1 files changed, 141 insertions, 0 deletions
diff --git a/layout/generic/DetailsFrame.cpp b/layout/generic/DetailsFrame.cpp
new file mode 100644
index 0000000000..5c62ed5a31
--- /dev/null
+++ b/layout/generic/DetailsFrame.cpp
@@ -0,0 +1,141 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "DetailsFrame.h"
+
+#include "mozilla/Attributes.h"
+#include "mozilla/PresShell.h"
+#include "mozilla/dom/HTMLDetailsElement.h"
+#include "mozilla/dom/HTMLSummaryElement.h"
+#include "nsContentUtils.h"
+#include "nsPlaceholderFrame.h"
+#include "nsTextNode.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+NS_IMPL_FRAMEARENA_HELPERS(DetailsFrame)
+
+NS_QUERYFRAME_HEAD(DetailsFrame)
+  NS_QUERYFRAME_ENTRY(DetailsFrame)
+  NS_QUERYFRAME_ENTRY(nsIAnonymousContentCreator)
+NS_QUERYFRAME_TAIL_INHERITING(nsBlockFrame)
+
+nsBlockFrame* NS_NewDetailsFrame(PresShell* aPresShell, ComputedStyle* aStyle) {
+  return new (aPresShell) DetailsFrame(aStyle, aPresShell->GetPresContext());
+}
+
+namespace mozilla {
+
+DetailsFrame::DetailsFrame(ComputedStyle* aStyle, nsPresContext* aPresContext)
+    : nsBlockFrame(aStyle, aPresContext, kClassID) {}
+
+DetailsFrame::~DetailsFrame() = default;
+
+void DetailsFrame::SetInitialChildList(ChildListID aListID,
+                                       nsFrameList& aChildList) {
+#ifdef DEBUG
+  if (aListID == kPrincipalList) {
+    CheckValidMainSummary(aChildList);
+  }
+#endif
+
+  nsBlockFrame::SetInitialChildList(aListID, aChildList);
+}
+
+#ifdef DEBUG
+bool DetailsFrame::CheckValidMainSummary(const nsFrameList& aFrameList) const {
+  for (nsIFrame* child : aFrameList) {
+    if (child->IsGeneratedContentFrame()) {
+      continue;
+    }
+    HTMLSummaryElement* summary =
+        HTMLSummaryElement::FromNode(child->GetContent());
+    if (child == aFrameList.FirstChild()) {
+      if (summary && summary->IsMainSummary()) {
+        return true;
+      } else if (child->GetContent() == GetContent()) {
+        // The child frame's content is the same as our content, which means
+        // it's a kind of wrapper frame. Descend into its child list to find
+        // main summary.
+        if (CheckValidMainSummary(child->PrincipalChildList())) {
+          return true;
+        }
+      }
+    } else {
+      NS_ASSERTION(!summary || !summary->IsMainSummary(),
+                   "Rest of the children are either not summary element "
+                   "or are not the main summary!");
+    }
+  }
+  return false;
+}
+#endif
+
+void DetailsFrame::DestroyFrom(nsIFrame* aDestructRoot,
+                               PostDestroyData& aPostDestroyData) {
+  aPostDestroyData.AddAnonymousContent(mDefaultSummary.forget());
+  nsBlockFrame::DestroyFrom(aDestructRoot, aPostDestroyData);
+}
+
+nsresult DetailsFrame::CreateAnonymousContent(
+    nsTArray<ContentInfo>& aElements) {
+  auto* details = HTMLDetailsElement::FromNode(GetContent());
+  if (details->GetFirstSummary()) {
+    return NS_OK;
+  }
+
+  // The <details> element lacks any direct <summary> child. Create a default
+  // <summary> element as an anonymous content.
+  nsNodeInfoManager* nodeInfoManager =
+      GetContent()->NodeInfo()->NodeInfoManager();
+
+  RefPtr<NodeInfo> nodeInfo = nodeInfoManager->GetNodeInfo(
+      nsGkAtoms::summary, nullptr, kNameSpaceID_XHTML, nsINode::ELEMENT_NODE);
+  mDefaultSummary = new (nodeInfoManager) HTMLSummaryElement(nodeInfo.forget());
+
+  nsAutoString defaultSummaryText;
+  nsContentUtils::GetMaybeLocalizedString(
+      nsContentUtils::eFORMS_PROPERTIES, "DefaultSummary",
+      GetContent()->OwnerDoc(), defaultSummaryText);
+  RefPtr<nsTextNode> description =
+      new (nodeInfoManager) nsTextNode(nodeInfoManager);
+  description->SetText(defaultSummaryText, false);
+  mDefaultSummary->AppendChildTo(description, false);
+
+  aElements.AppendElement(mDefaultSummary);
+
+  return NS_OK;
+}
+
+void DetailsFrame::AppendAnonymousContentTo(nsTArray<nsIContent*>& aElements,
+                                            uint32_t aFilter) {
+  if (mDefaultSummary) {
+    aElements.AppendElement(mDefaultSummary);
+  }
+}
+
+bool DetailsFrame::HasMainSummaryFrame(nsIFrame* aSummaryFrame) {
+  const ChildListIDs flowLists = {kPrincipalList, kOverflowList};
+  for (nsIFrame* frag = this; frag; frag = frag->GetNextInFlow()) {
+    for (const auto& [list, listID] : frag->ChildLists()) {
+      if (!flowLists.contains(listID)) {
+        continue;
+      }
+      for (nsIFrame* child : list) {
+        child = nsPlaceholderFrame::GetRealFrameFor(child);
+        // We skip any non-primary frames such as a list-style-position:inside
+        // bullet frame for the <details> itself.
+        if (!child->IsGeneratedContentFrame()) {
+          return aSummaryFrame == child;
+        }
+      }
+    }
+  }
+  return false;
+}
+
+}  // namespace mozilla