From 5ee7fabbf948f3a759f5cfd9f76c72eef17694c8 Mon Sep 17 00:00:00 2001
From: drlibra <13391053+drlibra@users.noreply.github.com>
Date: Mon, 10 Sep 2018 01:44:10 +0500
Subject: [PATCH] Fixes #16552: Added check in `yii\db\ActiveQuery::prepare()`
 to prevent populating already populated relation when another relation is
 requested with `via`

---
 framework/CHANGELOG.md            |  1 +
 framework/db/ActiveQuery.php      | 16 ++++++++++++----
 framework/db/BaseActiveRecord.php | 12 ++++++++----
 3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index 48c96e8da6..6fdd16f3ed 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -49,6 +49,7 @@ Yii Framework 2 Change Log
 - Enh #16603: Added `yii\mutex\FileMutex::$isWindows` for Windows file shares on Unix guest machines (brandonkelly)
 - Bug #16666: Fixed `yii\helpers\ArrayHelper::merge` (rustamwin)
 - Enh: `yii\helpers\UnsetArrayValue`, `yii\helpers\ReplaceArrayValue` object now can be restored after serialization using `var_export()` function (silvefire)
+- Bug #16552: Added check in `yii\db\ActiveQuery::prepare()` to prevent populating already populated relation when another relation is requested with `via` (drlibra)
 
 2.0.15.1 March 21, 2018
 -----------------------
diff --git a/framework/db/ActiveQuery.php b/framework/db/ActiveQuery.php
index 46086fbbab..5af019e441 100644
--- a/framework/db/ActiveQuery.php
+++ b/framework/db/ActiveQuery.php
@@ -172,11 +172,19 @@ class ActiveQuery extends Query implements ActiveQueryInterface
                 /* @var $viaQuery ActiveQuery */
                 list($viaName, $viaQuery) = $this->via;
                 if ($viaQuery->multiple) {
-                    $viaModels = $viaQuery->all();
-                    $this->primaryModel->populateRelation($viaName, $viaModels);
+                    if ($this->primaryModel->isRelationPopulated($viaName)) {
+                        $viaModels = $this->primaryModel->$viaName;
+                    } else {
+                        $viaModels = $viaQuery->all();
+                        $this->primaryModel->populateRelation($viaName, $viaModels);
+                    }
                 } else {
-                    $model = $viaQuery->one();
-                    $this->primaryModel->populateRelation($viaName, $model);
+                    if ($this->primaryModel->isRelationPopulated($viaName)) {
+                        $model = $this->primaryModel->$viaName;
+                    } else {
+                        $model = $viaQuery->one();
+                        $this->primaryModel->populateRelation($viaName, $model);
+                    }
                     $viaModels = $model === null ? [] : [$model];
                 }
                 $this->filterByModels($viaModels);
diff --git a/framework/db/BaseActiveRecord.php b/framework/db/BaseActiveRecord.php
index e19b0a8fbb..cc47375f64 100644
--- a/framework/db/BaseActiveRecord.php
+++ b/framework/db/BaseActiveRecord.php
@@ -223,7 +223,7 @@ abstract class BaseActiveRecord extends Model implements ActiveRecordInterface
      * 1. Create a column to store the version number of each row. The column type should be `BIGINT DEFAULT 0`.
      *    Override this method to return the name of this column.
      * 2. Ensure the version value is submitted and loaded to your model before any update or delete.
-     *    Or add [[\yii\behaviors\OptimisticLockBehavior|OptimisticLockBehavior]] to your model 
+     *    Or add [[\yii\behaviors\OptimisticLockBehavior|OptimisticLockBehavior]] to your model
      *    class in order to automate the process.
      * 3. In the Web form that collects the user input, add a hidden field that stores
      *    the lock version of the recording being updated.
@@ -1734,18 +1734,22 @@ abstract class BaseActiveRecord extends Model implements ActiveRecordInterface
      * Sets relation dependencies for a property
      * @param string $name property name
      * @param ActiveQueryInterface $relation relation instance
+     * @param string|null $viaRelationName intermediate relation
      */
-    private function setRelationDependencies($name, $relation)
+    private function setRelationDependencies($name, $relation, $viaRelationName = null)
     {
         if (empty($relation->via) && $relation->link) {
             foreach ($relation->link as $attribute) {
                 $this->_relationsDependencies[$attribute][$name] = $name;
+                if ($viaRelationName !== null) {
+                    $this->_relationsDependencies[$attribute][] = $viaRelationName;
+                }
             }
         } elseif ($relation->via instanceof ActiveQueryInterface) {
             $this->setRelationDependencies($name, $relation->via);
         } elseif (is_array($relation->via)) {
-            list(, $viaQuery) = $relation->via;
-            $this->setRelationDependencies($name, $viaQuery);
+            list($viaRelationName, $viaQuery) = $relation->via;
+            $this->setRelationDependencies($name, $viaQuery, $viaRelationName);
         }
     }
 }