Merge branch 'kd/rev-list-bisect-first-parent'

"git rev-list --bisect --first-parent" does not work (yet) and can
even cause SEGV; forbid it.  "git log --bisect --first-parent"
would not be useful until "git bisect --first-parent" materializes,
so it is also forbidden for now.

* kd/rev-list-bisect-first-parent:
rev-list: refuse --first-parent combined with --bisect

diff --cc Documentation/rev-list-options.txt
Simple merge

diff --cc revision.c
Simple merge

diff --cc t/t6000-rev-list-misc.sh
index 2602086303edeae192606d82d7fd1e71ac76534f,97a13a574e09edb7b70782e357d5b1231747e053..1f58b46e1f1300b7e893f16b92c40f4c2a09b014
--- 1/t/t6000-rev-list-misc.sh
--- 2/t/t6000-rev-list-misc.sh
+++ b/t/t6000-rev-list-misc.sh
@@@ -73,27 -73,8 +73,31 @@@ test_expect_success 'symleft flag bit i
        test_cmp expect actual
  '
  
 +test_expect_success 'rev-list can show index objects' '
 +      # Of the blobs and trees in the index, note:
 +      #
 +      #   - we do not show two/three, because it is the
 +      #     same blob as "one", and we show objects only once
 +      #
 +      #   - we do show the tree "two", because it has a valid cache tree
 +      #     from the last commit
 +      #
 +      #   - we do not show the root tree; since we updated the index, it
 +      #     does not have a valid cache tree
 +      #
 +      cat >expect <<-\EOF
 +      8e4020bb5a8d8c873b25de15933e75cc0fc275df one
 +      d9d3a7417b9605cfd88ee6306b28dadc29e6ab08 only-in-index
 +      9200b628cf9dc883a85a7abc8d6e6730baee589c two
 +      EOF
 +      echo only-in-index >only-in-index &&
 +      git add only-in-index &&
 +      git rev-list --objects --indexed-objects >actual &&
 +      test_cmp expect actual
 +'
 +
+ test_expect_success '--bisect and --first-parent can not be combined' '
+       test_must_fail git rev-list --bisect --first-parent HEAD
+ '
+ 
  test_done