From 216d8509e7cfaf96d560db0d505a642c8b7641e3 Mon Sep 17 00:00:00 2001
From: Garfield Lee Freeman <gfreeman@paloaltonetworks.com>
Date: Mon, 8 Apr 2024 13:57:58 +0200
Subject: [PATCH] just return nil filtering group if parse string is nil

---
 filtering/parse.go      |  2 +-
 filtering/parse_test.go | 10 +++++++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/filtering/parse.go b/filtering/parse.go
index bcdd6c74..45b5ce37 100644
--- a/filtering/parse.go
+++ b/filtering/parse.go
@@ -14,7 +14,7 @@ func Parse(s string, quote string) (*Group, error) {
 	} else if quote == "&" || quote == "|" || quote == "(" || quote == ")" || quote == " " || quote == `\` || quote == "!" || quote == "." || quote == "<" || quote == ">" || quote == "=" || quote == "-" || quote == "_" {
 		return nil, fmt.Errorf("quote character cannot be a reserved character")
 	} else if s == "" {
-		return nil, fmt.Errorf("logic string is empty")
+		return nil, nil
 	}
 
 	var ch rune
diff --git a/filtering/parse_test.go b/filtering/parse_test.go
index 0e388648..411b5db2 100644
--- a/filtering/parse_test.go
+++ b/filtering/parse_test.go
@@ -932,7 +932,6 @@ func TestParseReturnsError(t *testing.T) {
 		"foobar",
 		"(",
 		")",
-		"",
 	}
 
 	for _, s := range checks {
@@ -966,3 +965,12 @@ func TestParseWithInvalidQuoteReturnsError(t *testing.T) {
 		}
 	}
 }
+
+func TestParseEmptyString(t *testing.T) {
+	resp, err := Parse("", `"`)
+	if err != nil {
+		t.Fatalf("parse empty string error: %s", err)
+	} else if resp != nil {
+		t.Fatalf("parse empty string has non-nil group")
+	}
+}