tests/test-hardlinks.t

check-code: catch Python 'is' comparing number or string literals

The Python 'is' operator compares object identity, so it should
definitely not be applied to string or number literals, which Python
implementations are free to represent with a temporary object.

This should catch the following kinds of bogus expressions (examples):

  x is 'foo'     x is not 'foo'
  x is "bar"     x is not "bar"
  x is 42        x is not 42
  x is -36       x is not -36

As originally proposed by Martin Geisler, amended with catching
negative numbers.

  $ cat > nlinks.py <<EOF
  > import os, sys
  > for f in sorted(sys.stdin.readlines()):
  >     f = f[:-1]
  >     print os.lstat(f).st_nlink, f
  > EOF

  $ nlinksdir()
  > {
  >     find $1 -type f | python $TESTTMP/nlinks.py
  > }

Some implementations of cp can't create hardlinks (replaces 'cp -al' on Linux):

  $ cat > linkcp.py <<EOF
  > from mercurial import util
  > import sys
  > util.copyfiles(sys.argv[1], sys.argv[2], hardlink=True)
  > EOF

  $ linkcp()
  > {
  >     python $TESTTMP/linkcp.py $1 $2
  > }

Prepare repo r1:

  $ mkdir r1
  $ cd r1
  $ hg init

  $ echo c1 > f1
  $ hg add f1
  $ hg ci -m0

  $ mkdir d1
  $ cd d1
  $ echo c2 > f2
  $ hg add f2
  $ hg ci -m1
  $ cd ../..

  $ nlinksdir r1/.hg/store
  1 r1/.hg/store/00changelog.i
  1 r1/.hg/store/00manifest.i
  1 r1/.hg/store/data/d1/f2.i
  1 r1/.hg/store/data/f1.i
  1 r1/.hg/store/fncache
  1 r1/.hg/store/undo


Create hardlinked clone r2:

  $ hg clone -U --debug r1 r2
  linked 7 files

Create non-hardlinked clone r3:

  $ hg clone --pull r1 r3
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved


Repos r1 and r2 should now contain hardlinked files:

  $ nlinksdir r1/.hg/store
  2 r1/.hg/store/00changelog.i
  2 r1/.hg/store/00manifest.i
  2 r1/.hg/store/data/d1/f2.i
  2 r1/.hg/store/data/f1.i
  2 r1/.hg/store/fncache
  1 r1/.hg/store/undo

  $ nlinksdir r2/.hg/store
  2 r2/.hg/store/00changelog.i
  2 r2/.hg/store/00manifest.i
  2 r2/.hg/store/data/d1/f2.i
  2 r2/.hg/store/data/f1.i
  2 r2/.hg/store/fncache

Repo r3 should not be hardlinked:

  $ nlinksdir r3/.hg/store
  1 r3/.hg/store/00changelog.i
  1 r3/.hg/store/00manifest.i
  1 r3/.hg/store/data/d1/f2.i
  1 r3/.hg/store/data/f1.i
  1 r3/.hg/store/fncache
  1 r3/.hg/store/undo


Create a non-inlined filelog in r3:

  $ cd r3/d1
  $ python -c 'for x in range(10000): print x' >> data1
  $ for j in 0 1 2 3 4 5 6 7 8 9; do
  >   cat data1 >> f2
  >   hg commit -m$j
  > done
  $ cd ../..

  $ nlinksdir r3/.hg/store
  1 r3/.hg/store/00changelog.i
  1 r3/.hg/store/00manifest.i
  1 r3/.hg/store/data/d1/f2.d
  1 r3/.hg/store/data/d1/f2.i
  1 r3/.hg/store/data/f1.i
  1 r3/.hg/store/fncache
  1 r3/.hg/store/undo

Push to repo r1 should break up most hardlinks in r2:

  $ hg -R r2 verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  2 files, 2 changesets, 2 total revisions

  $ cd r3
  $ hg push
  pushing to $TESTTMP/r1
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 10 changesets with 10 changes to 1 files

  $ cd ..

  $ nlinksdir r2/.hg/store
  1 r2/.hg/store/00changelog.i
  1 r2/.hg/store/00manifest.i
  1 r2/.hg/store/data/d1/f2.i
  2 r2/.hg/store/data/f1.i
  1 r2/.hg/store/fncache

  $ hg -R r2 verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  2 files, 2 changesets, 2 total revisions


  $ cd r1
  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

Committing a change to f1 in r1 must break up hardlink f1.i in r2:

  $ echo c1c1 >> f1
  $ hg ci -m00
  $ cd ..

  $ nlinksdir r2/.hg/store
  1 r2/.hg/store/00changelog.i
  1 r2/.hg/store/00manifest.i
  1 r2/.hg/store/data/d1/f2.i
  1 r2/.hg/store/data/f1.i
  1 r2/.hg/store/fncache


  $ cd r3
  $ hg tip --template '{rev}:{node|short}\n'
  11:a6451b6bc41f
  $ echo bla > f1
  $ hg ci -m1
  $ cd ..

Create hardlinked copy r4 of r3 (on Linux, we would call 'cp -al'):

  $ linkcp r3 r4

r4 has hardlinks in the working dir (not just inside .hg):

  $ nlinksdir r4
  2 r4/.hg/00changelog.i
  2 r4/.hg/branch
  2 r4/.hg/branchheads.cache
  2 r4/.hg/dirstate
  2 r4/.hg/hgrc
  2 r4/.hg/last-message.txt
  2 r4/.hg/requires
  2 r4/.hg/store/00changelog.i
  2 r4/.hg/store/00manifest.i
  2 r4/.hg/store/data/d1/f2.d
  2 r4/.hg/store/data/d1/f2.i
  2 r4/.hg/store/data/f1.i
  2 r4/.hg/store/fncache
  2 r4/.hg/store/undo
  2 r4/.hg/tags.cache
  2 r4/.hg/undo.branch
  2 r4/.hg/undo.desc
  2 r4/.hg/undo.dirstate
  2 r4/d1/data1
  2 r4/d1/f2
  2 r4/f1

Update back to revision 11 in r4 should break hardlink of file f1:

  $ hg -R r4 up 11
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ nlinksdir r4
  2 r4/.hg/00changelog.i
  1 r4/.hg/branch
  2 r4/.hg/branchheads.cache
  1 r4/.hg/dirstate
  2 r4/.hg/hgrc
  2 r4/.hg/last-message.txt
  2 r4/.hg/requires
  2 r4/.hg/store/00changelog.i
  2 r4/.hg/store/00manifest.i
  2 r4/.hg/store/data/d1/f2.d
  2 r4/.hg/store/data/d1/f2.i
  2 r4/.hg/store/data/f1.i
  2 r4/.hg/store/fncache
  2 r4/.hg/store/undo
  2 r4/.hg/tags.cache
  2 r4/.hg/undo.branch
  2 r4/.hg/undo.desc
  2 r4/.hg/undo.dirstate
  2 r4/d1/data1
  2 r4/d1/f2
  1 r4/f1