Resolve #3487705 "Refactor banuserform"

Closes #3487705

tests/src/Functional/PrivateMessageUserBanTest.php

@@ -88,6 +88,46 @@ class PrivateMessageUserBanTest extends BrowserTestBase {
     $this->assertSession()->linkExists('Block');
   }
 
+  /**
+   * Tests access to the ban listing.
+   */
+  public function testBanPageRouteAccess() {
+    $this->drupalLogin($this->userA);
+    $this->drupalGet('/private-message/ban');
+    $this->assertSession()->statusCodeEquals(200);
+    $this->assertSession()->pageTextContains('Ban/Unban users');
+
+    $this->drupalLogout();
+    $this->drupalGet('/private-message/ban');
+    $this->assertSession()->statusCodeEquals(403);
+  }
+
+  /**
+   * Tests for BanUserForm.
+   */
+  public function testBanUserFormSubmission() {
+    $this->drupalLogin($this->userA);
+    $this->drupalGet('/private-message/ban');
+
+    $edit = [
+      'banned_user' => $this->userA->getDisplayName() . ' (' . $this->userA->id() . ')',
+    ];
+    $this->submitForm($edit, 'Block');
+    $this->assertSession()->statusMessageContains("You can't block yourself.", 'error');
+
+    $edit = [
+      'banned_user' => $this->userB->getDisplayName() . ' (' . $this->userB->id() . ')',
+    ];
+    $this->submitForm($edit, 'Block');
+    $this->assertSession()->statusMessageContains("The user " . $this->userB->getDisplayName() . " has been banned.", 'status');
+
+    $edit = [
+      'banned_user' => $this->userB->getDisplayName() . ' (' . $this->userB->id() . ')',
+    ];
+    $this->submitForm($edit, 'Block');
+    $this->assertSession()->statusMessageContains('The user is already blocked', 'error');
+  }
+
   /**
    * Returns a count of bans.
    */