From 06a3ca734e0dea262c420d43994e9990830f2321 Mon Sep 17 00:00:00 2001
From: Timothy Flynn <trflynn89@pm.me>
Date: Thu, 4 Apr 2024 13:21:50 -0400
Subject: [PATCH] LibWeb: Handle changes to an input element's "multiple"
 attribute

Update the shadow tree so that the attribute is reflected on the page.
---
 Tests/LibWeb/Layout/expected/input-file.txt   | 26 +++++++++++++++++++
 Tests/LibWeb/Layout/input/input-file.html     |  7 +++++
 .../LibWeb/HTML/HTMLInputElement.cpp          |  2 ++
 3 files changed, 35 insertions(+)
diff --git a/Tests/LibWeb/Layout/expected/input-file.txt b/Tests/LibWeb/Layout/expected/input-file.txt
index 97611b25eaa..5b8a2a4c181 100644
--- a/Tests/LibWeb/Layout/expected/input-file.txt
+++ b/Tests/LibWeb/Layout/expected/input-file.txt
@@ -5,6 +5,9 @@ Viewport <#document> at (0,0) content-size 800x600 children: not-inline
       frag 1 from TextNode start: 0, length: 1, rect: [245,8 8x17] baseline: 13.296875
           " "
       frag 2 from BlockContainer start: 0, length: 0, rect: [253,8 255.34375x21] baseline: 13.296875
+      frag 3 from TextNode start: 0, length: 1, rect: [508,8 8x17] baseline: 13.296875
+          " "
+      frag 4 from BlockContainer start: 0, length: 0, rect: [516,8 255.34375x21] baseline: 13.296875
       BlockContainer <input> at (8,8) content-size 236.65625x21 inline-block [BFC] children: inline
         frag 0 from BlockContainer start: 0, length: 0, rect: [13,10 94.375x17] baseline: 13.296875
         frag 1 from Label start: 0, length: 0, rect: [116,8 128.28125x17] baseline: 13.296875
@@ -33,6 +36,21 @@ Viewport <#document> at (0,0) content-size 800x600 children: not-inline
               "No files selected."
           TextNode <#text>
       TextNode <#text>
+      BlockContainer <input#multiple> at (516,8) content-size 255.34375x21 inline-block [BFC] children: inline
+        frag 0 from BlockContainer start: 0, length: 0, rect: [521,10 103.71875x17] baseline: 13.296875
+        frag 1 from Label start: 0, length: 0, rect: [634,8 137.625x17] baseline: 13.296875
+        BlockContainer <button> at (521,10) content-size 103.71875x17 inline-block [BFC] children: not-inline
+          BlockContainer <(anonymous)> at (521,10) content-size 103.71875x17 flex-container(column) [FFC] children: not-inline
+            BlockContainer <(anonymous)> at (521,10) content-size 103.71875x17 flex-item [BFC] children: inline
+              frag 0 from TextNode start: 0, length: 15, rect: [521,10 103.71875x17] baseline: 13.296875
+                  "Select files..."
+              TextNode <#text>
+        Label <label> at (634,8) content-size 137.625x17 inline-block [BFC] children: inline
+          frag 0 from TextNode start: 0, length: 18, rect: [634,8 137.625x17] baseline: 13.296875
+              "No files selected."
+          TextNode <#text>
+      TextNode <#text>
+      TextNode <#text>
 
 ViewportPaintable (Viewport<#document>) [0,0 800x600]
   PaintableWithLines (BlockContainer<HTML>) [0,0 800x600]
@@ -52,3 +70,11 @@ ViewportPaintable (Viewport<#document>) [0,0 800x600]
               TextPaintable (TextNode<#text>)
         PaintableWithLines (Label<LABEL>) [367,8 141.625x17]
           TextPaintable (TextNode<#text>)
+      TextPaintable (TextNode<#text>)
+      PaintableWithLines (BlockContainer<INPUT>#multiple) [516,8 255.34375x21] overflow: [516,8 255.625x21]
+        PaintableWithLines (BlockContainer<BUTTON>) [516,8 113.71875x21]
+          PaintableWithLines (BlockContainer(anonymous)) [521,10 103.71875x17]
+            PaintableWithLines (BlockContainer(anonymous)) [521,10 103.71875x17]
+              TextPaintable (TextNode<#text>)
+        PaintableWithLines (Label<LABEL>) [630,8 141.625x17]
+          TextPaintable (TextNode<#text>)
diff --git a/Tests/LibWeb/Layout/input/input-file.html b/Tests/LibWeb/Layout/input/input-file.html
index 5bd152f04d7..3a8a8eb6652 100644
--- a/Tests/LibWeb/Layout/input/input-file.html
+++ b/Tests/LibWeb/Layout/input/input-file.html
@@ -1,2 +1,9 @@
 <input type="file" />
 <input type="file" multiple />
+<input id="multiple" type="file" />
+<script type="text/javascript">
+    document.addEventListener("DOMContentLoaded", () => {
+        let input = document.querySelector("#multiple");
+        input.multiple = true;
+    });
+</script>
diff --git a/Userland/Libraries/LibWeb/HTML/HTMLInputElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLInputElement.cpp
index 67d89e63d3a..a9cff20b78e 100644
--- a/Userland/Libraries/LibWeb/HTML/HTMLInputElement.cpp
+++ b/Userland/Libraries/LibWeb/HTML/HTMLInputElement.cpp
@@ -1098,6 +1098,8 @@ void HTMLInputElement::form_associated_element_attribute_changed(FlyString const
             did_update_alt_text(verify_cast<Layout::ImageBox>(*layout_node()));
     } else if (name == HTML::AttributeNames::maxlength) {
         handle_maxlength_attribute();
+    } else if (name == HTML::AttributeNames::multiple) {
+        update_shadow_tree();
     }
 }
 
