Introduce Selection class

third_party/WebKit/Source/core/editing/SelectionTemplate.cpp

+// Copyright 2016 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 "core/editing/SelectionTemplate.h"
+
+#include "wtf/Assertions.h"
+#include <ostream>  // NOLINT
+
+namespace blink {
+
+template <typename Strategy>
+SelectionTemplate<Strategy>::SelectionTemplate(const SelectionTemplate& other)
+    : m_base(other.m_base),
+      m_extent(other.m_extent),
+      m_affinity(other.m_affinity),
+      m_granularity(other.m_granularity),
+      m_hasTrailingWhitespace(other.m_hasTrailingWhitespace),
+      m_isDirectional(other.m_isDirectional)
+#if DCHECK_IS_ON()
+      ,
+      m_domTreeVersion(other.m_domTreeVersion)
+#endif
+{
+  other.assertValid();
+  if (!m_hasTrailingWhitespace)
+    return;
+  DCHECK_EQ(m_granularity, WordGranularity) << *this;
+}
+
+template <typename Strategy>
+SelectionTemplate<Strategy>::SelectionTemplate() = default;
+
+template <typename Strategy>
+bool SelectionTemplate<Strategy>::operator==(
+    const SelectionTemplate& other) const {
+  assertValid();
+  other.assertValid();
+  if (isNone())
+    return other.isNone();
+  if (other.isNone())
+    return false;
+  DCHECK_EQ(m_base.document(), other.document()) << *this << ' ' << other;
+  return m_base == other.m_base && m_extent == other.m_extent &&
+         m_affinity == other.m_affinity &&
+         m_granularity == other.m_granularity &&
+         m_hasTrailingWhitespace == other.m_hasTrailingWhitespace &&
+         m_isDirectional == other.m_isDirectional;
+}
+
+template <typename Strategy>
+bool SelectionTemplate<Strategy>::operator!=(
+    const SelectionTemplate& other) const {
+  return !operator==(other);
+}
+
+template <typename Strategy>
+const PositionTemplate<Strategy>& SelectionTemplate<Strategy>::base() const {
+  assertValid();
+  DCHECK(!m_base.isOrphan()) << m_base;
+  return m_base;
+}
+
+template <typename Strategy>
+Document* SelectionTemplate<Strategy>::document() const {
+  assertValid();
+  return m_base.document();
+}
+
+template <typename Strategy>
+const PositionTemplate<Strategy>& SelectionTemplate<Strategy>::extent() const {
+  assertValid();
+  DCHECK(!m_extent.isOrphan()) << m_extent;
+  return m_extent;
+}
+
+template <typename Strategy>
+void SelectionTemplate<Strategy>::assertValidFor(
+    const Document& document) const {
+  assertValid();
+  if (m_base.isNull())
+    return;
+  DCHECK_EQ(m_base.document(), document) << *this;
+}
+
+#if DCHECK_IS_ON()
+template <typename Strategy>
+void SelectionTemplate<Strategy>::assertValid() const {
+  if (m_base.isNull())
+    return;
+  DCHECK_EQ(m_base.document()->domTreeVersion(), m_domTreeVersion) << *this;
+  DCHECK(!m_base.isOrphan()) << *this;
+  DCHECK(!m_extent.isOrphan()) << *this;
+}
+#else
+template <typename Strategy>
+void SelectionTemplate<Strategy>::assertValid() const {}
+#endif
+
+template <typename Strategy>
+void SelectionTemplate<Strategy>::printTo(std::ostream* ostream,
+                                          const char* type) const {
+  if (isNone()) {
+    *ostream << "()";
+    return;
+  }
+  *ostream << type << '(';
+#if DCHECK_IS_ON()
+  if (m_domTreeVersion != m_base.document()->domTreeVersion()) {
+    *ostream << "Dirty: " << m_domTreeVersion;
+    *ostream << " != " << m_base.document()->domTreeVersion() << ' ';
+  }
+#endif
+  *ostream << "base: " << m_base << ", extent: " << m_extent << ')';
+}
+
+std::ostream& operator<<(std::ostream& ostream,
+                         const SelectionInDOMTree& selection) {
+  selection.printTo(&ostream, "Selection");
+  return ostream;
+}
+
+std::ostream& operator<<(std::ostream& ostream,
+                         const SelectionInFlatTree& selection) {
+  selection.printTo(&ostream, "SelectionInFlatTree");
+  return ostream;
+}
+
+// --
+
+template <typename Strategy>
+SelectionTemplate<Strategy>::Builder::Builder(
+    const SelectionTemplate<Strategy>& selection)
+    : m_selection(selection) {}
+
+template <typename Strategy>
+SelectionTemplate<Strategy>::Builder::Builder() = default;
+
+template <typename Strategy>
+SelectionTemplate<Strategy> SelectionTemplate<Strategy>::Builder::build()
+    const {
+  return m_selection;

[yoichio, 2016/10/12 01:37:00]

DCHECK(m_selection.assertValid()) ?

[yosin_UTC9, 2016/10/12 03:39:02]

Good catch! Done.

+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::collapse(
+    const PositionTemplate<Strategy>& position) {
+  DCHECK(position.isConnected());
+  m_selection.m_base = position;
+  m_selection.m_extent = position;
+#if DCHECK_IS_ON()
+  m_selection.m_domTreeVersion = position.document()->domTreeVersion();
+#endif
+  return *this;
+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::collapse(
+    const PositionWithAffinityTemplate<Strategy>& positionWithAffinity) {
+  collapse(positionWithAffinity.position());
+  setAffinity(positionWithAffinity.affinity());
+  return *this;
+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::extend(
+    const PositionTemplate<Strategy>& position) {
+  DCHECK(position.isConnected());
+  DCHECK(m_selection.base().isConnected());
+  m_selection.assertValid();
+  m_selection.m_extent = position;
+  return *this;
+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::setAffinity(TextAffinity affinity) {
+  m_selection.m_affinity = affinity;
+  return *this;
+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::setBaseAndExtent(
+    const EphemeralRangeTemplate<Strategy>& range) {
+  if (range.isNull()) {

[yoichio, 2016/10/12 01:37:00]

Do we need this kind of resetting?

[yosin_UTC9, 2016/10/12 03:39:02]

Yes. There are usages in SelectionEditor::pdateCachedVisibleSelectionIfNeeded()
in http://crrev.com/1958093002

If we don't allow to pass (null, null) to setBaseAndExtent() we should write:

SelectionInFlatTree::Builder builder;
const PositionInFlatTree& base = toPositionInFlatTree(m_selection.base());
const PositionInFlatTree& extent = toPositionInFlatTree(m_selection.extent());
if (base.isNotNull()) {
  DCHECK(extent.isNotNull());
  builder.setBaseAndExtent(base, extent);
} else {
  DCHECK(extent.isNull()); // optional: we can omit but I prefer to have.
}

This leads callers to do more things. Setting both base/extent at once is normal
and common case if base/extent != null or base/extent == null.

Again, base == null && extent != null case denotes something wrong in caller.

+    m_selection.m_base = PositionTemplate<Strategy>();
+    m_selection.m_extent = PositionTemplate<Strategy>();
+#if DCHECK_IS_ON()
+    m_selection.m_domTreeVersion = 0;
+#endif
+    return *this;
+  }
+  return collapse(range.startPosition()).extend(range.endPosition());
+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::setBaseAndExtent(
+    const PositionTemplate<Strategy>& base,
+    const PositionTemplate<Strategy>& extent) {
+  if (base.isNull()) {

[yoichio, 2016/10/12 01:37:00]

ditto

[yosin_UTC9, 2016/10/12 03:39:02]

See a reply in EphemeralRange version of setBaseAndExtent.

+    DCHECK(extent.isNull()) << extent;
+    return setBaseAndExtent(EphemeralRangeTemplate<Strategy>());
+  }
+  DCHECK(extent.isNotNull());
+  return collapse(base).extend(extent);

[yosin_UTC9, 2016/10/12 03:39:02]

Note: |base| can be following to |extent|

+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::setBaseAndExtentDeprecated(
+    const PositionTemplate<Strategy>& base,
+    const PositionTemplate<Strategy>& extent) {
+  if (base.isNotNull() && extent.isNotNull()) {
+    return setBaseAndExtent(base, extent);
+  }
+  if (base.isNotNull())
+    return collapse(base);
+  if (extent.isNotNull())
+    return collapse(extent);
+  m_selection.m_base = PositionTemplate<Strategy>();
+  m_selection.m_extent = PositionTemplate<Strategy>();
+  return *this;
+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::setGranularity(
+    TextGranularity granularity) {
+  m_selection.m_granularity = granularity;
+  return *this;
+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::setHasTrailingWhitespace(
+    bool hasTrailingWhitespace) {
+  m_selection.m_hasTrailingWhitespace = hasTrailingWhitespace;
+  return *this;
+}
+
+template <typename Strategy>
+typename SelectionTemplate<Strategy>::Builder&
+SelectionTemplate<Strategy>::Builder::setIsDirectional(bool isDirectional) {
+  m_selection.m_isDirectional = isDirectional;
+  return *this;
+}
+
+template class CORE_TEMPLATE_EXPORT SelectionTemplate<EditingStrategy>;
+template class CORE_TEMPLATE_EXPORT
+    SelectionTemplate<EditingInFlatTreeStrategy>;
+
+}  // namespace blink