--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/test-graft-rename.t Fri Dec 27 15:53:16 2019 -0800
@@ -0,0 +1,733 @@
+
+Graft from behind a move or rename
+==================================
+
+NOTE: This is affected by issue5343, and will need updating when it's fixed
+
+Consider this topology for a regular graft:
+
+o c1
+|
+| o c2
+| |
+| o ca # stands for "common ancestor"
+|/
+o cta # stands for "common topological ancestor"
+
+Note that in issue5343, ca==cta.
+
+The following table shows the possible cases. Here, "x->y" and, equivalently,
+"y<-x", where x is an ancestor of y, means that some copy happened from x to y.
+
+name | c1<-cta | cta<->ca | ca->c2
+A.0 | | |
+A.1 | X | |
+A.2 | | X |
+A.3 | | | X
+A.4 | X | X |
+A.5 | X | | X
+A.6 | | X | X
+A.7 | X | X | X
+
+A.0 is trivial, and doesn't need copy tracking.
+For A.1, a forward rename is recorded in the c1 pass, to be followed later.
+In A.2, the rename is recorded in the c2 pass and followed backwards.
+A.3 is recorded in the c2 pass as a forward rename to be duplicated on target.
+In A.4, both passes of checkcopies record incomplete renames, which are
+then joined in mergecopies to record a rename to be followed.
+In A.5 and A.7, the c1 pass records an incomplete rename, while the c2 pass
+records an incomplete divergence. The incomplete rename is then joined to the
+appropriate side of the incomplete divergence, and the result is recorded as a
+divergence. The code doesn't distinguish at all between these two cases, since
+the end result of them is the same: an incomplete divergence joined with an
+incomplete rename into a divergence.
+Finally, A.6 records a divergence entirely in the c2 pass.
+
+A.4 has a degenerate case a<-b<-a->a, where checkcopies isn't needed at all.
+A.5 has a special case a<-b<-b->a, which is treated like a<-b->a in a merge.
+A.5 has issue5343 as a special case.
+A.6 has a special case a<-a<-b->a. Here, checkcopies will find a spurious
+incomplete divergence, which is in fact complete. This is handled later in
+mergecopies.
+A.7 has 4 special cases: a<-b<-a->b (the "ping-pong" case), a<-b<-c->b,
+a<-b<-a->c and a<-b<-c->a. Of these, only the "ping-pong" case is interesting,
+the others are fairly trivial (a<-b<-c->b and a<-b<-a->c proceed like the base
+case, a<-b<-c->a is treated the same as a<-b<-b->a).
+
+f5a therefore tests the "ping-pong" rename case, where a file is renamed to the
+same name on both branches, then the rename is backed out on one branch, and
+the backout is grafted to the other branch. This creates a challenging rename
+sequence of a<-b<-a->b in the graft target, topological CA, graft CA and graft
+source, respectively. Since rename detection will run on the c1 side for such a
+sequence (as for technical reasons, we split the c1 and c2 sides not at the
+graft CA, but rather at the topological CA), it will pick up a false rename,
+and cause a spurious merge conflict. This false rename is always exactly the
+reverse of the true rename that would be detected on the c2 side, so we can
+correct for it by detecting this condition and reversing as necessary.
+
+First, set up the repository with commits to be grafted
+
+ $ hg init graftmove
+ $ cd graftmove
+ $ echo c1a > f1a
+ $ echo c2a > f2a
+ $ echo c3a > f3a
+ $ echo c4a > f4a
+ $ echo c5a > f5a
+ $ hg ci -qAm A0
+ $ hg mv f1a f1b
+ $ hg mv f3a f3b
+ $ hg mv f5a f5b
+ $ hg ci -qAm B0
+ $ echo c1c > f1b
+ $ hg mv f2a f2c
+ $ hg mv f5b f5a
+ $ echo c5c > f5a
+ $ hg ci -qAm C0
+ $ hg mv f3b f3d
+ $ echo c4d > f4a
+ $ hg ci -qAm D0
+ $ hg log -G
+ @ changeset: 3:b69f5839d2d9
+ | tag: tip
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | summary: D0
+ |
+ o changeset: 2:f58c7e2b28fa
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | summary: C0
+ |
+ o changeset: 1:3d7bba921b5d
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | summary: B0
+ |
+ o changeset: 0:11f7a1b56675
+ user: test
+ date: Thu Jan 01 00:00:00 1970 +0000
+ summary: A0
+
+
+Test the cases A.2 (f1x), A.3 (f2x) and a special case of A.6 (f5x) where the
+two renames actually converge to the same name (thus no actual divergence).
+
+ $ hg up -q 'desc("A0")'
+ $ HGEDITOR="echo C1 >" hg graft -r 'desc("C0")' --edit
+ grafting 2:f58c7e2b28fa "C0"
+ merging f1a and f1b to f1a
+ merging f5a
+ warning: can't find ancestor for 'f5a' copied from 'f5b'!
+ $ hg status --change .
+ M f1a
+ M f5a
+ A f2c
+ R f2a
+ $ hg cat f1a
+ c1c
+ $ hg cat f1b
+ f1b: no such file in rev c9763722f9bd
+ [1]
+
+Test the cases A.0 (f4x) and A.6 (f3x)
+
+ $ HGEDITOR="echo D1 >" hg graft -r 'desc("D0")' --edit
+ grafting 3:b69f5839d2d9 "D0"
+ note: possible conflict - f3b was renamed multiple times to:
+ f3a
+ f3d
+ warning: can't find ancestor for 'f3d' copied from 'f3b'!
+
+Set up the repository for some further tests
+
+ $ hg up -q "min(desc("A0"))"
+ $ hg mv f1a f1e
+ $ echo c2e > f2a
+ $ hg mv f3a f3e
+ $ hg mv f4a f4e
+ $ hg mv f5a f5b
+ $ hg ci -qAm "E0"
+ $ hg up -q "min(desc("A0"))"
+ $ hg cp f1a f1f
+ $ hg ci -qAm "F0"
+ $ hg up -q "min(desc("A0"))"
+ $ hg cp f1a f1g
+ $ echo c1g > f1g
+ $ hg ci -qAm "G0"
+ $ hg log -G
+ @ changeset: 8:ba67f08fb15a
+ | tag: tip
+ | parent: 0:11f7a1b56675
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | summary: G0
+ |
+ | o changeset: 7:d376ab0d7fda
+ |/ parent: 0:11f7a1b56675
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | summary: F0
+ |
+ | o changeset: 6:6bd1736cab86
+ |/ parent: 0:11f7a1b56675
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | summary: E0
+ |
+ | o changeset: 5:560daee679da
+ | | user: test
+ | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | summary: D1
+ | |
+ | o changeset: 4:c9763722f9bd
+ |/ parent: 0:11f7a1b56675
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | summary: C1
+ |
+ | o changeset: 3:b69f5839d2d9
+ | | user: test
+ | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | summary: D0
+ | |
+ | o changeset: 2:f58c7e2b28fa
+ | | user: test
+ | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | summary: C0
+ | |
+ | o changeset: 1:3d7bba921b5d
+ |/ user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | summary: B0
+ |
+ o changeset: 0:11f7a1b56675
+ user: test
+ date: Thu Jan 01 00:00:00 1970 +0000
+ summary: A0
+
+
+Test the cases A.4 (f1x), the "ping-pong" special case of A.7 (f5x),
+and A.3 with a local content change to be preserved (f2x).
+
+ $ hg up -q "desc("E0")"
+ $ HGEDITOR="echo C2 >" hg graft -r 'desc("C0")' --edit
+ grafting 2:f58c7e2b28fa "C0"
+ merging f1e and f1b to f1e
+ merging f2a and f2c to f2c
+
+Test the cases A.1 (f4x) and A.7 (f3x).
+
+ $ HGEDITOR="echo D2 >" hg graft -r 'desc("D0")' --edit
+ grafting 3:b69f5839d2d9 "D0"
+ note: possible conflict - f3b was renamed multiple times to:
+ f3d
+ f3e
+ merging f4e and f4a to f4e
+ warning: can't find ancestor for 'f3d' copied from 'f3b'!
+
+ $ hg cat f2c
+ c2e
+
+Test the case A.5 (move case, f1x).
+
+ $ hg up -q "desc("C0")"
+BROKEN: Shouldn't get the warning about missing ancestor
+ $ HGEDITOR="echo E1 >" hg graft -r 'desc("E0")' --edit
+ grafting 6:6bd1736cab86 "E0"
+ note: possible conflict - f1a was renamed multiple times to:
+ f1b
+ f1e
+ note: possible conflict - f3a was renamed multiple times to:
+ f3b
+ f3e
+ merging f2c and f2a to f2c
+ merging f5a and f5b to f5b
+ warning: can't find ancestor for 'f1e' copied from 'f1a'!
+ warning: can't find ancestor for 'f3e' copied from 'f3a'!
+ $ cat f1e
+ c1a
+
+Test the case A.5 (copy case, f1x).
+
+ $ hg up -q "desc("C0")"
+BROKEN: Shouldn't get the warning about missing ancestor
+ $ HGEDITOR="echo F1 >" hg graft -r 'desc("F0")' --edit
+ grafting 7:d376ab0d7fda "F0"
+ warning: can't find ancestor for 'f1f' copied from 'f1a'!
+BROKEN: f1f should be marked a copy from f1b
+ $ hg st --copies --change .
+ A f1f
+BROKEN: f1f should have the new content from f1b (i.e. "c1c")
+ $ cat f1f
+ c1a
+
+Test the case A.5 (copy+modify case, f1x).
+
+ $ hg up -q "desc("C0")"
+BROKEN: We should get a merge conflict from the 3-way merge between f1b in C0
+(content "c1c") and f1g in G0 (content "c1g") with f1a in A0 as base (content
+"c1a")
+ $ HGEDITOR="echo G1 >" hg graft -r 'desc("G0")' --edit
+ grafting 8:ba67f08fb15a "G0"
+ warning: can't find ancestor for 'f1g' copied from 'f1a'!
+
+Check the results of the grafts tested
+
+ $ hg log -CGv --patch --git
+ @ changeset: 13:ef3adf6c20a4
+ | tag: tip
+ | parent: 2:f58c7e2b28fa
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | files: f1g
+ | description:
+ | G1
+ |
+ |
+ | diff --git a/f1g b/f1g
+ | new file mode 100644
+ | --- /dev/null
+ | +++ b/f1g
+ | @@ -0,0 +1,1 @@
+ | +c1g
+ |
+ | o changeset: 12:b5542d755b54
+ |/ parent: 2:f58c7e2b28fa
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | files: f1f
+ | description:
+ | F1
+ |
+ |
+ | diff --git a/f1f b/f1f
+ | new file mode 100644
+ | --- /dev/null
+ | +++ b/f1f
+ | @@ -0,0 +1,1 @@
+ | +c1a
+ |
+ | o changeset: 11:f8a162271246
+ |/ parent: 2:f58c7e2b28fa
+ | user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | files: f1e f2c f3e f4a f4e f5a f5b
+ | copies: f4e (f4a) f5b (f5a)
+ | description:
+ | E1
+ |
+ |
+ | diff --git a/f1e b/f1e
+ | new file mode 100644
+ | --- /dev/null
+ | +++ b/f1e
+ | @@ -0,0 +1,1 @@
+ | +c1a
+ | diff --git a/f2c b/f2c
+ | --- a/f2c
+ | +++ b/f2c
+ | @@ -1,1 +1,1 @@
+ | -c2a
+ | +c2e
+ | diff --git a/f3e b/f3e
+ | new file mode 100644
+ | --- /dev/null
+ | +++ b/f3e
+ | @@ -0,0 +1,1 @@
+ | +c3a
+ | diff --git a/f4a b/f4e
+ | rename from f4a
+ | rename to f4e
+ | diff --git a/f5a b/f5b
+ | rename from f5a
+ | rename to f5b
+ |
+ | o changeset: 10:93ee502e8b0a
+ | | user: test
+ | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | files: f3d f4e
+ | | description:
+ | | D2
+ | |
+ | |
+ | | diff --git a/f3d b/f3d
+ | | new file mode 100644
+ | | --- /dev/null
+ | | +++ b/f3d
+ | | @@ -0,0 +1,1 @@
+ | | +c3a
+ | | diff --git a/f4e b/f4e
+ | | --- a/f4e
+ | | +++ b/f4e
+ | | @@ -1,1 +1,1 @@
+ | | -c4a
+ | | +c4d
+ | |
+ | o changeset: 9:539cf145f496
+ | | parent: 6:6bd1736cab86
+ | | user: test
+ | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | files: f1e f2a f2c f5a f5b
+ | | copies: f2c (f2a) f5a (f5b)
+ | | description:
+ | | C2
+ | |
+ | |
+ | | diff --git a/f1e b/f1e
+ | | --- a/f1e
+ | | +++ b/f1e
+ | | @@ -1,1 +1,1 @@
+ | | -c1a
+ | | +c1c
+ | | diff --git a/f2a b/f2c
+ | | rename from f2a
+ | | rename to f2c
+ | | diff --git a/f5b b/f5a
+ | | rename from f5b
+ | | rename to f5a
+ | | --- a/f5b
+ | | +++ b/f5a
+ | | @@ -1,1 +1,1 @@
+ | | -c5a
+ | | +c5c
+ | |
+ | | o changeset: 8:ba67f08fb15a
+ | | | parent: 0:11f7a1b56675
+ | | | user: test
+ | | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | | files: f1g
+ | | | copies: f1g (f1a)
+ | | | description:
+ | | | G0
+ | | |
+ | | |
+ | | | diff --git a/f1a b/f1g
+ | | | copy from f1a
+ | | | copy to f1g
+ | | | --- a/f1a
+ | | | +++ b/f1g
+ | | | @@ -1,1 +1,1 @@
+ | | | -c1a
+ | | | +c1g
+ | | |
+ | | | o changeset: 7:d376ab0d7fda
+ | | |/ parent: 0:11f7a1b56675
+ | | | user: test
+ | | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | | files: f1f
+ | | | copies: f1f (f1a)
+ | | | description:
+ | | | F0
+ | | |
+ | | |
+ | | | diff --git a/f1a b/f1f
+ | | | copy from f1a
+ | | | copy to f1f
+ | | |
+ | o | changeset: 6:6bd1736cab86
+ | |/ parent: 0:11f7a1b56675
+ | | user: test
+ | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | files: f1a f1e f2a f3a f3e f4a f4e f5a f5b
+ | | copies: f1e (f1a) f3e (f3a) f4e (f4a) f5b (f5a)
+ | | description:
+ | | E0
+ | |
+ | |
+ | | diff --git a/f1a b/f1e
+ | | rename from f1a
+ | | rename to f1e
+ | | diff --git a/f2a b/f2a
+ | | --- a/f2a
+ | | +++ b/f2a
+ | | @@ -1,1 +1,1 @@
+ | | -c2a
+ | | +c2e
+ | | diff --git a/f3a b/f3e
+ | | rename from f3a
+ | | rename to f3e
+ | | diff --git a/f4a b/f4e
+ | | rename from f4a
+ | | rename to f4e
+ | | diff --git a/f5a b/f5b
+ | | rename from f5a
+ | | rename to f5b
+ | |
+ | | o changeset: 5:560daee679da
+ | | | user: test
+ | | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | | files: f3d f4a
+ | | | description:
+ | | | D1
+ | | |
+ | | |
+ | | | diff --git a/f3d b/f3d
+ | | | new file mode 100644
+ | | | --- /dev/null
+ | | | +++ b/f3d
+ | | | @@ -0,0 +1,1 @@
+ | | | +c3a
+ | | | diff --git a/f4a b/f4a
+ | | | --- a/f4a
+ | | | +++ b/f4a
+ | | | @@ -1,1 +1,1 @@
+ | | | -c4a
+ | | | +c4d
+ | | |
+ | | o changeset: 4:c9763722f9bd
+ | |/ parent: 0:11f7a1b56675
+ | | user: test
+ | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | files: f1a f2a f2c f5a
+ | | copies: f2c (f2a)
+ | | description:
+ | | C1
+ | |
+ | |
+ | | diff --git a/f1a b/f1a
+ | | --- a/f1a
+ | | +++ b/f1a
+ | | @@ -1,1 +1,1 @@
+ | | -c1a
+ | | +c1c
+ | | diff --git a/f2a b/f2c
+ | | rename from f2a
+ | | rename to f2c
+ | | diff --git a/f5a b/f5a
+ | | --- a/f5a
+ | | +++ b/f5a
+ | | @@ -1,1 +1,1 @@
+ | | -c5a
+ | | +c5c
+ | |
+ +---o changeset: 3:b69f5839d2d9
+ | | user: test
+ | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | files: f3b f3d f4a
+ | | copies: f3d (f3b)
+ | | description:
+ | | D0
+ | |
+ | |
+ | | diff --git a/f3b b/f3d
+ | | rename from f3b
+ | | rename to f3d
+ | | diff --git a/f4a b/f4a
+ | | --- a/f4a
+ | | +++ b/f4a
+ | | @@ -1,1 +1,1 @@
+ | | -c4a
+ | | +c4d
+ | |
+ o | changeset: 2:f58c7e2b28fa
+ | | user: test
+ | | date: Thu Jan 01 00:00:00 1970 +0000
+ | | files: f1b f2a f2c f5a f5b
+ | | copies: f2c (f2a) f5a (f5b)
+ | | description:
+ | | C0
+ | |
+ | |
+ | | diff --git a/f1b b/f1b
+ | | --- a/f1b
+ | | +++ b/f1b
+ | | @@ -1,1 +1,1 @@
+ | | -c1a
+ | | +c1c
+ | | diff --git a/f2a b/f2c
+ | | rename from f2a
+ | | rename to f2c
+ | | diff --git a/f5b b/f5a
+ | | rename from f5b
+ | | rename to f5a
+ | | --- a/f5b
+ | | +++ b/f5a
+ | | @@ -1,1 +1,1 @@
+ | | -c5a
+ | | +c5c
+ | |
+ o | changeset: 1:3d7bba921b5d
+ |/ user: test
+ | date: Thu Jan 01 00:00:00 1970 +0000
+ | files: f1a f1b f3a f3b f5a f5b
+ | copies: f1b (f1a) f3b (f3a) f5b (f5a)
+ | description:
+ | B0
+ |
+ |
+ | diff --git a/f1a b/f1b
+ | rename from f1a
+ | rename to f1b
+ | diff --git a/f3a b/f3b
+ | rename from f3a
+ | rename to f3b
+ | diff --git a/f5a b/f5b
+ | rename from f5a
+ | rename to f5b
+ |
+ o changeset: 0:11f7a1b56675
+ user: test
+ date: Thu Jan 01 00:00:00 1970 +0000
+ files: f1a f2a f3a f4a f5a
+ description:
+ A0
+
+
+ diff --git a/f1a b/f1a
+ new file mode 100644
+ --- /dev/null
+ +++ b/f1a
+ @@ -0,0 +1,1 @@
+ +c1a
+ diff --git a/f2a b/f2a
+ new file mode 100644
+ --- /dev/null
+ +++ b/f2a
+ @@ -0,0 +1,1 @@
+ +c2a
+ diff --git a/f3a b/f3a
+ new file mode 100644
+ --- /dev/null
+ +++ b/f3a
+ @@ -0,0 +1,1 @@
+ +c3a
+ diff --git a/f4a b/f4a
+ new file mode 100644
+ --- /dev/null
+ +++ b/f4a
+ @@ -0,0 +1,1 @@
+ +c4a
+ diff --git a/f5a b/f5a
+ new file mode 100644
+ --- /dev/null
+ +++ b/f5a
+ @@ -0,0 +1,1 @@
+ +c5a
+
+Check superfluous filemerge of files renamed in the past but untouched by graft
+
+ $ echo a > a
+ $ hg ci -qAma
+ $ hg mv a b
+ $ echo b > b
+ $ hg ci -qAmb
+ $ echo c > c
+ $ hg ci -qAmc
+ $ hg up -q .~2
+ $ hg graft tip -qt:fail
+
+ $ cd ..
+
+Graft a change into a new file previously grafted into a renamed directory
+
+ $ hg init dirmovenewfile
+ $ cd dirmovenewfile
+ $ mkdir a
+ $ echo a > a/a
+ $ hg ci -qAma
+ $ echo x > a/x
+ $ hg ci -qAmx
+ $ hg up -q 0
+ $ hg mv -q a b
+ $ hg ci -qAmb
+ $ hg graft -q 1 # a/x grafted as b/x, but no copy information recorded
+ $ hg up -q 1
+ $ echo y > a/x
+ $ hg ci -qAmy
+ $ hg up -q 3
+ $ hg graft -q 4
+ $ hg status --change .
+ M b/x
+
+Prepare for test of skipped changesets and how merges can influence it:
+
+ $ hg merge -q -r 1 --tool :local
+ $ hg ci -m m
+ $ echo xx >> b/x
+ $ hg ci -m xx
+
+ $ hg log -G -T '{rev} {desc|firstline}'
+ @ 7 xx
+ |
+ o 6 m
+ |\
+ | o 5 y
+ | |
+ +---o 4 y
+ | |
+ | o 3 x
+ | |
+ | o 2 b
+ | |
+ o | 1 x
+ |/
+ o 0 a
+
+Grafting of plain changes correctly detects that 3 and 5 should be skipped:
+
+ $ hg up -qCr 4
+ $ hg graft --tool :local -r 2::5
+ skipping already grafted revision 3:ca093ca2f1d9 (was grafted from 1:13ec5badbf2a)
+ skipping already grafted revision 5:43e9eb70dab0 (was grafted from 4:6c9a1289e5f1)
+ grafting 2:42127f193bcd "b"
+
+Extending the graft range to include a (skipped) merge of 3 will not prevent us from
+also detecting that both 3 and 5 should be skipped:
+
+ $ hg up -qCr 4
+ $ hg graft --tool :local -r 2::7
+ skipping ungraftable merge revision 6
+ skipping already grafted revision 3:ca093ca2f1d9 (was grafted from 1:13ec5badbf2a)
+ skipping already grafted revision 5:43e9eb70dab0 (was grafted from 4:6c9a1289e5f1)
+ grafting 2:42127f193bcd "b"
+ grafting 7:d3c3f2b38ecc "xx"
+ note: graft of 7:d3c3f2b38ecc created no changes to commit
+
+ $ cd ..
+
+Grafted revision should be warned and skipped only once. (issue6024)
+
+ $ mkdir issue6024
+ $ cd issue6024
+
+ $ hg init base
+ $ cd base
+ $ touch x
+ $ hg commit -qAminit
+ $ echo a > x
+ $ hg commit -mchange
+ $ hg update -q 0
+ $ hg graft -r 1
+ grafting 1:a0b923c546aa "change" (tip)
+ $ cd ..
+
+ $ hg clone -qr 2 base clone
+ $ cd clone
+ $ hg pull -q
+ $ hg merge -q 2
+ $ hg commit -mmerge
+ $ hg update -q 0
+ $ hg graft -r 1
+ grafting 1:04fc6d444368 "change"
+ $ hg update -q 3
+ $ hg log -G -T '{rev}:{node|shortest} <- {extras.source|shortest}\n'
+ o 4:4e16 <- a0b9
+ |
+ | @ 3:f0ac <-
+ | |\
+ +---o 2:a0b9 <-
+ | |
+ | o 1:04fc <- a0b9
+ |/
+ o 0:7848 <-
+
+
+ the source of rev 4 is an ancestor of the working parent, and was also
+ grafted as rev 1. it should be stripped from the target revisions only once.
+
+ $ hg graft -r 4
+ skipping already grafted revision 4:4e16bab40c9c (1:04fc6d444368 also has origin 2:a0b923c546aa)
+ [255]
+
+ $ cd ../..