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 t4220 diff-hunks test fixtures
 ==============================

 trim-divergent-old, trim-divergent-new
 --------------------------------------

 Two revisions of a single real file, used by t4220-diff-hunks.sh to
 exercise a "trim-divergent" blob pair: one whose diff hunk counts change
 with the amount of context, so the trimmed and untrimmed results
 disagree.

 They are two versions of git's own t/t6002-rev-list-bisect.sh, taken from
 git.git history around:

   090af9957c ("t6002: fix use of `expr` with `set -e`",
   Patrick Steinhardt, 2026-04-21)

 which rewrites `$(expr ...)` arithmetic as `$((...))` and reformats a few
 test_expect_success blocks.

   trim-divergent-old = 090af9957c^:t/t6002-rev-list-bisect.sh  (blob daa009c9a1)
   trim-divergent-new = 090af9957c :t/t6002-rev-list-bisect.sh  (blob f2de40b5ed)

 To regenerate them from any git.git checkout:

   git show 090af9957c^:t/t6002-rev-list-bisect.sh >trim-divergent-old
   git show 090af9957c:t/t6002-rev-list-bisect.sh  >trim-divergent-new

 Why this pair
 -------------

 The diff-hunks store records only "trim-stable" pairs: those whose hunks
 are identical whether or not xdiff trims the common head and tail (which
 it does at zero context, in trim_common_tail).  This pair is deliberately
 NOT trim-stable:

   diff -U0 reports  9 added / 6 deleted
   diff -U3 reports 10 added / 7 deleted

 Because the counts diverge with context, the writer must refuse to record
 this pair and every command must recompute it from the blobs.  t4220 uses
 it to prove that the displayed counts stay correct at each context, and
 that a divergent pair is never served from the store.  See
 t4220-diff-hunks.sh ("a trim-divergent file is correct at each context"
 and the store-poison test).

 Why not a synthesized fixture
 -----------------------------

 The divergence needs real content that makes xdiff's common-tail trimming
 shift a hunk boundary while the added/deleted balance stays equal.  A
 minimal hand-written file that reliably triggers the -U0 vs -U3 count
 disagreement has not been found yet; until one is, this real pair is kept
 verbatim.  If you synthesize a smaller equivalent, replace these two files
 and delete this note.
	t4220 diff-hunks test fixtures
	==============================

	trim-divergent-old, trim-divergent-new
	--------------------------------------

	Two revisions of a single real file, used by t4220-diff-hunks.sh to
	exercise a "trim-divergent" blob pair: one whose diff hunk counts change
	with the amount of context, so the trimmed and untrimmed results
	disagree.

	They are two versions of git's own t/t6002-rev-list-bisect.sh, taken from
	git.git history around:

	090af9957c ("t6002: fix use of `expr` with `set -e`",
	Patrick Steinhardt, 2026-04-21)

	which rewrites `$(expr ...)` arithmetic as `$((...))` and reformats a few
	test_expect_success blocks.

	trim-divergent-old = 090af9957c^:t/t6002-rev-list-bisect.sh (blob daa009c9a1)
	trim-divergent-new = 090af9957c :t/t6002-rev-list-bisect.sh (blob f2de40b5ed)

	To regenerate them from any git.git checkout:

	git show 090af9957c^:t/t6002-rev-list-bisect.sh >trim-divergent-old
	git show 090af9957c:t/t6002-rev-list-bisect.sh >trim-divergent-new

	Why this pair
	-------------

	The diff-hunks store records only "trim-stable" pairs: those whose hunks
	are identical whether or not xdiff trims the common head and tail (which
	it does at zero context, in trim_common_tail). This pair is deliberately
	NOT trim-stable:

	diff -U0 reports 9 added / 6 deleted
	diff -U3 reports 10 added / 7 deleted

	Because the counts diverge with context, the writer must refuse to record
	this pair and every command must recompute it from the blobs. t4220 uses
	it to prove that the displayed counts stay correct at each context, and
	that a divergent pair is never served from the store. See
	t4220-diff-hunks.sh ("a trim-divergent file is correct at each context"
	and the store-poison test).

	Why not a synthesized fixture
	-----------------------------

	The divergence needs real content that makes xdiff's common-tail trimming
	shift a hunk boundary while the added/deleted balance stays equal. A
	minimal hand-written file that reliably triggers the -U0 vs -U3 count
	disagreement has not been found yet; until one is, this real pair is kept
	verbatim. If you synthesize a smaller equivalent, replace these two files
	and delete this note.