[PATCH 2/2] fast-export: Add a --full-tree option

[Elijah Newren <newren@gmail.com>]

This option can be useful when doing incremental exports/imports when
later runs of fast-export are passed a larger list of PATHs (for
limiting what to export) than prior runs did.

It's also useful for working around potential bugs in prior incremental
exports/imports, such as fast-import ignoring symlinks that used to be
directories.

Signed-off-by: Elijah Newren <newren@gmail.com>
---
 Documentation/git-fast-export.txt |   11 +++++++++++
 builtin/fast-export.c             |    8 +++++++-
 t/t9350-fast-export.sh            |   35 +++++++++++++++++++++++++++++++++++
 3 files changed, 53 insertions(+), 1 deletions(-)

diff --git a/Documentation/git-fast-export.txt b/Documentation/git-fast-export.txt
index 98ec6b5..5202501 100644
--- a/Documentation/git-fast-export.txt
+++ b/Documentation/git-fast-export.txt
@@ -90,6 +90,17 @@ marks the same across runs.
 	resulting stream can only be used by a repository which
 	already contains the necessary objects.
 
+--full-tree::
+	By default, for each commit that has a parent, only the files
+	that are different between the commit and its parent are
+	shown.  By using --full-tree, a "deleteall" directive will be
+	sent out with each commit followed by a listing of all files
+	contained in the commit.  This can be useful when doing
+	incremental exports/imports (making use of --export-marks and
+	--import-marks) when later runs of fast-export contain a
+	larger list of PATH limiters in [git-rev-list-args...] than
+	previous runs do.
+
 [git-rev-list-args...]::
        A list of arguments, acceptable to 'git rev-parse' and
        'git rev-list', that specifies the specific objects and references
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index c6dd71a..d30bed8 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -26,6 +26,7 @@ static int progress;
 static enum { ABORT, VERBATIM, WARN, STRIP } signed_tag_mode = ABORT;
 static enum { ERROR, DROP, REWRITE } tag_of_filtered_mode = ABORT;
 static int fake_missing_tagger;
+static int full_tree;
 static int no_data;
 
 static int parse_opt_signed_tag_mode(const struct option *opt,
@@ -241,7 +242,8 @@ static void handle_commit(struct commit *commit, struct rev_info *rev)
 		message += 2;
 
 	if (commit->parents &&
-	    get_object_mark(&commit->parents->item->object) != 0) {
+	    get_object_mark(&commit->parents->item->object) != 0 &&
+	    !full_tree) {
 		parse_commit(commit->parents->item);
 		diff_tree_sha1(commit->parents->item->tree->object.sha1,
 			       commit->tree->object.sha1, "", &rev->diffopt);
@@ -281,6 +283,8 @@ static void handle_commit(struct commit *commit, struct rev_info *rev)
 		i++;
 	}
 
+	if (full_tree)
+		printf("deleteall\n");
 	log_tree_diff_flush(rev);
 	rev->diffopt.output_format = saved_output_format;
 
@@ -584,6 +588,8 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
 			     "Import marks from this file"),
 		OPT_BOOLEAN(0, "fake-missing-tagger", &fake_missing_tagger,
 			     "Fake a tagger when tags lack one"),
+		OPT_BOOLEAN(0, "full-tree", &full_tree,
+			     "Output full tree for each commit"),
 		{ OPTION_NEGBIT, 0, "data", &no_data, NULL,
 			"Skip output of blob data",
 			PARSE_OPT_NOARG | PARSE_OPT_NEGHELP, NULL, 1 },
diff --git a/t/t9350-fast-export.sh b/t/t9350-fast-export.sh
index 1ee1461..05c79ea 100755
--- a/t/t9350-fast-export.sh
+++ b/t/t9350-fast-export.sh
@@ -400,4 +400,39 @@ test_expect_success 'directory becomes symlink'        '
 	(cd result && git show master:foo)
 '
 
+cat >> dirtosymlink/expected << EOF
+blob
+mark :5
+data 6
+hello
+
+blob
+mark :6
+data 7
+badlink
+commit refs/heads/master
+mark :7
+author A U Thor <author@example.com> 1112912713 -0700
+committer C O Mitter <committer@example.com> 1112912713 -0700
+data 6
+three
+from :4
+deleteall
+M 100644 :5 bar/world
+M 120000 :6 foo
+
+EOF
+
+test_expect_success 'full-tree'        '
+	(
+		cd dirtosymlink &&
+		git fast-export --export-marks=marks master -- foo > output1 &&
+		rm foo &&
+		ln -s badlink foo &&
+		git commit -mthree foo &&
+		git fast-export --import-marks=marks --full-tree master -- foo bar > output &&
+		test_cmp output expected
+	)
+'
+
 test_done
-- 
1.6.6.1