From 56dcb86538afa27a0c379cbcab7dd02cd8277cf8 Mon Sep 17 00:00:00 2001
From: Akron <nils@diewald-online.de>
Date: Wed, 13 Sep 2023 07:43:32 +0200
Subject: [PATCH] Disallow empty regex in PQ+

Change-Id: Ifcda331007866616e6bd079e8d331dec9d1f880a
Reviewed-on: https://korap.ids-mannheim.de/gerrit/c/KorAP/Koral/+/7512
Reviewed-by: Nils Diewald <nils@diewald-online.de>
---
 Changes                                                       | 3 +++
 pom.xml                                                       | 2 +-
 src/main/antlr/poliqarpplus/Regex.g4                          | 2 +-
 .../korap/query/test/poliqarpplus/PQGrammarTest.java          | 4 ++--
 4 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/Changes b/Changes
index ecd5b3d5..3e98baaa 100644
--- a/Changes
+++ b/Changes
@@ -1,3 +1,6 @@
+0.41 2023-09-13
+    - [bugfix] Disallow empty regex in PQ+ (diewald)
+
 0.40 2023-07-26
     - [feature] Initial support for CQP
       (irimia, margaretha, diewald)
diff --git a/pom.xml b/pom.xml
index 8e38774a..6bdd5574 100644
--- a/pom.xml
+++ b/pom.xml
@@ -4,7 +4,7 @@
 
 	<groupId>de.ids_mannheim.korap</groupId>
 	<artifactId>Koral</artifactId>
-	<version>0.40.0</version>
+	<version>0.41.0</version>
 	<packaging>jar</packaging>
 	<name>Koral</name>
 	<url>https://korap.ids-mannheim.de</url>
diff --git a/src/main/antlr/poliqarpplus/Regex.g4 b/src/main/antlr/poliqarpplus/Regex.g4
index f83b3955..48c98082 100644
--- a/src/main/antlr/poliqarpplus/Regex.g4
+++ b/src/main/antlr/poliqarpplus/Regex.g4
@@ -15,4 +15,4 @@ fragment RE_chgroup  : '[' '^'? RE_char+ ']';
 fragment RE_quant    : ('.' | RE_char | RE_chgroup | ( '(' RE_expr ')')) ('?' | '*' | '+' | RE_focc) '?'?;
 fragment RE_group    : '(' RE_expr ')';
 fragment RE_expr     : ('.' | RE_char | RE_alter | RE_chgroup | RE_quant | RE_group | '^' )+;
-fragment RE_dquote   : ('"'|'„'|'“')  (RE_expr | '\'' | ':' )* ('"'|'“'|'”');
\ No newline at end of file
+fragment RE_dquote   : ('"'|'„'|'“')  (RE_expr | '\'' | ':' )+ ('"'|'“'|'”');
\ No newline at end of file
diff --git a/src/test/java/de/ids_mannheim/korap/query/test/poliqarpplus/PQGrammarTest.java b/src/test/java/de/ids_mannheim/korap/query/test/poliqarpplus/PQGrammarTest.java
index 536ae0c2..2b45c6a7 100644
--- a/src/test/java/de/ids_mannheim/korap/query/test/poliqarpplus/PQGrammarTest.java
+++ b/src/test/java/de/ids_mannheim/korap/query/test/poliqarpplus/PQGrammarTest.java
@@ -59,7 +59,7 @@ public void dquoutes () {
 
         // how it behaves
       assertEquals(
-        "(request (query (segment (token (key (regex \"\"))))) <EOF>)",
+        "(request query <EOF>)",  // see different behaviour of " and '; for ", the query is parsed and an empty regex is generated
         treeString("\"\"\"")
         );
        // how it should behave
@@ -68,7 +68,7 @@ public void dquoutes () {
     	 	 treeString("\"\"\"")
     	 	 );
         assertEquals(
-        "(request (query (sequence (segment (token (key (regex \"\")))) (segment (token (key -key))))) <EOF>)",  // see different behaviour of " and '; for ", the query is parsed and an empty regex is generated
+        "(request (query (segment (token (key -key)))) <EOF>)",  // see different behaviour of " and '; for ", the query is parsed and an empty regex is generated
         treeString("\"\"-key\"")
         );
         assertEquals(