third_party/WebKit/Source/bindings/core/v8/ScriptSourceCode.cpp

// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "bindings/core/v8/ScriptSourceCode.h"

namespace blink {

ScriptSourceCode::ScriptSourceCode()
    : m_startPosition(TextPosition::minimumPosition()) {}

ScriptSourceCode::ScriptSourceCode(const String& source,
                                   const KURL& url,
                                   const TextPosition& startPosition)
    : m_source(source), m_url(url), m_startPosition(startPosition) {
  treatNullSourceAsEmpty();
  if (!m_url.isEmpty())
    m_url.removeFragmentIdentifier();
}

ScriptSourceCode::ScriptSourceCode(ScriptResource* resource)
    : m_source(resource->script()),
      m_resource(resource),
      m_startPosition(TextPosition::minimumPosition()) {
  treatNullSourceAsEmpty();
}

ScriptSourceCode::ScriptSourceCode(ScriptStreamer* streamer,
                                   ScriptResource* resource)
    : m_source(resource->script()),
      m_resource(resource),
      m_streamer(streamer),
      m_startPosition(TextPosition::minimumPosition()) {
  treatNullSourceAsEmpty();
}

ScriptSourceCode::~ScriptSourceCode() {}

void ScriptSourceCode::dispose() {
  m_source = String();
  m_resource = nullptr;
  m_streamer = nullptr;
  m_url = KURL();
}

DEFINE_TRACE(ScriptSourceCode) {
  visitor->trace(m_resource);
  visitor->trace(m_streamer);
}

const KURL& ScriptSourceCode::url() const {
  if (m_url.isEmpty() && m_resource) {
    m_url = m_resource->response().url();
    if (!m_url.isEmpty())
      m_url.removeFragmentIdentifier();
  }
  return m_url;
}

String ScriptSourceCode::sourceMapUrl() const {
  if (!m_resource)
    return String();
  const ResourceResponse& response = m_resource->response();
  String sourceMapUrl = response.httpHeaderField(HTTPNames::SourceMap);
  if (sourceMapUrl.isEmpty()) {
    // Try to get deprecated header.
    sourceMapUrl = response.httpHeaderField(HTTPNames::X_SourceMap);
  }
  return sourceMapUrl;
}

void ScriptSourceCode::treatNullSourceAsEmpty() {
  // ScriptSourceCode allows for the representation of the null/not-there-really
  // ScriptSourceCode value.  Encoded by way of a m_source.isNull() being true,
  // with the nullary constructor to be used to construct such a value.
  //
  // Should the other constructors be passed a null string, that is interpreted
  // as representing the empty script. Consequently, we need to disambiguate
  // between such null string occurrences.  Do that by converting the latter
  // case's null strings into empty ones.
  if (m_source.isNull())
    m_source = "";
}

}  // namespace blink