Empty interfaces break the parser

src/parser/Parser.ts

@@ -489,6 +489,11 @@ export class Parser {
         let body = [] as Statement[];
         while (this.checkAny(TokenKind.Comment, TokenKind.Identifier, TokenKind.At, ...AllowedProperties)) {
             try {
+                //break out of this loop if we encountered the `EndInterface` token not followed by `as`
+                if (this.check(TokenKind.EndInterface) && !this.checkNext(TokenKind.As)) {
+                    break;
+                }
+
                 let decl: Statement;
 
                 //collect leading annotations
@@ -528,10 +533,6 @@ export class Parser {
 
             //ensure statement separator
             this.consumeStatementSeparators();
-            //break out of this loop if we encountered the `EndInterface` token not followed by `as`
-            if (this.check(TokenKind.EndInterface) && !this.checkNext(TokenKind.As)) {
-                break;
-            }
         }
 
         //consume the final `end interface` token

src/parser/tests/statement/InterfaceStatement.spec.ts

@@ -96,4 +96,13 @@ describe('InterfaceStatement', () => {
             end interface
         `, undefined, undefined, undefined, true);
     });
+
+    it('supports empty interfaces', () => {
+        const file = program.setFile('source/main.bs', `
+           interface SomeInterface
+           end interface
+        `);
+        program.validate();
+        expectZeroDiagnostics(file);
+    });
 });