gecko-dev/editor/libeditor/PlaceholderTransaction.cpp
Masayuki Nakano 2c93600238 Bug 1797247 - part 1: Add delete transaction classes to use build time type checks r=m_kato
First, `EditorBase::CreateTransactionForDeleteSelection` returns an instance of
`EditAggregateTransaction`. It's a base class of `PlaceholderTransaction` and
`DeleteRangeTransaction` but it's also a concrete class.  However, it's too
generic.  Therefore, this patch creates `DeleteMultipleRangesTransaction` which
is a simple sub-class of it, and makes `EditAggregateTransaction` be an abstract
class.  Then, add `AddChild` methods to each concrete class to restrict the
type of child transactions.

Next, `DeleteRangeTransaction` contains only `DeleteNodeTransaction` and
`DeleteTextTransaction`.  Therefore, once they have a common base class,
we can check the type easier.  Therefore, this patch also adds
`DeleteContentTransactionBase` and
`EditorBase::CreateTransactionForCollapsedRange` becomes clearer what it
returns.

With these changes, `DeleteRangeTransaction` obviously contains only
`DeleteContentTransactionBase`, `DeleteMultipleRangesTransaction` contains only
`DeleteRangeTransaction`, `DeleteNodeTransaction` and `DeleteTextTransaction`.
And they are guaranteed at build time (at least from outside the classes).
***
fix

Differential Revision: https://phabricator.services.mozilla.com/D169038
2023-02-15 22:17:17 +00:00

352 lines
14 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
#include "PlaceholderTransaction.h"
#include <utility>
#include "CompositionTransaction.h"
#include "mozilla/EditorBase.h"
#include "mozilla/Logging.h"
#include "mozilla/ToString.h"
#include "mozilla/dom/Selection.h"
#include "nsGkAtoms.h"
#include "nsQueryObject.h"
namespace mozilla {
using namespace dom;
PlaceholderTransaction::PlaceholderTransaction(
EditorBase& aEditorBase, nsStaticAtom& aName,
Maybe<SelectionState>&& aSelState)
: mEditorBase(&aEditorBase),
mCompositionTransaction(nullptr),
mStartSel(*std::move(aSelState)),
mAbsorb(true),
mCommitted(false) {
mName = &aName;
}
NS_IMPL_CYCLE_COLLECTION_CLASS(PlaceholderTransaction)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(PlaceholderTransaction,
EditAggregateTransaction)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mEditorBase);
NS_IMPL_CYCLE_COLLECTION_UNLINK(mStartSel);
NS_IMPL_CYCLE_COLLECTION_UNLINK(mEndSel);
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(PlaceholderTransaction,
EditAggregateTransaction)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mEditorBase);
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mStartSel);
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mEndSel);
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PlaceholderTransaction)
NS_INTERFACE_MAP_END_INHERITING(EditAggregateTransaction)
NS_IMPL_ADDREF_INHERITED(PlaceholderTransaction, EditAggregateTransaction)
NS_IMPL_RELEASE_INHERITED(PlaceholderTransaction, EditAggregateTransaction)
void PlaceholderTransaction::AppendChild(EditTransactionBase& aTransaction) {
mChildren.AppendElement(aTransaction);
}
NS_IMETHODIMP PlaceholderTransaction::DoTransaction() {
MOZ_LOG(
GetLogModule(), LogLevel::Info,
("%p PlaceholderTransaction::%s this={ mName=%s }", this, __FUNCTION__,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
NS_IMETHODIMP PlaceholderTransaction::UndoTransaction() {
MOZ_LOG(GetLogModule(), LogLevel::Info,
("%p PlaceholderTransaction::%s this={ mName=%s } "
"Start==============================",
this, __FUNCTION__,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
if (NS_WARN_IF(!mEditorBase)) {
return NS_ERROR_NOT_INITIALIZED;
}
// Undo transactions.
nsresult rv = EditAggregateTransaction::UndoTransaction();
if (NS_FAILED(rv)) {
NS_WARNING("EditAggregateTransaction::UndoTransaction() failed");
return rv;
}
// now restore selection
RefPtr<Selection> selection = mEditorBase->GetSelection();
if (NS_WARN_IF(!selection)) {
return NS_ERROR_FAILURE;
}
rv = mStartSel.RestoreSelection(*selection);
NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
"SelectionState::RestoreSelection() failed");
MOZ_LOG(GetLogModule(), LogLevel::Info,
("%p PlaceholderTransaction::%s this={ mName=%s } "
"End==============================",
this, __FUNCTION__,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return rv;
}
NS_IMETHODIMP PlaceholderTransaction::RedoTransaction() {
MOZ_LOG(GetLogModule(), LogLevel::Info,
("%p PlaceholderTransaction::%s this={ mName=%s } "
"Start==============================",
this, __FUNCTION__,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
if (NS_WARN_IF(!mEditorBase)) {
return NS_ERROR_NOT_INITIALIZED;
}
// Redo transactions.
nsresult rv = EditAggregateTransaction::RedoTransaction();
if (NS_FAILED(rv)) {
NS_WARNING("EditAggregateTransaction::RedoTransaction() failed");
return rv;
}
// now restore selection
RefPtr<Selection> selection = mEditorBase->GetSelection();
if (NS_WARN_IF(!selection)) {
return NS_ERROR_FAILURE;
}
rv = mEndSel.RestoreSelection(*selection);
NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
"SelectionState::RestoreSelection() failed");
MOZ_LOG(GetLogModule(), LogLevel::Info,
("%p PlaceholderTransaction::%s this={ mName=%s } "
"End==============================",
this, __FUNCTION__,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return rv;
}
NS_IMETHODIMP PlaceholderTransaction::Merge(nsITransaction* aOtherTransaction,
bool* aDidMerge) {
if (NS_WARN_IF(!aDidMerge) || NS_WARN_IF(!aOtherTransaction)) {
return NS_ERROR_INVALID_ARG;
}
// set out param default value
*aDidMerge = false;
if (mForwardingTransaction) {
MOZ_ASSERT_UNREACHABLE(
"tried to merge into a placeholder that was in "
"forwarding mode!");
return NS_ERROR_FAILURE;
}
RefPtr<EditTransactionBase> otherTransactionBase =
aOtherTransaction->GetAsEditTransactionBase();
if (!otherTransactionBase) {
MOZ_LOG(GetLogModule(), LogLevel::Debug,
("%p PlaceholderTransaction::%s(aOtherTransaction=%p) this={ "
"mName=%s } returned false due to non edit transaction",
this, __FUNCTION__, aOtherTransaction,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
// We are absorbing all transactions if mAbsorb is lit.
if (mAbsorb) {
if (CompositionTransaction* otherCompositionTransaction =
otherTransactionBase->GetAsCompositionTransaction()) {
// special handling for CompositionTransaction's: they need to merge with
// any previous CompositionTransaction in this placeholder, if possible.
if (!mCompositionTransaction) {
// this is the first IME txn in the placeholder
mCompositionTransaction = otherCompositionTransaction;
AppendChild(*otherCompositionTransaction);
} else {
bool didMerge;
mCompositionTransaction->Merge(otherCompositionTransaction, &didMerge);
if (!didMerge) {
// it wouldn't merge. Earlier IME txn is already committed and will
// not absorb further IME txns. So just stack this one after it
// and remember it as a candidate for further merges.
mCompositionTransaction = otherCompositionTransaction;
AppendChild(*otherCompositionTransaction);
}
}
} else {
PlaceholderTransaction* otherPlaceholderTransaction =
otherTransactionBase->GetAsPlaceholderTransaction();
if (!otherPlaceholderTransaction) {
// See bug 171243: just drop incoming placeholders on the floor.
// Their children will be swallowed by this preexisting one.
AppendChild(*otherTransactionBase);
}
}
*aDidMerge = true;
// RememberEndingSelection();
// efficiency hack: no need to remember selection here, as we haven't yet
// finished the initial batch and we know we will be told when the batch
// ends. we can remeber the selection then.
return NS_OK;
}
// merge typing or IME or deletion transactions if the selection matches
if (mCommitted ||
(mName != nsGkAtoms::TypingTxnName && mName != nsGkAtoms::IMETxnName &&
mName != nsGkAtoms::DeleteTxnName)) {
MOZ_LOG(GetLogModule(), LogLevel::Debug,
("%p PlaceholderTransaction::%s(aOtherTransaction=%p) this={ "
"mName=%s } returned false due to non mergable transaction",
this, __FUNCTION__, aOtherTransaction,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
PlaceholderTransaction* otherPlaceholderTransaction =
otherTransactionBase->GetAsPlaceholderTransaction();
if (!otherPlaceholderTransaction) {
MOZ_LOG(GetLogModule(), LogLevel::Debug,
("%p PlaceholderTransaction::%s(aOtherTransaction=%p) this={ "
"mName=%s } returned false due to non placeholder transaction",
this, __FUNCTION__, aOtherTransaction,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
RefPtr<nsAtom> otherTransactionName = otherPlaceholderTransaction->GetName();
if (!otherTransactionName || otherTransactionName == nsGkAtoms::_empty ||
otherTransactionName != mName) {
MOZ_LOG(GetLogModule(), LogLevel::Debug,
("%p PlaceholderTransaction::%s(aOtherTransaction=%p) this={ "
"mName=%s } returned false due to non mergable placeholder "
"transaction",
this, __FUNCTION__, aOtherTransaction,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
// check if start selection of next placeholder matches
// end selection of this placeholder
// XXX Theese checks seem wrong. The ending selection is initialized with
// actual Selection rather than expected Selection. Therefore, even when
// web apps modifies Selection, we don't merge mergable transactions.
// If the new transaction's starting Selection is not a caret, we shouldn't be
// merged with it because it's probably caused deleting the selection.
if (!otherPlaceholderTransaction->mStartSel.HasOnlyCollapsedRange()) {
MOZ_LOG(GetLogModule(), LogLevel::Debug,
("%p PlaceholderTransaction::%s(aOtherTransaction=%p) this={ "
"mName=%s } returned false due to not collapsed selection at "
"start of new transactions",
this, __FUNCTION__, aOtherTransaction,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
// If our ending Selection is not a caret, we should not be merged with it
// because we probably changed format of a block or style of text.
if (!mEndSel.HasOnlyCollapsedRange()) {
MOZ_LOG(GetLogModule(), LogLevel::Debug,
("%p PlaceholderTransaction::%s(aOtherTransaction=%p) this={ "
"mName=%s } returned false due to not collapsed selection at end "
"of previous transactions",
this, __FUNCTION__, aOtherTransaction,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
// If the caret positions are now in different root nodes, e.g., the previous
// caret position was removed from the DOM tree, this merge should not be
// done.
const bool isPreviousCaretPointInSameRootOfNewCaretPoint = [&]() {
nsINode* previousRootInCurrentDOMTree = mEndSel.GetCommonRootNode();
return previousRootInCurrentDOMTree &&
previousRootInCurrentDOMTree ==
otherPlaceholderTransaction->mStartSel.GetCommonRootNode();
}();
if (!isPreviousCaretPointInSameRootOfNewCaretPoint) {
MOZ_LOG(GetLogModule(), LogLevel::Debug,
("%p PlaceholderTransaction::%s(aOtherTransaction=%p) this={ "
"mName=%s } returned false due to the caret points are in "
"different root nodes",
this, __FUNCTION__, aOtherTransaction,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
// If the caret points of end of us and start of new transaction are not same,
// we shouldn't merge them.
if (!otherPlaceholderTransaction->mStartSel.Equals(mEndSel)) {
MOZ_LOG(GetLogModule(), LogLevel::Debug,
("%p PlaceholderTransaction::%s(aOtherTransaction=%p) this={ "
"mName=%s } returned false due to caret positions were different",
this, __FUNCTION__, aOtherTransaction,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
mAbsorb = true; // we need to start absorbing again
otherPlaceholderTransaction->ForwardEndBatchTo(*this);
// AppendChild(editTransactionBase);
// see bug 171243: we don't need to merge placeholders
// into placeholders. We just reactivate merging in the
// pre-existing placeholder and drop the new one on the floor. The
// EndPlaceHolderBatch() call on the new placeholder will be
// forwarded to this older one.
DebugOnly<nsresult> rvIgnored = RememberEndingSelection();
NS_WARNING_ASSERTION(
NS_SUCCEEDED(rvIgnored),
"PlaceholderTransaction::RememberEndingSelection() failed, but "
"ignored");
*aDidMerge = true;
MOZ_LOG(GetLogModule(), LogLevel::Debug,
("%p PlaceholderTransaction::%s(aOtherTransaction=%p) this={ "
"mName=%s } returned true",
this, __FUNCTION__, aOtherTransaction,
nsAtomCString(mName ? mName.get() : nsGkAtoms::_empty).get()));
return NS_OK;
}
nsresult PlaceholderTransaction::EndPlaceHolderBatch() {
mAbsorb = false;
if (mForwardingTransaction) {
if (mForwardingTransaction) {
DebugOnly<nsresult> rvIgnored =
mForwardingTransaction->EndPlaceHolderBatch();
NS_WARNING_ASSERTION(
NS_SUCCEEDED(rvIgnored),
"PlaceholderTransaction::EndPlaceHolderBatch() failed, but ignored");
}
}
// remember our selection state.
nsresult rv = RememberEndingSelection();
NS_WARNING_ASSERTION(
NS_SUCCEEDED(rv),
"PlaceholderTransaction::RememberEndingSelection() failed");
return rv;
}
nsresult PlaceholderTransaction::RememberEndingSelection() {
if (NS_WARN_IF(!mEditorBase)) {
return NS_ERROR_NOT_INITIALIZED;
}
RefPtr<Selection> selection = mEditorBase->GetSelection();
if (NS_WARN_IF(!selection)) {
return NS_ERROR_FAILURE;
}
mEndSel.SaveSelection(*selection);
return NS_OK;
}
} // namespace mozilla