From 2c0815d04e0234a4a10b2232fa5911451b256ddd Mon Sep 17 00:00:00 2001
From: Thomas Calvet <calvet.thomas@gmail.com>
Date: Fri, 30 Jun 2023 18:17:14 +0200
Subject: [PATCH] [DependencyInjection] Fix autocasting null env values to
 empty string

---
 .../Component/DependencyInjection/Container.php  | 10 +++++++++-
 .../DependencyInjection/EnvVarProcessor.php      | 10 ++++++++++
 .../Tests/EnvVarProcessorTest.php                | 16 +++++++++++++++-
 3 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/src/Symfony/Component/DependencyInjection/Container.php b/src/Symfony/Component/DependencyInjection/Container.php
index 838756d47edba..235b76ef44fd1 100644
--- a/src/Symfony/Component/DependencyInjection/Container.php
+++ b/src/Symfony/Component/DependencyInjection/Container.php
@@ -390,7 +390,15 @@ protected function getEnv(string $name)
             $prefix = 'string';
             $localName = $name;
         }
-        $processor = $processors->has($prefix) ? $processors->get($prefix) : new EnvVarProcessor($this);
+
+        if ($processors->has($prefix)) {
+            $processor = $processors->get($prefix);
+        } else {
+            $processor = new EnvVarProcessor($this);
+            if (false === $i) {
+                $prefix = '';
+            }
+        }
 
         $this->resolving[$envName] = true;
         try {
diff --git a/src/Symfony/Component/DependencyInjection/EnvVarProcessor.php b/src/Symfony/Component/DependencyInjection/EnvVarProcessor.php
index aec6a79b228cc..818174b3970c7 100644
--- a/src/Symfony/Component/DependencyInjection/EnvVarProcessor.php
+++ b/src/Symfony/Component/DependencyInjection/EnvVarProcessor.php
@@ -126,6 +126,12 @@ public function getEnv(string $prefix, string $name, \Closure $getEnv)
             }
         }
 
+        $returnNull = false;
+        if ('' === $prefix) {
+            $returnNull = true;
+            $prefix = 'string';
+        }
+
         if (false !== $i || 'string' !== $prefix) {
             $env = $getEnv($name);
         } elseif (isset($_ENV[$name])) {
@@ -177,6 +183,10 @@ public function getEnv(string $prefix, string $name, \Closure $getEnv)
         }
 
         if (null === $env) {
+            if ($returnNull) {
+                return null;
+            }
+
             if (!isset($this->getProvidedTypes()[$prefix])) {
                 throw new RuntimeException(sprintf('Unsupported env var prefix "%s".', $prefix));
             }
diff --git a/src/Symfony/Component/DependencyInjection/Tests/EnvVarProcessorTest.php b/src/Symfony/Component/DependencyInjection/Tests/EnvVarProcessorTest.php
index 72cf270a632b6..7ff161c06cee3 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/EnvVarProcessorTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/EnvVarProcessorTest.php
@@ -763,12 +763,13 @@ public static function provideGetEnvUrlPath()
 
     /**
      * @testWith    ["", "string"]
+     *              [null, ""]
      *              [false, "bool"]
      *              [true, "not"]
      *              [0, "int"]
      *              [0.0, "float"]
      */
-    public function testGetEnvCastsNull($expected, string $prefix)
+    public function testGetEnvCastsNullBehavior($expected, string $prefix)
     {
         $processor = new EnvVarProcessor(new Container());
 
@@ -778,4 +779,17 @@ public function testGetEnvCastsNull($expected, string $prefix)
             });
         }));
     }
+
+    public function testGetEnvWithEmptyStringPrefixCastsToString()
+    {
+        $processor = new EnvVarProcessor(new Container());
+        unset($_ENV['FOO']);
+        $_ENV['FOO'] = 4;
+
+        try {
+            $this->assertSame('4', $processor->getEnv('', 'FOO', function () { $this->fail('Should not be called'); }));
+        } finally {
+            unset($_ENV['FOO']);
+        }
+    }
 }