How to force Inno Setup setup to fail when Run command fails?

Question

I have some commands in the [Run] section of my Inno Setup script. Right now, if any of them returns a failure code (non-zero return value), the setup continue

Answer 1

The [Run] section happens after installation is complete, so there's no rollback possible at that point, because it's already finalized.

However, what you can do is use AfterInstall in the [Files] section, after your .exe or whatever is required to execute your method. This runs before finalizing the installation, so canceling at this point does a rollback that removes all files.

If you combine that with the "CancelWithoutPrompt" from this answer you can do a rollback when running in interactive mode. Unfortunately, there doesn't seem to be a rollback for silent mode.

[Files]
Source: src\myapp.exe; DestDir: "{app}"; AfterInstall: RunMyAppCheck

[Code]
var CancelWithoutPrompt: boolean;

function InitializeSetup(): Boolean;
begin
  CancelWithoutPrompt := false;
  result := true;
end;

procedure CancelButtonClick(CurPageID: Integer; var Cancel, Confirm: Boolean);
begin
  if CancelWithoutPrompt then
    Confirm := false; { hide confirmation prompt }
end;

procedure RunMyAppCheck();
var
  resultCode: int;
begin
  Exec(ExpandConstant('{app}\myapp.exe'), '--verify --example-other-params',
    '', SW_HIDE, ewWaitUntilTerminated, resultCode);
  
  if resultCode <> 0 then
  begin
    SuppressibleMsgBox(
      'MyApp failed, exit code ' + IntToStr(resultCode) + '. Aborting installation.',
      mbCriticalError, MB_OK, 0);
  
    CancelWithoutPrompt := true;
    WizardForm.Close;
  end;
end;