Separate query types in openCypher grammars

Summary: depends on D1640

Reviewers: teon.banek, llugovic

Reviewed By: teon.banek

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D1643

src/query/frontend/ast/cypher_main_visitor.cpp

@@ -33,6 +33,40 @@ antlrcpp::Any CypherMainVisitor::visitExplainQuery(
   return query_;
 }
 
+antlrcpp::Any CypherMainVisitor::visitCypherQuery(
+    MemgraphCypher::CypherQueryContext *ctx) {
+  query_ = storage_.query();
+  DCHECK(ctx->singleQuery()) << "Expected single query.";
+  query_->single_query_ = ctx->singleQuery()->accept(this).as<SingleQuery *>();
+
+  // Check that union and union all dont mix
+  bool has_union = false;
+  bool has_union_all = false;
+  for (auto *child : ctx->cypherUnion()) {
+    if (child->ALL()) {
+      has_union_all = true;
+    } else {
+      has_union = true;
+    }
+    if (has_union && has_union_all) {
+      throw SemanticException("Invalid combination of UNION and UNION ALL.");
+    }
+    query_->cypher_unions_.push_back(child->accept(this).as<CypherUnion *>());
+  }
+
+  return query_;
+}
+
+antlrcpp::Any CypherMainVisitor::visitIndexQuery(
+    MemgraphCypher::IndexQueryContext *ctx) {
+  query_ = storage_.query();
+  DCHECK(ctx->createIndex()) << "Expected CREATE INDEX";
+  query_->single_query_ = storage_.Create<SingleQuery>();
+  query_->single_query_->clauses_.emplace_back(
+      ctx->createIndex()->accept(this).as<CreateIndex *>());
+  return query_;
+}
+
 antlrcpp::Any CypherMainVisitor::visitAuthQuery(
     MemgraphCypher::AuthQueryContext *ctx) {
   query_ = storage_.query();
@@ -67,30 +101,6 @@ antlrcpp::Any CypherMainVisitor::visitStreamQuery(
   return query_;
 }
 
-antlrcpp::Any CypherMainVisitor::visitRegularQuery(
-    MemgraphCypher::RegularQueryContext *ctx) {
-  query_ = storage_.query();
-  DCHECK(ctx->singleQuery()) << "Expected single query.";
-  query_->single_query_ = ctx->singleQuery()->accept(this).as<SingleQuery *>();
-
-  // Check that union and union all dont mix
-  bool has_union = false;
-  bool has_union_all = false;
-  for (auto *child : ctx->cypherUnion()) {
-    if (child->ALL()) {
-      has_union_all = true;
-    } else {
-      has_union = true;
-    }
-    if (has_union && has_union_all) {
-      throw SemanticException("Invalid combination of UNION and UNION ALL.");
-    }
-    query_->cypher_unions_.push_back(child->accept(this).as<CypherUnion *>());
-  }
-
-  return query_;
-}
-
 antlrcpp::Any CypherMainVisitor::visitCypherUnion(
     MemgraphCypher::CypherUnionContext *ctx) {
   bool distinct = !ctx->ALL();
@@ -227,10 +237,6 @@ antlrcpp::Any CypherMainVisitor::visitClause(
   if (ctx->unwind()) {
     return static_cast<Clause *>(ctx->unwind()->accept(this).as<Unwind *>());
   }
-  if (ctx->createIndex()) {
-    return static_cast<Clause *>(
-        ctx->createIndex()->accept(this).as<CreateIndex *>());
-  }
   // TODO: implement other clauses.
   throw utils::NotYetImplemented("clause '{}'", ctx->getText());
   return 0;

src/query/frontend/ast/cypher_main_visitor.hpp

@@ -134,6 +134,18 @@ class CypherMainVisitor : public antlropencypher::MemgraphCypherBaseVisitor {
     return expression;
   }
 
+  /**
+   * @return Query*
+   */
+  antlrcpp::Any visitCypherQuery(
+      MemgraphCypher::CypherQueryContext *ctx) override;
+
+  /**
+   * @return Query*
+   */
+  antlrcpp::Any visitIndexQuery(
+      MemgraphCypher::IndexQueryContext *ctx) override;
+
   /**
    * @return Query*
    */
@@ -151,12 +163,6 @@ class CypherMainVisitor : public antlropencypher::MemgraphCypherBaseVisitor {
   antlrcpp::Any visitStreamQuery(
       MemgraphCypher::StreamQueryContext *ctx) override;
 
-  /**
-   * @return Query*
-   */
-  antlrcpp::Any visitRegularQuery(
-      MemgraphCypher::RegularQueryContext *ctx) override;
-
   /**
    * @return CypherUnion*
    */

src/query/frontend/opencypher/grammar/Cypher.g4

@@ -23,13 +23,16 @@ cypher : statement ';'? EOF ;
 
 statement : query ;
 
-query : regularQuery
+query : cypherQuery
+      | indexQuery
       | explainQuery
       ;
 
-explainQuery : EXPLAIN regularQuery ;
+explainQuery : EXPLAIN cypherQuery ;
 
-regularQuery : singleQuery ( cypherUnion )* ;
+cypherQuery : singleQuery ( cypherUnion )* ;
+
+indexQuery : createIndex ;
 
 singleQuery : clause ( clause )* ;
 
@@ -46,7 +49,6 @@ clause : cypherMatch
        | remove
        | with
        | cypherReturn
-       | createIndex
        ;
 
 cypherMatch : OPTIONAL? MATCH pattern where? ;

src/query/frontend/opencypher/grammar/MemgraphCypher.g4

@@ -45,10 +45,11 @@ symbolicName : UnescapedSymbolicName
              | memgraphCypherKeyword
              ;
 
-query : regularQuery
+query : cypherQuery 
+      | indexQuery
+      | explainQuery
       | authQuery
       | streamQuery
-      | explainQuery
       ;
 
 authQuery : createRole

tests/unit/cypher_main_visitor.cpp

@@ -1510,14 +1510,6 @@ TYPED_TEST(CypherMainVisitorTest, ClausesOrdering) {
                SemanticException);
   TypeParam("UNWIND [1,2,3] AS x CREATE (n) RETURN x");
   TypeParam("CREATE (n) WITH n UNWIND [1,2,3] AS x RETURN x");
-
-  TypeParam("CREATE INDEX ON :a(b)");
-  ASSERT_THROW(TypeParam("CREATE INDEX ON :a(n) CREATE INDEX ON :b(c)"),
-               SemanticException);
-  ASSERT_THROW(TypeParam("CREATE (n) CREATE INDEX ON :a(n)"),
-               SemanticException);
-  ASSERT_THROW(TypeParam("CREATE INDEX ON :a(n) RETURN 2 + 2"),
-               SemanticException);
 }
 
 TYPED_TEST(CypherMainVisitorTest, Merge) {