[error] Reject instantiation of abstract and static classes.

Fix #200

Author: pfusik

Sema.fu

@@ -1657,6 +1657,16 @@ public class FuSema
 			if (call.Method.Name == "string")
 				return this.Host.Program.System.StringStorageType;
 			if (this.Host.Program.TryLookup(call.Method.Name, true) is FuClass! klass2) {
+				switch (klass2.CallType) {
+				case FuCallType.Static:
+					ReportError(expr, "Cannot instantiate static class");
+					break;
+				case FuCallType.Abstract:
+					ReportError(expr, "Cannot instantiate abstract class");
+					break;
+				default:
+					break;
+				}
 				call.Method.Symbol = klass2; // for vscode goto
 				return new FuStorageType { Class = klass2 };
 			}

libfut.cpp

@@ -6239,6 +6239,16 @@ std::shared_ptr<FuType> FuSema::toBaseType(FuExpr * expr, FuToken ptrModifier, b
 		if (call->method->name == "string")
 			return this->host->program->system->stringStorageType;
 		if (FuClass *klass2 = dynamic_cast<FuClass *>(this->host->program->tryLookup(call->method->name, true).get())) {
+			switch (klass2->callType) {
+			case FuCallType::static_:
+				reportError(expr, "Cannot instantiate static class");
+				break;
+			case FuCallType::abstract:
+				reportError(expr, "Cannot instantiate abstract class");
+				break;
+			default:
+				break;
+			}
 			call->method->symbol = klass2;
 			std::shared_ptr<FuStorageType> futemp0 = std::make_shared<FuStorageType>();
 			futemp0->class_ = klass2;

libfut.cs

@@ -6326,6 +6326,16 @@ FuType ToBaseType(FuExpr expr, FuToken ptrModifier, bool nullable)
 				if (call.Method.Name == "string")
 					return this.Host.Program.System.StringStorageType;
 				if (this.Host.Program.TryLookup(call.Method.Name, true) is FuClass klass2) {
+					switch (klass2.CallType) {
+					case FuCallType.Static:
+						ReportError(expr, "Cannot instantiate static class");
+						break;
+					case FuCallType.Abstract:
+						ReportError(expr, "Cannot instantiate abstract class");
+						break;
+					default:
+						break;
+					}
 					call.Method.Symbol = klass2;
 					return new FuStorageType { Class = klass2 };
 				}

libfut.js

@@ -6703,6 +6703,16 @@ export class FuSema
 				return this.#host.program.system.stringStorageType;
 			let klass2;
 			if ((klass2 = this.#host.program.tryLookup(call.method.name, true)) instanceof FuClass) {
+				switch (klass2.callType) {
+				case FuCallType.STATIC:
+					this.#reportError(expr, "Cannot instantiate static class");
+					break;
+				case FuCallType.ABSTRACT:
+					this.#reportError(expr, "Cannot instantiate abstract class");
+					break;
+				default:
+					break;
+				}
 				call.method.symbol = klass2;
 				return Object.assign(new FuStorageType(), { class: klass2 });
 			}

test/error/ClassAbstractInstance.fu

@@ -0,0 +1,10 @@
+public abstract class Test
+{
+	public static bool Run()
+	{
+		Test() o; //ERROR: Cannot instantiate abstract class
+		Test()[3] a; //ERROR: Cannot instantiate abstract class
+		Test# p = new Test(); //ERROR: Cannot instantiate abstract class
+		return true;
+	}
+}

test/error/ClassStaticInstance.fu

@@ -0,0 +1,10 @@
+public static class Test
+{
+	public static bool Run()
+	{
+		Test() o; //ERROR: Cannot instantiate static class
+		Test()[3] a; //ERROR: Cannot instantiate static class
+		Test# p = new Test(); //ERROR: Cannot instantiate static class
+		return true;
+	}
+}

test/error/OpIndexObject.fu

@@ -1,4 +1,4 @@
-public static class Test
+public class Test
 {
 	public static bool Run()
 	{