From 2ccaaaa1017fa411134648bbaa6fa8f8b875e16d Mon Sep 17 00:00:00 2001
From: Benoit Daloze <eregontp@gmail.com>
Date: Sat, 29 Jul 2023 16:13:52 +0200
Subject: [PATCH] [ruby/yarp] Add simpler exported unescape function to
 librubyparser

* Moves logic from the C extension to librubyparser which can be shared with the Fiddle backend.

https://github.com/ruby/yarp/commit/aa48d5e444
---
 yarp/extension.c | 28 +++++++---------------------
 yarp/unescape.c  | 21 ++++++++++++++++++++-
 yarp/unescape.h  |  4 ++++
 3 files changed, 31 insertions(+), 22 deletions(-)

diff --git a/yarp/extension.c b/yarp/extension.c
index 7ede50bb0f..36e9941d64 100644
--- a/yarp/extension.c
+++ b/yarp/extension.c
@@ -529,30 +529,16 @@ named_captures(VALUE self, VALUE source) {
 // version.
 static VALUE
 unescape(VALUE source, yp_unescape_type_t unescape_type) {
-    yp_string_t string;
-    VALUE result;
+    yp_string_t result;
 
-    yp_list_t error_list;
-    yp_list_init(&error_list);
-
-    const char *start = RSTRING_PTR(source);
-    size_t length = RSTRING_LEN(source);
-
-    yp_parser_t parser;
-    yp_parser_init(&parser, start, length, "");
-
-    yp_unescape_manipulate_string(&parser, start, length, &string, unescape_type, &error_list);
-    if (yp_list_empty_p(&error_list)) {
-        result = rb_str_new(yp_string_source(&string), yp_string_length(&string));
+    if (yp_unescape_string(RSTRING_PTR(source), RSTRING_LEN(source), unescape_type, &result)) {
+        VALUE str = rb_str_new(yp_string_source(&result), yp_string_length(&result));
+        yp_string_free(&result);
+        return str;
     } else {
-        result = Qnil;
+        yp_string_free(&result);
+        return Qnil;
     }
-
-    yp_string_free(&string);
-    yp_list_free(&error_list);
-    yp_parser_free(&parser);
-
-    return result;
 }
 
 // Do not unescape anything in the given string. This is here to provide a
diff --git a/yarp/unescape.c b/yarp/unescape.c
index 296caf01aa..3f6e70216c 100644
--- a/yarp/unescape.c
+++ b/yarp/unescape.c
@@ -1,4 +1,4 @@
-#include "yarp/unescape.h"
+#include "yarp.h"
 
 /******************************************************************************/
 /* Character checks                                                           */
@@ -528,6 +528,25 @@ yp_unescape_manipulate_string(yp_parser_t *parser, const char *value, size_t len
     string->as.owned.length = dest_length + ((size_t) (end - cursor));
 }
 
+YP_EXPORTED_FUNCTION bool
+yp_unescape_string(const char *start, size_t length, yp_unescape_type_t unescape_type, yp_string_t *result) {
+    bool success;
+
+    yp_list_t error_list;
+    yp_list_init(&error_list);
+
+    yp_parser_t parser;
+    yp_parser_init(&parser, start, length, "");
+
+    yp_unescape_manipulate_string(&parser, start, length, result, unescape_type, &error_list);
+    success = yp_list_empty_p(&error_list);
+
+    yp_list_free(&error_list);
+    yp_parser_free(&parser);
+
+    return success;
+}
+
 // This function is similar to yp_unescape_manipulate_string, except it doesn't
 // actually perform any string manipulations. Instead, it calculates how long
 // the unescaped character is, and returns that value
diff --git a/yarp/unescape.h b/yarp/unescape.h
index 15e7cf2e17..b76ac9f7a4 100644
--- a/yarp/unescape.h
+++ b/yarp/unescape.h
@@ -33,6 +33,10 @@ typedef enum {
 // given unescape mode.
 YP_EXPORTED_FUNCTION void yp_unescape_manipulate_string(yp_parser_t *parser, const char *value, size_t length, yp_string_t *string, yp_unescape_type_t unescape_type, yp_list_t *error_list);
 
+// Accepts a source string and a type of unescaping and returns the unescaped version.
+// The caller must yp_string_free(result); after calling this function.
+YP_EXPORTED_FUNCTION bool yp_unescape_string(const char *start, size_t length, yp_unescape_type_t unescape_type, yp_string_t *result);
+
 YP_EXPORTED_FUNCTION size_t yp_unescape_calculate_difference(const char *value, const char *end, yp_unescape_type_t unescape_type, bool expect_single_codepoint, yp_list_t *error_list);
 
 #endif