Failure on regex escaping
diff --git a/src/test/java/de/ids_mannheim/korap/query/serialize/PoliqarpPlusQueryProcessorTest.java b/src/test/java/de/ids_mannheim/korap/query/serialize/PoliqarpPlusQueryProcessorTest.java
index 344e78c..171f1b3 100644
--- a/src/test/java/de/ids_mannheim/korap/query/serialize/PoliqarpPlusQueryProcessorTest.java
+++ b/src/test/java/de/ids_mannheim/korap/query/serialize/PoliqarpPlusQueryProcessorTest.java
@@ -154,6 +154,17 @@
         assertEquals("type:regex", res.at("/query/wrap/type").asText());
         assertEquals("orth", res.at("/query/wrap/layer").asText());
         assertEquals("match:eq", res.at("/query/wrap/match").asText());
+
+        // Escape regex symbols
+        query = "\"a\\.\"";
+        qs.setQuery(query, "poliqarpplus");
+        res = mapper.readTree(qs.toJSON());
+        assertEquals("koral:token", res.at("/query/@type").asText());
+        assertEquals("koral:term", res.at("/query/wrap/@type").asText());
+        assertEquals("a\\.", res.at("/query/wrap/key").asText());
+        assertEquals("type:regex", res.at("/query/wrap/type").asText());
+        assertEquals("orth", res.at("/query/wrap/layer").asText());
+        assertEquals("match:eq", res.at("/query/wrap/match").asText());
     }