Midi Import Crashes, Export Fails (Possible Fix Included)

[McLP2]

I seem to be one of the few users to use the MIDI import/export feature as part of my song-mapping pipeline, so thanks for not removing it! :D

After updating from an old version however, I noticed and debugged multiple regressions:

• Exporting always fails due to nil FormatVersion in Song
• Opening a MIDI file without a tempo message crashes due to Nan current-time text position

I could fix them locally with the following patch on commit 61c5349:

diff --git a/src/base/USong.pas b/src/base/USong.pas
index e0c365e5..2276bcd9 100644
--- a/src/base/USong.pas
+++ b/src/base/USong.pas
@@ -389,6 +389,8 @@ constructor TSong.Create();
   Self.Vocals   := PATH_NONE();
   Self.Background:= PATH_NONE();
   Self.Video    := PATH_NONE();
+
+  Self.FormatVersion := TVersion.Create();
 end;
 
 // This may be changed, when we rewrite song select code.
diff --git a/src/screens/UScreenEditConvert.pas b/src/screens/UScreenEditConvert.pas
index ca6ece76..5bcbfe8d 100644
--- a/src/screens/UScreenEditConvert.pas
+++ b/src/screens/UScreenEditConvert.pas
@@ -837,6 +837,11 @@ procedure TScreenEditConvert.OnShow;
     MidiFile.Filename := fFileName;
     try
       MidiFile.ReadFile;
+      // midi file might not contain any tempo messages, default to 120 bpm
+      if MidiFile.GetFusPerTick = 0.0 then
+      begin
+        MidiFile.Bpm := 120;
+      end;
       FileOpened := true;
     except
       MidiFile.Free;

[dgruss]

These changes look reasonable to me, why don't you open a pull request?