feat(assertions): add "Then I see element exists"

src/assertions/exist.ts

@@ -0,0 +1,33 @@
+import { Then } from '@badeball/cypress-cucumber-preprocessor';
+
+import { getCypressElement } from '../utils';
+
+/**
+ * Then I see element exists:
+ *
+ * ```gherkin
+ * Then I see element exists
+ * ```
+ *
+ * Assert element **_exists_** in the screen.
+ *
+ * @example
+ *
+ * ```gherkin
+ * Then I see element exists
+ * ```
+ *
+ * @remarks
+ *
+ * A preceding step like {@link When_I_find_element_by_text | "When I find element by text"} is required. For example:
+ *
+ * ```gherkin
+ * When I find element by text "Text"
+ * Then I see element exists
+ * ```
+ */
+export function Then_I_see_element_exists() {
+  getCypressElement().should('exist');
+}
+
+Then('I see element exists', Then_I_see_element_exists);

src/assertions/index.ts

@@ -3,6 +3,7 @@ export * from './button';
 export * from './cookie';
 export * from './count';
 export * from './document-title';
+export * from './exist';
 export * from './hash';
 export * from './heading';
 export * from './label';