diff -u b/core/modules/system/lib/Drupal/system/Tests/InstallerTest.php b/core/modules/system/lib/Drupal/system/Tests/InstallerTest.php
--- b/core/modules/system/lib/Drupal/system/Tests/InstallerTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/InstallerTest.php
@@ -100,7 +100,7 @@
     config('system.mail')->set('interface.default', 'Drupal\Core\Mail\VariableLog')->save();
 
     drupal_set_time_limit($this->timeLimit);
-    // When running from run-tests.sh we don't get an mpty current path which
+    // When running from run-tests.sh we don't get an empty current path which
     // would indicate we're on the home page.
     $path = current_path();
     if (empty($path)) {
@@ -112,7 +112,7 @@
   /**
    * Overrides \Drupal\simpletest\WebTestBase::refreshVariables().
    *
-   * During setup(), drupalPost costs refreshVariables which tries to read
+   * During setup(), drupalPost calls refreshVariables() which tries to read
    * variables which are not yet there because the child Drupal is not yet
    * installed.
    */