From 015148fcc37225f93dd0bd0d5913ec3e5acff2db Mon Sep 17 00:00:00 2001
From: FranklinDM <mrmineshafter17@gmail.com>
Date: Sat, 4 Mar 2023 19:17:22 +0800
Subject: [PATCH] Issue #2135 - Bug 1425864: Ensure printing documents which
 have shadow DOM works

---
 dom/base/ShadowRoot.cpp  | 17 +++++++++++++++++
 dom/base/ShadowRoot.h    |  5 +++++
 dom/base/nsNodeUtils.cpp | 27 +++++++++++++++++++++++++--
 3 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/dom/base/ShadowRoot.cpp b/dom/base/ShadowRoot.cpp
index 39859da4cf..e31b97262c 100644
--- a/dom/base/ShadowRoot.cpp
+++ b/dom/base/ShadowRoot.cpp
@@ -101,6 +101,23 @@ ShadowRoot::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
   return mozilla::dom::ShadowRootBinding::Wrap(aCx, this, aGivenProto);
 }
 
+void
+ShadowRoot::CloneInternalDataFrom(ShadowRoot* aOther)
+{
+  size_t sheetCount = aOther->SheetCount();
+  for (size_t i = 0; i < sheetCount; ++i) {
+    StyleSheet* sheet = aOther->SheetAt(i);
+    if (sheet && sheet->IsApplicable()) {
+      // TODO: Remove AsGecko() call once Stylo is removed.
+      RefPtr<CSSStyleSheet> clonedSheet =
+        sheet->AsGecko()->Clone(nullptr, nullptr, nullptr, nullptr);
+      if (clonedSheet) {
+        AppendStyleSheet(*clonedSheet);
+      }
+    }
+  }
+}
+
 ShadowRoot*
 ShadowRoot::FromNode(nsINode* aNode)
 {
diff --git a/dom/base/ShadowRoot.h b/dom/base/ShadowRoot.h
index 580099875d..e122a65ef1 100644
--- a/dom/base/ShadowRoot.h
+++ b/dom/base/ShadowRoot.h
@@ -64,6 +64,11 @@ public:
     return &DocumentOrShadowRoot::EnsureDOMStyleSheets();
   }
 
+  /**
+   * Clones internal state, for example stylesheets, of aOther to 'this'.
+   */
+  void CloneInternalDataFrom(ShadowRoot* aOther);
+
   /**
    * Distributes all the explicit children of the pool host to the content
    * insertion points in this ShadowRoot.
diff --git a/dom/base/nsNodeUtils.cpp b/dom/base/nsNodeUtils.cpp
index f1be693d2e..80a0f93247 100644
--- a/dom/base/nsNodeUtils.cpp
+++ b/dom/base/nsNodeUtils.cpp
@@ -653,8 +653,31 @@ nsNodeUtils::CloneAndAdopt(nsINode *aNode, bool aClone, bool aDeep,
     }
   }
 
-  if (aDeep && !aClone && aNode->IsElement()) {
-    if (ShadowRoot* shadowRoot = aNode->AsElement()->GetShadowRoot()) {
+  if (aDeep && aNode->IsElement()) {
+    ShadowRoot* shadowRoot = aNode->AsElement()->GetShadowRoot();
+    if (!shadowRoot) {
+      // Nothing to do here.
+    } else if (aClone && clone->OwnerDoc()->IsStaticDocument()) {
+      ShadowRootInit init;
+      init.mMode = shadowRoot->Mode();
+      RefPtr<ShadowRoot> newShadowRoot =
+        clone->AsElement()->AttachShadow(init, aError);
+      if (NS_WARN_IF(aError.Failed())) {
+        return nullptr;
+      }
+
+      newShadowRoot->CloneInternalDataFrom(shadowRoot);
+      for (nsIContent* originalChild = shadowRoot->GetFirstChild();
+           originalChild;
+           originalChild = originalChild->GetNextSibling()) {
+        nsCOMPtr<nsINode> child = CloneAndAdopt(originalChild, aClone, aDeep, nodeInfoManager,
+                                                aReparentScope, aNodesWithProperties, newShadowRoot,
+                                                aError);
+        if (NS_WARN_IF(aError.Failed())) {
+          return nullptr;
+        }
+      }
+    } else if (!aClone) {
       nsCOMPtr<nsINode> child = CloneAndAdopt(shadowRoot, aClone, aDeep, nodeInfoManager,
                                               aReparentScope, aNodesWithProperties, clone,
                                               aError);