test_cmp expect actual
'
+cat >nul_to_q_textconv <<'EOF'
+#!/bin/sh
+"$PERL_PATH" -pe 'y/\000/Q/' < "$1"
+EOF
+chmod +x nul_to_q_textconv
+
+test_expect_success 'setup textconv filters' '
+ echo a diff=foo >.gitattributes &&
+ git config diff.foo.textconv "\"$(pwd)\""/nul_to_q_textconv
+'
+
+test_expect_success 'grep does not honor textconv' '
+ test_must_fail git grep Qfile
+'
+
+test_expect_failure 'grep --textconv honors textconv' '
+ echo "a:binaryQfile" >expect &&
+ git grep --textconv Qfile >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success 'grep --no-textconv does not honor textconv' '
+ test_must_fail git grep --no-textconv Qfile
+'
+
+test_expect_failure 'grep --textconv blob honors textconv' '
+ echo "HEAD:a:binaryQfile" >expect &&
+ git grep --textconv Qfile HEAD:a >actual &&
+ test_cmp expect actual
+'
+
test_done