symfony
diff --git a/‎src/Symfony/Component/Config/Definition/PrototypedArrayNode.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Config/Definition/PrototypedArrayNode.php
+4Lines changed: 4 additions & 0 deletions b/‎src/Symfony/Component/Config/Definition/PrototypedArrayNode.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Config/Definition/PrototypedArrayNode.php
+4Lines changed: 4 additions & 0 deletions
diff --git a/‎src/Symfony/Component/Config/Tests/Definition/NormalizationTest.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Config/Tests/Definition/NormalizationTest.php
+26Lines changed: 26 additions & 0 deletions b/‎src/Symfony/Component/Config/Tests/Definition/NormalizationTest.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Config/Tests/Definition/NormalizationTest.php
+26Lines changed: 26 additions & 0 deletions
@@ -237,6 +237,10 @@ protected function normalizeValue($value)
                 } elseif (isset($v[$this->keyAttribute])) {
                     $k = $v[$this->keyAttribute];
 
+                    if (\is_float($k)) {
+                        $k = var_export($k, true);
+                    }
+
                     // remove the key attribute when required
                     if ($this->removeKeyAttribute) {
                         unset($v[$this->keyAttribute]);
 
@@ -201,6 +201,32 @@ public function testAssociativeArrayPreserveKeys()
         $this->assertNormalized($tree, $data, $data);
     }
 
+    public function testFloatLikeValueAsMapKeyAttribute()
+    {
+        $tree = (new TreeBuilder('root'))
+            ->getRootNode()
+                ->useAttributeAsKey('number')
+                ->arrayPrototype()
+                    ->children()
+                        ->scalarNode('foo')->end()
+                    ->end()
+                ->end()
+            ->end()
+            ->buildTree()
+        ;
+
+        $this->assertNormalized($tree, [
+            [
+                'number' => 3.0,
+                'foo' => 'bar',
+            ],
+        ], [
+            '3.0' => [
+                'foo' => 'bar',
+            ],
+        ]);
+    }
+
     public static function assertNormalized(NodeInterface $tree, $denormalized, $normalized)
     {
         self::assertSame($normalized, $tree->normalize($denormalized));