From ea202dc52a8a7803b484532e2c7f91a560fc75c3 Mon Sep 17 00:00:00 2001
From: florijan <florijan@memgraph.io>
Date: Wed, 12 Apr 2017 09:01:44 +0200
Subject: [PATCH] Query::Plan::EdgeFilter bugfix

Summary:
Resolved the bug where edge filters with no edge-types dont accept any edge.
Illustrated with the following queries:
CREATE ()-[]->()
MATCH ()-[]->()
	(produces 0 results, expected 1)

Reviewers: mislav.bradac

Reviewed By: mislav.bradac

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D265
---
 src/query/frontend/logical/operator.cpp       |  4 ++--
 tests/unit/query_plan_match_filter_return.cpp | 20 +++++++++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/query/frontend/logical/operator.cpp b/src/query/frontend/logical/operator.cpp
index 0c088b223..b1e3666b9 100644
--- a/src/query/frontend/logical/operator.cpp
+++ b/src/query/frontend/logical/operator.cpp
@@ -427,8 +427,8 @@ bool EdgeFilter::EdgeFilterCursor::EdgePasses(const EdgeAccessor &edge,
   // edge type filtering - logical OR
   const auto &types = self_.edge_atom_->edge_types_;
   GraphDbTypes::EdgeType type = edge.edge_type();
-  if (!std::any_of(types.begin(), types.end(),
-                   [type](auto t) { return t == type; }))
+  if (types.size() && std::none_of(types.begin(), types.end(),
+                                   [type](auto t) { return t == type; }))
     return false;
 
   ExpressionEvaluator expression_evaluator(frame, symbol_table);
diff --git a/tests/unit/query_plan_match_filter_return.cpp b/tests/unit/query_plan_match_filter_return.cpp
index 696307e8c..09ba73614 100644
--- a/tests/unit/query_plan_match_filter_return.cpp
+++ b/tests/unit/query_plan_match_filter_return.cpp
@@ -388,6 +388,26 @@ TEST(QueryPlan, EdgeFilter) {
   EXPECT_EQ(result.GetResults().size(), 1);
 }
 
+TEST(QueryPlan, EdgeFilterEmpty) {
+  Dbms dbms;
+  auto dba = dbms.active();
+
+  auto v1 = dba->insert_vertex();
+  auto v2 = dba->insert_vertex();
+  dba->insert_edge(v1, v2, dba->edge_type("type"));
+  dba->advance_command();
+
+  AstTreeStorage storage;
+  SymbolTable symbol_table;
+
+  auto n = MakeScanAll(storage, symbol_table, "n");
+  auto r_m = MakeExpand(storage, symbol_table, n.op_, n.sym_, "r",
+                        EdgeAtom::Direction::RIGHT, false, "m", false);
+  auto edge_filter =
+      std::make_shared<EdgeFilter>(r_m.op_, r_m.edge_sym_, r_m.edge_);
+  EXPECT_EQ(1, PullAll(edge_filter, *dba, symbol_table));
+}
+
 TEST(QueryPlan, EdgeFilterMultipleTypes) {
   Dbms dbms;
   auto dba = dbms.active();