MuseScore Portable 2.0.3 Upgrade Code.

This started in the Outdated Apps thread, and (rightfully) got deleted from there, as it should have been split off to another thread if it was to continue.

Summary of the discussion so far:

Bart.S: MuseScore

MuseScore 2.0.3 has been released.
It eats some settings on upgrade though.
I'll investigate.

John, maybe you could create a new splash in the meantime:
https://github.com/musescore/MuseScore/blob/2.0.3/mscore/data/splash.png

John T. Haller: Splash

https://portableapps.com/downloads/MuseScorePortable.jpg

Bart.S: Thanks

Thanks for the splash.

I have reported a bug: https://musescore.org/en/node/104936
Maybe they'll fix it soon or I have to create some custom installer code to keep portable paths.

3D1T0R: Try this

This copies the contents of Data\Settings\MuseScore2.ini's [General]:sfPath to [General]:mySoundfontsPath (if [General]:sfPath is present). Is this enough? or do we need to edit the value at all? and/or do we need to remove [General]:sfPath too?

!macro CustomCodePreInstall
	${If} ${FileExists} "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini"
		ReadINIStr $0 "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini" "General" "sfPath"
		StrCmp $0 "" +2
			WriteINIStr "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini" "General" "mySoundfontsPath" '"$0"'
	${EndIf}
!macroend

Bart.S: (Sorry, I forget what exactly this post said, and I the page where I'd looked at it wasn't still open when I went to write this)

Something was said about copying the value may not be enough, and that Bart.S had implemented some "magic", but nothing more specific about it was stated.

Well, here's my reply:

You didn't say what "magic" you'd implemented, and since I'd already started, I kept working on it.

So, after analyzing their source, and a bunch of experimentation, I don't think that just copying it would be a problem, but you're right, we should probably emulate the changes they do in their upgrade code if we can, and I've written a new Other\Source\PortableApps.comInstallerCustom.nsh which does everything their code does, and saves it in the new location.
Also, I think the sfPath shouldn't be removed until the installation is complete (to be safe), so I put that bit in CustomCodePostInstall, and had it check to make sure both sfPath and mySoundfontsPath were present before it would delete it:

!macro CustomCodePreInstall
	${If} ${FileExists} "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini"
		ReadINIStr $0 "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini" "General" "sfPath"
		IfErrors sfPathNotFound

		${WordFind} $0 ";" "#" $1 ; How many folders are there?
		PushSoundFontFolderToStack:
			${WordFind} $0 ";" +$1 $2 ; This is one folder.
			Push $2 ; Push it to the stack.
			IntOp $1 $1 - 1 ; One less to do.
			StrCmp $1 0 0 PushSoundFontFolderToStack ; If there are any left to do, go back and do the next one.

		${WordReplace} "$INSTDIR\App\MuseScore\sound" '\' "/" "+" $3 ; Convert \ to /
		${WordFind} $0 ";" "#" $1 ; We need to know how many folders are there again.
		StrCpy $0 "" ; Clear $0 in preparation to rebuild it.
		PopSoundFontFolderFromStack:
			Pop $2 ; Put one of the folders in $2
			StrCmp $2 $3 +2 ; If $2 is "%PAL:AppDir%\MuseScore\sound", skip next line.
				StrCpy $0 "$0$2;" ; Add it (and a ;) to $0
			IntOp $1 $1 - 1 ; One less to do.
			StrCmp $1 0 0 PopSoundFontFolderFromStack ; If there are any left to do, go back and do the next one.
		StrCpy $0 $0 -1 ; Remove extra ; at end

		${WordFind} $0 ";" "#" $1 ; Now: How many folders are still there?
		IntCmp $1 1 +2 +2 ; If there's only one, skip the next line.
			StrCpy $0 `"$0"` ; Add quotes around $0

		WriteINIStr "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini" "General" "mySoundfontsPath" $0

		sfPathNotFound:
	${EndIf}
!macroend

!macro CustomCodePostInstall
	${If} ${FileExists} "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini"
		ClearErrors
		ReadINIStr $0 "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini" "General" "sfPath"
		ReadINIStr $0 "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini" "General" "mySoundfontsPath"
		IfErrors +2 ; If sfPath or mySoundfontsPath not found, skip next line.
			DeleteINIStr "$INSTDIR\Data\settings\MuseScore\MuseScore2.ini" "General" "sfPath"
	${EndIf}
!macroend

P.S.: I also commented the code pretty heavily to make sure it would be (relatively) easy to follow.