Add final and sealed as class options

Author: RicardoLuis0

src/common/engine/sc_man_scanner.re

@@ -204,6 +204,7 @@ std2:
 		'stop'						{ RET(TK_Stop); }
 		'null'						{ RET(TK_Null); }
 		'nullptr'					{ RET(ParseVersion >= MakeVersion(4, 9, 0)? TK_Null : TK_Identifier); }
+		'sealed'					{ RET(ParseVersion >= MakeVersion(4, 12, 0)? TK_Sealed : TK_Identifier); }
 
 		'is'						{ RET(ParseVersion >= MakeVersion(1, 0, 0)? TK_Is : TK_Identifier); }
 		'replaces'					{ RET(ParseVersion >= MakeVersion(1, 0, 0)? TK_Replaces : TK_Identifier); }

src/common/engine/sc_man_tokens.h

@@ -122,6 +122,7 @@ xx(TK_Null,					"'null'")
 xx(TK_Global,				"'global'")
 xx(TK_Stop,					"'stop'")
 xx(TK_Include,				"'include'")
+xx(TK_Sealed,				"'sealed'")
 
 xx(TK_Is,					"'is'")
 xx(TK_Replaces,				"'replaces'")

src/common/objects/dobjtype.h

@@ -66,11 +66,14 @@ class PClass
 	bool				 bRuntimeClass = false;	// class was defined at run-time, not compile-time
 	bool				 bDecorateClass = false;	// may be subject to some idiosyncracies due to DECORATE backwards compatibility
 	bool				 bAbstract = false;
+	bool				 bSealed = false;
+	bool				 bFinal = false;
 	bool				 bOptional = false;
 	TArray<VMFunction*>	 Virtuals;	// virtual function table
 	TArray<FTypeAndOffset> MetaInits;
 	TArray<FTypeAndOffset> SpecialInits;
 	TArray<PField *> Fields;
+	TArray<FName> SealedRestriction;
 	PClassType			*VMType = nullptr;
 
 	void (*ConstructNative)(void *);

src/common/scripting/frontend/zcc-parse.lemon

@@ -78,6 +78,7 @@ static void SetNodeLine(ZCC_TreeNode *name, int line)
 	struct ClassFlagsBlock {
 		VM_UWORD Flags;
 		ZCC_Identifier *Replaces;
+		ZCC_Identifier *Sealed;
 		VersionInfo Version;
 	};
 
@@ -242,6 +243,7 @@ class_head(X) ::= CLASS(T) IDENTIFIER(A) class_ancestry(B) class_flags(C).
 	head->ParentName = B;
 	head->Flags = C.Flags;
 	head->Replaces = C.Replaces;
+	head->Sealed = C.Sealed;
 	head->Version = C.Version;
 	head->Type = nullptr;
 	head->Symbol = nullptr;
@@ -253,13 +255,15 @@ class_ancestry(X) ::= .						{ X = NULL; }
 class_ancestry(X) ::= COLON dottable_id(A).	{ X = A; /*X-overwrites-A*/ }
 
 %type class_flags{ClassFlagsBlock}
-class_flags(X) ::= .										{ X.Flags = 0; X.Replaces = NULL; X.Version = {0,0}; }
-class_flags(X) ::= class_flags(A) ABSTRACT.					{ X.Flags = A.Flags | ZCC_Abstract; X.Replaces = A.Replaces; }
-class_flags(X) ::= class_flags(A) NATIVE.					{ X.Flags = A.Flags | ZCC_Native; X.Replaces = A.Replaces; }
-class_flags(X) ::= class_flags(A) UI.						{ X.Flags = A.Flags | ZCC_UIFlag; X.Replaces = A.Replaces; }
-class_flags(X) ::= class_flags(A) PLAY.						{ X.Flags = A.Flags | ZCC_Play; X.Replaces = A.Replaces; }
-class_flags(X) ::= class_flags(A) REPLACES dottable_id(B).	{ X.Flags = A.Flags; X.Replaces = B; }
-class_flags(X) ::= class_flags(A) VERSION LPAREN STRCONST(C) RPAREN.	{ X.Flags = A.Flags | ZCC_Version; X.Replaces = A.Replaces; X.Version = C.String->GetChars(); }
+class_flags(X) ::= .										{ X.Flags = 0; X.Replaces = NULL; X.Version = {0,0}; X.Sealed = NULL; }
+class_flags(X) ::= class_flags(A) ABSTRACT.					{ X.Flags = A.Flags | ZCC_Abstract; X.Replaces = A.Replaces; X.Version = A.Version; X.Sealed = A.Sealed; }
+class_flags(X) ::= class_flags(A) FINAL.					{ X.Flags = A.Flags | ZCC_Final; X.Replaces = A.Replaces; X.Version = A.Version; X.Sealed =  A.Sealed;}
+class_flags(X) ::= class_flags(A) NATIVE.					{ X.Flags = A.Flags | ZCC_Native; X.Replaces = A.Replaces; X.Version = A.Version; X.Sealed =  A.Sealed; }
+class_flags(X) ::= class_flags(A) UI.						{ X.Flags = A.Flags | ZCC_UIFlag; X.Replaces = A.Replaces; X.Version = A.Version; X.Sealed =  A.Sealed; }
+class_flags(X) ::= class_flags(A) PLAY.						{ X.Flags = A.Flags | ZCC_Play; X.Replaces = A.Replaces; X.Version = A.Version; X.Sealed =  A.Sealed; }
+class_flags(X) ::= class_flags(A) REPLACES dottable_id(B).	{ X.Flags = A.Flags; X.Replaces = B; X.Version = A.Version; X.Sealed = A.Sealed; }
+class_flags(X) ::= class_flags(A) VERSION LPAREN STRCONST(C) RPAREN.	{ X.Flags = A.Flags | ZCC_Version; X.Replaces = A.Replaces; X.Version = C.String->GetChars(); X.Sealed =  A.Sealed; }
+class_flags(X) ::= class_flags(A) SEALED LPAREN states_opt(B) RPAREN.		{ X.Flags = A.Flags | ZCC_Sealed; X.Replaces = A.Replaces; X.Version = A.Version; X.Sealed = B; }
 
 /*----- Dottable Identifier -----*/
 // This can be either a single identifier or two identifiers connected by a .

src/common/scripting/frontend/zcc_compile.cpp

@@ -792,8 +792,14 @@ void ZCCCompiler::CreateClassTypes()
 			PClass *parent;
 			auto ParentName = c->cls->ParentName;
 
-			if (ParentName != nullptr && ParentName->SiblingNext == ParentName) parent = PClass::FindClass(ParentName->Id);
-			else if (ParentName == nullptr) parent = RUNTIME_CLASS(DObject);
+			if (ParentName != nullptr && ParentName->SiblingNext == ParentName)
+			{
+				parent = PClass::FindClass(ParentName->Id);
+			}
+			else if (ParentName == nullptr)
+			{
+				parent = RUNTIME_CLASS(DObject);
+			}
 			else
 			{
 				// The parent is a dotted name which the type system currently does not handle.
@@ -813,6 +819,15 @@ void ZCCCompiler::CreateClassTypes()
 
 			if (parent != nullptr && (parent->VMType != nullptr || c->NodeName() == NAME_Object))
 			{
+				if(parent->bFinal)
+				{
+					Error(c->cls, "Class '%s' cannot extend final class '%s'", FName(c->NodeName()).GetChars(), parent->TypeName.GetChars());
+				}
+				else if(parent->bSealed && !parent->SealedRestriction.Contains(c->NodeName()))
+				{
+					Error(c->cls, "Class '%s' cannot extend sealed class '%s'", FName(c->NodeName()).GetChars(), parent->TypeName.GetChars());
+				}
+
 				// The parent exists, we may create a type for this class
 				if (c->cls->Flags & ZCC_Native)
 				{
@@ -874,6 +889,25 @@ void ZCCCompiler::CreateClassTypes()
 				{
 					c->Type()->mVersion = c->cls->Version;
 				}
+				
+
+				if (c->cls->Flags & ZCC_Final)
+				{
+					c->ClassType()->bFinal = true;
+				}
+
+				if (c->cls->Flags & ZCC_Sealed)
+				{
+					PClass * ccls = c->ClassType();
+					ccls->bSealed = true;
+					ZCC_Identifier * it = c->cls->Sealed;
+					if(it) do
+					{
+						ccls->SealedRestriction.Push(FName(it->Id));
+						it = (ZCC_Identifier*) it->SiblingNext;
+					}
+					while(it != c->cls->Sealed);
+				}
 				// 
 				if (mVersion >= MakeVersion(2, 4, 0))
 				{

src/common/scripting/frontend/zcc_parser.cpp

@@ -232,6 +232,7 @@ static void InitTokenMap()
 	TOKENDEF (TK_Out,			ZCC_OUT);
 	TOKENDEF (TK_Super,			ZCC_SUPER);
 	TOKENDEF (TK_Null,			ZCC_NULLPTR);
+	TOKENDEF (TK_Sealed,		ZCC_SEALED);
 	TOKENDEF ('~',				ZCC_TILDE);
 	TOKENDEF ('!',				ZCC_BANG);
 	TOKENDEF (TK_SizeOf,		ZCC_SIZEOF);

src/common/scripting/frontend/zcc_parser.h

@@ -64,6 +64,7 @@ enum
 	ZCC_VirtualScope	= 1 << 20,
 	ZCC_Version			= 1 << 21,
 	ZCC_Internal		= 1 << 22,
+	ZCC_Sealed			= 1 << 23,
 };
 
 // Function parameter modifiers
@@ -251,6 +252,7 @@ struct ZCC_Class : ZCC_Struct
 {
 	ZCC_Identifier *ParentName;
 	ZCC_Identifier *Replaces;
+	ZCC_Identifier *Sealed;
 
 	PClass *CType() { return static_cast<PClassType *>(Type)->Descriptor; }
 };