Changing default install location is not respected

[psulek]

• Electron-Builder Version: 24.13.3
• Node Version: 18.18.2
• Electron Version: 28.1.1
• Electron Type (current, beta, nightly): stable
• Target: NSIS
• OS: Windows 10

According to this custom-nsis-script , in question How do change the default installation directory to custom? there is sample of macro to use to set custom default install location.

I use that successfully with previous version of electron-builder (v20x), but in current version (24x) this functionality is broken.
Same bug was reported in #6369 but was closed due to inactivity ? That problem still persist in latest version.

My observations:
my project uses (till now) version 20.38.5 of electron-builer and when i set custom install location via recommended NSI script:

!macro preInit
    SetRegView 64
    WriteRegExpandStr HKLM "${INSTALL_REGISTRY_KEY}" InstallLocation "c:\MyApp"
    WriteRegExpandStr HKCU "${INSTALL_REGISTRY_KEY}" InstallLocation "c:\MyApp"
    SetRegView 32
    WriteRegExpandStr HKLM "${INSTALL_REGISTRY_KEY}" InstallLocation "c:\MyApp"
    WriteRegExpandStr HKCU "${INSTALL_REGISTRY_KEY}" InstallLocation "c:\MyApp"
!macroend

and productName is MyCompany Super Product and run MSI installer (without changing install location in installer UI) my app is properly installed in c:\MyApp where i can find exe file eg. c:\MyApp\myapp.exe - this is expected and valid

But updating to latest version 24.9.1 with same nsi preInit script, and values, my app is installed into folder c:\MyApp\MyCompany Super Product and exe is found in c:\MyApp\MyCompany Super Product\myapp.exe - this is unexpected and wrong.

I found (thanks to @xyyHIT) what causing this is in file app-builder-lib/templates/nsis/assistedInstaller.nsh and function instFilesPre, where old was:

    Function instFilesPre
      ${If} ${FileExists} "$INSTDIR\*"
        ${StrContains} $0 "${APP_FILENAME}" $INSTDIR
        ${If} $0 == ""
          StrCpy $INSTDIR "$INSTDIR\${APP_FILENAME}"
        ${endIf}
      ${endIf}
    FunctionEnd

but new one has:

    Function instFilesPre
      ${StrContains} $0 "${APP_FILENAME}" $INSTDIR
      ${If} $0 == ""
        StrCpy $INSTDIR "$INSTDIR\${APP_FILENAME}"
      ${endIf}
    FunctionEnd

missing ${If} on first line of function. Maybe this change fixes some other issue or was changed by mistake. Can you elaborate this? For now im stuck on older version.