feat(assertions): add "Then I see response body contains"

Author: remarkablemark

cypress/e2e/httpbin/get.feature

@@ -6,3 +6,4 @@ Feature: httpbin
   Scenario: GET response body
     Given I make a "GET" request to "https://httpbin.org/base64/SFRUUEJJTiBpcyBhd2Vzb21l"
     Then I see response body "HTTPBIN is awesome"
+      And I see response body contains "awesome"

cypress/e2e/typicode/jsonplaceholder.feature

@@ -3,3 +3,4 @@ Feature: JSONPlaceholder
     Given I make a "GET" request to "https://jsonplaceholder.typicode.com/todos/1"
     Then I see response status 200
       And I see response body '{"userId":1,"id":1,"title":"delectus aut autem","completed":false}'
+      And I see response body contains '{"id":1,"userId":1}'

src/assertions/response.ts

@@ -42,7 +42,7 @@ Then('I see response status {int}', Then_I_see_response_status);
  * @example
  *
  * ```gherkin
- * Then I see response body "OK
+ * Then I see response body "OK"
  * ```
  *
  * @remarks
@@ -57,11 +57,48 @@ Then('I see response status {int}', Then_I_see_response_status);
 export function Then_I_see_response_body(body: string) {
   getCypressElement().should((response: Cypress.Response<object>) => {
     if (typeof response.body === 'object') {
-      expect(response.body).to.eql(JSON.parse(body));
+      expect(response.body).to.deep.equal(JSON.parse(body));
     } else {
       expect(response.body).to.equal(body);
     }
   });
 }
 
 Then('I see response body {string}', Then_I_see_response_body);
+
+/**
+ * Then I see response body contains:
+ *
+ * ```gherkin
+ * Then I see response body contains {string}
+ * ```
+ *
+ * @example
+ *
+ * ```gherkin
+ * Then I see response body contains "OK"
+ * ```
+ *
+ * @remarks
+ *
+ * A preceding step like {@link When_I_make_a_request | "When I make a request"} is required. For example:
+ *
+ * ```gherkin
+ * When I make a "GET" request to "/user.json"
+ * Then I see response body contains '{"name":"Mark"}'
+ * ```
+ */
+export function Then_I_see_response_body_contains(body: string) {
+  getCypressElement().should((response: Cypress.Response<object>) => {
+    if (typeof response.body === 'object') {
+      expect(response.body).to.deep.include(JSON.parse(body));
+    } else {
+      expect(response.body).to.include(body);
+    }
+  });
+}
+
+Then(
+  'I see response body contains {string}',
+  Then_I_see_response_body_contains,
+);