Merge branch 'jt/avoid-prefetch-when-able-in-diff'

Test-coverage enhancement.

* jt/avoid-prefetch-when-able-in-diff:
  t4067: make rename detection test output raw diff

Author: gitster

t/t4067-diff-partial-clone.sh

@@ -125,8 +125,8 @@ test_expect_success 'diff with rename detection batches blobs' '
 
 	# Ensure that there is exactly 1 negotiation by checking that there is
 	# only 1 "done" line sent. ("done" marks the end of negotiation.)
-	GIT_TRACE_PACKET="$(pwd)/trace" git -C client diff -M HEAD^ HEAD >out &&
-	grep "similarity index" out &&
+	GIT_TRACE_PACKET="$(pwd)/trace" git -C client diff --raw -M HEAD^ HEAD >out &&
+	grep ":100644 100644.*R[0-9][0-9][0-9].*b.*c" out &&
 	grep "git> done" trace >done_lines &&
 	test_line_count = 1 done_lines
 '