memgraph/tests/unit/query_plan_edge_cases.cpp
2021-07-22 16:22:08 +02:00

97 lines
3.1 KiB
C++

// tests in this suite deal with edge cases in logical operator behavior
// that's not easily testable with single-phase testing. instead, for
// easy testing and latter readability they are tested end-to-end.
#include <filesystem>
#include <optional>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "communication/result_stream_faker.hpp"
#include "query/interpreter.hpp"
#include "storage/v2/storage.hpp"
DECLARE_bool(query_cost_planner);
class QueryExecution : public testing::Test {
protected:
std::optional<storage::Storage> db_;
std::optional<query::InterpreterContext> interpreter_context_;
std::optional<query::Interpreter> interpreter_;
std::filesystem::path data_directory{std::filesystem::temp_directory_path() / "MG_tests_unit_query_plan_edge_cases"};
void SetUp() {
db_.emplace();
interpreter_context_.emplace(&*db_, query::InterpreterConfig{}, data_directory, "non existing bootstrap servers");
interpreter_.emplace(&*interpreter_context_);
}
void TearDown() {
interpreter_ = std::nullopt;
interpreter_context_ = std::nullopt;
db_ = std::nullopt;
}
/**
* Execute the given query and commit the transaction.
*
* Return the query results.
*/
auto Execute(const std::string &query) {
ResultStreamFaker stream(&*db_);
auto [header, _, qid] = interpreter_->Prepare(query, {}, nullptr);
stream.Header(header);
auto summary = interpreter_->PullAll(&stream);
stream.Summary(summary);
return stream.GetResults();
}
};
TEST_F(QueryExecution, MissingOptionalIntoExpand) {
// validating bug where expanding from Null (due to a preceeding optional
// match) exhausts the expansion cursor, even if it's input is still not
// exhausted
Execute(
"CREATE (a:Person {id: 1}), (b:Person "
"{id:2})-[:Has]->(:Dog)-[:Likes]->(:Food )");
ASSERT_EQ(Execute("MATCH (n) RETURN n").size(), 4);
auto Exec = [this](bool desc, const std::string &edge_pattern) {
// this test depends on left-to-right query planning
FLAGS_query_cost_planner = false;
return Execute(std::string("MATCH (p:Person) WITH p ORDER BY p.id ") + (desc ? "DESC " : "") +
"OPTIONAL MATCH (p)-->(d:Dog) WITH p, d "
"MATCH (d)" +
edge_pattern +
"(f:Food) "
"RETURN p, d, f")
.size();
};
std::string expand = "-->";
std::string variable = "-[*1]->";
std::string bfs = "-[*bfs..1]->";
EXPECT_EQ(Exec(false, expand), 1);
EXPECT_EQ(Exec(true, expand), 1);
EXPECT_EQ(Exec(false, variable), 1);
EXPECT_EQ(Exec(true, bfs), 1);
EXPECT_EQ(Exec(true, bfs), 1);
}
TEST_F(QueryExecution, EdgeUniquenessInOptional) {
// Validating that an edge uniqueness check can't fail when the edge is Null
// due to optonal match. Since edge-uniqueness only happens in one OPTIONAL
// MATCH, we only need to check that scenario.
Execute("CREATE (), ()-[:Type]->()");
ASSERT_EQ(Execute("MATCH (n) RETURN n").size(), 3);
EXPECT_EQ(Execute("MATCH (n) OPTIONAL MATCH (n)-[r1]->(), (n)-[r2]->() "
"RETURN n, r1, r2")
.size(),
3);
}