revisions API: call diff_free(&revs->pruning) in revisions_release()

Call diff_free() on the "pruning" member of "struct rev_info".  Doing
so makes several tests pass under SANITIZE=leak.

This was also the last missing piece that allows us to remove the
UNLEAK() in "cmd_diff" and "cmd_diff_index", which allows us to use
those commands as a canary for general leaks in the revisions API. See
[1] for further rationale, and 886e1084d7 (builtin/: add UNLEAKs,
2017-10-01) for the commit that added the UNLEAK() there.

1. https://lore.kernel.org/git/220218.861r00ib86.gmgdl@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/diff-index.c

@@ -70,7 +70,6 @@ int cmd_diff_index(int argc, const char **argv, const char *prefix)
 		return -1;
 	}
 	result = run_diff_index(&rev, option);
-	UNLEAK(rev);
 	result = diff_result_code(&rev.diffopt, result);
 	release_revisions(&rev);
 	return result;

builtin/diff.c

@@ -594,7 +594,6 @@ int cmd_diff(int argc, const char **argv, const char *prefix)
 	result = diff_result_code(&rev.diffopt, result);
 	if (1 < rev.diffopt.skip_stat_unmatch)
 		refresh_index_quietly();
-	UNLEAK(rev);
 	release_revisions(&rev);
 	UNLEAK(ent);
 	UNLEAK(blob);

revision.c

@@ -2953,6 +2953,7 @@ void release_revisions(struct rev_info *revs)
 	clear_pathspec(&revs->prune_data);
 	release_revisions_mailmap(revs->mailmap);
 	free_grep_patterns(&revs->grep_filter);
+	diff_free(&revs->pruning);
 	reflog_walk_info_release(revs->reflog_info);
 }
 

t/t1001-read-tree-m-2way.sh

@@ -21,6 +21,7 @@ In the test, these paths are used:
 	yomin   - not in H or M
 '
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-read-tree.sh
 

t/t1002-read-tree-m-u-2way.sh

@@ -9,6 +9,7 @@ This is identical to t1001, but uses -u to update the work tree as well.
 
 '
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-read-tree.sh
 

t/t2200-add-update.sh

@@ -14,6 +14,7 @@ only the updates to dir/sub.
 Also tested are "git add -u" without limiting, and "git add -u"
 without contents changes, and other conditions'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success setup '

t/t4039-diff-assume-unchanged.sh

@@ -2,6 +2,7 @@
 
 test_description='diff with assume-unchanged entries'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 # external diff has been tested in t4020-diff-external.sh

t/t4206-log-follow-harder-copies.sh

@@ -6,6 +6,8 @@
 test_description='Test --follow should always find copies hard in git log.
 
 '
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-diff.sh
 

t/t6131-pathspec-icase.sh

@@ -1,6 +1,8 @@
 #!/bin/sh
 
 test_description='test case insensitive pathspec limiting'
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 if test_have_prereq CASE_INSENSITIVE_FS