tests/test-bundle-vs-outgoing.t

rebase: calculate ancestors for --base separately (issue5420)

Previously, the --base option only works with a single "branch" - if there
is one changeset in the "--base" revset whose branching point(s) is/are
different from another changeset in the "--base" revset, "rebase" will error
out with:

  abort: source is ancestor of destination

This happens if the user has multiple draft branches, and uses "hg rebase -b
'draft()' -d master", for example. The error message looks cryptic to users
who don't know the implementation detail.

This patch changes the logic to calculate the common ancestor for every
"base" changeset separately so we won't (incorrectly) select "source" which
is an ancestor of the destination.

This patch should not change the behavior where all changesets specified by
"--base" have the same branching point(s).

A new situation is: some of the specified changesets could be rebased, while
some couldn't (because they are descendants of the destination, or they do
not share a common ancestor with the destination). The current behavior is
to show "nothing to rebase" and exits with 1.

This patch maintains the current behavior (show "nothing to rebase") even if
part of the "--base" revset could be rebased. A clearer error message may be
"cannot find branching point for X", or "X is a descendant of destination".
The error message issue is tracked by issue5422 separately.

A test is added with all kinds of tricky cases I could think of for now.

this structure seems to tickle a bug in bundle's search for
changesets, so first we have to recreate it

o  8
|
| o  7
| |
| o  6
|/|
o |  5
| |
o |  4
| |
| o  3
| |
| o  2
|/
o  1
|
o  0

  $ mkrev()
  > {
  >     revno=$1
  >     echo "rev $revno"
  >     echo "rev $revno" > foo.txt
  >     hg -q ci -m"rev $revno"
  > }

setup test repo1

  $ hg init repo1
  $ cd repo1
  $ echo "rev 0" > foo.txt
  $ hg ci -Am"rev 0"
  adding foo.txt
  $ mkrev 1
  rev 1

first branch

  $ mkrev 2
  rev 2
  $ mkrev 3
  rev 3

back to rev 1 to create second branch

  $ hg up -r1
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ mkrev 4
  rev 4
  $ mkrev 5
  rev 5

merge first branch to second branch

  $ hg up -C -r5
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ HGMERGE=internal:local hg merge
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ echo "merge rev 5, rev 3" > foo.txt
  $ hg ci -m"merge first branch to second branch"

one more commit following the merge

  $ mkrev 7
  rev 7

back to "second branch" to make another head

  $ hg up -r5
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ mkrev 8
  rev 8

the story so far

  $ hg log -G --template "{rev}\n"
  @  8
  |
  | o  7
  | |
  | o  6
  |/|
  o |  5
  | |
  o |  4
  | |
  | o  3
  | |
  | o  2
  |/
  o  1
  |
  o  0
  

check that "hg outgoing" really does the right thing

sanity check of outgoing: expect revs 4 5 6 7 8

  $ hg clone -r3 . ../repo2
  adding changesets
  adding manifests
  adding file changes
  added 4 changesets with 4 changes to 1 files
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

this should (and does) report 5 outgoing revisions: 4 5 6 7 8

  $ hg outgoing --template "{rev}\n" ../repo2
  comparing with ../repo2
  searching for changes
  4
  5
  6
  7
  8

test bundle (destination repo): expect 5 revisions

this should bundle the same 5 revisions that outgoing reported, but it

actually bundles 7

  $ hg bundle foo.bundle ../repo2
  searching for changes
  5 changesets found

test bundle (base revision): expect 5 revisions

this should (and does) give exactly the same result as bundle

with a destination repo... i.e. it's wrong too

  $ hg bundle --base 3 foo.bundle
  5 changesets found

  $ cd ..