+test_begin_subtest 'Adding flags to duplicate message tags the mail'
+add_message [subject]='"Duplicated message"' [dir]=cur [filename]='duplicated-message:2,'
+cp "$MAIL_DIR/cur/duplicated-message:2," "$MAIL_DIR/cur/duplicated-message-copy:2,RS"
+NOTMUCH_NEW > output
+notmuch search subject:"Duplicated message" | notmuch_search_sanitize >> output
+test_expect_equal "$(< output)" "No new mail.
+thread:XXX 2001-01-05 [1/1] Notmuch Test Suite; Duplicated message (inbox replied)"
+
+test_begin_subtest "Adding duplicate message without flags does not remove tags"
+cp "$MAIL_DIR/cur/duplicated-message-copy:2,RS" "$MAIL_DIR/cur/duplicated-message-another-copy:2,"
+NOTMUCH_NEW > output
+notmuch search subject:"Duplicated message" | notmuch_search_sanitize >> output
+test_expect_equal "$(< output)" "No new mail.
+thread:XXX 2001-01-05 [1/1] Notmuch Test Suite; Duplicated message (inbox replied)"
+
+test_begin_subtest "Tag changes modify flags of multiple files"
+notmuch tag -replied subject:"Duplicated message"
+(cd $MAIL_DIR/cur/; ls duplicated*) > actual
+test_expect_equal "$(< actual)" "duplicated-message-another-copy:2,S
+duplicated-message-copy:2,S
+duplicated-message:2,S"
+
+test_begin_subtest "Synchronizing tag changes preserves unsupported maildir flags"
+add_message [subject]='"Unsupported maildir flags"' [dir]=cur [filename]='unsupported-maildir-flags:2,FSZxyz'
+notmuch tag +unread +draft -flagged subject:"Unsupported maildir flags"
+test_expect_equal "$(cd $MAIL_DIR/cur/; ls unsupported*)" "unsupported-maildir-flags:2,DZxyz"
+
+test_begin_subtest "A file with non-compliant maildir info will not be renamed"
+add_message [subject]='"Non-compliant maildir info"' [dir]=cur [filename]='non-compliant-maildir-info:2,These-are-not-flags-in-ASCII-order-donottouch'
+notmuch tag +unread +draft -flagged subject:"Non-compliant maildir info"
+test_expect_equal "$(cd $MAIL_DIR/cur/; ls non-compliant*)" "non-compliant-maildir-info:2,These-are-not-flags-in-ASCII-order-donottouch"
+
+test_begin_subtest "Files in new/ get default synchronized tags"
+OLDCONFIG=$(notmuch config get new.tags)
+notmuch config set new.tags test
+add_message [subject]='"File in new/"' [dir]=new [filename]='file-in-new'
+notmuch config set new.tags $OLDCONFIG
+notmuch search 'subject:"File in new"' | notmuch_search_sanitize > output
+test_expect_equal "$(< output)" \
+"thread:XXX 2001-01-05 [1/1] Notmuch Test Suite; File in new/ (test unread)"
+