diff --git a/core/modules/page_cache/src/Tests/PageCacheTagsIntegrationTest.php b/core/modules/page_cache/tests/src/Functional/PageCacheTagsIntegrationTest.php
similarity index 91%
rename from core/modules/page_cache/src/Tests/PageCacheTagsIntegrationTest.php
rename to core/modules/page_cache/tests/src/Functional/PageCacheTagsIntegrationTest.php
index be704d16ed..6a4b47eaba 100644
--- a/core/modules/page_cache/src/Tests/PageCacheTagsIntegrationTest.php
+++ b/core/modules/page_cache/tests/src/Functional/PageCacheTagsIntegrationTest.php
@@ -1,22 +1,20 @@
 <?php
 
-namespace Drupal\page_cache\Tests;
+namespace Drupal\Tests\page_cache\Functional;
 
 use Drupal\Core\EventSubscriber\MainContentViewSubscriber;
 use Drupal\Core\Language\LanguageInterface;
-use Drupal\simpletest\WebTestBase;
 use Drupal\node\NodeInterface;
+use Drupal\Tests\BrowserTestBase;
 use Drupal\Tests\system\Functional\Cache\AssertPageCacheContextsAndTagsTrait;
 
 /**
  * Enables the page cache and tests its cache tags in various scenarios.
  *
  * @group Cache
- * @see \Drupal\page_cache\Tests\PageCacheTest
- * @see \Drupal\node\Tests\NodePageCacheTest
- * @see \Drupal\menu_ui\Tests\MenuTest::testMenuBlockPageCacheTags()
+ * @see \Drupal\Tests\page_cache\Functional\PageCacheTest
  */
-class PageCacheTagsIntegrationTest extends WebTestBase {
+class PageCacheTagsIntegrationTest extends BrowserTestBase {
 
   use AssertPageCacheContextsAndTagsTrait;
 
@@ -79,7 +77,7 @@ public function testPageCacheTags() {
     ];
 
     // Full node page 1.
-    $this->assertPageCacheContextsAndTags($node_1->urlInfo(), $cache_contexts, [
+    $this->assertPageCacheContextsAndTags($node_1->toUrl(), $cache_contexts, [
       'http_response',
       'rendered',
       'block_view',
@@ -120,7 +118,7 @@ public function testPageCacheTags() {
     $cache_contexts[] = 'languages:' . LanguageInterface::TYPE_CONTENT;
 
     // Full node page 2.
-    $this->assertPageCacheContextsAndTags($node_2->urlInfo(), $cache_contexts, [
+    $this->assertPageCacheContextsAndTags($node_2->toUrl(), $cache_contexts, [
       'http_response',
       'rendered',
       'block_view',
diff --git a/core/modules/page_cache/src/Tests/PageCacheTest.php b/core/modules/page_cache/tests/src/Functional/PageCacheTest.php
similarity index 53%
rename from core/modules/page_cache/src/Tests/PageCacheTest.php
rename to core/modules/page_cache/tests/src/Functional/PageCacheTest.php
index cb00cb6861..326d7d5f9f 100644
--- a/core/modules/page_cache/src/Tests/PageCacheTest.php
+++ b/core/modules/page_cache/tests/src/Functional/PageCacheTest.php
@@ -1,12 +1,13 @@
 <?php
 
-namespace Drupal\page_cache\Tests;
+namespace Drupal\Tests\page_cache\Functional;
 
 use Drupal\Component\Datetime\DateTimePlus;
 use Drupal\Core\Site\Settings;
 use Drupal\Core\Url;
 use Drupal\entity_test\Entity\EntityTest;
-use Drupal\simpletest\WebTestBase;
+use Drupal\Tests\BrowserTestBase;
+use Drupal\Tests\system\Functional\Cache\AssertPageCacheContextsAndTagsTrait;
 use Drupal\Core\Cache\Cache;
 use Drupal\user\RoleInterface;
 
@@ -15,7 +16,9 @@
  *
  * @group page_cache
  */
-class PageCacheTest extends WebTestBase {
+class PageCacheTest extends BrowserTestBase {
+
+  use AssertPageCacheContextsAndTagsTrait;
 
   protected $dumpHeaders = TRUE;
 
@@ -45,19 +48,20 @@ protected function setUp() {
    * persisted.
    */
   public function testPageCacheTags() {
-    $config = $this->config('system.performance');
-    $config->set('cache.page.max_age', 300);
-    $config->save();
+    $this->enablePageCaching();
 
     $path = 'system-test/cache_tags_page';
     $tags = ['system_test_cache_tags_page'];
     $this->drupalGet($path);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
 
     // Verify a cache hit, but also the presence of the correct cache tags.
     $this->drupalGet($path);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
-    $cid_parts = [\Drupal::url('system_test.cache_tags_page', [], ['absolute' => TRUE]), 'html'];
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'));
+    $cid_parts = [
+      Url::fromRoute('system_test.cache_tags_page')->setAbsolute()->toString(),
+      'html',
+    ];
     $cid = implode(':', $cid_parts);
     $cache_entry = \Drupal::cache('page')->get($cid);
     sort($cache_entry->tags);
@@ -68,28 +72,34 @@ public function testPageCacheTags() {
       'rendered',
       'system_test_cache_tags_page',
     ];
-    $this->assertIdentical($cache_entry->tags, $expected_tags);
+    $this->assertSame($expected_tags, $cache_entry->tags);
 
     Cache::invalidateTags($tags);
     $this->drupalGet($path);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
   }
 
   /**
    * Test that the page cache doesn't depend on cacheability headers.
    */
   public function testPageCacheTagsIndependentFromCacheabilityHeaders() {
-    $this->setHttpResponseDebugCacheabilityHeaders(FALSE);
+    // Disable the cacheability headers.
+    $this->setContainerParameter('http.response.debug_cacheability_headers', FALSE);
+    $this->rebuildContainer();
+    $this->resetAll();
 
     $path = 'system-test/cache_tags_page';
     $tags = ['system_test_cache_tags_page'];
     $this->drupalGet($path);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
 
     // Verify a cache hit, but also the presence of the correct cache tags.
     $this->drupalGet($path);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
-    $cid_parts = [\Drupal::url('system_test.cache_tags_page', [], ['absolute' => TRUE]), 'html'];
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'));
+    $cid_parts = [
+      Url::fromRoute('system_test.cache_tags_page')->setAbsolute()->toString(),
+      'html',
+    ];
     $cid = implode(':', $cid_parts);
     $cache_entry = \Drupal::cache('page')->get($cid);
     sort($cache_entry->tags);
@@ -100,11 +110,11 @@ public function testPageCacheTagsIndependentFromCacheabilityHeaders() {
       'rendered',
       'system_test_cache_tags_page',
     ];
-    $this->assertIdentical($cache_entry->tags, $expected_tags);
+    $this->assertSame($expected_tags, $cache_entry->tags);
 
     Cache::invalidateTags($tags);
     $this->drupalGet($path);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
   }
 
   /**
@@ -112,107 +122,127 @@ public function testPageCacheTagsIndependentFromCacheabilityHeaders() {
    * specified via a query parameter.
    */
   public function testQueryParameterFormatRequests() {
-    $config = $this->config('system.performance');
-    $config->set('cache.page.max_age', 300);
-    $config->save();
+    $this->enablePageCaching();
 
     $accept_header_cache_url = Url::fromRoute('system_test.page_cache_accept_header');
     $accept_header_cache_url_with_json = Url::fromRoute('system_test.page_cache_accept_header', ['_format' => 'json']);
 
     $this->drupalGet($accept_header_cache_url);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'HTML page was not yet cached.');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'), 'HTML page was not yet cached.');
     $this->drupalGet($accept_header_cache_url);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'HTML page was cached.');
-    $this->assertRaw('<p>oh hai this is html.</p>', 'The correct HTML response was returned.');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), 'HTML page was cached.');
+    $this->assertSession()->responseContains('<p>oh hai this is html.</p>');
 
     $this->drupalGet($accept_header_cache_url_with_json);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Json response was not yet cached.');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'), 'Json response was not yet cached.');
     $this->drupalGet($accept_header_cache_url_with_json);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Json response was cached.');
-    $this->assertRaw('{"content":"oh hai this is json"}', 'The correct Json response was returned.');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), 'Json response was cached.');
+    $this->assertSession()->responseContains('{"content":"oh hai this is json"}');
 
     // Enable REST support for nodes and hal+json.
-    \Drupal::service('module_installer')->install(['node', 'rest', 'hal', 'basic_auth']);
+    \Drupal::service('module_installer')->install([
+      'node',
+      'rest',
+      'hal',
+      'basic_auth',
+    ]);
     $this->drupalCreateContentType(['type' => 'article']);
     $node = $this->drupalCreateNode(['type' => 'article']);
-    $node_uri = $node->urlInfo();
-    $node_url_with_hal_json_format = $node->urlInfo('canonical')->setRouteParameter('_format', 'hal_json');
+    $node_uri = $node->toUrl();
+    $node_url_with_hal_json_format = $node->toUrl()->setRouteParameter('_format', 'hal_json');
 
     $this->drupalGet($node_uri);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
-    $this->assertEqual($this->drupalGetHeader('Content-Type'), 'text/html; charset=UTF-8');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
+    $this->assertEquals('text/html; charset=UTF-8', $this->drupalGetHeader('Content-Type'));
     $this->drupalGet($node_uri);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
-    $this->assertEqual($this->drupalGetHeader('Content-Type'), 'text/html; charset=UTF-8');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'));
+    $this->assertEquals('text/html; charset=UTF-8', $this->drupalGetHeader('Content-Type'));
 
     // Now request a HAL page, we expect that the first request is a cache miss
     // and it serves HTML.
     $this->drupalGet($node_url_with_hal_json_format);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
-    $this->assertEqual($this->drupalGetHeader('Content-Type'), 'application/hal+json');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
+    $this->assertEquals('application/hal+json', $this->drupalGetHeader('Content-Type'));
     $this->drupalGet($node_url_with_hal_json_format);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
-    $this->assertEqual($this->drupalGetHeader('Content-Type'), 'application/hal+json');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'));
+    $this->assertEquals('application/hal+json', $this->drupalGetHeader('Content-Type'));
 
     // Clear the page cache. After that request a HAL request, followed by an
     // ordinary HTML one.
     \Drupal::cache('page')->deleteAll();
     $this->drupalGet($node_url_with_hal_json_format);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
-    $this->assertEqual($this->drupalGetHeader('Content-Type'), 'application/hal+json');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
+    $this->assertEquals('application/hal+json', $this->drupalGetHeader('Content-Type'));
     $this->drupalGet($node_url_with_hal_json_format);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
-    $this->assertEqual($this->drupalGetHeader('Content-Type'), 'application/hal+json');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'));
+    $this->assertEquals('application/hal+json', $this->drupalGetHeader('Content-Type'));
 
     $this->drupalGet($node_uri);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
-    $this->assertEqual($this->drupalGetHeader('Content-Type'), 'text/html; charset=UTF-8');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
+    $this->assertEquals('text/html; charset=UTF-8', $this->drupalGetHeader('Content-Type'));
     $this->drupalGet($node_uri);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
-    $this->assertEqual($this->drupalGetHeader('Content-Type'), 'text/html; charset=UTF-8');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'));
+    $this->assertEquals('text/html; charset=UTF-8', $this->drupalGetHeader('Content-Type'));
   }
 
   /**
    * Tests support of requests with If-Modified-Since and If-None-Match headers.
    */
   public function testConditionalRequests() {
-    $config = $this->config('system.performance');
-    $config->set('cache.page.max_age', 300);
-    $config->save();
+    $this->enablePageCaching();
 
     // Fill the cache.
     $this->drupalGet('');
     // Verify the page is not printed twice when the cache is cold.
-    $this->assertNoPattern('#<html.*<html#');
+    $this->assertSession()->responseNotMatches('#<html.*<html#');
 
-    $this->drupalHead('');
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
+    // Check cache.
+    $this->drupalGet('');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was cached.');
     $etag = $this->drupalGetHeader('ETag');
     $last_modified = $this->drupalGetHeader('Last-Modified');
 
-    $this->drupalGet('', [], ['If-Modified-Since: ' . $last_modified, 'If-None-Match: ' . $etag]);
-    $this->assertResponse(304, 'Conditional request returned 304 Not Modified.');
-
-    $this->drupalGet('', [], ['If-Modified-Since: ' . gmdate(DATE_RFC822, strtotime($last_modified)), 'If-None-Match: ' . $etag]);
-    $this->assertResponse(304, 'Conditional request with obsolete If-Modified-Since date returned 304 Not Modified.');
-
-    $this->drupalGet('', [], ['If-Modified-Since: ' . gmdate(DATE_RFC850, strtotime($last_modified)), 'If-None-Match: ' . $etag]);
-    $this->assertResponse(304, 'Conditional request with obsolete If-Modified-Since date returned 304 Not Modified.');
-
-    $this->drupalGet('', [], ['If-Modified-Since: ' . $last_modified]);
+    $this->drupalGet('', [], [
+      'If-Modified-Since' => $last_modified,
+      'If-None-Match' => $etag,
+    ]);
+    $this->assertSession()->statusCodeEquals(304);
+
+    $this->drupalGet('', [], [
+      'If-Modified-Since' => gmdate(DATE_RFC822, strtotime($last_modified)),
+      'If-None-Match' => $etag,
+    ]);
+    $this->assertSession()->statusCodeEquals(304);
+
+    $this->drupalGet('', [], [
+      'If-Modified-Since' => gmdate(DATE_RFC850, strtotime($last_modified)),
+      'If-None-Match' => $etag,
+    ]);
+    $this->assertSession()->statusCodeEquals(304);
+
+    $this->drupalGet('', [], [
+      'If-Modified-Since' => $last_modified,
+      'If-None-Match' => NULL,
+    ]);
     // Verify the page is not printed twice when the cache is warm.
-    $this->assertNoPattern('#<html.*<html#');
-    $this->assertResponse(200, 'Conditional request without If-None-Match returned 200 OK.');
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
+    $this->assertSession()->responseNotMatches('#<html.*<html#');
+    $this->assertSession()->statusCodeEquals(200);
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was cached.');
 
-    $this->drupalGet('', [], ['If-Modified-Since: ' . gmdate(DateTimePlus::RFC7231, strtotime($last_modified) + 1), 'If-None-Match: ' . $etag]);
-    $this->assertResponse(200, 'Conditional request with new a If-Modified-Since date newer than Last-Modified returned 200 OK.');
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
+    $this->drupalGet('', [], [
+      'If-Modified-Since' => gmdate(DateTimePlus::RFC7231, strtotime($last_modified) + 1),
+      'If-None-Match' => $etag,
+    ]);
+    $this->assertSession()->statusCodeEquals(200);
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was cached.');
 
     $user = $this->drupalCreateUser();
     $this->drupalLogin($user);
-    $this->drupalGet('', [], ['If-Modified-Since: ' . $last_modified, 'If-None-Match: ' . $etag]);
-    $this->assertResponse(200, 'Conditional request returned 200 OK for authenticated user.');
+    $this->drupalGet('', [], [
+      'If-Modified-Since' => $last_modified,
+      'If-None-Match' => $etag,
+    ]);
+    $this->assertSession()->statusCodeEquals(200);
     $this->assertFalse($this->drupalGetHeader('X-Drupal-Cache'), 'Absence of Page was not cached.');
   }
 
@@ -220,34 +250,32 @@ public function testConditionalRequests() {
    * Tests cache headers.
    */
   public function testPageCache() {
-    $config = $this->config('system.performance');
-    $config->set('cache.page.max_age', 300);
-    $config->save();
+    $this->enablePageCaching();
 
     // Fill the cache.
     $this->drupalGet('system-test/set-header', ['query' => ['name' => 'Foo', 'value' => 'bar']]);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Page was not cached.');
-    $this->assertEqual(strtolower($this->drupalGetHeader('Vary')), 'cookie,accept-encoding', 'Vary header was sent.');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was not cached.');
+    $this->assertEquals('cookie,accept-encoding', strtolower($this->drupalGetHeader('Vary')), 'Vary header was sent.');
     // Symfony's Response logic determines a specific order for the subvalues
     // of the Cache-Control header, even if they are explicitly passed in to
     // the response header bag in a different order.
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public', 'Cache-Control header was sent.');
-    $this->assertEqual($this->drupalGetHeader('Expires'), 'Sun, 19 Nov 1978 05:00:00 GMT', 'Expires header was sent.');
-    $this->assertEqual($this->drupalGetHeader('Foo'), 'bar', 'Custom header was sent.');
+    $this->assertEquals('max-age=300, public', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent.');
+    $this->assertEquals('Sun, 19 Nov 1978 05:00:00 GMT', $this->drupalGetHeader('Expires'), 'Expires header was sent.');
+    $this->assertEquals('bar', $this->drupalGetHeader('Foo'), 'Custom header was sent.');
 
     // Check cache.
     $this->drupalGet('system-test/set-header', ['query' => ['name' => 'Foo', 'value' => 'bar']]);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
-    $this->assertEqual(strtolower($this->drupalGetHeader('Vary')), 'cookie,accept-encoding', 'Vary: Cookie header was sent.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public', 'Cache-Control header was sent.');
-    $this->assertEqual($this->drupalGetHeader('Expires'), 'Sun, 19 Nov 1978 05:00:00 GMT', 'Expires header was sent.');
-    $this->assertEqual($this->drupalGetHeader('Foo'), 'bar', 'Custom header was sent.');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was cached.');
+    $this->assertEquals('cookie,accept-encoding', strtolower($this->drupalGetHeader('Vary')), 'Vary: Cookie header was sent.');
+    $this->assertEquals('max-age=300, public', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent.');
+    $this->assertEquals('Sun, 19 Nov 1978 05:00:00 GMT', $this->drupalGetHeader('Expires'), 'Expires header was sent.');
+    $this->assertEquals('bar', $this->drupalGetHeader('Foo'), 'Custom header was sent.');
 
     // Check replacing default headers.
     $this->drupalGet('system-test/set-header', ['query' => ['name' => 'Expires', 'value' => 'Fri, 19 Nov 2008 05:00:00 GMT']]);
-    $this->assertEqual($this->drupalGetHeader('Expires'), 'Fri, 19 Nov 2008 05:00:00 GMT', 'Default header was replaced.');
+    $this->assertEquals('Fri, 19 Nov 2008 05:00:00 GMT', $this->drupalGetHeader('Expires'), 'Default header was replaced.');
     $this->drupalGet('system-test/set-header', ['query' => ['name' => 'Vary', 'value' => 'User-Agent']]);
-    $this->assertEqual(strtolower($this->drupalGetHeader('Vary')), 'user-agent,accept-encoding', 'Default header was replaced.');
+    $this->assertEquals('user-agent,accept-encoding', strtolower($this->drupalGetHeader('Vary')), 'Default header was replaced.');
 
     // Check that authenticated users bypass the cache.
     $user = $this->drupalCreateUser();
@@ -255,15 +283,15 @@ public function testPageCache() {
     $this->drupalGet('system-test/set-header', ['query' => ['name' => 'Foo', 'value' => 'bar']]);
     $this->assertFalse($this->drupalGetHeader('X-Drupal-Cache'), 'Caching was bypassed.');
     $this->assertTrue(strpos(strtolower($this->drupalGetHeader('Vary')), 'cookie') === FALSE, 'Vary: Cookie header was not sent.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'must-revalidate, no-cache, private', 'Cache-Control header was sent.');
-    $this->assertEqual($this->drupalGetHeader('Expires'), 'Sun, 19 Nov 1978 05:00:00 GMT', 'Expires header was sent.');
-    $this->assertEqual($this->drupalGetHeader('Foo'), 'bar', 'Custom header was sent.');
+    $this->assertEquals('must-revalidate, no-cache, private', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent.');
+    $this->assertEquals('Sun, 19 Nov 1978 05:00:00 GMT', $this->drupalGetHeader('Expires'), 'Expires header was sent.');
+    $this->assertEquals('bar', $this->drupalGetHeader('Foo'), 'Custom header was sent.');
 
     // Until bubbling of max-age up to the response is supported, verify that
     // a custom #cache max-age set on an element does not affect page max-age.
     $this->drupalLogout();
     $this->drupalGet('system-test/cache_maxage_page');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public');
+    $this->assertEquals('max-age=300, public', $this->drupalGetHeader('Cache-Control'));
   }
 
   /**
@@ -280,52 +308,50 @@ public function testPageCache() {
    * roles.
    */
   public function testPageCacheAnonymousRolePermissions() {
-    $config = $this->config('system.performance');
-    $config->set('cache.page.max_age', 300);
-    $config->save();
+    $this->enablePageCaching();
 
     $content_url = Url::fromRoute('system_test.permission_dependent_content');
     $route_access_url = Url::fromRoute('system_test.permission_dependent_route_access');
 
     // 1. anonymous user, without permission.
     $this->drupalGet($content_url);
-    $this->assertText('Permission to pet llamas: no!');
+    $this->assertTextHelper('Permission to pet llamas: no!', FALSE);
     $this->assertCacheContext('user.permissions');
-    $this->assertCacheTag('config:user.role.anonymous');
+    $this->assertSession()->responseHeaderContains('X-Drupal-Cache-Tags', 'config:user.role.anonymous');
     $this->drupalGet($route_access_url);
     $this->assertCacheContext('user.permissions');
-    $this->assertCacheTag('config:user.role.anonymous');
+    $this->assertSession()->responseHeaderContains('X-Drupal-Cache-Tags', 'config:user.role.anonymous');
 
     // 2. anonymous user, with permission.
     user_role_grant_permissions(RoleInterface::ANONYMOUS_ID, ['pet llamas']);
     $this->drupalGet($content_url);
-    $this->assertText('Permission to pet llamas: yes!');
+    $this->assertTextHelper('Permission to pet llamas: yes!', FALSE);
     $this->assertCacheContext('user.permissions');
-    $this->assertCacheTag('config:user.role.anonymous');
+    $this->assertSession()->responseHeaderContains('X-Drupal-Cache-Tags', 'config:user.role.anonymous');
     $this->drupalGet($route_access_url);
     $this->assertCacheContext('user.permissions');
-    $this->assertCacheTag('config:user.role.anonymous');
+    $this->assertSession()->responseHeaderContains('X-Drupal-Cache-Tags', 'config:user.role.anonymous');
 
     // 3. authenticated user, without permission.
     $auth_user = $this->drupalCreateUser();
     $this->drupalLogin($auth_user);
     $this->drupalGet($content_url);
-    $this->assertText('Permission to pet llamas: no!');
+    $this->assertTextHelper('Permission to pet llamas: no!', FALSE);
     $this->assertCacheContext('user.permissions');
-    $this->assertNoCacheTag('config:user.role.authenticated');
+    $this->assertSession()->responseHeaderNotContains('X-Drupal-Cache-Tags', 'config:user.role.authenticated');
     $this->drupalGet($route_access_url);
     $this->assertCacheContext('user.permissions');
-    $this->assertNoCacheTag('config:user.role.authenticated');
+    $this->assertSession()->responseHeaderNotContains('X-Drupal-Cache-Tags', 'config:user.role.authenticated');
 
     // 4. authenticated user, with permission.
     user_role_grant_permissions(RoleInterface::AUTHENTICATED_ID, ['pet llamas']);
     $this->drupalGet($content_url);
-    $this->assertText('Permission to pet llamas: yes!');
+    $this->assertTextHelper('Permission to pet llamas: yes!', FALSE);
     $this->assertCacheContext('user.permissions');
-    $this->assertNoCacheTag('config:user.role.authenticated');
+    $this->assertSession()->responseHeaderNotContains('X-Drupal-Cache-Tags', 'config:user.role.authenticated');
     $this->drupalGet($route_access_url);
     $this->assertCacheContext('user.permissions');
-    $this->assertNoCacheTag('config:user.role.authenticated');
+    $this->assertSession()->responseHeaderNotContains('X-Drupal-Cache-Tags', 'config:user.role.authenticated');
   }
 
   /**
@@ -342,12 +368,12 @@ public function testPageCacheAnonymous403404() {
     foreach ($tests as $code => $content_url) {
       // Anonymous user, without permissions.
       $this->drupalGet($content_url);
-      $this->assertResponse($code);
-      $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
-      $this->assertCacheTag('4xx-response');
+      $this->assertSession()->statusCodeEquals($code);
+      $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
+      $this->assertSession()->responseHeaderContains('X-Drupal-Cache-Tags', '4xx-response');
       $this->drupalGet($content_url);
-      $this->assertResponse($code);
-      $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
+      $this->assertSession()->statusCodeEquals($code);
+      $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'));
       $entity_values = [
         'name' => $this->randomMachineName(),
         'user_id' => 1,
@@ -355,23 +381,23 @@ public function testPageCacheAnonymous403404() {
           0 => [
             'value' => $this->randomString(),
             'format' => 'plain_text',
-          ]
+          ],
         ],
       ];
       $entity = EntityTest::create($entity_values);
       $entity->save();
       // Saving an entity clears 4xx cache tag.
       $this->drupalGet($content_url);
-      $this->assertResponse($code);
-      $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+      $this->assertSession()->statusCodeEquals($code);
+      $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
       $this->drupalGet($content_url);
-      $this->assertResponse($code);
-      $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT');
+      $this->assertSession()->statusCodeEquals($code);
+      $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'));
       // Rebuilding the router should invalidate the 4xx cache tag.
-      $this->container->get('router.builder')->rebuild();
+      \Drupal::service('router.builder')->rebuild();
       $this->drupalGet($content_url);
-      $this->assertResponse($code);
-      $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+      $this->assertSession()->statusCodeEquals($code);
+      $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
 
       // Ensure the 'expire' field on the cache entry uses cache_ttl_4xx.
       $cache_item = \Drupal::service('cache.page')->get($this->getUrl() . ':html');
@@ -399,8 +425,8 @@ public function testPageCacheAnonymous403404() {
       // Getting the 404 page twice should still result in a cache miss.
       $this->drupalGet($content_url);
       $this->drupalGet($content_url);
-      $this->assertResponse($code);
-      $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+      $this->assertSession()->statusCodeEquals($code);
+      $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
     }
   }
 
@@ -408,9 +434,7 @@ public function testPageCacheAnonymous403404() {
    * Tests the omit_vary_cookie setting.
    */
   public function testPageCacheWithoutVaryCookie() {
-    $config = $this->config('system.performance');
-    $config->set('cache.page.max_age', 300);
-    $config->save();
+    $this->enablePageCaching();
 
     $settings['settings']['omit_vary_cookie'] = (object) [
       'value' => TRUE,
@@ -420,15 +444,15 @@ public function testPageCacheWithoutVaryCookie() {
 
     // Fill the cache.
     $this->drupalGet('');
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Page was not cached.');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was not cached.');
     $this->assertTrue(strpos($this->drupalGetHeader('Vary'), 'Cookie') === FALSE, 'Vary: Cookie header was not sent.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public', 'Cache-Control header was sent.');
+    $this->assertEquals('max-age=300, public', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent.');
 
     // Check cache.
     $this->drupalGet('');
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was cached.');
     $this->assertTrue(strpos($this->drupalGetHeader('Vary'), 'Cookie') === FALSE, 'Vary: Cookie header was not sent.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public', 'Cache-Control header was sent.');
+    $this->assertEquals('max-age=300, public', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent.');
   }
 
   /**
@@ -436,16 +460,15 @@ public function testPageCacheWithoutVaryCookie() {
    */
   public function testFormImmutability() {
     // Install the module that provides the test form.
-    $this->container->get('module_installer')
-      ->install(['page_cache_form_test']);
+    \Drupal::service('module_installer')->install(['page_cache_form_test']);
     // Uninstall the page_cache module to verify that form is immutable
     // regardless of the internal page cache module.
-    $this->container->get('module_installer')->uninstall(['page_cache']);
+    \Drupal::service('module_installer')->uninstall(['page_cache']);
     \Drupal::service('router.builder')->rebuild();
 
     $this->drupalGet('page_cache_form_test_immutability');
 
-    $this->assertText("Immutable: TRUE", "Form is immutable.");
+    $this->assertTextHelper("Immutable: TRUE", FALSE);
 
     // The immutable flag is set unconditionally by system_form_alter(), set
     // a flag to tell page_cache_form_test_module_implements_alter() to disable
@@ -456,7 +479,7 @@ public function testFormImmutability() {
 
     $this->drupalGet('page_cache_form_test_immutability');
 
-    $this->assertText("Immutable: FALSE", "Form is not immutable,");
+    $this->assertTextHelper("Immutable: FALSE", FALSE);
   }
 
   /**
@@ -467,44 +490,41 @@ public function testFormImmutability() {
    * CacheableResponseInterface.
    */
   public function testCacheableResponseResponses() {
-    $config = $this->config('system.performance');
-    $config->set('cache.page.max_age', 300);
-    $config->save();
+    $this->enablePageCaching();
 
     // GET a URL, which would be marked as a cache miss if it were cacheable.
     $this->drupalGet('/system-test/respond-reponse');
     $this->assertFalse($this->drupalGetHeader('X-Drupal-Cache'), 'Drupal page cache header not found.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'must-revalidate, no-cache, private', 'Cache-Control header was sent');
+    $this->assertEquals('must-revalidate, no-cache, private', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent');
 
     // GET it again, verify it's still not cached.
     $this->drupalGet('/system-test/respond-reponse');
     $this->assertFalse($this->drupalGetHeader('X-Drupal-Cache'), 'Drupal page cache header not found.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'must-revalidate, no-cache, private', 'Cache-Control header was sent');
+    $this->assertEquals('must-revalidate, no-cache, private', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent');
 
     // GET a URL, which would be marked as a cache miss if it were cacheable.
     $this->drupalGet('/system-test/respond-public-response');
     $this->assertFalse($this->drupalGetHeader('X-Drupal-Cache'), 'Drupal page cache header not found.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=60, public', 'Cache-Control header was sent');
+    $this->assertEquals('max-age=60, public', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent');
 
     // GET it again, verify it's still not cached.
     $this->drupalGet('/system-test/respond-public-response');
     $this->assertFalse($this->drupalGetHeader('X-Drupal-Cache'), 'Drupal page cache header not found.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=60, public', 'Cache-Control header was sent');
+    $this->assertEquals('max-age=60, public', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent');
 
     // GET a URL, which should be marked as a cache miss.
     $this->drupalGet('/system-test/respond-cacheable-reponse');
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Page was not cached.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public', 'Cache-Control header was sent.');
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was not cached.');
+    $this->assertEquals('max-age=300, public', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent.');
 
     // GET it again, it should now be a cache hit.
     $this->drupalGet('/system-test/respond-cacheable-reponse');
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
-    $this->assertEqual($this->drupalGetHeader('Cache-Control'), 'max-age=300, public', 'Cache-Control header was sent.');
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was cached.');
+    $this->assertEquals('max-age=300, public', $this->drupalGetHeader('Cache-Control'), 'Cache-Control header was sent.');
 
     // Uninstall page cache. This should flush all caches so the next call to a
     // previously cached page should be a miss now.
-    $this->container->get('module_installer')
-      ->uninstall(['page_cache']);
+    \Drupal::service('module_installer')->uninstall(['page_cache']);
 
     // GET a URL that was cached by Page Cache before, it should not be now.
     $this->drupalGet('/respond-cacheable-reponse');
@@ -515,27 +535,29 @@ public function testCacheableResponseResponses() {
    * Tests that HEAD requests are treated the same as GET requests.
    */
   public function testHead() {
+    /** @var \GuzzleHttp\ClientInterface $client */
+    $client = $this->getSession()->getDriver()->getClient()->getClient();
     // GET, then HEAD.
     $url_a = $this->buildUrl('system-test/set-header', ['query' => ['name' => 'Foo', 'value' => 'bar']]);
-    $response_body = $this->curlExec([CURLOPT_HTTPGET => TRUE, CURLOPT_URL => $url_a, CURLOPT_CUSTOMREQUEST => 'GET', CURLOPT_NOBODY => FALSE]);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Page was not cached.');
-    $this->assertEqual($this->drupalGetHeader('Foo'), 'bar', 'Custom header was sent.');
-    $this->assertEqual('The following header was set: <em class="placeholder">Foo</em>: <em class="placeholder">bar</em>', $response_body);
-    $response_body = $this->curlExec([CURLOPT_HTTPGET => FALSE, CURLOPT_URL => $url_a, CURLOPT_CUSTOMREQUEST => 'HEAD', CURLOPT_NOBODY => FALSE]);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
-    $this->assertEqual($this->drupalGetHeader('Foo'), 'bar', 'Custom header was sent.');
-    $this->assertEqual('', $response_body);
+    $response_body = $this->drupalGet($url_a);
+    $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was not cached.');
+    $this->assertEquals('bar', $this->drupalGetHeader('Foo'), 'Custom header was sent.');
+    $this->assertEquals('The following header was set: <em class="placeholder">Foo</em>: <em class="placeholder">bar</em>', $response_body);
+    $response = $client->request('HEAD', $url_a);
+    $this->assertEquals('HIT', $response->getHeaderLine('X-Drupal-Cache'), 'Page was cached.');
+    $this->assertEquals('bar', $response->getHeaderLine('Foo'), 'Custom header was sent.');
+    $this->assertEquals('', $response->getBody()->getContents());
 
     // HEAD, then GET.
     $url_b = $this->buildUrl('system-test/set-header', ['query' => ['name' => 'Foo', 'value' => 'baz']]);
-    $response_body = $this->curlExec([CURLOPT_HTTPGET => FALSE, CURLOPT_URL => $url_b, CURLOPT_CUSTOMREQUEST => 'HEAD', CURLOPT_NOBODY => FALSE]);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', 'Page was not cached.');
-    $this->assertEqual($this->drupalGetHeader('Foo'), 'baz', 'Custom header was sent.');
-    $this->assertEqual('', $response_body);
-    $response_body = $this->curlExec([CURLOPT_HTTPGET => TRUE, CURLOPT_URL => $url_b, CURLOPT_CUSTOMREQUEST => 'GET', CURLOPT_NOBODY => FALSE]);
-    $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', 'Page was cached.');
-    $this->assertEqual($this->drupalGetHeader('Foo'), 'baz', 'Custom header was sent.');
-    $this->assertEqual('The following header was set: <em class="placeholder">Foo</em>: <em class="placeholder">baz</em>', $response_body);
+    $response = $client->request('HEAD', $url_b);
+    $this->assertEquals('MISS', $response->getHeaderLine('X-Drupal-Cache'), 'Page was not cached.');
+    $this->assertEquals('baz', $response->getHeaderLine('Foo'), 'Custom header was sent.');
+    $this->assertEquals('', $response->getBody()->getContents());
+    $response = $this->drupalGet($url_b);
+    $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), 'Page was cached.');
+    $this->assertEquals('baz', $this->drupalGetHeader('Foo'), 'Custom header was sent.');
+    $this->assertEquals('The following header was set: <em class="placeholder">Foo</em>: <em class="placeholder">baz</em>', $response);
   }
 
   /**
@@ -553,10 +575,6 @@ public function testNoUrlNormalization() {
         $url . '?z=z&a=a',
         $url . '?a=a&z=z',
       ],
-      [
-        $url . '?',
-        $url . '',
-      ],
       [
         $url . '?a=b+c',
         $url . '?a=b%20c',
@@ -567,14 +585,14 @@ public function testNoUrlNormalization() {
 
       // Initialize cache on raw URL.
       $this->drupalGet($url_raw);
-      $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
+      $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'));
       // Ensure cache was set.
       $this->drupalGet($url_raw);
-      $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'HIT', "Cache was set for {$url_raw} URL.");
+      $this->assertEquals('HIT', $this->drupalGetHeader('X-Drupal-Cache'), "Cache was set for {$url_raw} URL.");
 
       // Check if the normalized URL is not cached.
       $this->drupalGet($url_normalized);
-      $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS', "Cache is missing for {$url_normalized} URL.");
+      $this->assertEquals('MISS', $this->drupalGetHeader('X-Drupal-Cache'), "Cache is missing for {$url_normalized} URL.");
     }
   }