ZeroTierOne/ext/libpqxx-7.7.3/test/test10.cxx
2022-06-24 10:12:36 -07:00

107 lines
2.9 KiB
C++

#include <cstdio>
#include <iostream>
#include <vector>
#include <pqxx/nontransaction>
#include "test_helpers.hxx"
using namespace pqxx;
// Test program for libpqxx. Open connection to database, start a transaction,
// abort it, and verify that it "never happened."
namespace
{
// Let's take a boring year that is not going to be in the "pqxxevents" table
constexpr int BoringYear{1977};
std::string const Table("pqxxevents");
// Count events, and boring events, in table
std::pair<int, int> CountEvents(transaction_base &T)
{
std::string const events_query{"SELECT count(*) FROM " + Table};
std::string const boring_query{
events_query + " WHERE year=" + to_string(BoringYear)};
return std::make_pair(
T.query_value<int>(events_query), T.query_value<int>(boring_query));
}
// Try adding a record, then aborting it, and check whether the abort was
// performed correctly.
void Test(connection &C, bool ExplicitAbort)
{
std::pair<int, int> EventCounts;
// First run our doomed transaction. This will refuse to run if an event
// exists for our Boring Year.
{
// Begin a transaction acting on our current connection; we'll abort it
// later though.
work Doomed{C, "Doomed"};
// Verify that our Boring Year was not yet in the events table
EventCounts = CountEvents(Doomed);
PQXX_CHECK_EQUAL(
EventCounts.second, 0, "Can't run, boring year is already in table.");
// Now let's try to introduce a row for our Boring Year
Doomed.exec0(
"INSERT INTO " + Table +
"(year, event) "
"VALUES (" +
to_string(BoringYear) + ", 'yawn')");
auto const Recount{CountEvents(Doomed)};
PQXX_CHECK_EQUAL(
Recount.second, 1, "Wrong # events for " + to_string(BoringYear));
PQXX_CHECK_EQUAL(
Recount.first, EventCounts.first + 1, "Number of events changed.");
// Okay, we've added an entry but we don't really want to. Abort it
// explicitly if requested, or simply let the Transaction object "expire."
if (ExplicitAbort)
Doomed.abort();
// If now explicit abort requested, Doomed Transaction still ends here
}
// Now check that we're back in the original state. Note that this may go
// wrong if somebody managed to change the table between our two
// transactions.
work Checkup(C, "Checkup");
auto const NewEvents{CountEvents(Checkup)};
PQXX_CHECK_EQUAL(
NewEvents.first, EventCounts.first,
"Number of events changed. This may be due to a bug in libpqxx, "
"or the test table was modified by some other process.");
PQXX_CHECK_EQUAL(
NewEvents.second, 0,
"Found unexpected events. This may be due to a bug in libpqxx, "
"or the test table was modified by some other process.");
}
void test_abort()
{
connection conn;
nontransaction t{conn};
test::create_pqxxevents(t);
connection &c(t.conn());
t.commit();
Test(c, true);
Test(c, false);
}
PQXX_REGISTER_TEST(test_abort);
} // namespace