Merge branch '5.4' into 6.4

* 5.4:
  [Process] Properly deal with not-found executables on Windows
  [Process] Fix handling empty path found in the PATH env var with ExecutableFinder

Author: nicolas-grekas

src/Symfony/Component/Process/ExecutableFinder.php

@@ -62,6 +62,9 @@ public function find(string $name, ?string $default = null, array $extraDirs = [
         }
         foreach ($suffixes as $suffix) {
             foreach ($dirs as $dir) {
+                if ('' === $dir) {
+                    $dir = '.';
+                }
                 if (@is_file($file = $dir.\DIRECTORY_SEPARATOR.$name.$suffix) && ('\\' === \DIRECTORY_SEPARATOR || @is_executable($file))) {
                     return $file;
                 }
@@ -72,8 +75,14 @@ public function find(string $name, ?string $default = null, array $extraDirs = [
             }
         }
 
-        $command = '\\' === \DIRECTORY_SEPARATOR ? 'where' : 'command -v --';
-        if (\function_exists('exec') && ($executablePath = strtok(@exec($command.' '.escapeshellarg($name)), \PHP_EOL)) && @is_executable($executablePath)) {
+        if (!\function_exists('exec') || \strlen($name) !== strcspn($name, '/'.\DIRECTORY_SEPARATOR)) {
+            return $default;
+        }
+
+        $command = '\\' === \DIRECTORY_SEPARATOR ? 'where %s 2> NUL' : 'command -v -- %s';
+        $execResult = exec(\sprintf($command, escapeshellarg($name)));
+
+        if (($executablePath = substr($execResult, 0, strpos($execResult, \PHP_EOL) ?: null)) && @is_executable($executablePath)) {
             return $executablePath;
         }
 

src/Symfony/Component/Process/PhpExecutableFinder.php

@@ -33,12 +33,16 @@ public function find(bool $includeArgs = true): string|false
     {
         if ($php = getenv('PHP_BINARY')) {
             if (!is_executable($php)) {
-                $command = '\\' === \DIRECTORY_SEPARATOR ? 'where' : 'command -v --';
-                if (\function_exists('exec') && $php = strtok(exec($command.' '.escapeshellarg($php)), \PHP_EOL)) {
-                    if (!is_executable($php)) {
-                        return false;
-                    }
-                } else {
+                if (!\function_exists('exec') || \strlen($php) !== strcspn($php, '/'.\DIRECTORY_SEPARATOR)) {
+                    return false;
+                }
+
+                $command = '\\' === \DIRECTORY_SEPARATOR ? 'where %s 2> NUL' : 'command -v -- %s';
+                $execResult = exec(\sprintf($command, escapeshellarg($php)));
+                if (!$php = substr($execResult, 0, strpos($execResult, \PHP_EOL) ?: null)) {
+                    return false;
+                }
+                if (!is_executable($php)) {
                     return false;
                 }
             }

src/Symfony/Component/Process/Tests/ExecutableFinderTest.php

@@ -111,6 +111,9 @@ public function testFindWithOpenBaseDir()
         }
     }
 
+    /**
+     * @runInSeparateProcess
+     */
     public function testFindBatchExecutableOnWindows()
     {
         if (\ini_get('open_basedir')) {
@@ -138,6 +141,24 @@ public function testFindBatchExecutableOnWindows()
         $this->assertSamePath($target.'.BAT', $result);
     }
 
+    /**
+     * @runInSeparateProcess
+     */
+    public function testEmptyDirInPath()
+    {
+        putenv(sprintf('PATH=%s:', \dirname(\PHP_BINARY)));
+
+        touch('executable');
+        chmod('executable', 0700);
+
+        $finder = new ExecutableFinder();
+        $result = $finder->find('executable');
+
+        $this->assertSame('./executable', $result);
+
+        unlink('executable');
+    }
+
     private function assertSamePath($expected, $tested)
     {
         if ('\\' === \DIRECTORY_SEPARATOR) {