From c9c5f575ca5200d28ab77829c6c33c7fbad0e84e Mon Sep 17 00:00:00 2001
From: Earlopain <14981592+Earlopain@users.noreply.github.com>
Date: Mon, 12 Oct 2026 09:23:31 +0200
Subject: [PATCH] Initialize `filepath` option to the empty string

Same as `current_string`, set it to be empty.
Similarly, when populating user-provided options, we need to check the lengh, same as for `encoding`.

Closes https://github.com/ruby/prism/issues/4249
---
 src/prism.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/prism.c b/src/prism.c
index d436fbd609..9bf07856cb 100644
--- a/src/prism.c
+++ b/src/prism.c
@@ -22992,7 +22992,7 @@ pm_parser_init(pm_arena_t *arena, pm_parser_t *parser, const uint8_t *source, si
         .encoding_changed_callback = NULL,
         .encoding_comment_start = source,
         .lex_callback = { 0 },
-        .filepath = { 0 },
+        .filepath = PM_STRING_EMPTY,
         .constant_pool = { 0 },
         .line_offsets = { 0 },
         .integer = { 0 },
@@ -23040,7 +23040,9 @@ pm_parser_init(pm_arena_t *arena, pm_parser_t *parser, const uint8_t *source, si
     // If options were provided to this parse, establish them here.
     if (options != NULL) {
         // filepath option
-        parser->filepath = options->filepath;
+        if (pm_string_length(&options->filepath) > 0) {
+            parser->filepath = options->filepath;
+        }
 
         // line option
         parser->start_line = options->line;