bug 2081 - Frequencies added to labels

Mitigate bug by making old label format the default
and the addition of frequency ranges optional.

src/LabelTrack.cpp

@@ -45,6 +45,7 @@ for drawing different aspects of the label and its text box.
 
 #include "Prefs.h"
 #include "ProjectFileIORegistry.h"
+#include "prefs/ImportExportPrefs.h"
 
 #include "effects/TimeWarper.h"
 #include "widgets/AudacityMessageBox.h"
@@ -443,8 +444,9 @@ void LabelStruct::Export(wxTextFile &file) const
    // Do we need more lines?
    auto f0 = selectedRegion.f0();
    auto f1 = selectedRegion.f1();
-   if (f0 == SelectedRegion::UndefinedFrequency &&
-       f1 == SelectedRegion::UndefinedFrequency)
+   if ((f0 == SelectedRegion::UndefinedFrequency &&
+      f1 == SelectedRegion::UndefinedFrequency) ||
+      ImportExportPrefs::LabelStyleSetting.ReadEnum())
       return;
 
    // Write a \ character at the start of a second line,

src/prefs/ImportExportPrefs.cpp

@@ -76,6 +76,19 @@ EnumSetting< bool > ImportExportPrefs::ExportDownMixSetting{
    wxT("/FileFormats/ExportDownMix"),
 };
 
+EnumSetting< bool > ImportExportPrefs::LabelStyleSetting{
+   wxT("/FileFormats/LabelStyleChoice"),
+   {
+      EnumValueSymbol{ wxT("Standard"), XXO("S&tandard") },
+      EnumValueSymbol{ wxT("Extended"), XXO("E&xtended (with frequency ranges)") },
+   },
+   0, // true
+
+   {
+      true, false,
+   },
+};
+
 EnumSetting< bool > ImportExportPrefs::AllegroStyleSetting{
    wxT("/FileFormats/AllegroStyleChoice"),
    {
@@ -114,6 +127,18 @@ void ImportExportPrefs::PopulateOrExchange(ShuttleGui & S)
                      false});
    }
    S.EndStatic();
+
+   S.StartStatic(XO("Exported Label Style:"));
+   {
+      S.StartRadioButtonGroup(ImportExportPrefs::LabelStyleSetting);
+      {
+         S.TieRadioButton();
+         S.TieRadioButton();
+      }
+      S.EndRadioButtonGroup();
+   }
+   S.EndStatic();
+
 #ifdef USE_MIDI
    S.StartStatic(XO("Exported Allegro (.gro) files save time as:"));
    {

src/prefs/ImportExportPrefs.h

@@ -27,6 +27,7 @@ class ImportExportPrefs final : public PrefsPanel
 {
  public:
    static EnumSetting< bool > ExportDownMixSetting;
+   static EnumSetting< bool > LabelStyleSetting;
    static EnumSetting< bool > AllegroStyleSetting;
 
    ImportExportPrefs(wxWindow * parent, wxWindowID winid);