Correctly handle when either min or max map layer scale visibility

is set to 0

0 is intrepreted as "no limit"

Author: nyalldawson

src/core/qgsmaplayer.cpp

@@ -873,7 +873,9 @@ void QgsMapLayer::connectNotify( const char *signal )
 
 bool QgsMapLayer::isInScaleRange( double scale ) const
 {
-  return !mScaleBasedVisibility || ( mMinScale * Qgis::SCALE_PRECISION < scale && scale < mMaxScale );
+  return !mScaleBasedVisibility ||
+         ( ( mMinScale == 0 || mMinScale * Qgis::SCALE_PRECISION < scale )
+           && ( mMaxScale == 0 || scale < mMaxScale ) );
 }
 
 bool QgsMapLayer::hasScaleBasedVisibility() const

tests/src/core/testqgsmaplayer.cpp

@@ -69,6 +69,7 @@ class TestQgsMapLayer : public QObject
 
     void isInScaleRange_data();
     void isInScaleRange();
+    void isInScaleRange2();
 
     void layerRef();
     void layerRefListUtils();
@@ -155,7 +156,27 @@ void TestQgsMapLayer::isInScaleRange()
   //always in scale range if scale based visibility is false
   mpLayer->setScaleBasedVisibility( false );
   QCOMPARE( mpLayer->isInScaleRange( scale ), true );
+}
+
+void TestQgsMapLayer::isInScaleRange2()
+{
+  mpLayer->setMinimumScale( 5000.0 );
+  mpLayer->setMaximumScale( 0.0 );
+  mpLayer->setScaleBasedVisibility( true );
+  QVERIFY( !mpLayer->isInScaleRange( 1000 ) );
+  QVERIFY( !mpLayer->isInScaleRange( 1 ) );
+  QVERIFY( !mpLayer->isInScaleRange( 4999 ) );
+  QVERIFY( mpLayer->isInScaleRange( 5001 ) );
+  QVERIFY( mpLayer->isInScaleRange( 15000 ) );
 
+  mpLayer->setMinimumScale( 0.0 );
+  mpLayer->setMaximumScale( 5000.0 );
+  mpLayer->setScaleBasedVisibility( true );
+  QVERIFY( mpLayer->isInScaleRange( 1000 ) );
+  QVERIFY( mpLayer->isInScaleRange( 1 ) );
+  QVERIFY( mpLayer->isInScaleRange( 4999 ) );
+  QVERIFY( !mpLayer->isInScaleRange( 5001 ) );
+  QVERIFY( !mpLayer->isInScaleRange( 15000 ) );
 }
 
 void TestQgsMapLayer::layerRef()