From c03ac224204ad6b586082a2926147a7230269aeb Mon Sep 17 00:00:00 2001
From: Nyall Dawson <nyall.dawson@gmail.com>
Date: Tue, 26 May 2020 10:01:56 +1000
Subject: [PATCH] Add unit test for message bar max item count

---
 src/gui/qgsmessagebar.h             |  2 ++
 tests/src/gui/testqgsmessagebar.cpp | 35 +++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/src/gui/qgsmessagebar.h b/src/gui/qgsmessagebar.h
index 61de6da7410b..21d1aa1dfe0d 100644
--- a/src/gui/qgsmessagebar.h
+++ b/src/gui/qgsmessagebar.h
@@ -268,6 +268,8 @@ class GUI_EXPORT QgsMessageBar: public QFrame
     //! updates the countdown for widgets that have a timeout duration
     void updateCountdown();
     void resetCountdown();
+
+    friend class TestQgsMessageBar;
 };
 
 #endif
diff --git a/tests/src/gui/testqgsmessagebar.cpp b/tests/src/gui/testqgsmessagebar.cpp
index 39f1bc9c966b..4dec119fecca 100644
--- a/tests/src/gui/testqgsmessagebar.cpp
+++ b/tests/src/gui/testqgsmessagebar.cpp
@@ -30,6 +30,7 @@ class TestQgsMessageBar: public QObject
     void cleanup(); // will be called after every testfunction.
     void dismiss();
     void pushPop();
+    void autoDelete();
 
 };
 
@@ -144,5 +145,39 @@ void TestQgsMessageBar::pushPop()
   QVERIFY( !bar.currentItem() );
 }
 
+void TestQgsMessageBar::autoDelete()
+{
+  // ensure that items are automatically deleted when queue grows too large
+  QgsMessageBar bar;
+  for ( int i = 0; i < bar.MAX_ITEMS; ++i )
+  {
+    bar.pushMessage( QString::number( i ), Qgis::Warning );
+  }
+  QCOMPARE( bar.items().size(), 100 );
+  QCOMPARE( bar.items().at( 0 )->text(), QStringLiteral( "99" ) );
+  QCOMPARE( bar.items().at( 99 )->text(), QStringLiteral( "0" ) );
+  QPointer< QgsMessageBarItem > oldest = bar.items().at( 99 );
+
+  // push one more item, oldest one should be auto-removed
+  bar.pushMessage( QStringLiteral( "100" ), Qgis::Warning );
+  QCOMPARE( bar.items().size(), 100 );
+  QCOMPARE( bar.items().at( 0 )->text(), QStringLiteral( "100" ) );
+  QCOMPARE( bar.items().at( 99 )->text(), QStringLiteral( "1" ) );
+  QgsApplication::sendPostedEvents( nullptr, QEvent::DeferredDelete );
+  QVERIFY( !oldest );
+
+  // but if we have a lower priority message we can pop, then do that instead
+  bar.pushMessage( QStringLiteral( "101" ), Qgis::Info );
+  QCOMPARE( bar.items().size(), 100 );
+  QCOMPARE( bar.items().at( 0 )->text(), QStringLiteral( "101" ) );
+  QCOMPARE( bar.items().at( 1 )->text(), QStringLiteral( "100" ) );
+  QCOMPARE( bar.items().at( 99 )->text(), QStringLiteral( "2" ) );
+  bar.pushMessage( QStringLiteral( "102" ), Qgis::Info );
+  QCOMPARE( bar.items().size(), 100 );
+  QCOMPARE( bar.items().at( 0 )->text(), QStringLiteral( "102" ) );
+  QCOMPARE( bar.items().at( 1 )->text(), QStringLiteral( "100" ) );
+  QCOMPARE( bar.items().at( 99 )->text(), QStringLiteral( "2" ) );
+}
+
 QGSTEST_MAIN( TestQgsMessageBar )
 #include "testqgsmessagebar.moc"