hg
  $ hg glog --template '{rev} {desc|firstline} tags: {tags}\n'
  o  6 update tags tags: tip
  |
  o  5 changea tags: trunk.goodtag
  |
  o  4 changea3 tags:
  |
  o  3 changea2 tags: trunk.v1
  |
  o  2 changea tags:
  |
  o  1 adda tags:
  |
  o  0 init projA tags:
  

  $ hg tags -q
  tip
  trunk.goodtag
  trunk.v1

  $ cd ..

Convert without tags

  $ hg convert --datesort --config convert.svn.tags= svn-repo A-notags-hg
  initializing destination A-notags-hg repository
  scanning source...
  sorting...
  converting...
  5 init projA
  4 adda
  3 changea
  2 changea2
  1 changea3
  0 changea

  $ hg -R A-notags-hg tags -q
  tip