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 cf5c725, the git
version to revert to can be found with this hacky two-liner:

    (git tag -l 'v[0-9]*'; git tag -l --contains cf5c725 '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 cf5c725 '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>

Author: avar

Documentation/git-branch.txt

@@ -11,7 +11,8 @@ SYNOPSIS
 'git branch' [--color[=<when>] | --no-color] [-r | -a]
 	[--list] [-v [--abbrev=<length> | --no-abbrev]]
 	[--column[=<options>] | --no-column]
-	[(--merged | --no-merged | --contains) [<commit>]] [--sort=<key>]
+	[(--merged | --no-merged) [<commit>]]
+	[--contains [<commit]] [--no-contains [<commit>]] [--sort=<key>]
 	[--points-at <object>] [--format=<format>] [<pattern>...]
 'git branch' [--set-upstream | --track | --no-track] [-l] [-f] <branchname> [<start-point>]
 'git branch' (--set-upstream-to=<upstream> | -u <upstream>) [<branchname>]
@@ -35,7 +36,7 @@ as branch creation.
 
 With `--contains`, shows only the branches that contain the named commit
 (in other words, the branches whose tip commits are descendants of the
-named commit).  With `--merged`, only branches merged into the named
+named commit), `--no-contains` inverts it. With `--merged`, only branches merged into the named
 commit (i.e. the branches whose tip commits are reachable from the named
 commit) will be listed.  With `--no-merged` only branches not merged into
 the named commit will be listed.  If the <commit> argument is missing it
@@ -213,6 +214,10 @@ start-point is either a local or remote-tracking branch.
 	Only list branches which contain the specified commit (HEAD
 	if not specified). Implies `--list`.
 
+--no-contains [<commit>]::
+	Only list branches which don't contain the specified commit
+	(HEAD if not specified). Implies `--list`.
+
 --merged [<commit>]::
 	Only list branches whose tips are reachable from the
 	specified commit (HEAD if not specified). Implies `--list`,
@@ -298,13 +303,16 @@ If you are creating a branch that you want to checkout immediately, it is
 easier to use the git checkout command with its `-b` option to create
 a branch and check it out with a single command.
 
-The options `--contains`, `--merged` and `--no-merged` serve three related
-but different purposes:
+The options `--contains`, `--no-contains`, `--merged` and `--no-merged`
+serve four related but different purposes:
 
 - `--contains <commit>` is used to find all branches which will need
   special attention if <commit> were to be rebased or amended, since those
   branches contain the specified <commit>.
 
+- `--no-contains <commit>` is the inverse of that, i.e. branches that don't
+  contain the specified <commit>.
+
 - `--merged` is used to find all branches which can be safely deleted,
   since those branches are fully contained by HEAD.
 

Documentation/git-for-each-ref.txt

@@ -11,7 +11,7 @@ SYNOPSIS
 'git for-each-ref' [--count=<count>] [--shell|--perl|--python|--tcl]
 		   [(--sort=<key>)...] [--format=<format>] [<pattern>...]
 		   [--points-at <object>] [(--merged | --no-merged) [<object>]]
-		   [--contains [<object>]]
+		   [--contains [<object>]] [--no-contains [<object>]]
 
 DESCRIPTION
 -----------
@@ -81,6 +81,10 @@ OPTIONS
 	Only list refs which contain the specified commit (HEAD if not
 	specified).
 
+--no-contains [<object>]::
+	Only list refs which don't contain the specified commit (HEAD
+	if not specified).
+
 --ignore-case::
 	Sorting and filtering refs are case insensitive.
 

Documentation/git-tag.txt

@@ -12,7 +12,7 @@ SYNOPSIS
 'git tag' [-a | -s | -u <keyid>] [-f] [-m <msg> | -F <file>]
 	<tagname> [<commit> | <object>]
 'git tag' -d <tagname>...
-'git tag' [-n[<num>]] -l [--contains <commit>] [--points-at <object>]
+'git tag' [-n[<num>]] -l [--contains <commit>] [--contains <commit>] [--points-at <object>]
 	[--column[=<options>] | --no-column] [--create-reflog] [--sort=<key>]
 	[--format=<format>] [--[no-]merged [<commit>]] [<pattern>...]
 'git tag' -v [--format=<format>] <tagname>...
@@ -130,6 +130,10 @@ This option is only applicable when listing tags without annotation lines.
 	Only list tags which contain the specified commit (HEAD if not
 	specified). Implies `--list`.
 
+--no-contains [<commit>]::
+	Only list tags which don't contain the specified commit (HEAD if
+	not specified). Implies `--list`.
+
 --merged [<commit>]::
 	Only list tags whose commits are reachable from the specified
 	commit (`HEAD` if not specified), incompatible with `--no-merged`.

builtin/branch.c

@@ -548,7 +548,9 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 		OPT_SET_INT('r', "remotes",     &filter.kind, N_("act on remote-tracking branches"),
 			FILTER_REFS_REMOTES),
 		OPT_CONTAINS(&filter.with_commit, N_("print only branches that contain the commit")),
+		OPT_NO_CONTAINS(&filter.no_commit, N_("print only branches that don't contain the commit")),
 		OPT_WITH(&filter.with_commit, N_("print only branches that contain the commit")),
+		OPT_WITHOUT(&filter.no_commit, N_("print only branches that don't contain the commit")),
 		OPT__ABBREV(&filter.abbrev),
 
 		OPT_GROUP(N_("Specific git-branch actions:")),
@@ -604,7 +606,8 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 	if (!delete && !rename && !edit_description && !new_upstream && !unset_upstream && argc == 0)
 		list = 1;
 
-	if (filter.with_commit || filter.merge != REF_FILTER_MERGED_NONE || filter.points_at.nr)
+	if (filter.with_commit || filter.merge != REF_FILTER_MERGED_NONE || filter.points_at.nr ||
+	    filter.no_commit)
 		list = 1;
 
 	if (!!delete + !!rename + !!new_upstream +

builtin/for-each-ref.c

@@ -9,7 +9,7 @@ static char const * const for_each_ref_usage[] = {
 	N_("git for-each-ref [<options>] [<pattern>]"),
 	N_("git for-each-ref [--points-at <object>]"),
 	N_("git for-each-ref [(--merged | --no-merged) [<commit>]]"),
-	N_("git for-each-ref [--contains [<commit>]]"),
+	N_("git for-each-ref [--contains [<commit>]] [--no-contains [<commit>]]"),
 	NULL
 };
 
@@ -43,6 +43,7 @@ int cmd_for_each_ref(int argc, const char **argv, const char *prefix)
 		OPT_MERGED(&filter, N_("print only refs that are merged")),
 		OPT_NO_MERGED(&filter, N_("print only refs that are not merged")),
 		OPT_CONTAINS(&filter.with_commit, N_("print only refs which contain the commit")),
+		OPT_NO_CONTAINS(&filter.no_commit, N_("print only refs which don't contain the commit")),
 		OPT_BOOL(0, "ignore-case", &icase, N_("sorting and filtering are case insensitive")),
 		OPT_END(),
 	};

builtin/tag.c

@@ -22,7 +22,7 @@
 static const char * const git_tag_usage[] = {
 	N_("git tag [-a | -s | -u <key-id>] [-f] [-m <msg> | -F <file>] <tagname> [<head>]"),
 	N_("git tag -d <tagname>..."),
-	N_("git tag -l [-n[<num>]] [--contains <commit>] [--points-at <object>]"
+	N_("git tag -l [-n[<num>]] [--contains <commit>] [--no-contains <commit>] [--points-at <object>]"
 		"\n\t\t[--format=<format>] [--[no-]merged [<commit>]] [<pattern>...]"),
 	N_("git tag -v [--format=<format>] <tagname>..."),
 	NULL
@@ -424,7 +424,9 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		OPT_GROUP(N_("Tag listing options")),
 		OPT_COLUMN(0, "column", &colopts, N_("show tag list in columns")),
 		OPT_CONTAINS(&filter.with_commit, N_("print only tags that contain the commit")),
+		OPT_NO_CONTAINS(&filter.no_commit, N_("print only tags that don't contain the commit")),
 		OPT_WITH(&filter.with_commit, N_("print only tags that contain the commit")),
+		OPT_WITHOUT(&filter.no_commit, N_("print only tags that don't contain the commit")),
 		OPT_MERGED(&filter, N_("print only tags that are merged")),
 		OPT_NO_MERGED(&filter, N_("print only tags that are not merged")),
 		OPT_CALLBACK(0 , "sort", sorting_tail, N_("key"),
@@ -458,7 +460,7 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 	if (!cmdmode) {
 		if (argc == 0)
 			cmdmode = 'l';
-		else if (filter.with_commit ||
+		else if (filter.with_commit || filter.no_commit ||
 			 filter.points_at.nr || filter.merge_commit ||
 			 filter.lines != -1)
 			cmdmode = 'l';
@@ -495,6 +497,8 @@ int cmd_tag(int argc, const char **argv, const char *prefix)
 		die(_("-n option is only allowed in list mode"));
 	if (filter.with_commit)
 		die(_("--contains option is only allowed in list mode"));
+	if (filter.no_commit)
+		die(_("--no-contains option is only allowed in list mode"));
 	if (filter.points_at.nr)
 		die(_("--points-at option is only allowed in list mode"));
 	if (filter.merge_commit)

contrib/completion/git-completion.bash

@@ -1093,7 +1093,7 @@ _git_branch ()
 	--*)
 		__gitcomp "
 			--color --no-color --verbose --abbrev= --no-abbrev
-			--track --no-track --contains --merged --no-merged
+			--track --no-track --contains --no-contains --merged --no-merged
 			--set-upstream-to= --edit-description --list
 			--unset-upstream --delete --move --remotes
 			--column --no-column --sort= --points-at
@@ -2862,7 +2862,7 @@ _git_tag ()
 		__gitcomp "
 			--list --delete --verify --annotate --message --file
 			--sign --cleanup --local-user --force --column --sort=
-			--contains --points-at --merged --no-merged --create-reflog
+			--contains --no-contains --points-at --merged --no-merged --create-reflog
 			"
 		;;
 	esac

parse-options.h

@@ -259,6 +259,8 @@ extern int parse_opt_passthru_argv(const struct option *, const char *, int);
 	  parse_opt_commits, (intptr_t) "HEAD" \
 	}
 #define OPT_CONTAINS(v, h) _OPT_CONTAINS_OR_WITH("contains", v, h, PARSE_OPT_NONEG)
+#define OPT_NO_CONTAINS(v, h) _OPT_CONTAINS_OR_WITH("no-contains", v, h, PARSE_OPT_NONEG)
 #define OPT_WITH(v, h) _OPT_CONTAINS_OR_WITH("with", v, h, PARSE_OPT_HIDDEN | PARSE_OPT_NONEG)
+#define OPT_WITHOUT(v, h) _OPT_CONTAINS_OR_WITH("without", v, h, PARSE_OPT_HIDDEN | PARSE_OPT_NONEG)
 
 #endif

ref-filter.c

@@ -1487,6 +1487,7 @@ struct ref_filter_cbdata {
 	struct ref_array *array;
 	struct ref_filter *filter;
 	struct contains_cache contains_cache;
+	struct contains_cache no_contains_cache;
 };
 
 /*
@@ -1586,11 +1587,11 @@ static enum contains_result contains_tag_algo(struct commit *candidate,
 }
 
 static int commit_contains(struct ref_filter *filter, struct commit *commit,
-			   struct contains_cache *cache)
+			   struct commit_list *list, struct contains_cache *cache)
 {
 	if (filter->with_commit_tag_algo)
-		return contains_tag_algo(commit, filter->with_commit, cache) == CONTAINS_YES;
-	return is_descendant_of(commit, filter->with_commit);
+		return contains_tag_algo(commit, list, cache) == CONTAINS_YES;
+	return is_descendant_of(commit, list);
 }
 
 /*
@@ -1780,13 +1781,17 @@ static int ref_filter_handler(const char *refname, const struct object_id *oid,
 	 * obtain the commit using the 'oid' available and discard all
 	 * non-commits early. The actual filtering is done later.
 	 */
-	if (filter->merge_commit || filter->with_commit || filter->verbose) {
+	if (filter->merge_commit || filter->with_commit || filter->no_commit || filter->verbose) {
 		commit = lookup_commit_reference_gently(oid->hash, 1);
 		if (!commit)
 			return 0;
-		/* We perform the filtering for the '--contains' option */
+		/* We perform the filtering for the '--contains' option... */
 		if (filter->with_commit &&
-		    !commit_contains(filter, commit, &ref_cbdata->contains_cache))
+		    !commit_contains(filter, commit, filter->with_commit, &ref_cbdata->contains_cache))
+			return 0;
+		/* ...or for the `--no-contains' option */
+		if (filter->no_commit &&
+		    commit_contains(filter, commit, filter->no_commit, &ref_cbdata->no_contains_cache))
 			return 0;
 	}
 
@@ -1887,6 +1892,7 @@ int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
 	filter->kind = type & FILTER_REFS_KIND_MASK;
 
 	init_contains_cache(&ref_cbdata.contains_cache);
+	init_contains_cache(&ref_cbdata.no_contains_cache);
 
 	/*  Simple per-ref filtering */
 	if (!filter->kind)
@@ -1911,6 +1917,7 @@ int filter_refs(struct ref_array *array, struct ref_filter *filter, unsigned int
 	}
 
 	clear_contains_cache(&ref_cbdata.contains_cache);
+	clear_contains_cache(&ref_cbdata.no_contains_cache);
 
 	/*  Filters that need revision walking */
 	if (filter->merge_commit)

ref-filter.h

@@ -53,6 +53,7 @@ struct ref_filter {
 	const char **name_patterns;
 	struct sha1_array points_at;
 	struct commit_list *with_commit;
+	struct commit_list *no_commit;
 
 	enum {
 		REF_FILTER_MERGED_NONE = 0,