Fix GH-18120: Honor FILE_SKIP_EMPTY_LINES even when FILE_IGNORE_NEW_LINES is not set

Author: alexandre-daubois

UPGRADING

@@ -429,6 +429,11 @@ PHP 8.5 UPGRADE NOTES
   . socket_set_option with multicast context throws a ValueError
     when the created socket is not of AF_INET/AF_INET6 family.
 
+- Standard:
+  . file() now correctly honors the FILE_SKIP_EMPTY_LINES flag even when
+    FILE_IGNORE_NEW_LINES is not set. Previously, FILE_SKIP_EMPTY_LINES
+    only worked when combined with FILE_IGNORE_NEW_LINES. See GH-18120.
+
 - Tidy:
   . tidy::__construct/parseFile/parseString now throws a ValueError
     if the configuration contains an invalid or set a read-only

ext/standard/file.c

@@ -640,6 +640,16 @@ PHP_FUNCTION(file)
 			do {
 				p++;
 parse_eol:
+				if (skip_blank_lines) {
+					int windows_eol = 0;
+					if (p != ZSTR_VAL(target_buf) && eol_marker == '\n' && *(p - 1) == '\r') {
+						windows_eol++;
+					}
+					if (p-s-windows_eol == 1) {
+						s = p;
+						continue;
+					}
+				}
 				add_index_stringl(return_value, i++, s, p-s);
 				s = p;
 			} while ((p = memchr(p, eol_marker, (e-p))));

ext/standard/tests/file/file_skip_empty_lines.phpt

@@ -0,0 +1,103 @@
+--TEST--
+Test file() function with FILE_SKIP_EMPTY_LINES flag
+--FILE--
+<?php
+$test_file = __DIR__ . "/file_skip_empty_lines.tmp";
+
+$test_data = "First\n\nSecond\n\n\nThird\n";
+file_put_contents($test_file, $test_data);
+
+$lines = file($test_file, FILE_SKIP_EMPTY_LINES);
+var_dump($lines);
+
+$lines = file($test_file, FILE_SKIP_EMPTY_LINES | FILE_IGNORE_NEW_LINES);
+var_dump($lines);
+
+$lines = file($test_file, FILE_IGNORE_NEW_LINES);
+var_dump($lines);
+
+$lines = file($test_file);
+var_dump($lines);
+
+$test_data_win = "First\r\n\r\nSecond\r\n";
+file_put_contents($test_file, $test_data_win);
+
+$lines = file($test_file, FILE_SKIP_EMPTY_LINES);
+var_dump($lines);
+
+$lines = file($test_file, FILE_SKIP_EMPTY_LINES | FILE_IGNORE_NEW_LINES);
+var_dump($lines);
+
+unlink($test_file);
+?>
+--EXPECT--
+array(3) {
+  [0]=>
+  string(6) "First
+"
+  [1]=>
+  string(7) "Second
+"
+  [2]=>
+  string(6) "Third
+"
+}
+array(3) {
+  [0]=>
+  string(5) "First"
+  [1]=>
+  string(6) "Second"
+  [2]=>
+  string(5) "Third"
+}
+array(6) {
+  [0]=>
+  string(5) "First"
+  [1]=>
+  string(0) ""
+  [2]=>
+  string(6) "Second"
+  [3]=>
+  string(0) ""
+  [4]=>
+  string(0) ""
+  [5]=>
+  string(5) "Third"
+}
+array(6) {
+  [0]=>
+  string(6) "First
+"
+  [1]=>
+  string(1) "
+"
+  [2]=>
+  string(7) "Second
+"
+  [3]=>
+  string(1) "
+"
+  [4]=>
+  string(1) "
+"
+  [5]=>
+  string(6) "Third
+"
+}
+array(3) {
+  [0]=>
+  string(7) "First
+"
+  [1]=>
+  string(2) "
+"
+  [2]=>
+  string(8) "Second
+"
+}
+array(2) {
+  [0]=>
+  string(5) "First"
+  [1]=>
+  string(6) "Second"
+}

ext/standard/tests/file/file_variation.phpt

@@ -106,20 +106,14 @@ array(5) {
   [4]=>
   string(5) " data"
 }
-array(5) {
+array(3) {
   [0]=>
   string(4) "Gar
 "
   [1]=>
-  string(1) "
-"
-  [2]=>
   string(6) "bage 
 "
-  [3]=>
-  string(1) "
-"
-  [4]=>
+  [2]=>
   string(5) " data"
 }
 *** Testing with variation in use_include_path argument ***

ext/standard/tests/file/file_variation7.phpt

@@ -62,20 +62,17 @@ array(5) {
 }
 
 file() with FILE_SKIP_EMPTY_LINES:
-array(5) {
+array(4) {
   [0]=>
   string(7) "Line 1
 "
   [1]=>
-  string(1) "
-"
-  [2]=>
   string(2) " 
 "
-  [3]=>
+  [2]=>
   string(3) "  
 "
-  [4]=>
+  [3]=>
   string(7) "\Line 3"
 }