FIX: Queries like WITH (( ... AND ... ) AND ... ) used to fail.

Prior to this fix, query parse would throw an error when the query had a form similar to ... WITH ( (...) {AND,OR} ...). The reason were the nested pair of parenthesis in the first element of the disjunction or conjunction.

CHANGELOG.md

@@ -17,6 +17,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+* Bug in the query parser (MR!56) - The parser would throw an error when the
+  query contains a conjunction or disjunction filter with a first element which
+  is another disjunction or conjunction and being wrapped into parenthesis.
+
 ### Security
 
 ## [0.2] - 2020-09-02

src/main/java/org/caosdb/server/query/CQLParser.g4

@@ -312,7 +312,11 @@ conjunction returns [Conjunction c] locals [Conjunction dummy]
 		f1 = filter_expression {$c.add($f1.efi);}
 		|
 		LPAREN
-		f4 = filter_expression {$c.add($f4.efi);}
+		(
+			f4 = filter_expression {$c.add($f4.efi);}
+			| disjunction {$c.add($disjunction.d);}
+			| c3=conjunction {$c.addAll($c3.c);} 
+		)	
 		RPAREN
 	) 
 	( 
@@ -344,7 +348,11 @@ disjunction returns [Disjunction d]
 		f1 = filter_expression {$d.add($f1.efi);}
 		|
 		LPAREN
-		f4 = filter_expression {$d.add($f4.efi);}
+		(
+			f4 = filter_expression {$d.add($f4.efi);}
+			| conjunction {$d.add($conjunction.c);}
+			| d3 = disjunction {$d.addAll($d3.d);} 
+		)
 		RPAREN
 	)
 	(

src/test/java/org/caosdb/server/query/TestCQL.java

@@ -241,6 +241,7 @@ public class TestCQL {
   String referenceByLikePattern = "FIND ENTITY WHICH IS REFERENCED BY *name*";
 
   String emptyTextValue = "FIND ENTITY WITH prop=''";
+  String queryMR56 = "FIND ENTITY WITH ((p0 = v0 OR p1=v1) AND p2=v2)";
 
   @Test
   public void testQuery1()
@@ -6417,4 +6418,36 @@ public class TestCQL {
     final StoredAt storedAt = (StoredAt) sfq.filter;
     assertEquals("SAT(/data/in0.foo)", storedAt.toString());
   }
+
+  /**
+   * Testing a conjunction which begins with a nested disjunction. The bug was a parsing error which
+   * was caused by a missing option for a disjunction/conjunction, wrapped into parenthesis as first
+   * element of a conjunction/disjunction
+   *
+   * <p>String queryMR56 = "FIND ENTITY WITH ((p0 = v0 OR p1=v1) AND p2=v2)";
+   */
+  @Test
+  public void testMR56() {
+    CQLLexer lexer;
+    lexer = new CQLLexer(CharStreams.fromString(this.queryMR56));
+    final CommonTokenStream tokens = new CommonTokenStream(lexer);
+
+    final CQLParser parser = new CQLParser(tokens);
+    final CqContext sfq = parser.cq();
+
+    System.out.println(sfq.toStringTree(parser));
+
+    // 4 children: FIND, role, WHICHCLAUSE, EOF
+    assertEquals(4, sfq.getChildCount());
+    assertEquals("WITH((p0=v0ORp1=v1)ANDp2=v2)", sfq.getChild(2).getText());
+    assertEquals("ENTITY", sfq.r.toString());
+    assertEquals("Conjunction", sfq.filter.getClass().getSimpleName());
+    final ParseTree whichclause = sfq.getChild(2);
+    final ParseTree conjunction = whichclause.getChild(2);
+    assertEquals("(p0=v0ORp1=v1)ANDp2=v2", conjunction.getText());
+    final ParseTree disjunction = conjunction.getChild(1);
+    assertEquals("p0=v0ORp1=v1", disjunction.getText());
+    final ParseTree pov = conjunction.getChild(4);
+    assertEquals("p2=v2", pov.getText());
+  }
 }