gecko-dev/dom/base/StaticRange.h
Makoto Kato c2694625b5 Bug 1444847 - part 4: Implement mozilla::dom::StaticRange and static factory methods r=smaug
This patch is based on Makoto Kato-san's patch.

This patch implements `mozilla::dom::StaticRange` class and creating some
static factory methods.

Then, makes `AbstractRange` has a utility method of `SetStartAndEnd()`
method of `nsRange` and `StaticRange` for sharing same logic in one place.
However, there are some additional work is required only in `nsRange`, e.g.,
`nsRange` needs to start observing mutation of the range, but `StaticRange`
does not it.  Therefore, it's implemented as a template method which takes
`nsRange*` or `StaticRange*` as a parameter.  Then, each `DoSetRange()`
method of them can do different things without virtual calls.

Note that `StaticRange` does not have any properties, methods nor constructor.
Therefore, we need additional API to test it.

Differential Revision: https://phabricator.services.mozilla.com/D35143

--HG--
extra : moz-landing-system : lando
2019-06-28 07:48:52 +00:00

106 lines
4.4 KiB
C++

/* -*- 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/. */
#ifndef mozilla_dom_StaticRange_h
#define mozilla_dom_StaticRange_h
#include "mozilla/ErrorResult.h"
#include "mozilla/RangeBoundary.h"
#include "mozilla/dom/AbstractRange.h"
#include "nsWrapperCache.h"
namespace mozilla {
namespace dom {
class StaticRange final : public AbstractRange {
public:
explicit StaticRange(nsINode* aNode) : AbstractRange(aNode) {}
StaticRange() = delete;
explicit StaticRange(const StaticRange& aOther) = delete;
/**
* Create() may return `StaticRange` instance which is initialized with
* given range or points. If it fails initializing new range with the
* arguments, returns `nullptr`. `ErrorResult` is set to an error only
* when this returns `nullptr`. The error code indicates the reason why
* it couldn't initialize the instance.
*/
static already_AddRefed<StaticRange> Create(
const AbstractRange* aAbstractRange, ErrorResult& aRv) {
MOZ_ASSERT(aAbstractRange);
return StaticRange::Create(aAbstractRange->StartRef(),
aAbstractRange->EndRef(), aRv);
}
static already_AddRefed<StaticRange> Create(nsINode* aStartContainer,
uint32_t aStartOffset,
nsINode* aEndContainer,
uint32_t aEndOffset,
ErrorResult& aRv) {
return StaticRange::Create(RawRangeBoundary(aStartContainer, aStartOffset),
RawRangeBoundary(aEndContainer, aEndOffset),
aRv);
}
template <typename SPT, typename SRT, typename EPT, typename ERT>
static already_AddRefed<StaticRange> Create(
const RangeBoundaryBase<SPT, SRT>& aStartBoundary,
const RangeBoundaryBase<EPT, ERT>& aEndBoundary, ErrorResult& aRv);
protected:
virtual ~StaticRange() = default;
public:
NS_DECL_ISUPPORTS_INHERITED
// Need to override this for calling `DoSetRange()` from
// `NS_IMPL_MAIN_THREAD_ONLY_CYCLE_COLLECTING_RELEASE_WITH_LAST_RELEASE()`.
NS_IMETHODIMP_(void) DeleteCycleCollectable(void) override;
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_INHERITED(StaticRange,
AbstractRange)
JSObject* WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) final;
/**
* SetStartAndEnd() works similar to call both SetStart() and SetEnd().
* Different from calls them separately, this does nothing if either
* the start point or the end point is invalid point.
* If the specified start point is after the end point, the range will be
* collapsed at the end point. Similarly, if they are in different root,
* the range will be collapsed at the end point.
*/
nsresult SetStartAndEnd(nsINode* aStartContainer, uint32_t aStartOffset,
nsINode* aEndContainer, uint32_t aEndOffset) {
return SetStartAndEnd(RawRangeBoundary(aStartContainer, aStartOffset),
RawRangeBoundary(aEndContainer, aEndOffset));
}
template <typename SPT, typename SRT, typename EPT, typename ERT>
nsresult SetStartAndEnd(const RangeBoundaryBase<SPT, SRT>& aStartBoundary,
const RangeBoundaryBase<EPT, ERT>& aEndBoundary) {
return AbstractRange::SetStartAndEndInternal(aStartBoundary, aEndBoundary,
this);
}
protected:
/**
* DoSetRange() is called when `AbstractRange::SetStartAndEndInternal()` sets
* mStart and mEnd.
*
* @param aStartBoundary Computed start point. This must equals or be before
* aEndBoundary in the DOM tree order.
* @param aEndBoundary Computed end point.
* @param aRootNode The root node.
*/
template <typename SPT, typename SRT, typename EPT, typename ERT>
void DoSetRange(const RangeBoundaryBase<SPT, SRT>& aStartBoundary,
const RangeBoundaryBase<EPT, ERT>& aEndBoundary,
nsINode* aRootNode);
friend class AbstractRange;
};
} // namespace dom
} // namespace mozilla
#endif // #ifndef mozilla_dom_StaticRange_h