tests: demonstrate broken rebase of merge with p1's successor in dest

The fix in 8ede973597fd (rebase: handle successor targets (issue5198),
2016-04-11) only fixed the case where p2's successor was in the
destination, and only when the successor was exactly the destination
(i.e. not when the successor was an ancestor of it). This patch adds a
test case for when p1's successor is in the destination. It adds
another one for when the successor is an ancestor of the
destination. To do that simply, it also rewrites the test case using
drawdag.

Differential Revision: https://phab.mercurial-scm.org/D211

tests/test-rebase-obsolete.t

@@ -13,6 +13,7 b' Enable obsolete'
   > publish=False
   > [extensions]
   > rebase=
+  > drawdag=$TESTDIR/drawdag.py
   > EOF
 
 Setup rebase canonical repo
@@ -896,55 +897,202 b' Create the changes that we will rebase'
   rebasing 22:7bdc8a87673d "dummy change" (tip)
   $ cd ..
 
-rebase source is obsoleted (issue5198)
----------------------------------
+Rebase merge where successor of one parent is equal to destination (issue5198)
+
+  $ hg init p1-succ-is-dest
+  $ cd p1-succ-is-dest
 
-  $ hg clone base amended
-  updating to branch default
-  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
-  $ cd amended
-  $ hg up 9520eea781bc
-  1 files updated, 0 files merged, 2 files removed, 0 files unresolved
-  $ echo 1 >> E
-  $ hg commit --amend -m "E'" -d "0 0"
+  $ hg debugdrawdag <<EOF
+  >   F
+  >  /|
+  > E D B # replace: D -> B
+  >  \|/
+  >   A
+  > EOF
+
+  $ hg rebase -d B -s D
+  note: not rebasing 2:b18e25de2cf5 "D" (D), already in destination as 1:112478962961 "B"
+  rebasing 4:66f1a38021c9 "F" (F tip)
   $ hg log -G
-  @  9:69abe8906104 E'
-  |
-  | o  7:02de42196ebe H
-  | |
-  | | o  6:eea13746799a G
+  o    5:50e9d60b99c6 F
+  |\
+  | | x  4:66f1a38021c9 F
   | |/|
-  | o |  5:24b6387c8c8c F
-  |/ /
-  | x  4:9520eea781bc E
+  | o |  3:7fb047a69f22 E
+  | | |
+  | | x  2:b18e25de2cf5 D
+  | |/
+  o |  1:112478962961 B
   |/
-  | o  3:32af7686d403 D
+  o  0:426bada5c675 A
+  
+  $ cd ..
+
+Rebase merge where successor of other parent is equal to destination
+
+  $ hg init p2-succ-is-dest
+  $ cd p2-succ-is-dest
+
+  $ hg debugdrawdag <<EOF
+  >   F
+  >  /|
+  > E D B # replace: E -> B
+  >  \|/
+  >   A
+  > EOF
+
+BROKEN: Raises an exception
+  $ hg rebase -d B -s E 2>&1 | grep AssertionError:
+  AssertionError: no base found to rebase on (defineparents called wrong)
+  $ hg log -G
+  o    4:66f1a38021c9 F
+  |\
+  | x  3:7fb047a69f22 E
   | |
-  | o  2:5fddd98957c8 C
-  | |
-  | o  1:42ccdea3bb16 B
+  o |  2:b18e25de2cf5 D
   |/
-  o  0:cd010b8cd998 A
+  | o  1:112478962961 B
+  |/
+  o  0:426bada5c675 A
   
-  $ hg rebase -d . -s 9520eea781bc
-  note: not rebasing 4:9520eea781bc "E", already in destination as 9:69abe8906104 "E'"
-  rebasing 6:eea13746799a "G"
+  $ cd ..
+
+Rebase merge where successor of one parent is ancestor of destination
+
+  $ hg init p1-succ-in-dest
+  $ cd p1-succ-in-dest
+
+  $ hg debugdrawdag <<EOF
+  >   F C
+  >  /| |
+  > E D B # replace: D -> B
+  >  \|/
+  >   A
+  > EOF
+
+  $ hg rebase -d C -s D
+  note: not rebasing 2:b18e25de2cf5 "D" (D), already in destination as 1:112478962961 "B"
+  rebasing 5:66f1a38021c9 "F" (F tip)
+BROKEN: not rebased on top of requested destination (C)
   $ hg log -G
-  o    10:17be06e82e95 G
+  o    6:50e9d60b99c6 F
+  |\
+  | | x  5:66f1a38021c9 F
+  | |/|
+  +-----o  4:26805aba1e60 C
+  | | |
+  | o |  3:7fb047a69f22 E
+  | | |
+  | | x  2:b18e25de2cf5 D
+  | |/
+  o |  1:112478962961 B
+  |/
+  o  0:426bada5c675 A
+  
+  $ cd ..
+
+Rebase merge where successor of other parent is ancestor of destination
+
+  $ hg init p2-succ-in-dest
+  $ cd p2-succ-in-dest
+
+  $ hg debugdrawdag <<EOF
+  >   F C
+  >  /| |
+  > E D B # replace: E -> B
+  >  \|/
+  >   A
+  > EOF
+
+BROKEN: Raises an exception
+  $ hg rebase -d C -s E 2>&1 | grep AssertionError:
+  AssertionError: no base found to rebase on (defineparents called wrong)
+  $ hg log -G
+  o    5:66f1a38021c9 F
   |\
-  | @  9:69abe8906104 E'
-  | |
-  +---o  7:02de42196ebe H
-  | |
-  o |  5:24b6387c8c8c F
+  | | o  4:26805aba1e60 C
+  | | |
+  | x |  3:7fb047a69f22 E
+  | | |
+  o | |  2:b18e25de2cf5 D
+  |/ /
+  | o  1:112478962961 B
   |/
-  | o  3:32af7686d403 D
-  | |
-  | o  2:5fddd98957c8 C
-  | |
-  | o  1:42ccdea3bb16 B
+  o  0:426bada5c675 A
+  
+  $ cd ..
+
+Rebase merge where successor of one parent is ancestor of destination
+
+  $ hg init p1-succ-in-dest-b
+  $ cd p1-succ-in-dest-b
+
+  $ hg debugdrawdag <<EOF
+  >   F C
+  >  /| |
+  > E D B # replace: E -> B
+  >  \|/
+  >   A
+  > EOF
+
+  $ hg rebase -d C -b F
+  rebasing 2:b18e25de2cf5 "D" (D)
+  note: not rebasing 3:7fb047a69f22 "E" (E), already in destination as 1:112478962961 "B"
+  rebasing 5:66f1a38021c9 "F" (F tip)
+  $ hg log -G
+  o  7:9ed45af61fa0 F
+  |
+  o  6:8f47515dda15 D
+  |
+  | x    5:66f1a38021c9 F
+  | |\
+  o | |  4:26805aba1e60 C
+  | | |
+  | | x  3:7fb047a69f22 E
+  | | |
+  | x |  2:b18e25de2cf5 D
+  | |/
+  o /  1:112478962961 B
   |/
-  o  0:cd010b8cd998 A
+  o  0:426bada5c675 A
+  
+  $ cd ..
+
+Rebase merge where successor of other parent is ancestor of destination
+
+  $ hg init p2-succ-in-dest-b
+  $ cd p2-succ-in-dest-b
+
+  $ hg debugdrawdag <<EOF
+  >   F C
+  >  /| |
+  > E D B # replace: D -> B
+  >  \|/
+  >   A
+  > EOF
+
+  $ hg rebase -d C -b F
+  note: not rebasing 2:b18e25de2cf5 "D" (D), already in destination as 1:112478962961 "B"
+  rebasing 3:7fb047a69f22 "E" (E)
+  rebasing 5:66f1a38021c9 "F" (F tip)
+BROKEN: This should have resulted in a rebased F with one parent, just like in
+the test case above
+  $ hg log -G
+  o    7:c1e6f26e339d F
+  |\
+  | o  6:533690786a86 E
+  |/
+  | x    5:66f1a38021c9 F
+  | |\
+  o | |  4:26805aba1e60 C
+  | | |
+  | | x  3:7fb047a69f22 E
+  | | |
+  | x |  2:b18e25de2cf5 D
+  | |/
+  o /  1:112478962961 B
+  |/
+  o  0:426bada5c675 A
   
   $ cd ..