chromium/src/third_party/blink/renderer/core/html/imports/html_import_state_resolver.cc

/*
 * Copyright (C) 2014 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 *
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 * in the documentation and/or other materials provided with the
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 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#include "third_party/blink/renderer/core/html/imports/html_import_state_resolver.h"

#include "third_party/blink/renderer/core/html/imports/html_import.h"
#include "third_party/blink/renderer/core/html/imports/html_import_child.h"
#include "third_party/blink/renderer/core/html/imports/html_import_loader.h"

namespace blink {

inline bool HTMLImportStateResolver::IsBlockingFollowers(HTMLImport* import) {
  if (!import->IsSync())
    return false;
  HTMLImportChild* child = ToHTMLImportChild(import);
  if (!child->Loader()->IsFirstImport(child))
    return false;
  return !import->GetState().IsReady();
}

inline bool HTMLImportStateResolver::ShouldBlockScriptExecution() const {
  // FIXME: Memoize to make this faster.
  for (HTMLImport* ancestor = import_; ancestor;
       ancestor = ancestor->Parent()) {
    for (HTMLImport* predecessor = ancestor->Previous(); predecessor;
         predecessor = predecessor->Previous()) {
      if (IsBlockingFollowers(predecessor))
        return true;
    }
  }

  for (HTMLImport* child = import_->FirstChild(); child;
       child = child->Next()) {
    if (IsBlockingFollowers(child))
      return true;
  }

  return false;
}

inline bool HTMLImportStateResolver::IsActive() const {
  return !import_->HasFinishedLoading();
}

HTMLImportState HTMLImportStateResolver::Resolve() const {
  if (ShouldBlockScriptExecution())
    return HTMLImportState(HTMLImportState::kBlockingScriptExecution);
  if (IsActive())
    return HTMLImportState(HTMLImportState::kActive);
  return HTMLImportState(HTMLImportState::kReady);
}

}  // namespace blink