Fix incorrect coalesce() output when one input range is wholly

covered by another.

4 files changed, 41 insertions, 3 deletions

diff --git a/src/lib/dcpomatic_time_coalesce.h b/src/lib/dcpomatic_time_coalesce.h
index e6e16641e..56f82bcb6 100644
--- a/src/lib/dcpomatic_time_coalesce.h
+++ b/src/lib/dcpomatic_time_coalesce.h
@@ -32,11 +32,11 @@ std::list<TimePeriod<T> > coalesce (std::list<TimePeriod<T> > periods)
 	do {
 		coalesced.clear ();
 		did_something = false;
-		for (typename std::list<TimePeriod<T> >::const_iterator i = periods.begin(); i != periods.end(); ++i) {
-			typename std::list<TimePeriod<T> >::const_iterator j = i;
+		for (auto i = periods.begin(); i != periods.end(); ++i) {
+			auto j = i;
 			++j;
 			if (j != periods.end() && (i->overlap(*j) || i->to == j->from)) {
-				coalesced.push_back (TimePeriod<T> (i->from, j->to));
+				coalesced.push_back(TimePeriod<T>(std::min(i->from, j->from), std::max(i->to, j->to)));
 				did_something = true;
 				++i;
 			} else {
diff --git a/src/lib/empty.h b/src/lib/empty.h
index 2a975562a..443d3322b 100644
--- a/src/lib/empty.h
+++ b/src/lib/empty.h
@@ -29,6 +29,7 @@
 struct empty_test1;
 struct empty_test2;
 struct empty_test3;
+struct empty_test_with_overlapping_content;
 struct player_subframe_test;
 
 class Empty
@@ -51,6 +52,7 @@ private:
 	friend struct ::empty_test1;
 	friend struct ::empty_test2;
 	friend struct ::empty_test3;
+	friend struct ::empty_test_with_overlapping_content;
 	friend struct ::player_subframe_test;
 
 	std::list<dcpomatic::DCPTimePeriod> _periods;
diff --git a/test/dcpomatic_time_test.cc b/test/dcpomatic_time_test.cc
index e4383b539..5d23f2478 100644
--- a/test/dcpomatic_time_test.cc
+++ b/test/dcpomatic_time_test.cc
@@ -302,6 +302,18 @@ BOOST_AUTO_TEST_CASE (dcpomatic_time_period_coalesce_test5)
 	BOOST_CHECK (q.back()  == DCPTimePeriod(DCPTime(100), DCPTime(106)));
 }
 
+BOOST_AUTO_TEST_CASE (test_coalesce_with_overlapping_periods)
+{
+	DCPTimePeriod A (DCPTime(0), DCPTime(10));
+	DCPTimePeriod B (DCPTime(2), DCPTime(8));
+	list<DCPTimePeriod> p;
+	p.push_back (A);
+	p.push_back (B);
+	auto q = coalesce(p);
+	BOOST_REQUIRE_EQUAL (q.size(), 1U);
+	BOOST_CHECK (q.front() == DCPTimePeriod(DCPTime(0), DCPTime(10)));
+}
+
 /* Straightforward test of DCPTime::ceil */
 BOOST_AUTO_TEST_CASE (dcpomatic_time_ceil_test)
 {
diff --git a/test/empty_test.cc b/test/empty_test.cc
index 9f55499da..8a42bd6b8 100644
--- a/test/empty_test.cc
+++ b/test/empty_test.cc
@@ -35,6 +35,7 @@
 #include <boost/test/unit_test.hpp>
 
 using std::list;
+using std::make_shared;
 using std::shared_ptr;
 #if BOOST_VERSION >= 106100
 using namespace boost::placeholders;
@@ -149,3 +150,26 @@ BOOST_AUTO_TEST_CASE (empty_test3)
 	BOOST_CHECK (black.position() == DCPTime::from_frames(0, vfr));
 }
 
+BOOST_AUTO_TEST_CASE (empty_test_with_overlapping_content)
+{
+	auto film = new_test_film2 ("empty_test_with_overlapping_content");
+	film->set_sequence (false);
+	auto contentA = make_shared<ImageContent>("test/data/simple_testcard_640x480.png");
+	auto contentB = make_shared<ImageContent>("test/data/simple_testcard_640x480.png");
+
+	film->examine_and_add_content (contentA);
+	film->examine_and_add_content (contentB);
+	BOOST_REQUIRE (!wait_for_jobs());
+
+	int const vfr = film->video_frame_rate ();
+
+	contentA->video->set_length (vfr * 3);
+	contentA->set_position (film, DCPTime());
+	contentB->video->set_length (vfr * 1);
+	contentB->set_position (film, DCPTime::from_seconds(1));
+
+	Empty black(film, film->playlist(), bind(&has_video, _1), film->playlist()->length(film));
+
+	BOOST_REQUIRE (black._periods.empty());
+}
+