DWScript: Issue updating to current development version - dwscript

Question

This weekend, I updated my code base from DWScript SVN. I used Preview 2.7 and now I'm using up-to-date trunk version.
I recompile my application and now the OnAfterInitUnitTable is no more triggered. Actually TdwsUnit.InitUnitTable is not called at all.
BTW: TDWSunit is created at runtime by code and then two classes are exposed using ExposeRTTI. In need to expose one instance of each class.
What are - now - the prerequisites to have OnAfterInitUnitTable triggered?
Any help appreciated.
EDIT: Sample code to reproduce:
program ExposeTest;
{$APPTYPE CONSOLE}
{$R *.res}
uses
SysUtils, Classes, TypInfo,
dwsRTTIExposer, dwsExprs, dwsComp;
type
TScriptApplication = class(TPersistent)
end;
TTestClass = class(TThread)
private
FScript : IdwsProgram;
FDelphiWebScript : TDelphiWebScript;
FUnit : TdwsUnit;
FScriptApplication : TScriptApplication;
FSuccess : Boolean;
procedure ExposeInstancesAfterInitTable(Sender: TObject);
public
constructor Create;
destructor Destroy; override;
procedure Execute; override;
end;
var
Test : TTestClass;
{ TTestClass }
constructor TTestClass.Create;
begin
inherited Create(TRUE);
FScriptApplication := TScriptApplication.Create;
FDelphiWebScript := TDelphiWebScript.Create(nil);
FUnit := TdwsUnit.Create(nil);
FUnit.UnitName := 'Test';
FUnit.Script := FDelphiWebScript;
FUnit.ExposeRTTI(TypeInfo(TScriptApplication), [eoNoFreeOnCleanup]);
FUnit.OnAfterInitUnitTable := ExposeInstancesAfterInitTable;
end;
destructor TTestClass.Destroy;
begin
FreeAndNil(FScriptApplication);
FreeAndNil(FUnit);
FreeAndNil(FDelphiWebScript);
inherited;
end;
procedure TTestClass.Execute;
begin
WriteLn('Test 1');
FSuccess := FALSE;
FScript := FDelphiWebScript.Compile('Unit Test; var I: Integer; I := 0;');
if FSuccess then
WriteLn(' Success')
else
WriteLn(' Failure');
WriteLn('Test 2');
FSuccess := FALSE;
FScript := FDelphiWebScript.Compile('var I: Integer; I := 0;');
if FSuccess then
WriteLn(' Success')
else
WriteLn(' Failure');
WriteLn('Test Done');
end;
procedure TTestClass.ExposeInstancesAfterInitTable(Sender: TObject);
begin
FUnit.ExposeInstanceToUnit('Application', 'TScriptApplication', FScriptApplication);
WriteLn('OnAfterInitUnitTable called');
FSuccess := TRUE;
end;
begin
Test := TTestClass.Create;
Test.Start;
Sleep(1000);
WriteLn('Hit enter to quit');
ReadLn;
Test.Free;
end.
EDIt2: Other version to show the new issue using suggestion by Eric Grange in answer 1 below;
program ExposeTest;
{$APPTYPE CONSOLE}
{$R *.res}
uses
SysUtils, Classes, TypInfo,
dwsRTTIExposer, dwsFunctions, dwsExprs, dwsComp;
type
TScriptApplication = class(TPersistent)
published
procedure Demo;
end;
TTestClass = class(TThread)
private
FScript : IdwsProgram;
FDelphiWebScript : TDelphiWebScript;
FUnit : TdwsUnit;
FScriptApplication : TScriptApplication;
FSuccess : Boolean;
procedure ExposeInstancesAfterInitTable(Sender: TObject);
function NeedUnitHandler(const UnitName : UnicodeString;
var UnitSource : UnicodeString): IdwsUnit;
public
constructor Create;
destructor Destroy; override;
procedure Execute; override;
end;
var
Test : TTestClass;
{ TTestClass }
constructor TTestClass.Create;
begin
inherited Create(TRUE);
FScriptApplication := TScriptApplication.Create;
FDelphiWebScript := TDelphiWebScript.Create(nil);
FDelphiWebScript.OnNeedUnit := NeedUnitHandler;
FUnit := TdwsUnit.Create(nil);
FUnit.UnitName := 'Test';
FUnit.Script := FDelphiWebScript;
FUnit.ExposeRTTI(TypeInfo(TScriptApplication), [eoNoFreeOnCleanup]);
FUnit.OnAfterInitUnitTable := ExposeInstancesAfterInitTable;
end;
destructor TTestClass.Destroy;
begin
FreeAndNil(FScriptApplication);
FreeAndNil(FUnit);
FreeAndNil(FDelphiWebScript);
inherited;
end;
procedure TTestClass.Execute;
begin
WriteLn('Test 1');
FSuccess := FALSE;
FScript := FDelphiWebScript.Compile('Unit Test; var I: Integer; I := 0;');
WriteLn(FScript.Msgs.AsInfo);
if FSuccess then
WriteLn(' Success')
else
WriteLn(' Failure');
WriteLn('Test 2');
FSuccess := FALSE;
FScript := FDelphiWebScript.Compile('uses Other;');
WriteLn(FScript.Msgs.AsInfo);
if FSuccess then
WriteLn(' Success')
else
WriteLn(' Failure');
WriteLn('Test Done');
end;
procedure TTestClass.ExposeInstancesAfterInitTable(Sender: TObject);
begin
FUnit.ExposeInstanceToUnit('Application', 'TScriptApplication', FScriptApplication);
WriteLn('OnAfterInitUnitTable called');
FSuccess := TRUE;
end;
function TTestClass.NeedUnitHandler(
const UnitName : UnicodeString;
var UnitSource : UnicodeString): IdwsUnit;
begin
Result := nil;
if SameText(UnitName, 'Other') then
UnitSource := 'unit Other;' + #13#10 +
'procedure Func;' + #13#10 +
'begin' + #13#10 +
' Application.Demo;' + #13#10 +
'end;' + #13#10
else
UnitSource := '';
end;
{ TScriptApplication }
procedure TScriptApplication.Demo;
begin
end;
begin
Test := TTestClass.Create;
Test.Start;
Sleep(1000);
WriteLn('Hit enter to quit');
ReadLn;
Test.Free;
end.

Answer 1

When encountering a "unit" as main program, the compiler currently assumes it's just a compilation for IDE purposes, ie. to check for syntax errors, build a symbol map, provide suggestions, etc. and the resulting program isn't fully initialized as a consequence.
So if you want to compile the unit and make an executable program, you can have a main program that'll just be something like:
uses Test;
This will compile a program comprised of your unit, for which executions can be created and where functions can be called though exec.Info, classes can be instantiated, etc.
Edit2: For the second test case, it works if "uses Test;" is added. For full cross-compilability with Delphi, you'll also need interface/implementation sections (when targeting script only, they are not necessary)
unit Other;
interface
uses Test;
procedure Func;
implementation
procedure Func;
begin
Application.Demo;
end;
and if RTTI is generated for the methods with the $RTTI directive, at least with
{$RTTI EXPLICIT METHODS([vcPublished])}
TScriptApplication = class(TPersistent)
published
procedure Demo;
end;
otherwise you get an error about "Demo" not being found.