Bug 1663283 - Fix printing of nested iframes. r=smaug, a=RyanVM

Cloning of the nested documents should be recursive, I am dum dum. Differential Revision: https://phabricator.services.mozilla.com/D89313

Bug 1663283 - Fix printing of nested iframes. r=smaug, a=RyanVM
Cloning of the nested documents should be recursive, I am dum dum. Differential Revision: https://phabricator.services.mozilla.com/D89313
196a43c4 · Emilio Cobos Álvarez · 3222cb94 · 196a43c4 · 196a43c4 · 196a43c4
Commit 196a43c4 authored Sep 06, 2020 by Emilio Cobos Álvarez
--- a/dom/base/nsGlobalWindowOuter.cpp
+++ b/dom/base/nsGlobalWindowOuter.cpp
@@ -5262,6 +5262,37 @@ void nsGlobalWindowOuter::PrintOuter(ErrorResult& aError) {
 #endif
 }

+// Returns whether there's any print callback.
+static bool BuildNestedClones(Document& aJustClonedDoc) {
+  bool hasPrintCallbacks = aJustClonedDoc.HasPrintCallbacks();
+  auto pendingFrameClones = aJustClonedDoc.TakePendingFrameStaticClones();
+  for (const auto& clone : pendingFrameClones) {
+    RefPtr<Element> element = do_QueryObject(clone.mElement);
+    RefPtr<nsFrameLoader> frameLoader =
+        nsFrameLoader::Create(element, /* aNetworkCreated */ false);
+
+    if (NS_WARN_IF(!frameLoader)) {
+      continue;
+    }
+
+    clone.mElement->SetFrameLoader(frameLoader);
+
+    nsCOMPtr<nsIDocShell> docshell;
+    RefPtr<Document> doc;
+    nsresult rv = frameLoader->FinishStaticClone(clone.mStaticCloneOf,
+                                                 getter_AddRefs(docshell),
+                                                 getter_AddRefs(doc));
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      continue;
+    }
+
+    if (doc) {
+      hasPrintCallbacks |= BuildNestedClones(*doc);
+    }
+  }
+  return hasPrintCallbacks;
+}
+
 Nullable<WindowProxyHolder> nsGlobalWindowOuter::Print(
    nsIPrintSettings* aPrintSettings, nsIWebProgressListener* aListener,
    nsIDocShell* aDocShellToCloneInto, IsPreview aIsPreview,
@@ -5388,8 +5419,6 @@ Nullable<WindowProxyHolder> nsGlobalWindowOuter::Print(
        return nullptr;
      }

-      hasPrintCallbacks |= clone->HasPrintCallbacks();
-
      // Do this now so that we get a script handling object, and thus can
      // create our clones.
      aError = cv->SetDocument(clone);
@@ -5397,29 +5426,7 @@ Nullable<WindowProxyHolder> nsGlobalWindowOuter::Print(
        return nullptr;
      }

-      auto pendingFrameClones = clone->TakePendingFrameStaticClones();
-      for (const auto& clone : pendingFrameClones) {
-        RefPtr<Element> element = do_QueryObject(clone.mElement);
-        RefPtr<nsFrameLoader> frameLoader =
-            nsFrameLoader::Create(element, /* aNetworkCreated */ false);
-
-        if (NS_WARN_IF(!frameLoader)) {
-          continue;
-        }
-
-        clone.mElement->SetFrameLoader(frameLoader);
-
-        nsCOMPtr<nsIDocShell> docshell;
-        RefPtr<Document> doc;
-        nsresult rv = frameLoader->FinishStaticClone(clone.mStaticCloneOf,
-                                                     getter_AddRefs(docshell),
-                                                     getter_AddRefs(doc));
-        if (NS_WARN_IF(NS_FAILED(rv))) {
-          continue;
-        }
-
-        hasPrintCallbacks |= doc && doc->HasPrintCallbacks();
-      }
+      hasPrintCallbacks |= BuildNestedClones(*clone);
    }
  }


--- a/testing/web-platform/tests/html/browsers/windows/iframe-nested-print-ref.html
+++ b/testing/web-platform/tests/html/browsers/windows/iframe-nested-print-ref.html
+<!doctype html>
+<style>
+  body { margin: 0 }
+  p {
+    /* 2 times the default margin of <body>, to account for the doubly-nested document */
+    margin: 16px;
+  }
+</style>
+<p>PASS
--- a/testing/web-platform/tests/html/browsers/windows/iframe-nested-print.html
+++ b/testing/web-platform/tests/html/browsers/windows/iframe-nested-print.html
+<!doctype html>
+<link rel=match href="iframe-nested-print-ref.html">
+<style>
+  body { margin: 0 }
+</style>
+<iframe frameborder=0 scrolling=no srcdoc="<iframe scrolling=no frameborder=0 srcdoc='PASS'></iframe>"></iframe>