Reverse sync from upstream

Author: kddnewton

src/prism.c

@@ -9653,7 +9653,8 @@ escape_read_warn(pm_parser_t *parser, uint8_t flags, uint8_t flag, const char *t
  */
 static void
 escape_read(pm_parser_t *parser, pm_buffer_t *buffer, pm_buffer_t *regular_expression_buffer, uint8_t flags) {
-    switch (peek(parser)) {
+    uint8_t peeked = peek(parser);
+    switch (peeked) {
         case '\\': {
             parser->current.end++;
             escape_write_byte(parser, buffer, regular_expression_buffer, flags, escape_byte('\\', flags));
@@ -9723,6 +9724,7 @@ escape_read(pm_parser_t *parser, pm_buffer_t *buffer, pm_buffer_t *regular_expre
                 }
             }
 
+            value = escape_byte(value, flags);
             escape_write_byte(parser, buffer, regular_expression_buffer, flags, value);
             return;
         }
@@ -10050,6 +10052,11 @@ escape_read(pm_parser_t *parser, pm_buffer_t *buffer, pm_buffer_t *regular_expre
             PRISM_FALLTHROUGH
         }
         default: {
+            if ((flags & (PM_ESCAPE_FLAG_CONTROL | PM_ESCAPE_FLAG_META)) && !char_is_ascii_printable(peeked)) {
+                size_t width = parser->encoding->char_width(parser->current.end, parser->end - parser->current.end);
+                pm_parser_err(parser, parser->current.start, parser->current.end + width, PM_ERR_ESCAPE_INVALID_META);
+                return;
+            }
             if (parser->current.end < parser->end) {
                 escape_write_escape_encoded(parser, buffer, regular_expression_buffer, flags);
             } else {