ref-filter: add --no-contains option to tag/branch/for-each-ref

Change the tag, branch & for-each-ref commands to have a --no-contains
option in addition to their longstanding --contains options.

This allows for finding the last-good rollout tag given a known-bad
<commit>. Given a hypothetically bad commit cf5c7253e0, the git
version to revert to can be found with this hacky two-liner:

    (git tag -l 'v[0-9]*'; git tag -l --contains cf5c7253e0 'v[0-9]*') |
        sort | uniq -c | grep -E '^ *1 ' | awk '{print $2}' | tail -n 10

With this new --no-contains option the same can be achieved with:

    git tag -l --no-contains cf5c7253e0 'v[0-9]*' | sort | tail -n 10

As the filtering machinery is shared between the tag, branch &
for-each-ref commands, implement this for those commands too. A
practical use for this with "branch" is e.g. finding branches which
were branched off between v2.8.0 and v2.10.0:

    git branch --contains v2.8.0 --no-contains v2.10.0

The "describe" command also has a --contains option, but its semantics
are unrelated to what tag/branch/for-each-ref use --contains for. A
--no-contains option for "describe" wouldn't make any sense, other
than being exactly equivalent to not supplying --contains at all,
which would be confusing at best.

Add a --without option to "tag" as an alias for --no-contains, for
consistency with --with and --contains.  The --with option is
undocumented, and possibly the only user of it is
Junio (<xmqqefy71iej.fsf@gitster.mtv.corp.google.com>). But it's
trivial to support, so let's do that.

The additions to the the test suite are inverse copies of the
corresponding --contains tests. With this change --no-contains for
tag, branch & for-each-ref is just as well tested as the existing
--contains option.

In addition to those tests, add a test for "tag" which asserts that
--no-contains won't find tree/blob tags, which is slightly
unintuitive, but consistent with how --contains works & is documented.

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

1 files changed, 126 insertions, 4 deletions

diff --git a/t/t7004-tag.sh b/t/t7004-tag.sh
index 3529c3009c..8a6e8032da 100755
--- a/t/t7004-tag.sh
+++ b/t/t7004-tag.sh
@@ -1424,6 +1424,23 @@ test_expect_success 'checking that first commit is in all tags (relative)' "
 	test_cmp expected actual
 "
 
+# All the --contains tests above, but with --no-contains
+test_expect_success 'checking that first commit is not listed in any tag with --no-contains  (hash)' "
+	>expected &&
+	git tag -l --no-contains $hash1 v* >actual &&
+	test_cmp expected actual
+"
+
+test_expect_success 'checking that first commit is in all tags (tag)' "
+	git tag -l --no-contains v1.0 v* >actual &&
+	test_cmp expected actual
+"
+
+test_expect_success 'checking that first commit is in all tags (relative)' "
+	git tag -l --no-contains HEAD~2 v* >actual &&
+	test_cmp expected actual
+"
+
 cat > expected <<EOF
 v2.0
 EOF
@@ -1433,6 +1450,17 @@ test_expect_success 'checking that second commit only has one tag' "
 	test_cmp expected actual
 "
 
+cat > expected <<EOF
+v0.2.1
+v1.0
+v1.0.1
+v1.1.3
+EOF
+
+test_expect_success 'inverse of the last test, with --no-contains' "
+	git tag -l --no-contains $hash2 v* >actual &&
+	test_cmp expected actual
+"
 
 cat > expected <<EOF
 EOF
@@ -1442,6 +1470,19 @@ test_expect_success 'checking that third commit has no tags' "
 	test_cmp expected actual
 "
 
+cat > expected <<EOF
+v0.2.1
+v1.0
+v1.0.1
+v1.1.3
+v2.0
+EOF
+
+test_expect_success 'conversely --no-contains on the third commit lists all tags' "
+	git tag -l --no-contains $hash3 v* >actual &&
+	test_cmp expected actual
+"
+
 # how about a simple merge?
 
 test_expect_success 'creating simple branch' '
@@ -1463,6 +1504,19 @@ test_expect_success 'checking that branch head only has one tag' "
 	test_cmp expected actual
 "
 
+cat > expected <<EOF
+v0.2.1
+v1.0
+v1.0.1
+v1.1.3
+v2.0
+EOF
+
+test_expect_success 'checking that branch head with --no-contains lists all but one tag' "
+	git tag -l --no-contains $hash4 v* >actual &&
+	test_cmp expected actual
+"
+
 test_expect_success 'merging original branch into this branch' '
 	git merge --strategy=ours master &&
         git tag v4.0
@@ -1484,6 +1538,20 @@ v1.0.1
 v1.1.3
 v2.0
 v3.0
+EOF
+
+test_expect_success 'checking that original branch head with --no-contains lists all but one tag now' "
+	git tag -l --no-contains $hash3 v* >actual &&
+	test_cmp expected actual
+"
+
+cat > expected <<EOF
+v0.2.1
+v1.0
+v1.0.1
+v1.1.3
+v2.0
+v3.0
 v4.0
 EOF
 
@@ -1497,6 +1565,12 @@ test_expect_success 'checking that --contains can be used in non-list mode' '
 	test_cmp expected actual
 '
 
+test_expect_success 'checking that initial commit is in all tags with --no-contains' "
+	>expected &&
+	git tag -l --no-contains $hash1 v* >actual &&
+	test_cmp expected actual
+"
+
 # mixing modes and options:
 
 test_expect_success 'mixing incompatibles modes and options is forbidden' '
@@ -1522,10 +1596,13 @@ test_expect_success 'mixing incompatibles modes and options is forbidden' '
 	test_must_fail git tag -l -F some file &&
 	test_must_fail git tag -v -s &&
 	test_must_fail git tag --contains tag-tree &&
-	test_must_fail git tag --contains tag-blob
+	test_must_fail git tag --contains tag-blob &&
+	test_must_fail git tag --no-contains tag-tree &&
+	test_must_fail git tag --no-contains tag-blob &&
+	test_must_fail git tag --contains --no-contains
 '
 
-for option in --contains --merged --no-merged --points-at
+for option in --contains --no-contains --merged --no-merged --points-at
 do
 	test_expect_success "mixing incompatible modes with $option is forbidden" "
 		test_must_fail git tag -d $option HEAD &&
@@ -1792,7 +1869,7 @@ run_with_limited_stack () {
 test_lazy_prereq ULIMIT_STACK_SIZE 'run_with_limited_stack true'
 
 # we require ulimit, this excludes Windows
-test_expect_success ULIMIT_STACK_SIZE '--contains works in a deep repo' '
+test_expect_success ULIMIT_STACK_SIZE '--contains and --no-contains work in a deep repo' '
 	>expect &&
 	i=1 &&
 	while test $i -lt 8000
@@ -1808,7 +1885,9 @@ EOF"
 	git checkout master &&
 	git tag far-far-away HEAD^ &&
 	run_with_limited_stack git tag --contains HEAD >actual &&
-	test_cmp expect actual
+	test_cmp expect actual &&
+	run_with_limited_stack git tag --no-contains HEAD >actual &&
+	test_line_count ">" 10 actual
 '
 
 test_expect_success '--format should list tags as per format given' '
@@ -1870,4 +1949,47 @@ test_expect_success 'ambiguous branch/tags not marked' '
 	test_cmp expect actual
 '
 
+test_expect_success '--contains combined with --no-contains' '
+	(
+		git init no-contains &&
+		cd no-contains &&
+		test_commit v0.1 &&
+		test_commit v0.2 &&
+		test_commit v0.3 &&
+		test_commit v0.4 &&
+		test_commit v0.5 &&
+		cat >expected <<-\EOF &&
+		v0.2
+		v0.3
+		v0.4
+		EOF
+		git tag --contains v0.2 --no-contains v0.5 >actual &&
+		test_cmp expected actual
+	)
+'
+
+# As the docs say, list tags which contain a specified *commit*. We
+# don't recurse down to tags for trees or blobs pointed to by *those*
+# commits.
+test_expect_success 'Does --[no-]contains stop at commits? Yes!' '
+	cd no-contains &&
+	blob=$(git rev-parse v0.3:v0.3.t) &&
+	tree=$(git rev-parse v0.3^{tree}) &&
+	git tag tag-blob $blob &&
+	git tag tag-tree $tree &&
+	git tag --contains v0.3 >actual &&
+	cat >expected <<-\EOF &&
+	v0.3
+	v0.4
+	v0.5
+	EOF
+	test_cmp expected actual &&
+	git tag --no-contains v0.3 >actual &&
+	cat >expected <<-\EOF &&
+	v0.1
+	v0.2
+	EOF
+	test_cmp expected actual
+'
+
 test_done