@@ -861,4 +861,59 @@ test_expect_success CASE_INSENSITIVE_FS 'case insensitive+preserving' '
egrep "^event: abc/def/xyz$" ./insensitive.trace
'
+# The variable "unicode_debug" is defined in the following library
+# script to dump information about how the (OS, FS) handles Unicode
+# composition. Uncomment the following line if you want to enable it.
+#
+# unicode_debug=true
+
+. "$TEST_DIRECTORY/lib-unicode-nfc-nfd.sh"
+
+# See if the OS or filesystem does NFC/NFD aliasing/munging.
+#
+# The daemon should err on the side of caution and send BOTH the
+# NFC and NFD forms. It does not know the original spelling of
+# the pathname (how the user thinks it should be spelled), so
+# emit both and let the client decide (when necessary). This is
+# similar to "core.precomposeUnicode".
+#
+test_expect_success !UNICODE_COMPOSITION_SENSITIVE 'Unicode nfc/nfd' '
+ test_when_finished "stop_daemon_delete_repo test_unicode" &&
+
+ git init test_unicode &&
+
+ start_daemon -C test_unicode --tf "$PWD/unicode.trace" &&
+
+ # Create a directory using an NFC spelling.
+ #
+ mkdir test_unicode/nfc &&
+ mkdir test_unicode/nfc/c_${utf8_nfc} &&
+
+ # Create a directory using an NFD spelling.
+ #
+ mkdir test_unicode/nfd &&
+ mkdir test_unicode/nfd/d_${utf8_nfd} &&
+
+ git -C test_unicode fsmonitor--daemon stop &&
+
+ if test_have_prereq UNICODE_NFC_PRESERVED
+ then
+ # We should have seen NFC event from OS.
+ # We should not have synthesized an NFD event.
+ egrep "^event: nfc/c_${utf8_nfc}/?$" ./unicode.trace &&
+ egrep -v "^event: nfc/c_${utf8_nfd}/?$" ./unicode.trace
+ else
+ # We should have seen NFD event from OS.
+ # We should have synthesized an NFC event.
+ egrep "^event: nfc/c_${utf8_nfd}/?$" ./unicode.trace &&
+ egrep "^event: nfc/c_${utf8_nfc}/?$" ./unicode.trace
+ fi &&
+
+ # We assume UNICODE_NFD_PRESERVED.
+ # We should have seen explicit NFD from OS.
+ # We should have synthesized an NFC event.
+ egrep "^event: nfd/d_${utf8_nfd}/?$" ./unicode.trace &&
+ egrep "^event: nfd/d_${utf8_nfc}/?$" ./unicode.trace
+'
+
test_done