[PATCH v4 5/6] rev-list: add list-objects filtering support

[Jeff Hostetler <git@jeffhostetler.com>]

From: Jeff Hostetler <jeffhost@microsoft.com>

Teach rev-list to use the filtering provided by the
traverse_commit_list_filtered() interface to omit
unwanted objects from the result.  This feature is
intended to help with partial clone.

Object filtering is only allowed when one of the "--objects*"
options are used.

When the "--filter-print-omitted" option is used, the omitted
objects are printed at the end.  These are marked with a "~".
This option can be combined with "--quiet" to get a list of
just the omitted objects.

Added "--missing=(error|print|omit)" argument to specify how
rev-list should behave when it encounters a missing object
(presumably from a prior partial clone).

When "--missing=print" is used, rev-list will print a list of
any missing objects that should have been included in the output.
These are marked with a "?".

Add t6112 test.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 Documentation/git-rev-list.txt      |   4 +-
 Documentation/rev-list-options.txt  |  37 ++++++
 builtin/rev-list.c                  | 108 ++++++++++++++++-
 t/t6112-rev-list-filters-objects.sh | 225 ++++++++++++++++++++++++++++++++++++
 4 files changed, 371 insertions(+), 3 deletions(-)
 create mode 100755 t/t6112-rev-list-filters-objects.sh

diff --git a/Documentation/git-rev-list.txt b/Documentation/git-rev-list.txt
index ef22f17..397a0dd 100644
--- a/Documentation/git-rev-list.txt
+++ b/Documentation/git-rev-list.txt
@@ -47,7 +47,9 @@ SYNOPSIS
 	     [ --fixed-strings | -F ]
 	     [ --date=<format>]
 	     [ [ --objects | --objects-edge | --objects-edge-aggressive ]
-	       [ --unpacked ] ]
+	       [ --unpacked ]
+	       [ --filter=<filter-spec> [ --filter-print-omitted ] ] ]
+	     [ --missing=(error|allow-any|print) ]
 	     [ --pretty | --header ]
 	     [ --bisect ]
 	     [ --bisect-vars ]
diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index 13501e1..c84e465 100644
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt
@@ -706,6 +706,43 @@ ifdef::git-rev-list[]
 --unpacked::
 	Only useful with `--objects`; print the object IDs that are not
 	in packs.
+
+--filter=<filter-spec>::
+	Only useful with one of the `--objects*`; omits objects (usually
+	blobs) from the list of printed objects.  The '<filter-spec>'
+	may be one of the following:
++
+The form '--filter=blob:none' omits all blobs.
++
+The form '--filter=blob:limit=<n>[kmg]' omits blobs larger than n bytes
+or units.  The value may be zero.  Special files matching '.git*' are
+alwayse included, regardless of size.
++
+The form '--filter=sparse:oid=<oid-ish>' uses a sparse-checkout
+specification contained in the object (or the object that the expression
+evaluates to) to omit blobs not required by the corresponding sparse
+checkout.
++
+The form '--filter=sparse:path=<path>' similarly uses a sparse-checkout
+specification contained in <path>.
+
+--filter-print-omitted::
+	Only useful with `--filter=`; prints a list of the omitted objects.
+	Object IDs are prefixed with a ``~'' character.
+
+--missing=(error|allow-any|print)::
+	Specifies how missing objects are handled.  The repository may
+	have missing objects after a partial clone, for example.
++
+The value 'error' requests that rev-list stop with an error if a missing
+object is encountered.  This is the default action.
++
+The value 'allow-any' will allow object traversal to continue if a
+missing object is encountered.  Missing objects will silently be omitted
+from the results.
++
+The value 'print' is like 'allow-any', but will also print a list of the
+missing objects.  Object IDs are prefixed with a ``?'' character.
 endif::git-rev-list[]
 
 --no-walk[=(sorted|unsorted)]::
diff --git a/builtin/rev-list.c b/builtin/rev-list.c
index c1c74d4..da4a39b 100644
--- a/builtin/rev-list.c
+++ b/builtin/rev-list.c
@@ -4,6 +4,8 @@
 #include "diff.h"
 #include "revision.h"
 #include "list-objects.h"
+#include "list-objects-filter.h"
+#include "list-objects-filter-options.h"
 #include "pack.h"
 #include "pack-bitmap.h"
 #include "builtin.h"
@@ -12,6 +14,7 @@
 #include "bisect.h"
 #include "progress.h"
 #include "reflog-walk.h"
+#include "oidset.h"
 
 static const char rev_list_usage[] =
 "git rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
@@ -55,6 +58,20 @@ static const char rev_list_usage[] =
 static struct progress *progress;
 static unsigned progress_counter;
 
+static struct list_objects_filter_options filter_options;
+static struct oidset omitted_objects;
+static int arg_print_omitted; /* print objects omitted by filter */
+
+static struct oidset missing_objects;
+enum missing_action {
+	MA_ERROR = 0,    /* fail if any missing objects are encountered */
+	MA_ALLOW_ANY,    /* silently allow ALL missing objects */
+	MA_PRINT,        /* print ALL missing objects in special section */
+};
+static enum missing_action arg_missing_action;
+
+#define DEFAULT_OIDSET_SIZE     (16*1024)
+
 static void finish_commit(struct commit *commit, void *data);
 static void show_commit(struct commit *commit, void *data)
 {
@@ -178,11 +195,31 @@ static void finish_commit(struct commit *commit, void *data)
 	free_commit_buffer(commit);
 }
 
+static inline void finish_object__ma(struct object *obj)
+{
+	switch (arg_missing_action) {
+	case MA_ERROR:
+		die("missing blob object '%s'", oid_to_hex(&obj->oid));
+		return;
+
+	case MA_ALLOW_ANY:
+		return;
+
+	case MA_PRINT:
+		oidset_insert(&missing_objects, &obj->oid);
+		return;
+
+	default:
+		BUG("unhandled missing_action");
+		return;
+	}
+}
+
 static void finish_object(struct object *obj, const char *name, void *cb_data)
 {
 	struct rev_list_info *info = cb_data;
 	if (obj->type == OBJ_BLOB && !has_object_file(&obj->oid))
-		die("missing blob object '%s'", oid_to_hex(&obj->oid));
+		finish_object__ma(obj);
 	if (info->revs->verify_objects && !obj->parsed && obj->type != OBJ_COMMIT)
 		parse_object(&obj->oid);
 }
@@ -269,6 +306,26 @@ static int show_object_fast(
 	return 1;
 }
 
+static inline int parse_missing_action_value(const char *value)
+{
+	if (!strcmp(value, "error")) {
+		arg_missing_action = MA_ERROR;
+		return 1;
+	}
+
+	if (!strcmp(value, "allow-any")) {
+		arg_missing_action = MA_ALLOW_ANY;
+		return 1;
+	}
+
+	if (!strcmp(value, "print")) {
+		arg_missing_action = MA_PRINT;
+		return 1;
+	}
+
+	return 0;
+}
+
 int cmd_rev_list(int argc, const char **argv, const char *prefix)
 {
 	struct rev_info revs;
@@ -335,6 +392,26 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 			show_progress = arg;
 			continue;
 		}
+
+		if (skip_prefix(arg, ("--" CL_ARG__FILTER "="), &arg)) {
+			parse_list_objects_filter(&filter_options, arg);
+			if (filter_options.choice && !revs.blob_objects)
+				die(_("object filtering requires --objects"));
+			if (filter_options.choice == LOFC_SPARSE_OID &&
+			    !filter_options.sparse_oid_value)
+				die(_("invalid sparse value '%s'"),
+				    filter_options.raw_value);
+			continue;
+		}
+		if (!strcmp(arg, "--filter-print-omitted")) {
+			arg_print_omitted = 1;
+			continue;
+		}
+
+		if (skip_prefix(arg, "--missing=", &arg) &&
+		    parse_missing_action_value(arg))
+			continue;
+		
 		usage(rev_list_usage);
 
 	}
@@ -360,6 +437,9 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 	if (revs.show_notes)
 		die(_("rev-list does not support display of notes"));
 
+	if (filter_options.choice && use_bitmap_index)
+		die(_("cannot combine --use-bitmap-index with object filtering"));
+
 	save_commit_buffer = (revs.verbose_header ||
 			      revs.grep_filter.pattern_list ||
 			      revs.grep_filter.header_list);
@@ -404,7 +484,31 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 			return show_bisect_vars(&info, reaches, all);
 	}
 
-	traverse_commit_list(&revs, show_commit, show_object, &info);
+	if (arg_print_omitted)
+		oidset_init(&omitted_objects, DEFAULT_OIDSET_SIZE);
+	if (arg_missing_action == MA_PRINT)
+		oidset_init(&missing_objects, DEFAULT_OIDSET_SIZE);
+
+	traverse_commit_list_filtered(
+		&filter_options, &revs, show_commit, show_object, &info,
+		(arg_print_omitted ? &omitted_objects : NULL));
+
+	if (arg_print_omitted) {
+		struct oidset_iter iter;
+		struct object_id *oid;
+		oidset_iter_init(&omitted_objects, &iter);
+		while ((oid = oidset_iter_next(&iter)))
+			printf("~%s\n", oid_to_hex(oid));
+		oidset_clear(&omitted_objects);
+	}
+	if (arg_missing_action == MA_PRINT) {
+		struct oidset_iter iter;
+		struct object_id *oid;
+		oidset_iter_init(&missing_objects, &iter);
+		while ((oid = oidset_iter_next(&iter)))
+			printf("?%s\n", oid_to_hex(oid));
+		oidset_clear(&missing_objects);
+	}
 
 	stop_progress(&progress);
 
diff --git a/t/t6112-rev-list-filters-objects.sh b/t/t6112-rev-list-filters-objects.sh
new file mode 100755
index 0000000..73166db
--- /dev/null
+++ b/t/t6112-rev-list-filters-objects.sh
@@ -0,0 +1,225 @@
+#!/bin/sh
+
+test_description='git rev-list with object filtering for partial clone'
+
+. ./test-lib.sh
+
+# Test the blob:none filter.
+
+test_expect_success 'setup r1' '
+	echo "{print \$1}" >print_1.awk &&
+	echo "{print \$2}" >print_2.awk &&
+
+	git init r1 &&
+	for n in 1 2 3 4 5
+	do
+		echo "This is file: $n" > r1/file.$n
+		git -C r1 add file.$n
+		git -C r1 commit -m "$n"
+	done
+'
+
+test_expect_success 'verify blob:none omits all 5 blobs' '
+	git -C r1 ls-files -s file.1 file.2 file.3 file.4 file.5 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	git -C r1 rev-list HEAD --quiet --objects --filter-print-omitted --filter=blob:none \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+test_expect_success 'verify emitted+omitted == all' '
+	git -C r1 rev-list HEAD --objects \
+		| awk -f print_1.awk \
+		| sort >expected &&
+	git -C r1 rev-list HEAD --objects --filter-print-omitted --filter=blob:none \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+
+# Test blob:limit=<n>[kmg] filter.
+# We boundary test around the size parameter.  The filter is strictly less than
+# the value, so size 500 and 1000 should have the same results, but 1001 should
+# filter more.
+
+test_expect_success 'setup r2' '
+	git init r2 &&
+	for n in 1000 10000
+	do
+		printf "%"$n"s" X > r2/large.$n
+		git -C r2 add large.$n
+		git -C r2 commit -m "$n"
+	done
+'
+
+test_expect_success 'verify blob:limit=500 omits all blobs' '
+	git -C r2 ls-files -s large.1000 large.10000 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	git -C r2 rev-list HEAD --quiet --objects --filter-print-omitted --filter=blob:limit=500 \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+test_expect_success 'verify emitted+omitted == all' '
+	git -C r2 rev-list HEAD --objects \
+		| awk -f print_1.awk \
+		| sort >expected &&
+	git -C r2 rev-list HEAD --objects --filter-print-omitted --filter=blob:limit=500 \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+test_expect_success 'verify blob:limit=1000' '
+	git -C r2 ls-files -s large.1000 large.10000 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	git -C r2 rev-list HEAD --quiet --objects --filter-print-omitted --filter=blob:limit=1000 \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+test_expect_success 'verify blob:limit=1001' '
+	git -C r2 ls-files -s large.10000 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	git -C r2 rev-list HEAD --quiet --objects --filter-print-omitted --filter=blob:limit=1001 \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+test_expect_success 'verify blob:limit=1k' '
+	git -C r2 ls-files -s large.10000 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	git -C r2 rev-list HEAD --quiet --objects --filter-print-omitted --filter=blob:limit=1k \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+test_expect_success 'verify blob:limit=1m' '
+	cat </dev/null >expected &&
+	git -C r2 rev-list HEAD --quiet --objects --filter-print-omitted --filter=blob:limit=1m \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+# Test sparse:path=<path> filter.
+# Use a local file containing a sparse-checkout specification to filter
+# out blobs not required for the corresponding sparse-checkout.  We do not
+# require sparse-checkout to actually be enabled.
+
+test_expect_success 'setup r3' '
+	git init r3 &&
+	mkdir r3/dir1 &&
+	for n in sparse1 sparse2
+	do
+		echo "This is file: $n" > r3/$n
+		git -C r3 add $n
+		echo "This is file: dir1/$n" > r3/dir1/$n
+		git -C r3 add dir1/$n
+	done &&
+	git -C r3 commit -m "sparse" &&
+	echo dir1/ >pattern1 &&
+	echo sparse1 >pattern2
+'
+
+test_expect_success 'verify sparse:path=pattern1 omits top-level files' '
+	git -C r3 ls-files -s sparse1 sparse2 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	git -C r3 rev-list HEAD --quiet --objects --filter-print-omitted --filter=sparse:path=../pattern1 \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+test_expect_success 'verify sparse:path=pattern2 omits both sparse2 files' '
+	git -C r3 ls-files -s sparse2 dir1/sparse2 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	git -C r3 rev-list HEAD --quiet --objects --filter-print-omitted --filter=sparse:path=../pattern2 \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+# Test sparse:oid=<oid-ish> filter.
+# Like sparse:path, but we get the sparse-checkout specification from
+# a blob rather than a file on disk.
+
+test_expect_success 'setup r3 part 2' '
+	echo dir1/ >r3/pattern &&
+	git -C r3 add pattern &&
+	git -C r3 commit -m "pattern"
+'
+
+test_expect_success 'verify sparse:oid=OID omits top-level files' '
+	git -C r3 ls-files -s pattern sparse1 sparse2 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	oid=$(git -C r3 ls-files -s pattern | awk -f print_2.awk) &&
+	git -C r3 rev-list HEAD --quiet --objects --filter-print-omitted --filter=sparse:oid=$oid \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+test_expect_success 'verify sparse:oid=oid-ish omits top-level files' '
+	git -C r3 ls-files -s pattern sparse1 sparse2 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	git -C r3 rev-list HEAD --quiet --objects --filter-print-omitted --filter=sparse:oid=master:pattern \
+		| awk -f print_1.awk \
+		| sed "s/~//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+# Delete some loose objects and use rev-list, but WITHOUT any filtering.
+# This models previously omitted objects that we did not receive.
+
+test_expect_success 'rev-list W/ --missing=print' '
+	git -C r1 ls-files -s file.1 file.2 file.3 file.4 file.5 \
+		| awk -f print_2.awk \
+		| sort >expected &&
+	for id in `cat expected | sed "s|..|&/|"`
+	do
+		rm r1/.git/objects/$id
+	done &&
+	git -C r1 rev-list --quiet HEAD --missing=print --objects \
+		| awk -f print_1.awk \
+		| sed "s/?//" \
+		| sort >observed &&
+	test_cmp observed expected
+'
+
+test_expect_success 'rev-list W/O --missing fails' '
+	test_must_fail git -C r1 rev-list --quiet --objects HEAD
+'
+
+test_expect_success 'rev-list W/ missing=allow-any' '
+	git -C r1 rev-list --quiet --missing=allow-any --objects HEAD
+'
+
+test_done
-- 
2.9.3