view tests/test-confused-revert.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.

  $ hg init repo
  $ cd repo
  $ echo foo > a
  $ hg add a
  $ hg commit -m "1"

  $ echo bar > b
  $ hg add b
  $ hg remove a

Should show a removed and b added:

  $ hg status
  A b
  R a

  $ hg revert --all
  forgetting b
  undeleting a

Should show b unknown and a back to normal:

  $ hg status
  ? b

  $ rm b

  $ hg co -C 0
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo foo-a > a
  $ hg commit -m "2a"

  $ hg co -C 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo foo-b > a
  $ hg commit -m "2b"
  created new head

  $ HGMERGE=true hg merge 1
  merging a
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

Should show foo-b:

  $ cat a
  foo-b

  $ echo bar > b
  $ hg add b
  $ rm a
  $ hg remove a

Should show a removed and b added:

  $ hg status
  A b
  R a

Revert should fail:

  $ hg revert
  abort: uncommitted merge with no revision specified
  (use 'hg update' or see 'hg help revert')
  [10]

Revert should be ok now:

  $ hg revert -r2 --all
  forgetting b
  undeleting a

Should show b unknown and a marked modified (merged):

  $ hg status
  M a
  ? b

Should show foo-b:

  $ cat a
  foo-b