Merge branch 'jc/maint-checkout-fix'

* jc/maint-checkout-fix:
  checkout: do not check out unmerged higher stages randomly

Conflicts:
	t/t7201-co.sh

diff --cc builtin-checkout.c
Simple merge

diff --cc t/t7201-co.sh
index 543b1c289866d01f8aa3f931f3579565a963de9d,83a366f1e7dcbe1d1678cadd87b9862713e82b97..25181388f8a8f1730d05fce128e0e1fc66eb3c0e
--- 1/t/t7201-co.sh
--- 2/t/t7201-co.sh
+++ b/t/t7201-co.sh
@@@ -337,36 -337,26 +337,58 @@@ test_expect_success 
      test refs/heads/delete-me = "$(git symbolic-ref HEAD)" &&
      test_must_fail git checkout --track -b track'
  
 +test_expect_success \
 +    'checkout with --track fakes a sensible -b <name>' '
 +    git update-ref refs/remotes/origin/koala/bear renamer &&
 +    git update-ref refs/new/koala/bear renamer &&
 +
 +    git checkout --track origin/koala/bear &&
 +    test "refs/heads/koala/bear" = "$(git symbolic-ref HEAD)" &&
 +    test "$(git rev-parse HEAD)" = "$(git rev-parse renamer)" &&
 +
 +    git checkout master && git branch -D koala/bear &&
 +
 +    git checkout --track refs/remotes/origin/koala/bear &&
 +    test "refs/heads/koala/bear" = "$(git symbolic-ref HEAD)" &&
 +    test "$(git rev-parse HEAD)" = "$(git rev-parse renamer)" &&
 +
 +    git checkout master && git branch -D koala/bear &&
 +
 +    git checkout --track remotes/origin/koala/bear &&
 +    test "refs/heads/koala/bear" = "$(git symbolic-ref HEAD)" &&
 +    test "$(git rev-parse HEAD)" = "$(git rev-parse renamer)" &&
 +
 +    git checkout master && git branch -D koala/bear &&
 +
 +    git checkout --track refs/new/koala/bear &&
 +    test "refs/heads/koala/bear" = "$(git symbolic-ref HEAD)" &&
 +    test "$(git rev-parse HEAD)" = "$(git rev-parse renamer)"
 +'
 +
 +test_expect_success \
 +    'checkout with --track, but without -b, fails with too short tracked name' '
 +    test_must_fail git checkout --track renamer'
 +
+ test_expect_success 'checkout an unmerged path should fail' '
+       rm -f .git/index &&
+       O=$(echo original | git hash-object -w --stdin) &&
+       A=$(echo ourside | git hash-object -w --stdin) &&
+       B=$(echo theirside | git hash-object -w --stdin) &&
+       (
+               echo "100644 $A 0       fild" &&
+               echo "100644 $O 1       file" &&
+               echo "100644 $A 2       file" &&
+               echo "100644 $B 3       file" &&
+               echo "100644 $A 0       filf"
+       ) | git update-index --index-info &&
+       echo "none of the above" >sample &&
+       cat sample >fild &&
+       cat sample >file &&
+       cat sample >filf &&
+       test_must_fail git checkout fild file filf &&
+       test_cmp sample fild &&
+       test_cmp sample filf &&
+       test_cmp sample file
+ '
+ 
  test_done