From 9eb38ce79c2828f8cc280d694aec71dc1c5894ac Mon Sep 17 00:00:00 2001
From: Timothy Flynn <trflynn89@pm.me>
Date: Thu, 14 Mar 2024 10:33:15 -0400
Subject: [PATCH] LibWeb: Update the <textarea> shadow DOM after reseting its
 form owner

This generally happens after a form is submitted. We need to update the
text node in the shadow DOM to actually display the reset value.
---
 .../LibWeb/Layout/expected/textarea-reset.txt | 26 +++++++++++++++++++
 Tests/LibWeb/Layout/input/textarea-reset.html | 10 +++++++
 .../LibWeb/HTML/HTMLTextAreaElement.cpp       |  5 +++-
 3 files changed, 40 insertions(+), 1 deletion(-)
 create mode 100644 Tests/LibWeb/Layout/expected/textarea-reset.txt
 create mode 100644 Tests/LibWeb/Layout/input/textarea-reset.html
diff --git a/Tests/LibWeb/Layout/expected/textarea-reset.txt b/Tests/LibWeb/Layout/expected/textarea-reset.txt
new file mode 100644
index 00000000000..5f8f365afa6
--- /dev/null
+++ b/Tests/LibWeb/Layout/expected/textarea-reset.txt
@@ -0,0 +1,26 @@
+Viewport <#document> at (0,0) content-size 800x600 children: not-inline
+  BlockContainer <html> at (0,0) content-size 800x600 [BFC] children: not-inline
+    BlockContainer <body> at (8,8) content-size 784x34 children: not-inline
+      BlockContainer <form#form> at (8,8) content-size 784x34 children: inline
+        frag 0 from BlockContainer start: 0, length: 0, rect: [11,11 185.875x28] baseline: 13.296875
+        TextNode <#text>
+        BlockContainer <textarea#textarea> at (11,11) content-size 185.875x28 inline-block [BFC] children: not-inline
+          BlockContainer <div> at (11,11) content-size 185.875x17 children: not-inline
+            BlockContainer <div> at (11,11) content-size 185.875x17 children: inline
+              frag 0 from TextNode start: 0, length: 14, rect: [11,11 108.453125x17] baseline: 13.296875
+                  "Original value"
+              TextNode <#text>
+        TextNode <#text>
+      BlockContainer <(anonymous)> at (8,58) content-size 784x0 children: inline
+        TextNode <#text>
+        TextNode <#text>
+
+ViewportPaintable (Viewport<#document>) [0,0 800x600]
+  PaintableWithLines (BlockContainer<HTML>) [0,0 800x600]
+    PaintableWithLines (BlockContainer<BODY>) [8,8 784x34] overflow: [8,8 784x50]
+      PaintableWithLines (BlockContainer<FORM>#form) [8,8 784x34]
+        PaintableWithLines (BlockContainer<TEXTAREA>#textarea) [8,8 191.875x34]
+          PaintableWithLines (BlockContainer<DIV>) [11,11 185.875x17]
+            PaintableWithLines (BlockContainer<DIV>) [11,11 185.875x17]
+              TextPaintable (TextNode<#text>)
+      PaintableWithLines (BlockContainer(anonymous)) [8,58 784x0]
diff --git a/Tests/LibWeb/Layout/input/textarea-reset.html b/Tests/LibWeb/Layout/input/textarea-reset.html
new file mode 100644
index 00000000000..a5e1f578263
--- /dev/null
+++ b/Tests/LibWeb/Layout/input/textarea-reset.html
@@ -0,0 +1,10 @@
+<form id="form">
+    <textarea id="textarea">Original value</textarea>
+</form>
+<script type="text/javascript">
+    let textarea = document.getElementById("textarea");
+    textarea.value = "Modified value";
+
+    let form = document.getElementById("form");
+    form.reset();
+</script>
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLTextAreaElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLTextAreaElement.cpp
index c49bb17f064..1995b52ce3a 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLTextAreaElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLTextAreaElement.cpp
@@ -96,7 +96,10 @@ void HTMLTextAreaElement::reset_algorithm()
     // and set the raw value of element to its child text content.
     set_raw_value(child_text_content());
 
-    update_placeholder_visibility();
+    if (m_text_node) {
+        m_text_node->set_text_content(m_raw_value);
+        update_placeholder_visibility();
+    }
 }
 
 void HTMLTextAreaElement::form_associated_element_was_inserted()
