Support subqueries (#59)

Support `CALL {}` subquery syntax.
Also remove support for `USING PERIODIC COMMIT`, which doesn't exist anymore (it is replaced by `CALL {} IN TRANSACTIONS`)

Author: albertoventurini

language/cypher/src/main/java/com/albertoventurini/graphdbplugin/language/cypher/lexer/Cypher.bnf

@@ -85,7 +85,8 @@ private statement_recover::= !(';'
                         | K_EXPLAIN
                         | K_CALL
                         | K_OPTIONAL
-                        | K_DETACH)
+                        | K_DETACH
+                        | "}")
 
 /*************************
  * Statement
@@ -177,7 +178,7 @@ DropIndex ::= K_DROP K_INDEX IndexName K_IF_EXISTS?
 /*************************
  * Query
  */
-Query ::= StandaloneCall | BulkImportQuery | RegularQuery
+Query ::= StandaloneCall | RegularQuery
 
 //-- RegularQuery
 RegularQuery ::= SingleQuery Union*
@@ -201,13 +202,9 @@ ReadingClause ::= LoadCSV
               | Start
               | Match
               | Unwind
+              | CallSubQuery
               | InQueryCall
 
-//-- BulkImportQuery
-BulkImportQuery ::= PeriodicCommitHint LoadCSVQuery
-PeriodicCommitHint ::= K_USING K_PERIODIC K_COMMIT IntegerLiteral?
-LoadCSVQuery ::= LoadCSV SingleQuery?
-
 /*************************
  * Clauses
  */
@@ -260,7 +257,10 @@ SortItem ::= Expression (K_DESCENDING | K_DESC | K_ASCENDING | K_ASC)?
 Skip ::= K_SKIP Expression
 Limit ::= K_LIMIT Expression
 
-//-- Call
+//-- Call subquery
+CallSubQuery ::= K_CALL "{" Query "}" (K_IN_TRANSACTIONS (K_OF IntegerLiteral K_ROWS)?)? {pin=2}
+
+//-- Call procedure
 Call ::= K_CALL ProcedureInvocation ProcedureResults?
 InQueryCall ::= Call Where?
 StandaloneCall ::= Call (Where? Return)?
@@ -571,7 +571,6 @@ ReservedWord ::= K_MATCH
                 | K_REL
                 | K_REDUCE
                 | K_PROFILE
-                | K_PERIODIC
                 | K_ORDER
                 | K_OR
                 | K_OPTIONAL

language/cypher/src/main/java/com/albertoventurini/graphdbplugin/language/cypher/lexer/CypherLexer.flex

@@ -75,7 +75,6 @@ K_ASCENDING=[Aa][Ss][Cc][Ee][Nn][Dd][Ii][Nn][Gg]
 K_ASC=[Aa][Ss][Cc]
 K_SKIP=[Ss][Kk][Ii][Pp]
 K_LIMIT=[Ll][Ii][Mm][Ii][Tt]
-K_PERIODIC=[Pp][Ee][Rr][Ii][Oo][Dd][Ii][Cc]
 K_BEGIN=[Bb][Ee][Gg][Ii][Nn]
 K_COMMIT=[Cc][Oo][Mm][Mm][Ii][Tt]
 K_XOR=[Xx][Oo][Rr]
@@ -113,6 +112,7 @@ K_SCALAR=[Ss][Cc][Aa][Ll][Aa][Rr]
 K_OF=[Oo][Ff]
 K_ADD=[Aa][Dd][Dd]
 K_OPTIONS=[Oo][Pp][Tt][Ii][Oo][Nn][Ss]
+K_ROWS=[Rr][Oo][Ww][Ss]
 
 _EACH=[Ee][Aa][Cc][Hh]
 _IF=[Ii][Ff]
@@ -122,6 +122,8 @@ _TEXT=[Tt][Ee][Xx][Tt]
 _POINT=[Pp][Oo][Ii][Nn][Tt]
 _LABELS=[Ll][Aa][Bb][Ee][Ll][Ss]
 _TYPE=[Tt][Yy][Pp][Ee]
+_IN=[Ii][Nn]
+_TRANSACTIONS=[Tt][Rr][Aa][Nn][Ss][Aa][Cc][Tt][Ii][Oo][Nn][Ss]
 
 K_CREATE_INDEX={K_CREATE}{WHITE_SPACE}{K_INDEX}
 K_CREATE_RANGE_INDEX={K_CREATE}{WHITE_SPACE}{_RANGE}{WHITE_SPACE}{K_INDEX}
@@ -133,6 +135,7 @@ K_IF_NOT_EXISTS={_IF}{WHITE_SPACE}{K_NOT}{WHITE_SPACE}{K_EXISTS}
 K_ON_EACH_LABELS={K_ON}{WHITE_SPACE}{_EACH}{WHITE_SPACE}{_LABELS}
 K_ON_EACH_TYPE={K_ON}{WHITE_SPACE}{_EACH}{WHITE_SPACE}{_TYPE}
 K_ON_TYPE={K_ON}{WHITE_SPACE}{_TYPE}
+K_IN_TRANSACTIONS={_IN}{WHITE_SPACE}{_TRANSACTIONS}
 
 L_IDENTIFIER=[a-zA-Z_][a-zA-Z_$0-9]*
 L_IDENTIFIER_TEXT=\`[^`]+\`
@@ -229,7 +232,6 @@ BLOCK_COMMENT = "/*" ( ([^"*"]|[\r\n])* ("*"+ [^"*""/"] )? )* ("*" | "*"+"/")?
   {K_ASC}                   { return K_ASC; }
   {K_SKIP}                  { return K_SKIP; }
   {K_LIMIT}                 { return K_LIMIT; }
-  {K_PERIODIC}              { return K_PERIODIC; }
   {K_BEGIN}                 { return K_BEGIN; }
   {K_COMMIT}                { return K_COMMIT; }
   {K_XOR}                   { return K_XOR; }
@@ -268,6 +270,7 @@ BLOCK_COMMENT = "/*" ( ([^"*"]|[\r\n])* ("*"+ [^"*""/"] )? )* ("*" | "*"+"/")?
   {K_ADD}                   { return K_ADD; }
 
   {K_OPTIONS}               { return K_OPTIONS; }
+  {K_ROWS}                  { return K_ROWS; }
 
   {K_CREATE_INDEX}          { return K_CREATE_INDEX; }
   {K_CREATE_RANGE_INDEX}    { return K_CREATE_RANGE_INDEX; }
@@ -279,6 +282,7 @@ BLOCK_COMMENT = "/*" ( ([^"*"]|[\r\n])* ("*"+ [^"*""/"] )? )* ("*" | "*"+"/")?
   {K_ON_EACH_LABELS}        { return K_ON_EACH_LABELS; }
   {K_ON_EACH_TYPE}          { return K_ON_EACH_TYPE; }
   {K_ON_TYPE}               { return K_ON_TYPE; }
+  {K_IN_TRANSACTIONS}       { return K_IN_TRANSACTIONS; }
 
   {L_IDENTIFIER}            { return L_IDENTIFIER; }
   {L_IDENTIFIER_TEXT}       { return L_IDENTIFIER_TEXT; }

testing/integration-neo4j/src/test/java/com/albertoventurini/graphdbplugin/test/integration/neo4j/tests/cypher/parsing/QueryParsingTest.java

@@ -17,8 +17,4 @@ public QueryParsingTest() {
     public void testMultipleQueries() {
         doTest(true);
     }
-
-    public void testBulkImport() {
-        doTest(true);
-    }
 }

testing/integration-neo4j/src/test/java/com/albertoventurini/graphdbplugin/test/integration/neo4j/tests/cypher/parsing/clause/QueryClauseParsingTest.java

@@ -58,6 +58,14 @@ public void testStart() {
         doTest(true);
     }
 
+    public void testSubQueries() {
+        doTest(true);
+    }
+
+    public void testSubQueriesInTransactions() {
+        doTest(true);
+    }
+
     public void testUnion() {
         doTest(true);
     }

testing/integration-neo4j/src/test/resources/parsing/query/BulkImport.cyp

@@ -0,0 +1,11 @@
+CALL {
+  RETURN "Hello" AS msg
+}
+RETURN msg;
+CALL {
+  WITH xs
+  UNWIND xs AS x
+  MATCH (n:Node {name: x})
+  RETURN n.name AS name
+}
+RETURN name;