Never try to create a crs from an empty proj string, just shortcut and mark as invalid instead

nyalldawson · nyalldawson · commit e49b07c70e9f · 2019-05-24T10:24:07.000+10:00
Avoids proj warnings
diff --git a/src/core/qgscoordinatereferencesystem.cpp b/src/core/qgscoordinatereferencesystem.cpp
@@ -796,6 +796,14 @@ bool QgsCoordinateReferenceSystem::createFromProj4( const QString &proj4String )
 {
   d.detach();
 
+  if ( proj4String.trimmed().isEmpty() )
+  {
+    d->mIsValid = false;
+    d->mWkt.clear();
+    d->mProj4.clear();
+    return false;
+  }
+
   sProj4CacheLock.lockForRead();
   QHash< QString, QgsCoordinateReferenceSystem >::const_iterator crsIt = sProj4Cache.constFind( proj4String );
   if ( crsIt != sProj4Cache.constEnd() )
diff --git a/tests/src/core/testqgscoordinatereferencesystem.cpp b/tests/src/core/testqgscoordinatereferencesystem.cpp
@@ -509,6 +509,9 @@ void TestQgsCoordinateReferenceSystem::srsIdCache()
 void TestQgsCoordinateReferenceSystem::createFromProj4()
 {
   QgsCoordinateReferenceSystem myCrs;
+  QVERIFY( !myCrs.createFromProj4( QString() ) );
+  QVERIFY( !myCrs.isValid() );
+
   QVERIFY( myCrs.createFromProj4( GEOPROJ4 ) );
   debugPrint( myCrs );
   QVERIFY( myCrs.isValid() );
