#!/bin/sh

global test_description := ''
Test pruning of repositories with minor corruptions. The goal
here is that we should always be erring on the side of safety. So
if we see, for example, a ref with a bogus name, it is OK either to
bail out or to proceed using it as a reachable tip, but it is _not_
OK to proceed as if it did not exist. Otherwise we might silently
delete objects that cannot be recovered.
''
source ./test-lib.sh

test_expect_success 'disable reflogs' '
	git config core.logallrefupdates false &&
	git reflog expire --expire=all --all
'

test_expect_success 'create history reachable only from a bogus-named ref' '
	test_tick && git commit --allow-empty -m master &&
	base=$(git rev-parse HEAD) &&
	test_tick && git commit --allow-empty -m bogus &&
	bogus=$(git rev-parse HEAD) &&
	git cat-file commit $bogus >saved &&
	echo $bogus >.git/refs/heads/bogus..name &&
	git reset --hard HEAD^
'

test_expect_success 'pruning does not drop bogus object' '
	test_when_finished "git hash-object -w -t commit saved" &&
	test_might_fail git prune --expire=now &&
	verbose git cat-file -e $bogus
'

test_expect_success 'put bogus object into pack' '
	git tag reachable $bogus &&
	git repack -ad &&
	git tag -d reachable &&
	verbose git cat-file -e $bogus
'

test_expect_success 'destructive repack keeps packed object' '
	test_might_fail git repack -Ad --unpack-unreachable=now &&
	verbose git cat-file -e $bogus &&
	test_might_fail git repack -ad &&
	verbose git cat-file -e $bogus
'

# subsequent tests will have different corruptions
test_expect_success 'clean up bogus ref' '
	rm .git/refs/heads/bogus..name
'

# We create two new objects here, "one" and "two". Our
# master branch points to "two", which is deleted,
# corrupting the repository. But we'd like to make sure
# that the otherwise unreachable "one" is not pruned
# (since it is the user's best bet for recovering
# from the corruption).
#
# Note that we also point HEAD somewhere besides "two",
# as we want to make sure we test the case where we
# pick up the reference to "two" by iterating the refs,
# not by resolving HEAD.
test_expect_success 'create history with missing tip commit' '
	test_tick && git commit --allow-empty -m one &&
	recoverable=$(git rev-parse HEAD) &&
	git cat-file commit $recoverable >saved &&
	test_tick && git commit --allow-empty -m two &&
	missing=$(git rev-parse HEAD) &&
	git checkout --detach $base &&
	rm .git/objects/$(echo $missing | sed "s,..,&/,") &&
	test_must_fail git cat-file -e $missing
'

test_expect_success 'pruning with a corrupted tip does not drop history' '
	test_when_finished "git hash-object -w -t commit saved" &&
	test_might_fail git prune --expire=now &&
	verbose git cat-file -e $recoverable
'

test_expect_success 'pack-refs does not silently delete broken loose ref' '
	git pack-refs --all --prune &&
	echo $missing >expect &&
	git rev-parse refs/heads/master >actual &&
	test_cmp expect actual
'

# we do not want to count on running pack-refs to
# actually pack it, as it is perfectly reasonable to
# skip processing a broken ref
test_expect_success 'create packed-refs file with broken ref' '
	rm -f .git/refs/heads/master &&
	cat >.git/packed-refs <<-EOF &&
	$missing refs/heads/master
	$recoverable refs/heads/other
	EOF
	echo $missing >expect &&
	git rev-parse refs/heads/master >actual &&
	test_cmp expect actual
'

test_expect_success 'pack-refs does not silently delete broken packed ref' '
	git pack-refs --all --prune &&
	git rev-parse refs/heads/master >actual &&
	test_cmp expect actual
'

test_expect_success 'pack-refs does not drop broken refs during deletion' '
	git update-ref -d refs/heads/other &&
	git rev-parse refs/heads/master >actual &&
	test_cmp expect actual
'

test_done
(CommandList
  children: [
    (Assignment
      keyword: Assign_None
      pairs: [
        (assign_pair
          lhs: (LhsName name:test_description)
          op: Equal
          rhs: 
            {
              (SQ <"\n"> <"Test pruning of repositories with minor corruptions. The goal\n"> 
                <"here is that we should always be erring on the side of safety. So\n"> <"if we see, for example, a ref with a bogus name, it is OK either to\n"> 
                <"bail out or to proceed using it as a reachable tip, but it is _not_\n"> <"OK to proceed as if it did not exist. Otherwise we might silently\n"> 
                <"delete objects that cannot be recovered.\n">
              )
            }
          spids: [4]
        )
      ]
      spids: [4]
    )
    (C {(.)} {(./test-lib.sh)})
    (C {(test_expect_success)} {(SQ <"disable reflogs">)} 
      {
        (SQ <"\n"> <"\tgit config core.logallrefupdates false &&\n"> 
          <"\tgit reflog expire --expire=all --all\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"create history reachable only from a bogus-named ref">)} 
      {
        (SQ <"\n"> <"\ttest_tick && git commit --allow-empty -m master &&\n"> 
          <"\tbase=$(git rev-parse HEAD) &&\n"> <"\ttest_tick && git commit --allow-empty -m bogus &&\n"> <"\tbogus=$(git rev-parse HEAD) &&\n"> 
          <"\tgit cat-file commit $bogus >saved &&\n"> <"\techo $bogus >.git/refs/heads/bogus..name &&\n"> <"\tgit reset --hard HEAD^\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"pruning does not drop bogus object">)} 
      {
        (SQ <"\n"> <"\ttest_when_finished \"git hash-object -w -t commit saved\" &&\n"> 
          <"\ttest_might_fail git prune --expire=now &&\n"> <"\tverbose git cat-file -e $bogus\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"put bogus object into pack">)} 
      {
        (SQ <"\n"> <"\tgit tag reachable $bogus &&\n"> <"\tgit repack -ad &&\n"> 
          <"\tgit tag -d reachable &&\n"> <"\tverbose git cat-file -e $bogus\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"destructive repack keeps packed object">)} 
      {
        (SQ <"\n"> <"\ttest_might_fail git repack -Ad --unpack-unreachable=now &&\n"> 
          <"\tverbose git cat-file -e $bogus &&\n"> <"\ttest_might_fail git repack -ad &&\n"> <"\tverbose git cat-file -e $bogus\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"clean up bogus ref">)} 
      {(SQ <"\n"> <"\trm .git/refs/heads/bogus..name\n">)}
    )
    (C {(test_expect_success)} {(SQ <"create history with missing tip commit">)} 
      {
        (SQ <"\n"> <"\ttest_tick && git commit --allow-empty -m one &&\n"> 
          <"\trecoverable=$(git rev-parse HEAD) &&\n"> <"\tgit cat-file commit $recoverable >saved &&\n"> 
          <"\ttest_tick && git commit --allow-empty -m two &&\n"> <"\tmissing=$(git rev-parse HEAD) &&\n"> <"\tgit checkout --detach $base &&\n"> 
          <"\trm .git/objects/$(echo $missing | sed \"s,..,&/,\") &&\n"> <"\ttest_must_fail git cat-file -e $missing\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"pruning with a corrupted tip does not drop history">)} 
      {
        (SQ <"\n"> <"\ttest_when_finished \"git hash-object -w -t commit saved\" &&\n"> 
          <"\ttest_might_fail git prune --expire=now &&\n"> <"\tverbose git cat-file -e $recoverable\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"pack-refs does not silently delete broken loose ref">)} 
      {
        (SQ <"\n"> <"\tgit pack-refs --all --prune &&\n"> <"\techo $missing >expect &&\n"> 
          <"\tgit rev-parse refs/heads/master >actual &&\n"> <"\ttest_cmp expect actual\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"create packed-refs file with broken ref">)} 
      {
        (SQ <"\n"> <"\trm -f .git/refs/heads/master &&\n"> <"\tcat >.git/packed-refs <<-EOF &&\n"> 
          <"\t$missing refs/heads/master\n"> <"\t$recoverable refs/heads/other\n"> <"\tEOF\n"> <"\techo $missing >expect &&\n"> 
          <"\tgit rev-parse refs/heads/master >actual &&\n"> <"\ttest_cmp expect actual\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"pack-refs does not silently delete broken packed ref">)} 
      {
        (SQ <"\n"> <"\tgit pack-refs --all --prune &&\n"> 
          <"\tgit rev-parse refs/heads/master >actual &&\n"> <"\ttest_cmp expect actual\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"pack-refs does not drop broken refs during deletion">)} 
      {
        (SQ <"\n"> <"\tgit update-ref -d refs/heads/other &&\n"> 
          <"\tgit rev-parse refs/heads/master >actual &&\n"> <"\ttest_cmp expect actual\n">
        )
      }
    )
    (C {(test_done)})
  ]
)