Use QLocale when representing double fields

Author: elpaso

src/core/qgsfield.cpp

@@ -22,6 +22,7 @@
 
 #include <QDataStream>
 #include <QIcon>
+#include <QLocale>
 
 /***************************************************************************
  * This class is considered CRITICAL and any change MUST be accompanied with
@@ -208,8 +209,30 @@ QString QgsField::displayString( const QVariant &v ) const
     return QgsApplication::nullRepresentation();
   }
 
-  if ( d->type == QVariant::Double && d->precision > 0 )
-    return QString::number( v.toDouble(), 'f', d->precision );
+  if ( d->type == QVariant::Double )
+  {
+    if ( d->precision > 0 )
+    {
+      return QLocale().toString( v.toDouble(), 'f', d->precision );
+    }
+    else
+    {
+      // Precision is not set, let's guess it from the
+      // standard conversion to string
+      QString s( v.toString() );
+      int dotPosition( s.indexOf( '.' ) );
+      int precision;
+      if ( dotPosition < 0 )
+      {
+        precision = 0;
+      }
+      else
+      {
+        precision = s.length() - dotPosition - 1;
+      }
+      return QLocale().toString( v.toDouble(), 'f', precision );
+    }
+  }
 
   return v.toString();
 }

tests/src/core/testqgsfield.cpp

@@ -17,6 +17,7 @@
 #include <QObject>
 #include <QString>
 #include <QStringList>
+#include <QLocale>
 
 #include <memory>
 
@@ -66,12 +67,12 @@ void TestQgsField::cleanupTestCase()
 
 void TestQgsField::init()
 {
-
+  QLocale::setDefault( QLocale::English );
 }
 
 void TestQgsField::cleanup()
 {
-
+  QLocale::setDefault( QLocale::English );
 }
 
 void TestQgsField::create()
@@ -332,12 +333,20 @@ void TestQgsField::displayString()
   QgsField doubleFieldNoPrec( QStringLiteral( "double" ), QVariant::Double, QStringLiteral( "double" ), 10 );
   QCOMPARE( doubleFieldNoPrec.displayString( 5.005005 ), QString( "5.005005" ) );
   QCOMPARE( doubleFieldNoPrec.displayString( 5.005005005 ), QString( "5.005005005" ) );
-  QCOMPARE( doubleFieldNoPrec.displayString( 599999898999.0 ), QString( "599999898999" ) );
+  QCOMPARE( doubleFieldNoPrec.displayString( 599999898999.0 ), QString( "599,999,898,999" ) );
 
   //test NULL double
   QVariant nullDouble = QVariant( QVariant::Double );
   QCOMPARE( doubleField.displayString( nullDouble ), QString( "TEST NULL" ) );
 
+  //test double value with German locale
+  QLocale::setDefault( QLocale::German );
+  QCOMPARE( doubleField.displayString( 5.005005 ), QString( "5,005" ) );
+  QCOMPARE( doubleFieldNoPrec.displayString( 5.005005 ), QString( "5,005005" ) );
+  QCOMPARE( doubleFieldNoPrec.displayString( 5.005005005 ), QString( "5,005005005" ) );
+  QCOMPARE( doubleFieldNoPrec.displayString( 599999898999.0 ), QString( "599.999.898.999" ) );
+
+
 }
 
 void TestQgsField::convertCompatible()