diff --git a/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php b/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php
index 6ca9f85..81da04a 100644
--- a/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php
+++ b/core/tests/Drupal/FunctionalTests/AssertLegacyTrait.php
@@ -129,6 +129,27 @@ protected function assertFieldByName($name, $value = NULL) {
   }
 
   /**
+   * Asserts that a field exists with the given name and value.
+   *
+   * @param string $name
+   *   Name of field to assert.
+   * @param string $value
+   *   (optional) Value of the field to assert. You may pass in NULL (default)
+   *   to skip checking the actual value, while still checking that the field
+   *   exists.
+   *
+   * @deprecated Scheduled for removal in Drupal 9.0.0.
+   *   Use $this->assertSession()->fieldNotExists() or
+   *   $this->assertSession()->fieldValueNotEquals() instead.
+   */
+  protected function assertNoFieldByName($name, $value = NULL) {
+    $this->assertSession()->fieldNotExists($name);
+    if ($value !== NULL) {
+      $this->assertSession()->fieldValueNotEquals($name, (string) $value);
+    }
+  }
+
+  /**
    * Asserts that a field exists with the given ID and value.
    *
    * @param string $id
@@ -344,6 +365,47 @@ protected function assertNoOption($id, $option) {
   }
 
   /**
+   * Asserts that a select option in the current page is checked.
+   *
+   * @param string $id
+   *   ID of select field to assert.
+   * @param string $option
+   *   Option to assert.
+   *
+   * @deprecated Scheduled for removal in Drupal 9.0.0.
+   *   Use $this->assertSession()->optionSelected() instead.
+   */
+  protected function assertOptionSelected($id, $option) {
+    $this->assertSession()->optionSelected($id, $option);
+  }
+
+  /**
+   * Asserts that a checkbox field in the current page is checked.
+   *
+   * @param string $id
+   *   ID of field to assert.
+   *
+   * @deprecated Scheduled for removal in Drupal 9.0.0.
+   *   Use $this->assertSession()->checkboxChecked() instead.
+   */
+  protected function assertFieldChecked($id) {
+    $this->assertSession()->checkboxChecked($id);
+  }
+
+  /**
+   * Asserts that a checkbox field in the current page is not checked.
+   *
+   * @param string $id
+   *   ID of field to assert.
+   *
+   * @deprecated Scheduled for removal in Drupal 9.0.0.
+   *   Use $this->assertSession()->checkboxNotChecked() instead.
+   */
+  protected function assertNoFieldChecked($id) {
+    $this->assertSession()->checkboxNotChecked($id);
+  }
+
+  /**
    * Passes if the raw text IS found escaped on the loaded page, fail otherwise.
    *
    * Raw text refers to the raw HTML that the page generated.
diff --git a/core/tests/Drupal/Tests/WebAssert.php b/core/tests/Drupal/Tests/WebAssert.php
index 6156dda..d4cffd8 100644
--- a/core/tests/Drupal/Tests/WebAssert.php
+++ b/core/tests/Drupal/Tests/WebAssert.php
@@ -191,6 +191,29 @@ public function optionNotExists($select, $option, TraversableElement $container
   }
 
   /**
+   * Checks that a specific option in a select field is selected.
+   *
+   * @param string $select
+   *   One of id|name|label|value for the select field.
+   * @param string $option
+   *   The option value.
+   * @param \Behat\Mink\Element\TraversableElement $container
+   *   (optional) The document to check against. Defaults to the current page.
+   *
+   * @return \Behat\Mink\Element\NodeElement
+   *   The matching option element
+   *
+   * @throws \Behat\Mink\Exception\ElementNotFoundException
+   *   When the element doesn't exist.
+   */
+  public function optionSelected($select, $option, TraversableElement $container = NULL) {
+    $option_field = $this->optionExists($select, $option, $container);
+    $this->assert(!empty($option_field->getAttribute('selected')), sprintf('Option "%s" in select "%s" is not selected as expected.', $option, $select));
+
+    return $option_field;
+  }
+
+  /**
    * Pass if the page title is the given string.
    *
    * @param string $expected_title