HttpKernelUiHelperTrait::drupalGet() doesn't work with result of ::getUrl()

> I have a hunch that maybef the special handling I'd added to the browser at the symfony level was needed after all.

The bit I mean is commit 40f2cc07edabd8cf86f67deb8cb25274a4ddb7af in branch 3390193-add-drupalget-with-mink-to-kerneltestbase in the fork for #3390193: Add a drupalGet() method to KernelTestBase.

This added a custom browser class whose job was to convert all URLs to relative:

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\TestTools\HttpKernel;
+
+use Symfony\Component\HttpKernel\HttpKernelBrowser;
+
+/**
+ * Browserkit client for use in kernel tests.
+ *
+ * This overrides getAbsoluteUri() to skip the conversion from a relative URI to
+ * an absolute URI. We are using this with the HTTP kernel and that needs a
+ * relative URI.
+ */
+class KernelTestHttpKernelBrowser extends HttpKernelBrowser {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getAbsoluteUri(string $uri): string {
+    // Preserve the given relative URI.
+    return $uri;
+  }
+
+}

I don't remember the details, but what I **think** this meant was that we let Mink handle converting any URL we passed into its browser, and then at the end we make it into something that the HTTP kernel can work with.

I'm wondering whether with this, we fix this bug and also we no longer need the special handling for anchor links.

Yes, restoring that makes this work:

$this->drupalGet($this->getUrl());

Hmm but it doesn't work with relative query links.

And HttpKernelBrowser::getAbsoluteUri() is doing weird stuff to the URLs in that scenario (#3589626: clickLink in kernel tests erroneously prefixes some paths with / didn't add a test for it)

Making a draft MR with some of my work so far.

Overriding getAbsoluteUri() fixes one thing, but breaks another!!!

I've also tried stripping the host from the URL using the PHP 8.5 Uri\Rfc3986\Uri class like this:

  protected function getAbsoluteUri(string $uri): string {
    dump($uri);

    $uri = parent::getAbsoluteUri($uri);
    dump($uri);

    $uri_object = new Uri($uri);

    $uri_object = $uri_object->withScheme(NULL)->withHost(NULL);

    $uri = $uri_object->toRawString();
    dump($uri);

    // dump($uri);
    return $uri;

but in some calls, the call to parent::getAbsoluteUri() is doing WEIRD STUFF to a relative URL.

Actually, if we're doing to use Uri\Rfc3986\Uri, then maybe we should use it to manipulate getUrl() to return a path (eg. '/my/page'), that way the manipulation is targeted only where it needs to be done, instead of on every drupalGet() call.

That works!

True, but then we'd be diverging totally from the getUrl() in browser tests.

Ok with getUrlObject().
But getUrlString() on kernel tests has no purpose as an absolute URL

Also, what kind of Url object? Drupal URL or PSR URL?