do not override receive-pack errors

Receive runs rev-list --verify-objects in order to detect missing
objects. However, such errors are ignored and overridden later.
Instead, consequently ignore all update commands for which an error has
already been detected.

Some tests in t5504 are obsoleted by this change, because invalid
objects are detected even if fsck is not enabled. Instead, they now test
for different error messages depending on whether or not fsck is turned
on. A better fix would be to force a corruption that will be detected by
fsck but not by rev-list.

Signed-off-by: Clemens Buchacher <drizzd@aon.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/receive-pack.c

@@ -623,8 +623,10 @@ static void check_aliased_updates(struct command *commands)
 	}
 	sort_string_list(&ref_list);
 
-	for (cmd = commands; cmd; cmd = cmd->next)
-		check_aliased_update(cmd, &ref_list);
+	for (cmd = commands; cmd; cmd = cmd->next) {
+		if (!cmd->error_string)
+			check_aliased_update(cmd, &ref_list);
+	}
 
 	string_list_clear(&ref_list, 0);
 }
@@ -688,18 +690,26 @@ static void execute_commands(struct command *commands, const char *unpacker_erro
 		set_connectivity_errors(commands);
 
 	if (run_receive_hook(commands, pre_receive_hook, 0)) {
-		for (cmd = commands; cmd; cmd = cmd->next)
-			cmd->error_string = "pre-receive hook declined";
+		for (cmd = commands; cmd; cmd = cmd->next) {
+			if (!cmd->error_string)
+				cmd->error_string = "pre-receive hook declined";
+		}
 		return;
 	}
 
 	check_aliased_updates(commands);
 
 	head_name = resolve_ref("HEAD", sha1, 0, NULL);
 
-	for (cmd = commands; cmd; cmd = cmd->next)
-		if (!cmd->skip_update)
-			cmd->error_string = update(cmd);
+	for (cmd = commands; cmd; cmd = cmd->next) {
+		if (cmd->error_string)
+			continue;
+
+		if (cmd->skip_update)
+			continue;
+
+		cmd->error_string = update(cmd);
+	}
 }
 
 static struct command *read_head_info(void)

t/t5504-fetch-receive-strict.sh

@@ -58,6 +58,11 @@ test_expect_success 'fetch with transfer.fsckobjects' '
 	)
 '
 
+cat >exp <<EOF
+To dst
+!	refs/heads/master:refs/heads/test	[remote rejected] (missing necessary objects)
+EOF
+
 test_expect_success 'push without strict' '
 	rm -rf dst &&
 	git init dst &&
@@ -66,7 +71,8 @@ test_expect_success 'push without strict' '
 		git config fetch.fsckobjects false &&
 		git config transfer.fsckobjects false
 	) &&
-	git push dst master:refs/heads/test
+	test_must_fail git push --porcelain dst master:refs/heads/test >act &&
+	test_cmp exp act
 '
 
 test_expect_success 'push with !receive.fsckobjects' '
@@ -77,9 +83,15 @@ test_expect_success 'push with !receive.fsckobjects' '
 		git config receive.fsckobjects false &&
 		git config transfer.fsckobjects true
 	) &&
-	git push dst master:refs/heads/test
+	test_must_fail git push --porcelain dst master:refs/heads/test >act &&
+	test_cmp exp act
 '
 
+cat >exp <<EOF
+To dst
+!	refs/heads/master:refs/heads/test	[remote rejected] (n/a (unpacker error))
+EOF
+
 test_expect_success 'push with receive.fsckobjects' '
 	rm -rf dst &&
 	git init dst &&
@@ -88,7 +100,8 @@ test_expect_success 'push with receive.fsckobjects' '
 		git config receive.fsckobjects true &&
 		git config transfer.fsckobjects false
 	) &&
-	test_must_fail git push dst master:refs/heads/test
+	test_must_fail git push --porcelain dst master:refs/heads/test >act &&
+	test_cmp exp act
 '
 
 test_expect_success 'push with transfer.fsckobjects' '
@@ -98,7 +111,8 @@ test_expect_success 'push with transfer.fsckobjects' '
 		cd dst &&
 		git config transfer.fsckobjects true
 	) &&
-	test_must_fail git push dst master:refs/heads/test
+	test_must_fail git push --porcelain dst master:refs/heads/test >act &&
+	test_cmp exp act
 '
 
 test_done