Merge branch '1.8'

CHANGELOG.md

@@ -1,3 +1,7 @@
+### [1.8.3] 2019-01-30
+
+  * Fixed regression when executing partial updates
+
 ### [1.8.2] 2019-01-29
 
   * Fixed invalid deprecation warning for ext-pdo_mysql and similar

src/Composer/Installer.php

@@ -1317,6 +1317,7 @@ class Installer
 
         foreach ($this->updateWhitelist as $packageName => $void) {
             $packageQueue = new \SplQueue;
+            $nameMatchesRequiredPackage = false;
 
             $depPackages = $pool->whatProvides($packageName);
             $matchesByPattern = array();