HackStudio+LibGUI: Implement matching curly brace highlighting

This works for C++ syntax highlighted text documents by caching the C++
token type in a new "arbitrary data" member of GTextDocumentSpan.

When the cursor is placed immediately before a '{' or immediately after
a '}', we highlight both of these brace buddies by changing their
corresponding spans to have a different background color.

..and spans can also now have a custom background color. :^)
This commit is contained in:
Andreas Kling 2019-11-18 19:10:06 +01:00
parent 5f7f97355e
commit c8e02e60a6
Notes: sideshowbarker 2024-07-19 11:09:13 +09:00
6 changed files with 89 additions and 1 deletions

View file

@ -1,4 +1,5 @@
#include "Editor.h"
#include "CppLexer.h"
#include "EditorWrapper.h"
#include <AK/FileSystemPath.h>
#include <LibCore/CDirIterator.h>
@ -170,3 +171,71 @@ void Editor::mousemove_event(GMouseEvent& event)
}
GApplication::the().hide_tooltip();
}
void Editor::cursor_did_change()
{
if (m_has_brace_buddies) {
if (m_brace_buddies[0].index >= 0 && m_brace_buddies[0].index < document().spans().size())
document().set_span_at_index(m_brace_buddies[0].index, m_brace_buddies[0].span_backup);
if (m_brace_buddies[1].index >= 0 && m_brace_buddies[1].index < document().spans().size())
document().set_span_at_index(m_brace_buddies[1].index, m_brace_buddies[1].span_backup);
m_has_brace_buddies = false;
update();
}
enum class Direction {
Forward,
Backward,
};
auto find_span_of_type = [&](int i, CppToken::Type type, CppToken::Type not_type, Direction direction) {
int nesting_level = 0;
bool forward = direction == Direction::Forward;
for (forward ? ++i : --i; forward ? (i < document().spans().size()) : (i >= 0); forward ? ++i : --i) {
auto& span = document().spans().at(i);
auto span_token_type = (CppToken::Type)((uintptr_t)span.data);
if (span_token_type == not_type) {
++nesting_level;
} else if (span_token_type == type) {
if (nesting_level-- <= 0)
return i;
}
}
return -1;
};
auto make_buddies = [&](int index0, int index1) {
auto& buddy0 = const_cast<GTextDocumentSpan&>(document().spans()[index0]);
auto& buddy1 = const_cast<GTextDocumentSpan&>(document().spans()[index1]);
m_has_brace_buddies = true;
m_brace_buddies[0].index = index0;
m_brace_buddies[1].index = index1;
m_brace_buddies[0].span_backup = buddy0;
m_brace_buddies[1].span_backup = buddy1;
buddy0.background_color = Color::DarkCyan;
buddy1.background_color = Color::DarkCyan;
buddy0.color = Color::White;
buddy1.color = Color::White;
update();
};
for (int i = 0; i < document().spans().size(); ++i) {
auto& span = const_cast<GTextDocumentSpan&>(document().spans().at(i));
auto token_type = (CppToken::Type)((uintptr_t)span.data);
if (token_type == CppToken::Type::LeftCurly && span.range.start() == cursor()) {
auto buddy = find_span_of_type(i, CppToken::Type::RightCurly, CppToken::Type::LeftCurly, Direction::Forward);
if (buddy != -1)
make_buddies(i, buddy);
return;
}
auto right_of_end = span.range.end();
right_of_end.set_column(right_of_end.column() + 1);
if (token_type == CppToken::Type::RightCurly && right_of_end == cursor()) {
auto buddy = find_span_of_type(i, CppToken::Type::LeftCurly, CppToken::Type::RightCurly, Direction::Backward);
if (buddy != -1)
make_buddies(i, buddy);
return;
}
}
}

View file

@ -20,6 +20,7 @@ private:
virtual void focusout_event(CEvent&) override;
virtual void paint_event(GPaintEvent&) override;
virtual void mousemove_event(GMouseEvent&) override;
virtual void cursor_did_change() override;
void show_documentation_tooltip_if_available(const String&, const Point& screen_location);
@ -28,4 +29,12 @@ private:
RefPtr<GWindow> m_documentation_tooltip_window;
RefPtr<HtmlView> m_documentation_html_view;
String m_last_parsed_token;
struct BuddySpan {
int index { -1 };
GTextDocumentSpan span_backup;
};
bool m_has_brace_buddies { false };
BuddySpan m_brace_buddies[2];
};

View file

@ -423,7 +423,7 @@ int main(int argc, char** argv)
remove_current_editor_action->set_enabled(g_all_editor_wrappers.size() > 1);
};
open_file("test.frm");
open_file("main.cpp");
update_actions();
return app.exec();
@ -484,6 +484,7 @@ static void rehighlight()
span.color = style.color;
span.font = style.font;
span.is_skippable = token.m_type == CppToken::Type::Whitespace;
span.data = (void*)token.m_type;
spans.append(span);
}
current_editor().document().set_spans(spans);

View file

@ -15,8 +15,10 @@ class GTextDocumentLine;
struct GTextDocumentSpan {
GTextRange range;
Color color;
Optional<Color> background_color;
bool is_skippable { false };
const Font* font { nullptr };
void* data { nullptr };
};
class GTextDocument : public RefCounted<GTextDocument> {
@ -54,6 +56,7 @@ public:
bool has_spans() const { return !m_spans.is_empty(); }
const Vector<GTextDocumentSpan>& spans() const { return m_spans; }
void set_span_at_index(int index, GTextDocumentSpan span) { m_spans[index] = move(span); }
void append_line(NonnullOwnPtr<GTextDocumentLine>);
void remove_line(int line_index);

View file

@ -389,6 +389,7 @@ void GTextEditor::paint_event(GPaintEvent& event)
for (int i = 0; i < visual_line_text.length(); ++i) {
const Font* font = &this->font();
Color color;
Optional<Color> background_color;
GTextPosition physical_position(line_index, start_of_visual_line + i);
// FIXME: This is *horribly* inefficient.
for (auto& span : document().spans()) {
@ -397,8 +398,11 @@ void GTextEditor::paint_event(GPaintEvent& event)
color = span.color;
if (span.font)
font = span.font;
background_color = span.background_color;
break;
}
if (background_color.has_value())
painter.fill_rect(character_rect, background_color.value());
painter.draw_text(character_rect, visual_line_text.substring_view(i, 1), *font, m_text_alignment, color);
character_rect.move_by(advance, 0);
}
@ -1135,6 +1139,7 @@ void GTextEditor::set_cursor(const GTextPosition& a_position)
update(old_cursor_line_rect);
update_cursor();
}
cursor_did_change();
if (on_cursor_change)
on_cursor_change();
}

View file

@ -120,6 +120,7 @@ protected:
virtual void leave_event(CEvent&) override;
virtual void context_menu_event(GContextMenuEvent&) override;
virtual void resize_event(GResizeEvent&) override;
virtual void cursor_did_change() {}
GTextPosition text_position_at(const Point&) const;