Handle error instead of throwing an exception when TypeExprKinds cannot be resolved.

Author: Napalys

javascript/extractor/src/com/semmle/js/extractor/ASTExtractor.java

@@ -405,20 +405,31 @@ private Label visitAll(
       return res;
     }
 
+    /**
+     * Handles cases where an expression or type expression kind cannot be determined.
+     */
+    private void handleUnknownKind(Node nd, String nodeName) {
+        String message = "Cannot determine kind for " + nodeName + ": " + nd.getClass().getSimpleName();
+        additionalErrors.add(new ParseError(message, nd.getLoc().getStart()));
+    }
+
     @Override
     public Label visit(Expression nd, Context c) {
       int kind =
           c.isInsideType()
               ? TypeExprKinds.getTypeExprKind(nd, c.idcontext)
               : ExprKinds.getExprKind(nd, c.idcontext);
+      if(kind == -1) handleUnknownKind(nd, "expression");
       Label lbl = visit(nd, kind, c);
       emitStaticType(nd, lbl);
       return lbl;
     }
 
     @Override
     public Label visit(TypeExpression nd, Context c) {
-      Label lbl = visit(nd, TypeExprKinds.getTypeExprKind(nd, c.idcontext), c);
+      int kind = TypeExprKinds.getTypeExprKind(nd, c.idcontext);
+      if(kind == -1) handleUnknownKind(nd, "type expression");
+      Label lbl = visit(nd, kind, c);
       emitStaticType(nd, lbl);
       return lbl;
     }

javascript/extractor/src/com/semmle/js/extractor/TypeExprKinds.java

@@ -34,6 +34,7 @@
 import com.semmle.util.exception.CatastrophicError;
 
 public class TypeExprKinds {
+  private static final int invalidTypeExpr = -1;
   private static final int simpleTypeAccess = 0;
   private static final int typeDecl = 1;
   private static final int keywordTypeExpr = 2;
@@ -273,8 +274,9 @@ public Integer visit(TemplateElement nd, Void c) {
               }
             },
             null);
-    if (kind == null)
-      throw new CatastrophicError("Unsupported type expression kind: " + type.getClass());
+    if (kind == null) {
+      return invalidTypeExpr;
+    }
     return kind;
   }
 }

javascript/extractor/tests/ts/input/invalidExtends.ts

@@ -0,0 +1,5 @@
+interface Invalid extends (foo.bar), (foo).bar, foo[bar], foo?.bar, foo!.bar, foo(), import.meta {}
+interface Employee extends Person {
+    position: string;
+    salary: number;
+}