diff --git a/t/t3900-i18n-commit.sh b/t/t3900-i18n-commit.sh
index 46fd47cb0f..6714b0dd6e 100755
--- a/t/t3900-i18n-commit.sh
+++ b/t/t3900-i18n-commit.sh
@@ -8,7 +8,7 @@ test_description='commit and log output encodings'
 . ./test-lib.sh
 
 compare_with () {
-	git-show -s "$1" | sed -e '1,/^$/d' -e 's/^    //' -e '$d' >current &&
+	git-show -s $1 | sed -e '1,/^$/d' -e 's/^    //' -e '$d' >current &&
 	diff -u current "$2"
 }
 
@@ -112,4 +112,11 @@ do
 	done
 done
 
+for H in ISO-8859-1 EUCJP ISO-2022-JP
+do
+	test_expect_success "No conversion with $H" '
+		compare_with "--encoding=none '$H'" ../t3900/'$H'.txt
+	'
+done
+
 test_done