minor #13600 [Process] added a deprecation notice (fabpot)

This PR was merged into the 2.7 branch.

Discussion
----------

[Process] added a deprecation notice

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | yes
| Tests pass?   | yes
| Fixed tickets | #12703, #12725
| License       | MIT
| Doc PR        | n/a

Commits
-------

a901ca2 [Process] added a deprecation notice

src/Symfony/Component/Process/Process.php

@@ -1108,11 +1108,13 @@ class Process
      *
      * This content will be passed to the underlying process standard input.
      *
-     * @param string|null $input The content
+     * @param mixed $input The content
      *
      * @return self The current Process instance
      *
      * @throws LogicException In case the process is running
+     *
+     * Passing an object as an input is deprecated since version 2.5 and will be removed in 3.0.
      */
     public function setInput($input)
     {

src/Symfony/Component/Process/ProcessBuilder.php

@@ -167,11 +167,13 @@ class ProcessBuilder
     /**
      * Sets the input of the process.
      *
-     * @param string|null $input The input as a string
+     * @param mixed $input The input as a string
      *
      * @return ProcessBuilder
      *
      * @throws InvalidArgumentException In case the argument is invalid
+     *
+     * Passing an object as an input is deprecated since version 2.5 and will be removed in 3.0.
      */
     public function setInput($input)
     {

src/Symfony/Component/Process/ProcessUtils.php

@@ -83,6 +83,8 @@ class ProcessUtils
      * @return string The validated input
      *
      * @throws InvalidArgumentException In case the input is not valid
+     *
+     * Passing an object as an input is deprecated since version 2.5 and will be removed in 3.0.
      */
     public static function validateInput($caller, $input)
     {
@@ -95,6 +97,8 @@ class ProcessUtils
             }
             // deprecated as of Symfony 2.5, to be removed in 3.0
             if (is_object($input) && method_exists($input, '__toString')) {
+                trigger_error('Passing an object as an input is deprecated since version 2.5 and will be removed in 3.0.', E_USER_DEPRECATED);
+
                 return (string) $input;
             }
 

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

@@ -229,7 +229,24 @@ abstract class AbstractProcessTest extends \PHPUnit_Framework_TestCase
             array(null, null),
             array('24.5', 24.5),
             array('input data', 'input data'),
-            // to maintain BC, supposed to be removed in 3.0
+        );
+    }
+
+    /**
+     * @dataProvider provideLegacyInputValues
+     */
+    public function testLegacyValidInput($expected, $value)
+    {
+        $this->iniSet('error_reporting', -1 & ~E_USER_DEPRECATED);
+
+        $process = $this->getProcess('php -v');
+        $process->setInput($value);
+        $this->assertSame($expected, $process->getInput());
+    }
+
+    public function provideLegacyInputValues()
+    {
+        return array(
             array('stringifiable', new Stringifiable()),
         );
     }