From f638f84185938c74a47f5691e8d7c5e1d4dca07c Mon Sep 17 00:00:00 2001
From: Luke Wilde <lukew@serenityos.org>
Date: Fri, 15 Nov 2024 16:17:10 +0000
Subject: [PATCH] LibWeb: Make default document readiness be "complete"

This is required by mini Cloudflare invisible challenges, as it will
only run if the readyState is not "loading". If it is "loading", then
it waits for readystatechange to check that it's not "loading" anymore.

Initial about:blank iframes do not go through the full navigation and
thus don't go through HTMLParser::the_end, which sets the ready state
to something other than "loading". Therefore, the challenge would never
run, as readyState would never change.

Seen on https://discord.com/login
---
 Libraries/LibWeb/DOM/Document.h                    |  8 +++++++-
 .../document-readyState-is-initially-complete.txt  |  5 +++++
 .../LibWeb/Text/input/HTML/Window-postMessage.html | 14 ++------------
 .../document-readyState-is-initially-complete.html | 14 ++++++++++++++
 4 files changed, 28 insertions(+), 13 deletions(-)
 create mode 100644 Tests/LibWeb/Text/expected/HTML/document-readyState-is-initially-complete.txt
 create mode 100644 Tests/LibWeb/Text/input/HTML/document-readyState-is-initially-complete.html

diff --git a/Libraries/LibWeb/DOM/Document.h b/Libraries/LibWeb/DOM/Document.h
index c8a882e1003..3c11a21b209 100644
--- a/Libraries/LibWeb/DOM/Document.h
+++ b/Libraries/LibWeb/DOM/Document.h
@@ -823,7 +823,13 @@ private:
     GC::Ptr<Document> m_associated_inert_template_document;
     GC::Ptr<Document> m_appropriate_template_contents_owner_document;
 
-    HTML::DocumentReadyState m_readiness { HTML::DocumentReadyState::Loading };
+    // https://html.spec.whatwg.org/multipage/dom.html#current-document-readiness
+    // Each Document has a current document readiness, a string, initially "complete".
+    // Spec Note: For Document objects created via the create and initialize a Document object algorithm, this will be
+    //            immediately reset to "loading" before any script can observe the value of document.readyState.
+    //            This default applies to other cases such as initial about:blank Documents or Documents without a
+    //            browsing context.
+    HTML::DocumentReadyState m_readiness { HTML::DocumentReadyState::Complete };
     String m_content_type { "application/xml"_string };
     Optional<String> m_pragma_set_default_language;
     Optional<String> m_encoding;
diff --git a/Tests/LibWeb/Text/expected/HTML/document-readyState-is-initially-complete.txt b/Tests/LibWeb/Text/expected/HTML/document-readyState-is-initially-complete.txt
new file mode 100644
index 00000000000..1475ac05792
--- /dev/null
+++ b/Tests/LibWeb/Text/expected/HTML/document-readyState-is-initially-complete.txt
@@ -0,0 +1,5 @@
+readyState of 'new Document()' should be 'complete': 'complete'
+readyState of 'document.implementation.createHTMLDocument()' should be 'complete': 'complete'
+readyState of 'document.implementation.createDocument()' should be 'complete': 'complete'
+FIXME: readyState of 'new DOMParser().parseFromString('', 'text/html')' should be 'complete': 'interactive'
+readyState of 'iframe.contentDocument' of initial about:blank iframe should be 'complete': 'complete'
diff --git a/Tests/LibWeb/Text/input/HTML/Window-postMessage.html b/Tests/LibWeb/Text/input/HTML/Window-postMessage.html
index 153eaa0952e..ec8f9608d6d 100644
--- a/Tests/LibWeb/Text/input/HTML/Window-postMessage.html
+++ b/Tests/LibWeb/Text/input/HTML/Window-postMessage.html
@@ -127,21 +127,11 @@
         globalThis.doneCallback = done;
 
         const blobIframeLoadPromise = new Promise(resolve => {
-            if (blobIframe.contentDocument.readyState === "complete") {
-                resolve();
-            }
-            else {
-                blobIframe.onload = () => resolve();
-            }
+            blobIframe.onload = () => resolve();
         });
 
         const srcdocIframeLoadPromise = new Promise(resolve => {
-            if (iframe.contentDocument.readyState === "complete") {
-                resolve()
-            }
-            else {
-                iframe.onload = () => resolve();
-            }
+            iframe.onload = () => resolve();
         });
 
         Promise.all([blobIframeLoadPromise, srcdocIframeLoadPromise]).then(() => {
diff --git a/Tests/LibWeb/Text/input/HTML/document-readyState-is-initially-complete.html b/Tests/LibWeb/Text/input/HTML/document-readyState-is-initially-complete.html
new file mode 100644
index 00000000000..3f5b996338a
--- /dev/null
+++ b/Tests/LibWeb/Text/input/HTML/document-readyState-is-initially-complete.html
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<script src="../include.js"></script>
+<script>
+    test(() => {
+        println(`readyState of 'new Document()' should be 'complete': '${new Document().readyState}'`);
+        println(`readyState of 'document.implementation.createHTMLDocument()' should be 'complete': '${document.implementation.createHTMLDocument().readyState}'`);
+        println(`readyState of 'document.implementation.createDocument()' should be 'complete': '${document.implementation.createDocument('http://www.w3.org/1999/xhtml', '').readyState}'`);
+        println(`FIXME: readyState of 'new DOMParser().parseFromString('', 'text/html')' should be 'complete': '${new DOMParser().parseFromString('', 'text/html').readyState}'`);
+
+        const iframe = document.createElement("iframe");
+        document.body.appendChild(iframe);
+        println(`readyState of 'iframe.contentDocument' of initial about:blank iframe should be 'complete': '${iframe.contentDocument.readyState}'`);
+    });
+</script>