[PATCH 2/2] archive: handle commits with an empty tree
git-archive relies on get_pathspec to convert its argv into a list of pathspecs. When get_pathspec is given an empty argv list, it returns a single pathspec, the empty string, to indicate that everything matches. When we feed this to our path_exists function, we typically see that the pathspec turns up at least one item in the tree, and we are happy.
But when our tree is empty, we erroneously think it is because the pathspec is too limited, when in fact it is simply that there is nothing to be found in the tree. This is a weird corner case, but the correct behavior is almost certainly to produce an empty archive, not to exit with an error.
This patch teaches git-archive to create empty archives when there is no pathspec given (we continue to complain if a pathspec is given, since it obviously is not matched). It also confirms that the tar and zip writers produce sane output in this instance.
Signed-off-by: Jeff King <peff@peff.net>
---
archive.c | 2 +-
t/t5004-archive-corner-cases.sh | 83 ++++++++++++++++++++++++++++++++++++++++
t/t5004/empty.zip | Bin 0 -> 62 bytes
3 files changed, 84 insertions(+), 1 deletion(-)
create mode 100755 t/t5004-archive-corner-cases.sh
create mode 100644 t/t5004/empty.zip
Show changes to 3 files +84 −1
archive.c, t/t5004-archive-corner-cases.sh, t/t5004/empty.zip
diff --git a/archive.c b/archive.c
index 93e00bb..d254fa5 100644
--- a/archive.c
+++ b/archive.c
@@ -234,7 +234,7 @@ static void parse_pathspec_arg(const char **pathspec,
ar_args->pathspec = pathspec = get_pathspec("", pathspec);
if (pathspec) {
while (*pathspec) {
- if (!path_exists(ar_args->tree, *pathspec))
+ if (**pathspec && !path_exists(ar_args->tree, *pathspec))
die("path not found: %s", *pathspec);
pathspec++;
}
diff --git a/t/t5004-archive-corner-cases.sh b/t/t5004-archive-corner-cases.sh
new file mode 100755
index 0000000..395dd58
--- /dev/null
+++ b/t/t5004-archive-corner-cases.sh
@@ -0,0 +1,83 @@
+#!/bin/sh
+
+test_description='test corner cases of git-archive'
+. ./test-lib.sh
+
+test_expect_success 'create commit with empty tree' '
+ git commit --allow-empty -m foo
+'
+
+# Make a dir and clean it up afterwards
+make_dir() {
+ mkdir "$1" &&
+ test_when_finished "rm -rf '$1'"
+}
+
+# Check that the dir given in "$1" contains exactly the
+# set of paths given as arguments.
+check_dir() {
+ dir=$1; shift
+ {
+ echo "$dir" &&
+ for i in "$@"; do
+ echo "$dir/$i"
+ done
+ } | sort >expect &&
+ find "$dir" -print | sort >actual &&
+ test_cmp expect actual
+}
+
+test_expect_success 'tar archive of empty tree is empty' '
+ git archive --format=tar HEAD >empty.tar &&
+ make_dir extract &&
+ "$TAR" xf empty.tar -C extract &&
+ check_dir extract
+'
+
+test_expect_success 'tar archive of empty tree with prefix' '
+ git archive --format=tar --prefix=foo/ HEAD >prefix.tar &&
+ make_dir extract &&
+ "$TAR" xf prefix.tar -C extract &&
+ check_dir extract foo
+'
+
+test_expect_success UNZIP 'zip archive of empty tree is empty' '
+ # Detect the exit code produced when our particular flavor of unzip
+ # sees an empty archive. Infozip will generate a warning and exit with
+ # code 1. But in the name of sanity, we do not expect other unzip
+ # implementations to do the same thing (it would be perfectly
+ # reasonable to exit 0, for example).
+ #
+ # This makes our test less rigorous on some platforms (unzip may not
+ # handle the empty repo at all, making our later check of its exit code
+ # a no-op). But we cannot do anything reasonable except skip the test
+ # on such platforms anyway, and this is the moral equivalent.
+ "$GIT_UNZIP" "$TEST_DIRECTORY"/t5004/empty.zip
+ expect_code=$?
+
+ git archive --format=zip HEAD >empty.zip &&
+ make_dir extract &&
+ (
+ cd extract &&
+ test_expect_code $expect_code "$GIT_UNZIP" ../empty.zip
+ ) &&
+ check_dir extract
+'
+
+test_expect_success UNZIP 'zip archive of empty tree with prefix' '
+ # We do not have to play exit-code tricks here, because our
+ # result should not be empty; it has a directory in it.
+ git archive --format=zip --prefix=foo/ HEAD >prefix.zip &&
+ make_dir extract &&
+ (
+ cd extract &&
+ "$GIT_UNZIP" ../prefix.zip
+ ) &&
+ check_dir extract foo
+'
+
+test_expect_success 'archive complains about pathspec on empty tree' '
+ test_must_fail git archive --format=tar HEAD -- foo >/dev/null
+'
+
+test_done
diff --git a/t/t5004/empty.zip b/t/t5004/empty.zip
new file mode 100644
index 0000000000000000000000000000000000000000..1a76bb600558dc94913a80076fe8dbdef13c1b15
GIT binary patch
literal 62
zcmWIWW@TeQ0~!oz$rh;wDW;amhRMmM$%ZCLW|oGQX-P%~24+b{=4q+M#^$N!DF&$k
D8w?B~
literal 0
HcmV?d00001
--
1.8.2.rc3.4.gc6ed371
Jeff King