view tests/test-rebase-base-flag.t @ 36975:795eb53f1d3e

rebase: allow in-memory merge of the working copy parent

Before this patch and when the rebase involved the working copy parent
(and thus the working copy too), we would not do in-memory rebase even
if requested to. The in-code comment explains that the reason had
something to do with avoiding an extra update, but I don't know which
update that refers to. Perhaps an earlier version of the code used to
update to the destination before rebasing even if in-memory rebase was
requested? That seems to not be done at least since aa660c1203a9
(rebase: do not bail on uncomitted changes if rebasing in-memory,
2017-12-07).

To see if this still made it slower, I create a single tiny commit on
top of one branch of the mozilla-unified repo (commit a1098c82 to be
exact) and rebased it to another branch (commit d4e9a7be). Before this
patch that took 11.8s and after this patch it took 8.6s (I only did
two runs each, but the timings were very consistent).

Differential Revision: https://phab.mercurial-scm.org/D2876

Test the "--base" flag of the rebase command. (Tests unrelated to the "--base"
flag should probably live in somewhere else)

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > rebase=
  > drawdag=$TESTDIR/drawdag.py
  > 
  > [phases]
  > publish=False
  > 
  > [alias]
  > tglog = log -G --template "{rev}: {node|short} {desc}"
  > EOF

  $ rebasewithdag() {
  >   N=`$PYTHON -c "print($N+1)"`
  >   hg init repo$N && cd repo$N
  >   hg debugdrawdag
  >   hg rebase "$@" > _rebasetmp
  >   r=$?
  >   grep -v 'saved backup bundle' _rebasetmp
  >   [ $r -eq 0 ] && hg tglog
  >   cd ..
  >   return $r
  > }

Single branching point, without merge:

  $ rebasewithdag -b D -d Z <<'EOS'
  >     D E
  >     |/
  > Z B C   # C: branching point, E should be picked
  >  \|/    # B should not be picked
  >   A
  >   |
  >   R
  > EOS
  rebasing 3:d6003a550c2c "C" (C)
  rebasing 5:4526cf523425 "D" (D)
  rebasing 6:b296604d9846 "E" (E tip)
  o  6: 4870f5e7df37 E
  |
  | o  5: dc999528138a D
  |/
  o  4: 6b3e11729672 C
  |
  o  3: 57e70bad1ea3 Z
  |
  | o  2: c1e6b162678d B
  |/
  o  1: 21a6c4502885 A
  |
  o  0: b41ce7760717 R
  
Multiple branching points caused by selecting a single merge changeset:

  $ rebasewithdag -b E -d Z <<'EOS'
  >     E
  >    /|
  >   B C D  # B, C: multiple branching points
  >   | |/   # D should not be picked
  > Z | /
  >  \|/
  >   A
  >   |
  >   R
  > EOS
  rebasing 2:c1e6b162678d "B" (B)
  rebasing 3:d6003a550c2c "C" (C)
  rebasing 6:54c8f00cb91c "E" (E tip)
  o    6: 00598421b616 E
  |\
  | o  5: 6b3e11729672 C
  | |
  o |  4: 85260910e847 B
  |/
  o  3: 57e70bad1ea3 Z
  |
  | o  2: 8924700906fe D
  |/
  o  1: 21a6c4502885 A
  |
  o  0: b41ce7760717 R
  
Rebase should not extend the "--base" revset using "descendants":

  $ rebasewithdag -b B -d Z <<'EOS'
  >     E
  >    /|
  > Z B C  # descendants(B) = B+E. With E, C will be included incorrectly
  >  \|/
  >   A
  >   |
  >   R
  > EOS
  rebasing 2:c1e6b162678d "B" (B)
  rebasing 5:54c8f00cb91c "E" (E tip)
  o    5: e583bf3ff54c E
  |\
  | o  4: 85260910e847 B
  | |
  | o  3: 57e70bad1ea3 Z
  | |
  o |  2: d6003a550c2c C
  |/
  o  1: 21a6c4502885 A
  |
  o  0: b41ce7760717 R
  
Rebase should not simplify the "--base" revset using "roots":

  $ rebasewithdag -b B+E -d Z <<'EOS'
  >     E
  >    /|
  > Z B C  # roots(B+E) = B. Without E, C will be missed incorrectly
  >  \|/
  >   A
  >   |
  >   R
  > EOS
  rebasing 2:c1e6b162678d "B" (B)
  rebasing 3:d6003a550c2c "C" (C)
  rebasing 5:54c8f00cb91c "E" (E tip)
  o    5: 00598421b616 E
  |\
  | o  4: 6b3e11729672 C
  | |
  o |  3: 85260910e847 B
  |/
  o  2: 57e70bad1ea3 Z
  |
  o  1: 21a6c4502885 A
  |
  o  0: b41ce7760717 R
  
The destination is one of the two branching points of a merge:

  $ rebasewithdag -b F -d Z <<'EOS'
  >     F
  >    / \
  >   E   D
  >  /   /
  > Z   C
  >  \ /
  >   B
  >   |
  >   A
  > EOS
  nothing to rebase
  [1]

Multiple branching points caused by multiple bases (issue5420):

  $ rebasewithdag -b E1+E2+C2+B1 -d Z <<'EOS'
  >   Z    E2
  >   |   /
  >   F E1 C2
  >   |/  /
  >   E C1 B2
  >   |/  /
  >   C B1
  >   |/
  >   B
  >   |
  >   A
  >   |
  >   R
  > EOS
  rebasing 3:a113dbaa660a "B1" (B1)
  rebasing 5:06ce7b1cc8c2 "B2" (B2)
  rebasing 6:0ac98cce32d3 "C1" (C1)
  rebasing 8:781512f5e33d "C2" (C2)
  rebasing 9:428d8c18f641 "E1" (E1)
  rebasing 11:e1bf82f6b6df "E2" (E2)
  o  12: e4a37b6fdbd2 E2
  |
  o  11: 9675bea983df E1
  |
  | o  10: 4faf5d4c80dc C2
  | |
  | o  9: d4799b1ad57d C1
  |/
  | o  8: 772732dc64d6 B2
  | |
  | o  7: ad3ac528a49f B1
  |/
  o  6: 2cbdfca6b9d5 Z
  |
  o  5: fcdb3293ec13 F
  |
  o  4: a4652bb8ac54 E
  |
  o  3: bd5548558fcf C
  |
  o  2: c1e6b162678d B
  |
  o  1: 21a6c4502885 A
  |
  o  0: b41ce7760717 R
  
Multiple branching points with multiple merges:

  $ rebasewithdag -b G+P -d Z <<'EOS'
  > G   H   P
  > |\ /|   |\
  > F E D   M N
  >  \|/|  /| |\
  > Z C B I J K L
  >  \|/  |/  |/
  >   A   A   A
  > EOS
  rebasing 2:dc0947a82db8 "C" (C)
  rebasing 8:4e4f9194f9f1 "D" (D)
  rebasing 9:03ca77807e91 "E" (E)
  rebasing 10:afc707c82df0 "F" (F)
  rebasing 13:690dfff91e9e "G" (G)
  rebasing 14:2893b886bb10 "H" (H)
  rebasing 3:08ebfeb61bac "I" (I)
  rebasing 4:a0a5005cec67 "J" (J)
  rebasing 5:83780307a7e8 "K" (K)
  rebasing 6:e131637a1cb6 "L" (L)
  rebasing 11:d1f6d0c3c7e4 "M" (M)
  rebasing 12:7aaec6f81888 "N" (N)
  rebasing 15:325bc8f1760d "P" (P tip)
  o    15: 6ef6a0ea3b18 P
  |\
  | o    14: 20ba3610a7e5 N
  | |\
  o \ \    13: cd4f6c06d2ab M
  |\ \ \
  | | | o  12: bca872041455 L
  | | | |
  | | o |  11: 7bbb6c8a6ad7 K
  | | |/
  | o /  10: de0cbffe893e J
  | |/
  o /  9: 0e710f176a88 I
  |/
  | o    8: 52507bab39ca H
  | |\
  | | | o  7: bb5fe4652f0d G
  | | |/|
  | | | o  6: f4ad4b31daf4 F
  | | | |
  | | o |  5: b168f85f2e78 E
  | | |/
  | o |  4: 8d09fcdb5594 D
  | |\|
  +---o  3: ab70b4c5a9c9 C
  | |
  o |  2: 262e37e34f63 Z
  | |
  | o  1: 112478962961 B
  |/
  o  0: 426bada5c675 A
  
Slightly more complex merge case (mentioned in https://www.mercurial-scm.org/pipermail/mercurial-devel/2016-November/091074.html):

  $ rebasewithdag -b A3+B3 -d Z <<'EOF'
  > Z     C1    A3     B3
  > |    /     / \    / \
  > M3 C0     A1  A2 B1  B2
  > | /       |   |  |   |
  > M2        M1  C1 C1  M3
  > |
  > M1
  > |
  > M0
  > EOF
  rebasing 4:8817fae53c94 "C0" (C0)
  rebasing 6:06ca5dfe3b5b "B2" (B2)
  rebasing 7:73508237b032 "C1" (C1)
  rebasing 9:fdb955e2faed "A2" (A2)
  rebasing 11:4e449bd1a643 "A3" (A3)
  rebasing 10:0a33b0519128 "B1" (B1)
  rebasing 12:209327807c3a "B3" (B3 tip)
  o    12: ceb984566332 B3
  |\
  | o  11: 19d93caac497 B1
  | |
  | | o    10: 058e73d3916b A3
  | | |\
  | +---o  9: 0ba13ad72234 A2
  | | |
  | o |  8: c122c2af10c6 C1
  | | |
  o | |  7: 74275896650e B2
  | | |
  | o |  6: 455ba9bd3ea2 C0
  |/ /
  o |  5: b3d7d2fda53b Z
  | |
  o |  4: 182ab6383dd7 M3
  | |
  o |  3: 6c3f73563d5f M2
  | |
  | o  2: 88c860fffcc2 A1
  |/
  o  1: bc852baa85dd M1
  |
  o  0: dbdfc5c9bcd5 M0
  
Disconnected graph:

  $ rebasewithdag -b B -d Z <<'EOS'
  >   B
  >   |
  > Z A
  > EOS
  nothing to rebase from 112478962961 to 48b9aae0607f
  [1]

Multiple roots. Roots are ancestors of dest:

  $ rebasewithdag -b B+D -d Z <<'EOF'
  > D Z B
  >  \|\|
  >   C A
  > EOF
  rebasing 2:112478962961 "B" (B)
  rebasing 3:b70f76719894 "D" (D)
  o  4: 511efad7bf13 D
  |
  | o  3: 25c4e279af62 B
  |/
  o    2: 3a49f54d7bb1 Z
  |\
  | o  1: 96cc3511f894 C
  |
  o  0: 426bada5c675 A
  
Multiple roots. One root is not an ancestor of dest:

  $ rebasewithdag -b B+D -d Z <<'EOF'
  > Z B D
  >  \|\|
  >   A C
  > EOF
  nothing to rebase from f675d5a1c6a4+b70f76719894 to 262e37e34f63
  [1]

Multiple roots. One root is not an ancestor of dest. Select using a merge:

  $ rebasewithdag -b E -d Z <<'EOF'
  >   E
  >   |\
  > Z B D
  >  \|\|
  >   A C
  > EOF
  rebasing 2:f675d5a1c6a4 "B" (B)
  rebasing 5:f68696fe6af8 "E" (E tip)
  o    5: f6e6f5081554 E
  |\
  | o    4: 30cabcba27be B
  | |\
  | | o  3: 262e37e34f63 Z
  | | |
  o | |  2: b70f76719894 D
  |/ /
  o /  1: 96cc3511f894 C
   /
  o  0: 426bada5c675 A
  
Multiple roots. Two children share two parents while dest has only one parent:

  $ rebasewithdag -b B+D -d Z <<'EOF'
  > Z B D
  >  \|\|\
  >   A C A
  > EOF
  rebasing 2:f675d5a1c6a4 "B" (B)
  rebasing 3:c2a779e13b56 "D" (D)
  o    4: 5eecd056b5f8 D
  |\
  +---o  3: 30cabcba27be B
  | |/
  | o  2: 262e37e34f63 Z
  | |
  o |  1: 96cc3511f894 C
   /
  o  0: 426bada5c675 A