From dee15623ae4a008b10027ab87803f3136c41ebbd Mon Sep 17 00:00:00 2001
From: Tobias Schultze <webmaster@tubo-world.de>
Date: Wed, 18 Jun 2014 19:47:01 +0200
Subject: [PATCH] [Yaml] fix overwriting of keys after merged map

fixes symfony/symfony#11142
---
 src/Symfony/Component/Yaml/Parser.php         | 17 ++++++++--------
 .../Yaml/Tests/Fixtures/sfMergeKey.yml        | 20 +++++++++++++++++--
 2 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/src/Symfony/Component/Yaml/Parser.php b/src/Symfony/Component/Yaml/Parser.php
index 05c2db67cf76..0577b5e8853b 100644
--- a/src/Symfony/Component/Yaml/Parser.php
+++ b/src/Symfony/Component/Yaml/Parser.php
@@ -66,6 +66,7 @@ public function parse($value, $exceptionOnInvalidType = false, $objectSupport =
 
         $data = array();
         $context = null;
+        $allowOverwrite = false;
         while ($this->moveToNextLine()) {
             if ($this->isCurrentLineEmpty()) {
                 continue;
@@ -133,6 +134,7 @@ public function parse($value, $exceptionOnInvalidType = false, $objectSupport =
 
                 if ('<<' === $key) {
                     $mergeNode = true;
+                    $allowOverwrite = true;
                     if (isset($values['value']) && 0 === strpos($values['value'], '*')) {
                         $refName = substr($values['value'], 1);
                         if (!array_key_exists($refName, $this->refs)) {
@@ -202,9 +204,8 @@ public function parse($value, $exceptionOnInvalidType = false, $objectSupport =
                     // if next line is less indented or equal, then it means that the current value is null
                     if (!$this->isNextLineIndented() && !$this->isNextLineUnIndentedCollection()) {
                         // Spec: Keys MUST be unique; first one wins.
-                        // Parser cannot abort this mapping earlier, since lines
-                        // are processed sequentially.
-                        if (!isset($data[$key])) {
+                        // But overwriting is allowed when a merge node is used in current block.
+                        if ($allowOverwrite || !isset($data[$key])) {
                             $data[$key] = null;
                         }
                     } else {
@@ -213,18 +214,16 @@ public function parse($value, $exceptionOnInvalidType = false, $objectSupport =
                         $parser->refs =& $this->refs;
                         $value = $parser->parse($this->getNextEmbedBlock(), $exceptionOnInvalidType, $objectSupport);
                         // Spec: Keys MUST be unique; first one wins.
-                        // Parser cannot abort this mapping earlier, since lines
-                        // are processed sequentially.
-                        if (!isset($data[$key])) {
+                        // But overwriting is allowed when a merge node is used in current block.
+                        if ($allowOverwrite || !isset($data[$key])) {
                             $data[$key] = $value;
                         }
                     }
                 } else {
                     $value = $this->parseValue($values['value'], $exceptionOnInvalidType, $objectSupport);
                     // Spec: Keys MUST be unique; first one wins.
-                    // Parser cannot abort this mapping earlier, since lines
-                    // are processed sequentially.
-                    if (!isset($data[$key])) {
+                    // But overwriting is allowed when a merge node is used in current block.
+                    if ($allowOverwrite || !isset($data[$key])) {
                         $data[$key] = $value;
                     }
                 }
diff --git a/src/Symfony/Component/Yaml/Tests/Fixtures/sfMergeKey.yml b/src/Symfony/Component/Yaml/Tests/Fixtures/sfMergeKey.yml
index c04943eec1d3..fd9910174dad 100644
--- a/src/Symfony/Component/Yaml/Tests/Fixtures/sfMergeKey.yml
+++ b/src/Symfony/Component/Yaml/Tests/Fixtures/sfMergeKey.yml
@@ -10,11 +10,19 @@ yaml: |
         a: Steve
         b: Clark
         c: Brian
-    bar: &bar
+    bar:
         a: before
         d: other
         <<: *foo
+        b: new
         x: Oren
+        c:
+            foo: bar
+            foo: ignore
+            bar: foo
+    duplicate:
+        foo: bar
+        foo: ignore
     foo2: &foo2
         a: Ballmer
     ding: &dong [ fi, fei, fo, fam]
@@ -26,4 +34,12 @@ yaml: |
     head:
         <<: [ *foo , *dong , *foo2 ]
 php: |
-    array('foo' => array('a' => 'Steve', 'b' => 'Clark', 'c' => 'Brian'), 'bar' => array('a' => 'before', 'd' => 'other', 'b' => 'Clark', 'c' => 'Brian', 'x' => 'Oren'), 'foo2' => array('a' => 'Ballmer'), 'ding' => array('fi', 'fei', 'fo', 'fam'), 'check' => array('a' => 'Steve', 'b' => 'Clark', 'c' => 'Brian', 'fi', 'fei', 'fo', 'fam', 'isit' => 'tested'), 'head' => array('a' => 'Steve', 'b' => 'Clark', 'c' => 'Brian', 'fi', 'fei', 'fo', 'fam'))
+    array(
+        'foo' => array('a' => 'Steve', 'b' => 'Clark', 'c' => 'Brian'),
+        'bar' => array('a' => 'before', 'd' => 'other', 'b' => 'new', 'c' => array('foo' => 'bar', 'bar' => 'foo'), 'x' => 'Oren'),
+        'duplicate' => array('foo' => 'bar'),
+        'foo2' => array('a' => 'Ballmer'),
+        'ding' => array('fi', 'fei', 'fo', 'fam'),
+        'check' => array('a' => 'Steve', 'b' => 'Clark', 'c' => 'Brian', 'fi', 'fei', 'fo', 'fam', 'isit' => 'tested'),
+        'head' => array('a' => 'Steve', 'b' => 'Clark', 'c' => 'Brian', 'fi', 'fei', 'fo', 'fam')
+    )