From 251b3aeb2bf8d2b84d09fd677a5d620f84d59459 Mon Sep 17 00:00:00 2001
From: James Turner <james@flightgear.org>
Date: Sat, 13 Mar 2021 15:57:05 +0000
Subject: [PATCH] TimeManager: add unit-test for ETC time zones

Ensure when entering/exiting oceanic areas, we switch to/from an ETC
time-zone correctly
---
 .../unit_tests/Main/test_timeManager.cxx      | 44 +++++++++++++++++++
 .../unit_tests/Main/test_timeManager.hxx      |  2 +
 2 files changed, 46 insertions(+)

diff --git a/test_suite/unit_tests/Main/test_timeManager.cxx b/test_suite/unit_tests/Main/test_timeManager.cxx
index 3798607dd..2f309e988 100644
--- a/test_suite/unit_tests/Main/test_timeManager.cxx
+++ b/test_suite/unit_tests/Main/test_timeManager.cxx
@@ -21,6 +21,7 @@
 #include "test_timeManager.hxx"
 
 #include "test_suite/FGTestApi/NavDataCache.hxx"
+#include "test_suite/FGTestApi/TestPilot.hxx"
 #include "test_suite/FGTestApi/testGlobals.hxx"
 
 #include <simgear/io/iostreams/sgstream.hxx>
@@ -169,6 +170,49 @@ void TimeManagerTests::testTimeZones()
     CPPUNIT_ASSERT_EQUAL((time_t)28800, globals->get_time_params()->get_local_offset());
 }
 
+void TimeManagerTests::testETCTimeZones()
+{
+    auto phto = fgFindAirportID("PHTO");
+    FGTestApi::setPositionAndStabilise(phto->geod());
+    auto timeManager = new TimeManager;
+
+    timeManager->bind();
+    timeManager->init();
+    timeManager->postinit();
+
+    // fake Unix time by setting this; it will then
+    // set the 'current unix time' passed to SGTime
+    const auto testDate = 314611200L;
+    fgSetInt("/sim/time/cur-time-override", testDate);
+
+    globals->add_subsystem("time", timeManager);
+
+    FGTestApi::setPositionAndStabilise(phto->geod());
+    timeManager->reposition();
+    timeManager->update(0.0);
+
+    SGPropertyNode_ptr tzNameNode = fgGetNode("/sim/time/local-timezone", true);
+
+    CPPUNIT_ASSERT_EQUAL((time_t)-36000, globals->get_time_params()->get_local_offset());
+    CPPUNIT_ASSERT_EQUAL("Pacific/Honolulu"s, string{tzNameNode->getStringValue()});
+
+    auto pilot = SGSharedPtr<FGTestApi::TestPilot>(new FGTestApi::TestPilot);
+    pilot->setSpeedKts(1000);
+    pilot->setCourseTrue(320.0);
+
+    bool ok = FGTestApi::runForTimeWithCheck(600.0, [tzNameNode]() {
+        const string tz = tzNameNode->getStringValue();
+        return tz == "Etc/GMT+10"s;
+    });
+    CPPUNIT_ASSERT(ok);
+
+    ok = FGTestApi::runForTimeWithCheck(600.0, [tzNameNode]() {
+        const string tz = tzNameNode->getStringValue();
+        return tz == "Pacific/Honolulu"s;
+    });
+    CPPUNIT_ASSERT(ok);
+}
+
 void TimeManagerTests::testSpecifyTimeOffset()
 {
     // disabled for now since this code depends on epehmeris as well
diff --git a/test_suite/unit_tests/Main/test_timeManager.hxx b/test_suite/unit_tests/Main/test_timeManager.hxx
index 814f41f9e..d2dfc5ed5 100644
--- a/test_suite/unit_tests/Main/test_timeManager.hxx
+++ b/test_suite/unit_tests/Main/test_timeManager.hxx
@@ -33,6 +33,7 @@ class TimeManagerTests : public CppUnit::TestFixture
     CPPUNIT_TEST(testTimeZones);
     CPPUNIT_TEST(testFreezeUnfreeze);
     CPPUNIT_TEST(testSpecifyTimeOffset);
+    CPPUNIT_TEST(testETCTimeZones);
     CPPUNIT_TEST_SUITE_END();
 
 public:
@@ -47,4 +48,5 @@ public:
     void testTimeZones();
     void testFreezeUnfreeze();
     void testSpecifyTimeOffset();
+    void testETCTimeZones();
 };