bug: Fix decode panic for invalid input

sqids · Sep 6, 2023 · d580058 · d580058
1 parent d65ffba
commit d580058
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Showing 2 changed files with 20 additions and 1 deletion.
diff --git a/sqids.go b/sqids.go
@@ -230,7 +230,11 @@ func (s *Sqids) Decode(id string) []uint64 {
 			}
 		}
 
-		rid = joinRuneSlices(chunks[1:], separator)
+		if len(chunks) > 0 {
+			rid = joinRuneSlices(chunks[1:], separator)
+		} else {
+			return []uint64{}
+		}
 	}
 
 	return ret

diff --git a/sqids_test.go b/sqids_test.go
@@ -42,3 +42,18 @@ func TestCalculateOffset(t *testing.T) {
 		}
 	}
 }
+
+func TestDecode(t *testing.T) {
+	s, err := New()
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if got, want := len(s.Decode("Re")), 0; got != want {
+		t.Fatalf(`len(s.Decode("Re")) = %d, want %d`, got, want)
+	}
+
+	if got, want := len(s.Decode("U9")), 1; got != want {
+		t.Fatalf(`len(s.Decode("U9")) = %d, want %d`, got, want)
+	}
+}