fetch-pack: make packfile URIs work with transfer.fsckobjects

When fetching with packfile URIs and transfer.fsckobjects=1, use the
--fsck-objects instead of the --strict flag when invoking index-pack so
that links are not checked, only objects. This is because incomplete
links are expected. (A subsequent connectivity check will be done when
all the packs have been downloaded regardless of whether
transfer.fsckobjects is set.)

This is similar to 98a2ea46c2 ("fetch-pack: do not check links for
partial fetch", 2018-03-15), but for packfile URIs instead of partial
clones.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fetch-pack.c

@@ -896,7 +896,7 @@ static int get_pack(struct fetch_pack_args *args,
 	    : transfer_fsck_objects >= 0
 	    ? transfer_fsck_objects
 	    : 0) {
-		if (args->from_promisor)
+		if (args->from_promisor || !only_packfile)
 			/*
 			 * We cannot use --strict in index-pack because it
 			 * checks both broken objects and links, but we only

t/t5702-protocol-v2.sh

@@ -883,6 +883,59 @@ test_expect_success 'fetching with valid packfile URI but invalid hash fails' '
 	test_i18ngrep "pack downloaded from.*does not match expected hash" err
 '
 
+test_expect_success 'packfile-uri with transfer.fsckobjects' '
+	P="$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+	rm -rf "$P" http_child log &&
+
+	git init "$P" &&
+	git -C "$P" config "uploadpack.allowsidebandall" "true" &&
+
+	echo my-blob >"$P/my-blob" &&
+	git -C "$P" add my-blob &&
+	git -C "$P" commit -m x &&
+
+	configure_exclusion "$P" my-blob >h &&
+
+	sane_unset GIT_TEST_SIDEBAND_ALL &&
+	git -c protocol.version=2 -c transfer.fsckobjects=1 \
+		-c fetch.uriprotocols=http,https \
+		clone "$HTTPD_URL/smart/http_parent" http_child &&
+
+	# Ensure that there are exactly 4 files (2 .pack and 2 .idx).
+	ls http_child/.git/objects/pack/* >filelist &&
+	test_line_count = 4 filelist
+'
+
+test_expect_success 'packfile-uri with transfer.fsckobjects fails on bad object' '
+	P="$HTTPD_DOCUMENT_ROOT_PATH/http_parent" &&
+	rm -rf "$P" http_child log &&
+
+	git init "$P" &&
+	git -C "$P" config "uploadpack.allowsidebandall" "true" &&
+
+	cat >bogus-commit <<-EOF &&
+	tree $EMPTY_TREE
+	author Bugs Bunny 1234567890 +0000
+	committer Bugs Bunny <bugs@bun.ni> 1234567890 +0000
+
+	This commit object intentionally broken
+	EOF
+	BOGUS=$(git -C "$P" hash-object -t commit -w --stdin <bogus-commit) &&
+	git -C "$P" branch bogus-branch "$BOGUS" &&
+
+	echo my-blob >"$P/my-blob" &&
+	git -C "$P" add my-blob &&
+	git -C "$P" commit -m x &&
+
+	configure_exclusion "$P" my-blob >h &&
+
+	sane_unset GIT_TEST_SIDEBAND_ALL &&
+	test_must_fail git -c protocol.version=2 -c transfer.fsckobjects=1 \
+		-c fetch.uriprotocols=http,https \
+		clone "$HTTPD_URL/smart/http_parent" http_child 2>error &&
+	test_i18ngrep "invalid author/committer line - missing email" error
+'
+
 # DO NOT add non-httpd-specific tests here, because the last part of this
 # test script is only executed when httpd is available and enabled.