Fix coverity ignored return value warnings

nyalldawson · nyalldawson · commit 75c99800d0f1 · 2017-12-05T10:34:33.000+10:00
diff --git a/src/core/qgsfiledownloader.cpp b/src/core/qgsfiledownloader.cpp
@@ -174,10 +174,17 @@ void QgsFileDownloader::onFinished()
       QUrl newUrl = mUrl.resolved( redirectionTarget.toUrl() );
       mUrl = newUrl;
       mReply->deleteLater();
-      mFile.open( QIODevice::WriteOnly );
-      mFile.resize( 0 );
-      mFile.close();
-      startDownload();
+      if ( !mFile.open( QIODevice::WriteOnly ) )
+      {
+        mFile.remove();
+        error( tr( "Cannot open output file: %1" ).arg( mFile.fileName() ) );
+      }
+      else
+      {
+        mFile.resize( 0 );
+        mFile.close();
+        startDownload();
+      }
       return;
     }
     else
diff --git a/src/gui/attributetable/qgsattributetablemodel.cpp b/src/gui/attributetable/qgsattributetablemodel.cpp
@@ -289,9 +289,11 @@ void QgsAttributeTableModel::attributeValueChanged( QgsFeatureId fid, int idx, c
   {
     if ( mSortFieldIndex == -1 )
     {
-      loadFeatureAtId( fid );
-      mExpressionContext.setFeature( mFeat );
-      mSortCache[fid] = mSortCacheExpression.evaluate( &mExpressionContext );
+      if ( loadFeatureAtId( fid ) )
+      {
+        mExpressionContext.setFeature( mFeat );
+        mSortCache[fid] = mSortCacheExpression.evaluate( &mExpressionContext );
+      }
     }
     else
     {
diff --git a/src/providers/gdal/qgsgdalprovider.cpp b/src/providers/gdal/qgsgdalprovider.cpp
@@ -187,7 +187,7 @@ QgsGdalProvider::QgsGdalProvider( const QString &uri, bool update, GDALDatasetH
   }
   else
   {
-    initIfNeeded();
+    ( void )initIfNeeded();
   }
 }
 
diff --git a/tests/src/core/testqgsdxfexport.cpp b/tests/src/core/testqgsdxfexport.cpp
@@ -301,7 +301,7 @@ bool TestQgsDxfExport::fileContainsText( const QString &path, const QString &tex
 {
   QStringList searchLines = text.split( '\n' );
   QFile file( path );
-  file.open( QIODevice::ReadOnly );
+  QVERIFY( file.open( QIODevice::ReadOnly ) );
   QTextStream in( &file );
   QString line;
   do

Original file line number	Diff line number	Diff line change
`@@ -289,9 +289,11 @@ void QgsAttributeTableModel::attributeValueChanged( QgsFeatureId fid, int idx, c`
`289`	`289`	`{`
`290`	`290`	`if ( mSortFieldIndex == -1 )`
`291`	`291`	`{`
`292`		`- loadFeatureAtId( fid );`
`293`		`- mExpressionContext.setFeature( mFeat );`
`294`		`- mSortCache[fid] = mSortCacheExpression.evaluate( &mExpressionContext );`
	`292`	`+ if ( loadFeatureAtId( fid ) )`
	`293`	`+ {`
	`294`	`+ mExpressionContext.setFeature( mFeat );`
	`295`	`+ mSortCache[fid] = mSortCacheExpression.evaluate( &mExpressionContext );`
	`296`	`+ }`
`295`	`297`	`}`
`296`	`298`	`else`
`297`	`299`	`{`
Original file line number	Diff line number	Diff line change
`@@ -187,7 +187,7 @@ QgsGdalProvider::QgsGdalProvider( const QString &uri, bool update, GDALDatasetH`
`187`	`187`	`}`
`188`	`188`	`else`
`189`	`189`	`{`
`190`		`- initIfNeeded();`
	`190`	`+ ( void )initIfNeeded();`
`191`	`191`	`}`
`192`	`192`	`}`
`193`	`193`
Original file line number	Diff line number	Diff line change
`@@ -301,7 +301,7 @@ bool TestQgsDxfExport::fileContainsText( const QString &path, const QString &tex`
`301`	`301`	`{`
`302`	`302`	`QStringList searchLines = text.split( '\n' );`
`303`	`303`	`QFile file( path );`
`304`		`- file.open( QIODevice::ReadOnly );`
	`304`	`+ QVERIFY( file.open( QIODevice::ReadOnly ) );`
`305`	`305`	`QTextStream in( &file );`
`306`	`306`	`QString line;`
`307`	`307`	`do`