From 23d960f5e5f1b9c9db1698db05cbdcbcbf22d659 Mon Sep 17 00:00:00 2001
From: Lars Reimann <mail@larsreimann.com>
Date: Thu, 12 Oct 2023 19:45:24 +0200
Subject: [PATCH] feat: error if call receiver is class without constructor

---
 src/language/validation/types.ts                   |  7 ++++++-
 .../main.sdstest                                   | 14 ++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 tests/resources/validation/types/checking/called class must have constructor/main.sdstest

diff --git a/src/language/validation/types.ts b/src/language/validation/types.ts
index 3170c0260..b44007ddb 100644
--- a/src/language/validation/types.ts
+++ b/src/language/validation/types.ts
@@ -1,7 +1,7 @@
 import { getContainerOfType, ValidationAcceptor } from 'langium';
 import {
     isSdsAnnotation,
-    isSdsCallable,
+    isSdsCallable, isSdsClass,
     isSdsLambda, isSdsMemberAccess, isSdsPipeline, isSdsReference, isSdsSchema,
     SdsAttribute,
     SdsCall,
@@ -46,6 +46,11 @@ export const callReceiverMustBeCallable = (services: SafeDsServices) => {
                 node: node.receiver,
                 code: CODE_TYPE_CALLABLE_RECEIVER,
             });
+        } else if (isSdsClass(callable) && !callable.parameterList) {
+            accept('error', "Cannot instantiate a class that has no constructor.", {
+                node: node.receiver,
+                code: CODE_TYPE_CALLABLE_RECEIVER,
+            });
         }
     };
 };
diff --git a/tests/resources/validation/types/checking/called class must have constructor/main.sdstest b/tests/resources/validation/types/checking/called class must have constructor/main.sdstest
new file mode 100644
index 000000000..d42292ebe
--- /dev/null
+++ b/tests/resources/validation/types/checking/called class must have constructor/main.sdstest	
@@ -0,0 +1,14 @@
+package tests.validation.types.checking.calledClassMustHaveConstructor
+
+class A
+
+class B()
+
+pipeline test {
+
+    // $TEST$ error "Cannot instantiate a class that has no constructor."
+    val a = »A«();
+
+    // $TEST$ no error "Cannot instantiate a class that has no constructor."
+    val b = »B«();
+}