patch, 8 partsGIT_TEST_PROTOCOL_VERSION, this time on master

protocol.c, t/README, t/t5400-send-pack.sh, t/t5551-http-fetch-smart.sh

diff --git a/protocol.c b/protocol.c
index 5e636785d1..9741f05750 100644
--- a/protocol.c
+++ b/protocol.c
@@ -17,6 +17,10 @@ static enum protocol_version parse_protocol_version(const char *value)
 enum protocol_version get_protocol_version_config(void)
 {
 	const char *value;
+	enum protocol_version retval = protocol_v0;
+	const char *git_test_k = "GIT_TEST_PROTOCOL_VERSION";
+	const char *git_test_v = getenv(git_test_k);
+
 	if (!git_config_get_string_const("protocol.version", &value)) {
 		enum protocol_version version = parse_protocol_version(value);
 
@@ -24,10 +28,19 @@ enum protocol_version get_protocol_version_config(void)
 			die("unknown value for config 'protocol.version': %s",
 			    value);
 
-		return version;
+		retval = version;
+	}
+
+	if (git_test_v && *git_test_v) {
+		enum protocol_version env = parse_protocol_version(git_test_v);
+
+		if (env == protocol_unknown_version)
+			die("unknown value for %s: %s", git_test_k, git_test_v);
+		if (retval < env)
+			retval = env;
 	}
 
-	return protocol_v0;
+	return retval;
 }
 
 enum protocol_version determine_protocol_version_server(void)
diff --git a/t/README b/t/README
index 886bbec5bc..3125bfa6b6 100644
--- a/t/README
+++ b/t/README
@@ -341,6 +341,9 @@ marked strings" in po/README for details.
 GIT_TEST_SPLIT_INDEX=<boolean> forces split-index mode on the whole
 test suite. Accept any boolean values that are accepted by git-config.
 
+GIT_TEST_PROTOCOL_VERSION=<n>, when set, overrides the
+'protocol.version' setting to n if it is less than n.
+
 GIT_TEST_FULL_IN_PACK_ARRAY=<boolean> exercises the uncommon
 pack-objects code path where there are more than 1024 packs even if
 the actual number of packs in repository is below this limit. Accept
diff --git a/t/t5400-send-pack.sh b/t/t5400-send-pack.sh
index f1932ea431..571d620aed 100755
--- a/t/t5400-send-pack.sh
+++ b/t/t5400-send-pack.sh
@@ -288,7 +288,7 @@ test_expect_success 'receive-pack de-dupes .have lines' '
 	$shared .have
 	EOF
 
-	GIT_TRACE_PACKET=$(pwd)/trace \
+	GIT_TRACE_PACKET=$(pwd)/trace GIT_TEST_PROTOCOL_VERSION= \
 	    git push \
 		--receive-pack="unset GIT_TRACE_PACKET; git-receive-pack" \
 		fork HEAD:foo &&
diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh
index ba83e567e5..a852684e16 100755
--- a/t/t5551-http-fetch-smart.sh
+++ b/t/t5551-http-fetch-smart.sh
@@ -43,7 +43,8 @@ test_expect_success 'clone http repository' '
 	< Cache-Control: no-cache, max-age=0, must-revalidate
 	< Content-Type: application/x-git-upload-pack-result
 	EOF
-	GIT_TRACE_CURL=true git clone --quiet $HTTPD_URL/smart/repo.git clone 2>err &&
+	GIT_TRACE_CURL=true GIT_TEST_PROTOCOL_VERSION= \
+		git clone --quiet $HTTPD_URL/smart/repo.git clone 2>err &&
 	test_cmp file clone/file &&
 	tr '\''\015'\'' Q <err |
 	sed -e "

diff --git a/t/t5601-clone.sh b/t/t5601-clone.sh
index d6948cbdab..a454b143ea 100755
--- a/t/t5601-clone.sh
+++ b/t/t5601-clone.sh
@@ -345,7 +345,7 @@ expect_ssh () {
 }
 
 test_expect_success 'clone myhost:src uses ssh' '
-	git clone myhost:src ssh-clone &&
+	GIT_TEST_PROTOCOL_VERSION=0 git clone myhost:src ssh-clone &&
 	expect_ssh myhost src
 '
 
@@ -356,12 +356,12 @@ test_expect_success !MINGW,!CYGWIN 'clone local path foo:bar' '
 '
 
 test_expect_success 'bracketed hostnames are still ssh' '
-	git clone "[myhost:123]:src" ssh-bracket-clone &&
+	GIT_TEST_PROTOCOL_VERSION=0 git clone "[myhost:123]:src" ssh-bracket-clone &&
 	expect_ssh "-p 123" myhost src
 '
 
 test_expect_success 'OpenSSH variant passes -4' '
-	git clone -4 "[myhost:123]:src" ssh-ipv4-clone &&
+	GIT_TEST_PROTOCOL_VERSION=0 git clone -4 "[myhost:123]:src" ssh-ipv4-clone &&
 	expect_ssh "-4 -p 123" myhost src
 '
 
@@ -405,7 +405,7 @@ test_expect_success 'OpenSSH-like uplink is treated as ssh' '
 	test_when_finished "rm -f \"\$TRASH_DIRECTORY/uplink\"" &&
 	GIT_SSH="$TRASH_DIRECTORY/uplink" &&
 	test_when_finished "GIT_SSH=\"\$TRASH_DIRECTORY/ssh\$X\"" &&
-	git clone "[myhost:123]:src" ssh-bracket-clone-sshlike-uplink &&
+	GIT_TEST_PROTOCOL_VERSION=0 git clone "[myhost:123]:src" ssh-bracket-clone-sshlike-uplink &&
 	expect_ssh "-p 123" myhost src
 '
 
@@ -444,14 +444,14 @@ test_expect_success 'single quoted plink.exe in GIT_SSH_COMMAND' '
 
 test_expect_success 'GIT_SSH_VARIANT overrides plink detection' '
 	copy_ssh_wrapper_as "$TRASH_DIRECTORY/plink" &&
-	GIT_SSH_VARIANT=ssh \
-	git clone "[myhost:123]:src" ssh-bracket-clone-variant-1 &&
+	GIT_TEST_PROTOCOL_VERSION=0 GIT_SSH_VARIANT=ssh \
+		git clone "[myhost:123]:src" ssh-bracket-clone-variant-1 &&
 	expect_ssh "-p 123" myhost src
 '
 
 test_expect_success 'ssh.variant overrides plink detection' '
 	copy_ssh_wrapper_as "$TRASH_DIRECTORY/plink" &&
-	git -c ssh.variant=ssh \
+	GIT_TEST_PROTOCOL_VERSION=0 git -c ssh.variant=ssh \
 		clone "[myhost:123]:src" ssh-bracket-clone-variant-2 &&
 	expect_ssh "-p 123" myhost src
 '
@@ -482,7 +482,7 @@ counter=0
 # $3 path
 test_clone_url () {
 	counter=$(($counter + 1))
-	test_might_fail git clone "$1" tmp$counter &&
+	test_might_fail env GIT_TEST_PROTOCOL_VERSION=0 git clone "$1" tmp$counter &&
 	shift &&
 	expect_ssh "$@"
 }

t/t5500-fetch-pack.sh, t/t5516-fetch-push.sh, t/t5551-http-fetch-smart.sh, t/t7406-submodule-update.sh

diff --git a/t/t5500-fetch-pack.sh b/t/t5500-fetch-pack.sh
index 49c540b1e1..0ef4d6f20c 100755
--- a/t/t5500-fetch-pack.sh
+++ b/t/t5500-fetch-pack.sh
@@ -636,7 +636,9 @@ test_expect_success 'fetch-pack cannot fetch a raw sha1 that is not advertised a
 	test_commit -C server 6 &&
 
 	git init client &&
-	test_must_fail git -C client fetch-pack ../server \
+	# Some protocol versions (e.g. 2) support fetching
+	# unadvertised objects, so restrict this test to v0.
+	test_must_fail env GIT_TEST_PROTOCOL_VERSION= git -C client fetch-pack ../server \
 		$(git -C server rev-parse refs/heads/master^) 2>err &&
 	test_i18ngrep "Server does not allow request for unadvertised object" err
 '
diff --git a/t/t5516-fetch-push.sh b/t/t5516-fetch-push.sh
index 37e8e80893..4bfbb79654 100755
--- a/t/t5516-fetch-push.sh
+++ b/t/t5516-fetch-push.sh
@@ -1147,8 +1147,12 @@ test_expect_success 'fetch exact SHA1' '
 		git prune &&
 		test_must_fail git cat-file -t $the_commit &&
 
+		# Some protocol versions (e.g. 2) support fetching
+		# unadvertised objects, so restrict this test to v0.
+
 		# fetching the hidden object should fail by default
-		test_must_fail git fetch -v ../testrepo $the_commit:refs/heads/copy 2>err &&
+		test_must_fail env GIT_TEST_PROTOCOL_VERSION= \
+			git fetch -v ../testrepo $the_commit:refs/heads/copy 2>err &&
 		test_i18ngrep "Server does not allow request for unadvertised object" err &&
 		test_must_fail git rev-parse --verify refs/heads/copy &&
 
@@ -1204,7 +1208,10 @@ do
 		mk_empty shallow &&
 		(
 			cd shallow &&
-			test_must_fail git fetch --depth=1 ../testrepo/.git $SHA1 &&
+			# Some protocol versions (e.g. 2) support fetching
+			# unadvertised objects, so restrict this test to v0.
+			test_must_fail env GIT_TEST_PROTOCOL_VERSION= \
+				git fetch --depth=1 ../testrepo/.git $SHA1 &&
 			git --git-dir=../testrepo/.git config uploadpack.allowreachablesha1inwant true &&
 			git fetch --depth=1 ../testrepo/.git $SHA1 &&
 			git cat-file commit $SHA1
@@ -1232,15 +1239,20 @@ do
 		mk_empty shallow &&
 		(
 			cd shallow &&
-			test_must_fail ok=sigpipe git fetch ../testrepo/.git $SHA1_3 &&
-			test_must_fail ok=sigpipe git fetch ../testrepo/.git $SHA1_1 &&
+			# Some protocol versions (e.g. 2) support fetching
+			# unadvertised objects, so restrict this test to v0.
+			test_must_fail ok=sigpipe env GIT_TEST_PROTOCOL_VERSION= \
+				git fetch ../testrepo/.git $SHA1_3 &&
+			test_must_fail ok=sigpipe env GIT_TEST_PROTOCOL_VERSION= \
+				git fetch ../testrepo/.git $SHA1_1 &&
 			git --git-dir=../testrepo/.git config uploadpack.allowreachablesha1inwant true &&
 			git fetch ../testrepo/.git $SHA1_1 &&
 			git cat-file commit $SHA1_1 &&
 			test_must_fail git cat-file commit $SHA1_2 &&
 			git fetch ../testrepo/.git $SHA1_2 &&
 			git cat-file commit $SHA1_2 &&
-			test_must_fail ok=sigpipe git fetch ../testrepo/.git $SHA1_3
+			test_must_fail ok=sigpipe env GIT_TEST_PROTOCOL_VERSION= \
+				git fetch ../testrepo/.git $SHA1_3
 		)
 	'
 done
diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh
index a852684e16..f02ae3b797 100755
--- a/t/t5551-http-fetch-smart.sh
+++ b/t/t5551-http-fetch-smart.sh
@@ -307,7 +307,10 @@ test_expect_success 'test allowreachablesha1inwant with unreachable' '
 
 	git init --bare test_reachable.git &&
 	git -C test_reachable.git remote add origin "$HTTPD_URL/smart/repo.git" &&
-	test_must_fail git -C test_reachable.git fetch origin "$(git rev-parse HEAD)"
+	# Some protocol versions (e.g. 2) support fetching
+	# unadvertised objects, so restrict this test to v0.
+	test_must_fail env GIT_TEST_PROTOCOL_VERSION= \
+		git -C test_reachable.git fetch origin "$(git rev-parse HEAD)"
 '
 
 test_expect_success 'test allowanysha1inwant with unreachable' '
@@ -326,7 +329,10 @@ test_expect_success 'test allowanysha1inwant with unreachable' '
 
 	git init --bare test_reachable.git &&
 	git -C test_reachable.git remote add origin "$HTTPD_URL/smart/repo.git" &&
-	test_must_fail git -C test_reachable.git fetch origin "$(git rev-parse HEAD)" &&
+	# Some protocol versions (e.g. 2) support fetching
+	# unadvertised objects, so restrict this test to v0.
+	test_must_fail env GIT_TEST_PROTOCOL_VERSION= \
+		git -C test_reachable.git fetch origin "$(git rev-parse HEAD)" &&
 
 	git -C "$server" config uploadpack.allowanysha1inwant 1 &&
 	git -C test_reachable.git fetch origin "$(git rev-parse HEAD)"
diff --git a/t/t7406-submodule-update.sh b/t/t7406-submodule-update.sh
index e87164aa8f..c973278300 100755
--- a/t/t7406-submodule-update.sh
+++ b/t/t7406-submodule-update.sh
@@ -943,7 +943,10 @@ test_expect_success 'submodule update clone shallow submodule outside of depth'
 		cd super3 &&
 		sed -e "s#url = ../#url = file://$pwd/#" <.gitmodules >.gitmodules.tmp &&
 		mv -f .gitmodules.tmp .gitmodules &&
-		test_must_fail git submodule update --init --depth=1 2>actual &&
+		# Some protocol versions (e.g. 2) support fetching
+		# unadvertised objects, so restrict this test to v0.
+		test_must_fail env GIT_TEST_PROTOCOL_VERSION= \
+			git submodule update --init --depth=1 2>actual &&
 		test_i18ngrep "Direct fetching of that commit failed." actual &&
 		git -C ../submodule config uploadpack.allowReachableSHA1InWant true &&
 		git submodule update --init --depth=1 >actual &&

diff --git a/t/t5512-ls-remote.sh b/t/t5512-ls-remote.sh
index ced15ae122..e3c4a48c85 100755
--- a/t/t5512-ls-remote.sh
+++ b/t/t5512-ls-remote.sh
@@ -223,7 +223,9 @@ test_expect_success 'ls-remote --symref' '
 	$(git rev-parse refs/tags/mark1.10)	refs/tags/mark1.10
 	$(git rev-parse refs/tags/mark1.2)	refs/tags/mark1.2
 	EOF
-	git ls-remote --symref >actual &&
+	# Protocol v2 supports sending symrefs for refs other than HEAD, so use
+	# protocol v0 here.
+	GIT_TEST_PROTOCOL_VERSION= git ls-remote --symref >actual &&
 	test_cmp expect actual
 '
 
@@ -232,7 +234,9 @@ test_expect_success 'ls-remote with filtered symref (refname)' '
 	ref: refs/heads/master	HEAD
 	1bd44cb9d13204b0fe1958db0082f5028a16eb3a	HEAD
 	EOF
-	git ls-remote --symref . HEAD >actual &&
+	# Protocol v2 supports sending symrefs for refs other than HEAD, so use
+	# protocol v0 here.
+	GIT_TEST_PROTOCOL_VERSION= git ls-remote --symref . HEAD >actual &&
 	test_cmp expect actual
 '
 
@@ -243,7 +247,9 @@ test_expect_failure 'ls-remote with filtered symref (--heads)' '
 	1bd44cb9d13204b0fe1958db0082f5028a16eb3a	refs/heads/foo
 	1bd44cb9d13204b0fe1958db0082f5028a16eb3a	refs/heads/master
 	EOF
-	git ls-remote --symref --heads . >actual &&
+	# Protocol v2 supports sending symrefs for refs other than HEAD, so use
+	# protocol v0 here.
+	GIT_TEST_PROTOCOL_VERSION= git ls-remote --symref --heads . >actual &&
 	test_cmp expect actual
 '
 
@@ -252,9 +258,11 @@ test_expect_success 'ls-remote --symref omits filtered-out matches' '
 	1bd44cb9d13204b0fe1958db0082f5028a16eb3a	refs/heads/foo
 	1bd44cb9d13204b0fe1958db0082f5028a16eb3a	refs/heads/master
 	EOF
-	git ls-remote --symref --heads . >actual &&
+	# Protocol v2 supports sending symrefs for refs other than HEAD, so use
+	# protocol v0 here.
+	GIT_TEST_PROTOCOL_VERSION= git ls-remote --symref --heads . >actual &&
 	test_cmp expect actual &&
-	git ls-remote --symref . "refs/heads/*" >actual &&
+	GIT_TEST_PROTOCOL_VERSION= git ls-remote --symref . "refs/heads/*" >actual &&
 	test_cmp expect actual
 '
 

diff --git a/t/t5700-protocol-v1.sh b/t/t5700-protocol-v1.sh
index ba86a44eb1..d5ed196bfd 100755
--- a/t/t5700-protocol-v1.sh
+++ b/t/t5700-protocol-v1.sh
@@ -4,6 +4,9 @@ test_description='test git wire-protocol transition'
 
 TEST_NO_CREATE_REPO=1
 
+# This is a protocol-specific test.
+GIT_TEST_PROTOCOL_VERSION=
+
 . ./test-lib.sh
 
 # Test protocol v1 with 'git://' transport

t/t5515-fetch-merge-logic.sh, t/t5539-fetch-http-shallow.sh, t/t5541-http-push-smart.sh, t/t5551-http-fetch-smart.sh

diff --git a/t/t5515-fetch-merge-logic.sh b/t/t5515-fetch-merge-logic.sh
index 36b0dbc01c..e55d8474ef 100755
--- a/t/t5515-fetch-merge-logic.sh
+++ b/t/t5515-fetch-merge-logic.sh
@@ -6,6 +6,10 @@
 
 test_description='Merge logic in fetch'
 
+# NEEDSWORK: If the overspecification of the expected result is reduced, we
+# might be able to run this test in all protocol versions.
+GIT_TEST_PROTOCOL_VERSION=
+
 . ./test-lib.sh
 
 LF='
diff --git a/t/t5539-fetch-http-shallow.sh b/t/t5539-fetch-http-shallow.sh
index 5fbf67c446..cdb687b93a 100755
--- a/t/t5539-fetch-http-shallow.sh
+++ b/t/t5539-fetch-http-shallow.sh
@@ -67,7 +67,10 @@ test_expect_success 'no shallow lines after receiving ACK ready' '
 		cd clone &&
 		git checkout --orphan newnew &&
 		test_commit new-too &&
-		GIT_TRACE_PACKET="$TRASH_DIRECTORY/trace" git fetch --depth=2 &&
+		# NEEDSWORK: If the overspecification of the expected result is reduced, we
+		# might be able to run this test in all protocol versions.
+		GIT_TRACE_PACKET="$TRASH_DIRECTORY/trace" GIT_TEST_PROTOCOL_VERSION= \
+			git fetch --depth=2 &&
 		grep "fetch-pack< ACK .* ready" ../trace &&
 		! grep "fetch-pack> done" ../trace
 	)
diff --git a/t/t5541-http-push-smart.sh b/t/t5541-http-push-smart.sh
index 5475afc052..0e3055ab98 100755
--- a/t/t5541-http-push-smart.sh
+++ b/t/t5541-http-push-smart.sh
@@ -47,7 +47,12 @@ test_expect_success 'no empty path components' '
 	cd "$ROOT_PATH" &&
 	git clone $HTTPD_URL/smart/test_repo.git/ test_repo_clone &&
 
-	check_access_log exp
+	# NEEDSWORK: If the overspecification of the expected result is reduced, we
+	# might be able to run this test in all protocol versions.
+	if test -z "$GIT_TEST_PROTOCOL_VERSION"
+	then
+		check_access_log exp
+	fi
 '
 
 test_expect_success 'clone remote repository' '
@@ -128,7 +133,12 @@ GET  /smart/test_repo.git/info/refs?service=git-receive-pack HTTP/1.1 200
 POST /smart/test_repo.git/git-receive-pack HTTP/1.1 200
 EOF
 test_expect_success 'used receive-pack service' '
-	check_access_log exp
+	# NEEDSWORK: If the overspecification of the expected result is reduced, we
+	# might be able to run this test in all protocol versions.
+	if test -z "$GIT_TEST_PROTOCOL_VERSION"
+	then
+		check_access_log exp
+	fi
 '
 
 test_http_push_nonff "$HTTPD_DOCUMENT_ROOT_PATH"/test_repo.git \
diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh
index f02ae3b797..a685d3edb6 100755
--- a/t/t5551-http-fetch-smart.sh
+++ b/t/t5551-http-fetch-smart.sh
@@ -81,12 +81,18 @@ test_expect_success 'clone http repository' '
 		/^< Content-Length: /d
 		/^< Transfer-Encoding: /d
 	" >actual &&
-	sed -e "s/^> Accept-Encoding: .*/> Accept-Encoding: ENCODINGS/" \
-			actual >actual.smudged &&
-	test_cmp exp actual.smudged &&
 
-	grep "Accept-Encoding:.*gzip" actual >actual.gzip &&
-	test_line_count = 2 actual.gzip
+	# NEEDSWORK: If the overspecification of the expected result is reduced, we
+	# might be able to run this test in all protocol versions.
+	if test -z "$GIT_TEST_PROTOCOL_VERSION"
+	then
+		sed -e "s/^> Accept-Encoding: .*/> Accept-Encoding: ENCODINGS/" \
+				actual >actual.smudged &&
+		test_cmp exp actual.smudged &&
+
+		grep "Accept-Encoding:.*gzip" actual >actual.gzip &&
+		test_line_count = 2 actual.gzip
+	fi
 '
 
 test_expect_success 'fetch changes via http' '
@@ -104,7 +110,13 @@ test_expect_success 'used upload-pack service' '
 	GET  /smart/repo.git/info/refs?service=git-upload-pack HTTP/1.1 200
 	POST /smart/repo.git/git-upload-pack HTTP/1.1 200
 	EOF
-	check_access_log exp
+
+	# NEEDSWORK: If the overspecification of the expected result is reduced, we
+	# might be able to run this test in all protocol versions.
+	if test -z "$GIT_TEST_PROTOCOL_VERSION"
+	then
+		check_access_log exp
+	fi
 '
 
 test_expect_success 'follow redirects (301)' '
@@ -216,8 +228,14 @@ test_expect_success 'cookies stored in http.cookiefile when http.savecookies set
 	git config http.cookiefile cookies.txt &&
 	git config http.savecookies true &&
 	git ls-remote $HTTPD_URL/smart_cookies/repo.git master &&
-	tail -3 cookies.txt | sort >cookies_tail.txt &&
-	test_cmp expect_cookies.txt cookies_tail.txt
+
+	# NEEDSWORK: If the overspecification of the expected result is reduced, we
+	# might be able to run this test in all protocol versions.
+	if test -z "$GIT_TEST_PROTOCOL_VERSION"
+	then
+		tail -3 cookies.txt | sort >cookies_tail.txt &&
+		test_cmp expect_cookies.txt cookies_tail.txt
+	fi
 '
 
 test_expect_success 'transfer.hiderefs works over smart-http' '

diff --git a/t/t5552-skipping-fetch-negotiator.sh b/t/t5552-skipping-fetch-negotiator.sh
index 30857b84a8..8a14be51a1 100755
--- a/t/t5552-skipping-fetch-negotiator.sh
+++ b/t/t5552-skipping-fetch-negotiator.sh
@@ -127,7 +127,10 @@ test_expect_success 'use ref advertisement to filter out commits' '
 	# not need to send any ancestors of "c3", but we still need to send "c3"
 	# itself.
 	test_config -C client fetch.negotiationalgorithm skipping &&
-	trace_fetch client origin to_fetch &&
+
+	# The ref advertisement itself is filtered when protocol v2 is used, so
+	# use v0.
+	GIT_TEST_PROTOCOL_VERSION= trace_fetch client origin to_fetch &&
 	have_sent c5 c4^ c2side &&
 	have_not_sent c4 c4^^ c4^^^
 '

diff --git a/t/t5503-tagfollow.sh b/t/t5503-tagfollow.sh
index 4ca48f0276..6041a4dd32 100755
--- a/t/t5503-tagfollow.sh
+++ b/t/t5503-tagfollow.sh
@@ -47,7 +47,7 @@ get_needs () {
 	test -s "$1" &&
 	perl -alne '
 		next unless $F[1] eq "upload-pack<";
-		last if $F[2] eq "0000";
+		next unless $F[2] eq "want";
 		print $F[2], " ", $F[3];
 	' "$1"
 }