ladybird/Userland/Libraries/LibWeb/Page/EditEventHandler.cpp
Luke 5beacf08a2 LibWeb: Make the node mutation algorithms more spec compliant
The mutation algorithms now more closely follow the spec and
fixes some assertion failures in tests such as Acid3 and Dromaeo.

The main thing that is missing right now is passing exceptions to the
bindings layer. This is because of issue #6075. I spent a while trying
to work it out and got so frustrated I just left it as a FIXME. Besides
that, the algorithms bail at the appropriate points.

This also makes the adopting steps in the document more spec compliant
as it's needed by the insertion algorithm. While I was at it, I added
the adoptNode IDL binding.

This adds a bunch of ancestor/descendant checks to TreeNode as well.
I moved the "remove_all_children" function to Node as it needs to use
the full remove algorithm instead of simply removing it from
the child list.
2021-04-06 21:42:00 +02:00

121 lines
4.8 KiB
C++

/*
* Copyright (c) 2020, the SerenityOS developers.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 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 A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#include "EditEventHandler.h"
#include <AK/StringBuilder.h>
#include <LibWeb/DOM/Document.h>
#include <LibWeb/DOM/Position.h>
#include <LibWeb/DOM/Range.h>
#include <LibWeb/DOM/Text.h>
#include <LibWeb/Layout/InitialContainingBlockBox.h>
#include <LibWeb/Layout/LayoutPosition.h>
#include <LibWeb/Page/Frame.h>
namespace Web {
// This method is quite convoluted but this is necessary to make editing feel intuitive.
void EditEventHandler::handle_delete(DOM::Range& range)
{
auto* start = downcast<DOM::Text>(range.start_container());
auto* end = downcast<DOM::Text>(range.end_container());
if (start == end) {
StringBuilder builder;
builder.append(start->data().substring_view(0, range.start_offset()));
builder.append(end->data().substring_view(range.end_offset()));
start->set_data(builder.to_string());
} else {
// Remove all the nodes that are fully enclosed in the range.
HashTable<DOM::Node*> queued_for_deletion;
for (auto* node = start->next_in_pre_order(); node; node = node->next_in_pre_order()) {
if (node == end)
break;
queued_for_deletion.set(node);
}
for (auto* parent = start->parent(); parent; parent = parent->parent())
queued_for_deletion.remove(parent);
for (auto* parent = end->parent(); parent; parent = parent->parent())
queued_for_deletion.remove(parent);
for (auto* node : queued_for_deletion)
node->remove();
// Join the parent nodes of start and end.
DOM::Node *insert_after = start, *remove_from = end, *parent_of_end = end->parent();
while (remove_from) {
auto* next_sibling = remove_from->next_sibling();
remove_from->remove();
insert_after->parent()->insert_before(*remove_from, *insert_after);
insert_after = remove_from;
remove_from = next_sibling;
}
if (!parent_of_end->has_children()) {
if (parent_of_end->parent())
parent_of_end->remove();
}
// Join the start and end nodes.
StringBuilder builder;
builder.append(start->data().substring_view(0, range.start_offset()));
builder.append(end->data().substring_view(range.end_offset()));
start->set_data(builder.to_string());
end->remove();
}
// FIXME: When nodes are removed from the DOM, the associated layout nodes become stale and still
// remain in the layout tree. This has to be fixed, this just causes everything to be recomputed
// which really hurts performance.
m_frame.document()->force_layout();
m_frame.did_edit({});
}
void EditEventHandler::handle_insert(DOM::Position position, u32 code_point)
{
if (is<DOM::Text>(*position.node())) {
auto& node = downcast<DOM::Text>(*position.node());
StringBuilder builder;
builder.append(node.data().substring_view(0, position.offset()));
builder.append_code_point(code_point);
builder.append(node.data().substring_view(position.offset()));
node.set_data(builder.to_string());
node.invalidate_style();
}
// FIXME: When nodes are removed from the DOM, the associated layout nodes become stale and still
// remain in the layout tree. This has to be fixed, this just causes everything to be recomputed
// which really hurts performance.
m_frame.document()->force_layout();
m_frame.did_edit({});
}
}