From 2ac65bf03cd1cd57419d957dc352827eff2e8efd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michael=20Vo=C5=99=C3=AD=C5=A1ek?= <mvorisek@mvorisek.cz>
Date: Thu, 7 Jul 2022 12:49:09 +0200
Subject: [PATCH] Fix GH-8924 str_split of empty string must return empty array

Co-authored-by: Christoph M. Becker <cmbecker69@gmx.de>
---
 ext/standard/string.c                              |  6 +++++-
 ext/standard/tests/strings/str_split_basic.phpt    | 14 ++++++++++++--
 .../tests/strings/str_split_variation3.phpt        |  4 +---
 .../tests/strings/str_split_variation4.phpt        |  4 +---
 .../tests/strings/str_split_variation5.phpt        |  8 ++------
 5 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/ext/standard/string.c b/ext/standard/string.c
index 699bccbae6af9..bf46c90fd18b9 100644
--- a/ext/standard/string.c
+++ b/ext/standard/string.c
@@ -5882,7 +5882,11 @@ PHP_FUNCTION(str_split)
 		RETURN_THROWS();
 	}
 
-	if (0 == ZSTR_LEN(str) || (size_t)split_length >= ZSTR_LEN(str)) {
+	if ((size_t)split_length >= ZSTR_LEN(str)) {
+		if (0 == ZSTR_LEN(str)) {
+			RETURN_EMPTY_ARRAY();
+		}
+
 		array_init_size(return_value, 1);
 		add_next_index_stringl(return_value, ZSTR_VAL(str), ZSTR_LEN(str));
 		return;
diff --git a/ext/standard/tests/strings/str_split_basic.phpt b/ext/standard/tests/strings/str_split_basic.phpt
index ce0f1004c7a05..86bf288464229 100644
--- a/ext/standard/tests/strings/str_split_basic.phpt
+++ b/ext/standard/tests/strings/str_split_basic.phpt
@@ -16,7 +16,11 @@ var_dump( str_split($str,$split_length) );
 echo "-- With split_length as default argument --\n";
 var_dump( str_split($str) );
 
-echo "Done"
+echo "-- Empty string must always return empty array --\n";
+var_dump( str_split('') );
+var_dump( str_split('', 1) );
+var_dump( str_split('', 100) );
+
 ?>
 --EXPECT--
 *** Testing str_split() : basic functionality ***
@@ -80,4 +84,10 @@ array(22) {
   [21]=>
   string(1) "e"
 }
-Done
+-- Empty string must always return empty array --
+array(0) {
+}
+array(0) {
+}
+array(0) {
+}
diff --git a/ext/standard/tests/strings/str_split_variation3.phpt b/ext/standard/tests/strings/str_split_variation3.phpt
index 7003d62eaa1fb..53a78244c56a5 100644
--- a/ext/standard/tests/strings/str_split_variation3.phpt
+++ b/ext/standard/tests/strings/str_split_variation3.phpt
@@ -39,9 +39,7 @@ echo "Done"
 --EXPECTF--
 *** Testing str_split() : double quoted strings for 'str' ***
 -- Iteration 1 --
-array(1) {
-  [0]=>
-  string(0) ""
+array(0) {
 }
 -- Iteration 2 --
 array(1) {
diff --git a/ext/standard/tests/strings/str_split_variation4.phpt b/ext/standard/tests/strings/str_split_variation4.phpt
index b10fd0c7d9e3c..c3c71bd0c52e7 100644
--- a/ext/standard/tests/strings/str_split_variation4.phpt
+++ b/ext/standard/tests/strings/str_split_variation4.phpt
@@ -38,9 +38,7 @@ echo "Done"
 --EXPECT--
 *** Testing str_split() : single quoted strings for 'str' ***
 -- Iteration 1 --
-array(1) {
-  [0]=>
-  string(0) ""
+array(0) {
 }
 -- Iteration 2 --
 array(1) {
diff --git a/ext/standard/tests/strings/str_split_variation5.phpt b/ext/standard/tests/strings/str_split_variation5.phpt
index 02c7d61eb13b1..656bcad7d1ad5 100644
--- a/ext/standard/tests/strings/str_split_variation5.phpt
+++ b/ext/standard/tests/strings/str_split_variation5.phpt
@@ -81,14 +81,10 @@ echo "Done"
 --EXPECT--
 *** Testing str_split() : heredoc strings as 'str' argument ***
 -- Iteration 1 --
-array(1) {
-  [0]=>
-  string(0) ""
+array(0) {
 }
 -- Iteration 2 --
-array(1) {
-  [0]=>
-  string(0) ""
+array(0) {
 }
 -- Iteration 3 --
 array(1) {