rev-list: move --filter parsing into revision.c

Now that 'struct rev_info' has a 'filter' member and most consumers of
object filtering are using that member instead of an external struct,
move the parsing of the '--filter' option out of builtin/rev-list.c and
into revision.c.

This use within handle_revision_pseudo_opt() allows us to find the
option within setup_revisions() if the arguments are passed directly. In
the case of a command such as 'git blame', the arguments are first
scanned and checked with parse_revision_opt(), which complains about the
option, so 'git blame --filter=blob:none <file>' does not become valid
with this change.

Some commands, such as 'git diff' gain this option without having it
make an effect. And 'git diff --objects' was already possible, but does
not actually make sense in that builtin.

The key addition that is coming is 'git bundle create --filter=<X>' so
we can create bundles containing promisor packs. More work is required
to make them fully functional, but that will follow.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/revision.c b/revision.c
index 4c55c55..58b8717 100644
--- a/revision.c
+++ b/revision.c
@@ -32,6 +32,7 @@
 #include "utf8.h"
 #include "bloom.h"
 #include "json-writer.h"
+#include "list-objects-filter-options.h"
 
 volatile show_early_output_fn_t show_early_output;
 
@@ -2690,6 +2691,10 @@ static int handle_revision_pseudo_opt(struct rev_info *revs,
 		revs->no_walk = 0;
 	} else if (!strcmp(arg, "--single-worktree")) {
 		revs->single_worktree = 1;
+	} else if (skip_prefix(arg, ("--" CL_ARG__FILTER "="), &arg)) {
+		parse_list_objects_filter(&revs->filter, arg);
+	} else if (!strcmp(arg, ("--no-" CL_ARG__FILTER))) {
+		list_objects_filter_set_no_filter(&revs->filter);
 	} else {
 		return 0;
 	}
@@ -2894,6 +2899,8 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, struct s
 		die("cannot combine --walk-reflogs with history-limiting options");
 	if (revs->rewrite_parents && revs->children.name)
 		die(_("options '%s' and '%s' cannot be used together"), "--parents", "--children");
+	if (revs->filter.choice && !revs->blob_objects)
+		die(_("object filtering requires --objects"));
 
 	/*
 	 * Limitations on the graph functionality