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-#!/bin/sh
-
-test_description='test handling of inter-pack delta cycles during repack
-
-The goal here is to create a situation where we have two blobs, A and B, with A
-as a delta against B in one pack, and vice versa in the other. Then if we can
-persuade a full repack to find A from one pack and B from the other, that will
-give us a cycle when we attempt to reuse those deltas.
-
-The trick is in the "persuade" step, as it depends on the internals of how
-pack-objects picks which pack to reuse the deltas from. But we can assume
-that it does so in one of two general strategies:
-
- 1. Using a static ordering of packs. In this case, no inter-pack cycles can
-    happen. Any objects with a delta relationship must be present in the same
-    pack (i.e., no "--thin" packs on disk), so we will find all related objects
-    from that pack. So assuming there are no cycles within a single pack (and
-    we avoid generating them via pack-objects or importing them via
-    index-pack), then our result will have no cycles.
-
-    So this case should pass the tests no matter how we arrange things.
-
- 2. Picking the next pack to examine based on locality (i.e., where we found
-    something else recently).
-
-    In this case, we want to make sure that we find the delta versions of A and
-    B and not their base versions. We can do this by putting two blobs in each
-    pack. The first is a "dummy" blob that can only be found in the pack in
-    question.  And then the second is the actual delta we want to find.
-
-    The two blobs must be present in the same tree, not present in other trees,
-    and the dummy pathname must sort before the delta path.
-
-The setup below focuses on case 2. We have two commits HEAD and HEAD^, each
-which has two files: "dummy" and "file". Then we can make two packs which
-contain:
-
-  [pack one]
-  HEAD:dummy
-  HEAD:file  (as delta against HEAD^:file)
-  HEAD^:file (as base)
-
-  [pack two]
-  HEAD^:dummy
-  HEAD^:file (as delta against HEAD:file)
-  HEAD:file  (as base)
-
-Then no matter which order we start looking at the packs in, we know that we
-will always find a delta for "file", because its lookup will always come
-immediately after the lookup for "dummy".
-'
-. ./test-lib.sh
-
-
-
-# Create a pack containing the tree $1 and blob $1:file, with
-# the latter stored as a delta against $2:file.
-#
-# We convince pack-objects to make the delta in the direction of our choosing
-# by marking $2 as a preferred-base edge. That results in $1:file as a thin
-# delta, and index-pack completes it by adding $2:file as a base.
-#
-# Note that the two variants of "file" must be similar enough to convince git
-# to create the delta.
-make_pack () {
-	{
-		printf '%s\n' "-$(git rev-parse $2)"
-		printf '%s dummy\n' "$(git rev-parse $1:dummy)"
-		printf '%s file\n' "$(git rev-parse $1:file)"
-	} |
-	git pack-objects --stdout |
-	git index-pack --stdin --fix-thin
-}
-
-test_expect_success 'setup' '
-	test-tool genrandom base 4096 >base &&
-	for i in one two
-	do
-		# we want shared content here to encourage deltas...
-		cp base file &&
-		echo $i >>file &&
-
-		# ...whereas dummy should be short, because we do not want
-		# deltas that would create duplicates when we --fix-thin
-		echo $i >dummy &&
-
-		git add file dummy &&
-		test_tick &&
-		git commit -m $i ||
-		return 1
-	done &&
-
-	make_pack HEAD^ HEAD &&
-	make_pack HEAD HEAD^
-'
-
-test_expect_success 'repack' '
-	# We first want to check that we do not have any internal errors,
-	# and also that we do not hit the last-ditch cycle-breaking code
-	# in write_object(), which will issue a warning to stderr.
-	git repack -ad 2>stderr &&
-	test_must_be_empty stderr &&
-
-	# And then double-check that the resulting pack is usable (i.e.,
-	# we did not fail to notice any cycles). We know we are accessing
-	# the objects via the new pack here, because "repack -d" will have
-	# removed the others.
-	git cat-file blob HEAD:file >/dev/null &&
-	git cat-file blob HEAD^:file >/dev/null
-'
-
-test_done