view tests/test-no-symlinks.t @ 50741:bca4037306da stable

rust-revlog: fix incorrect results with NULL_NODE prefixes

In case a short hash is a prefix of `NULL_NODE`, the correct revision
number lookup is `NULL_REVISION` only if there is no match in the nodemap.
Indeed, if there is a single nodemap match, then it is an ambiguity with the
always matching `NULL_NODE`.

Before this change, using the Mercurial development repository as a testbed (it
has public changesets with node ID starting with `0005` and `0009`), this is
what `rhg` did (plain `hg` provided for reference)

```
$ rust/target/debug/rhg cat -r 000 README
README: no such file in rev 000000000000
$ hg cat -r 000 README
abort: ambiguous revision identifier: 000
```

Here is the expected output for `rhg` on ambiguous prefixes (again, before
this change):

```
$ rust/target/debug/rhg cat -r 0001 README
abort: ambiguous revision identifier: 0001
```

The test provided by 8c29af0f6d6e in `test-rhg.t` could become flaky with
this change, unless all hashes are fixed. We expect reviewers to be more
sure about that than we are.

#require no-symlink

# The following script was used to create the bundle:
#
# hg init symlinks
# cd symlinks
# echo a > a
# mkdir d
# echo b > d/b
# ln -s a a.lnk
# ln -s d/b d/b.lnk
# hg ci -Am t
# hg bundle --base null ../test-no-symlinks.hg

Extract a symlink on a platform not supporting them

  $ hg init t
  $ cd t
  $ hg pull -q "$TESTDIR/bundles/test-no-symlinks.hg"
  $ hg update
  4 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat a.lnk && echo
  a
  $ cat d/b.lnk && echo
  d/b

Copy a symlink and move another

  $ hg copy a.lnk d/a2.lnk
  $ hg mv d/b.lnk b2.lnk
  $ hg ci -Am copy
  $ cat d/a2.lnk && echo
  a
  $ cat b2.lnk && echo
  d/b

Bundle and extract again

  $ hg bundle --base null ../symlinks.hg
  2 changesets found
  $ cd ..
  $ hg init t2
  $ cd t2
  $ hg pull ../symlinks.hg
  pulling from ../symlinks.hg
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 6 changes to 6 files
  new changesets d326ae2d01ee:71d85cf3ba90 (2 drafts)
  (run 'hg update' to get a working copy)
  $ hg update
  5 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat a.lnk && echo
  a
  $ cat d/a2.lnk && echo
  a
  $ cat b2.lnk && echo
  d/b