Handle infinite opt terms after missing case predicate

Author: kddnewton

src/yarp.c

@@ -11703,11 +11703,12 @@ parse_expression_prefix(yp_parser_t *parser, yp_binding_power_t binding_power) {
             yp_token_t case_keyword = parser->previous;
             yp_node_t *predicate = NULL;
 
-            if (
-                accept2(parser, YP_TOKEN_NEWLINE, YP_TOKEN_SEMICOLON) ||
-                match3(parser, YP_TOKEN_KEYWORD_WHEN, YP_TOKEN_KEYWORD_IN, YP_TOKEN_KEYWORD_END) ||
-                !token_begins_expression_p(parser->current.type)
-            ) {
+            if (accept2(parser, YP_TOKEN_NEWLINE, YP_TOKEN_SEMICOLON)) {
+                while (accept2(parser, YP_TOKEN_NEWLINE, YP_TOKEN_SEMICOLON));
+                predicate = NULL;
+            } else if (match3(parser, YP_TOKEN_KEYWORD_WHEN, YP_TOKEN_KEYWORD_IN, YP_TOKEN_KEYWORD_END)) {
+                predicate = NULL;
+             } else if (!token_begins_expression_p(parser->current.type)) {
                 predicate = NULL;
             } else {
                 predicate = parse_expression(parser, YP_BINDING_POWER_COMPOSITION, YP_ERR_CASE_EXPRESSION_AFTER_CASE);

test/yarp/fixtures/case.txt

@@ -28,3 +28,5 @@ case type;
   ;when :b;
   ;  else;
    end
+
+case ;;;;;;;; when 1; end