Files
kte/Buffer.cc
T
Claude f853fa60b1 Highlighting: invalidate from the edited row, not the whole buffer
Every edit bumped the buffer version (through SetDirty) and called
InvalidateFrom(0), so all cached spans and line states were discarded
and stateful highlighters re-lexed from row 0 to the viewport on each
keystroke.

Buffer mutators now report the row they changed (edited_at_), which
bumps the version and tells the engine to drop only rows from there
down; a row's highlighting depends only on rows above it. A version
change that arrives without that notice still clears everything, so a
missed path cannot show stale spans. The engine keeps states as a
contiguous vector and caches spans for every row it lexes. SetDirty no
longer touches the version: the edits themselves do, including undo
and redo back to the saved state (D9 still holds; its test now checks
the highlighting itself).

Typing near the end of a 100k-line C++ file: 46.3 ms -> 0.14 ms of
highlighting work per keystroke.

Audit finding P3.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015rcVQiiWyTzoNrsvLSaAfB
2026-09-24 09:16:04 -07:00

826 lines
23 KiB
C++

#include <fstream>
#include <sstream>
#include <filesystem>
#include <cstdlib>
#include <limits>
#include <cerrno>
#include <cstring>
#include <string_view>
#include <vector>
#include <fcntl.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "Buffer.h"
#include "SwapRecorder.h"
#include "UndoSystem.h"
#include "UndoTree.h"
#include "ErrorHandler.h"
#include "SyscallWrappers.h"
#include "ErrorRecovery.h"
// For reconstructing highlighter state on copies
#include "syntax/HighlighterRegistry.h"
#include "syntax/NullHighlighter.h"
Buffer::Buffer()
{
// Initialize undo system per buffer
undo_tree_ = std::make_unique<UndoTree>();
undo_sys_ = std::make_unique<UndoSystem>(*this, *undo_tree_);
}
bool
Buffer::stat_identity(const std::string &path, FileIdentity &out)
{
struct stat st{};
if (::stat(path.c_str(), &st) != 0) {
out.valid = false;
return false;
}
out.valid = true;
// Use nanosecond timestamp when available.
std::uint64_t ns = 0;
#if defined(__APPLE__)
ns = static_cast<std::uint64_t>(st.st_mtimespec.tv_sec) * 1000000000ull
+ static_cast<std::uint64_t>(st.st_mtimespec.tv_nsec);
#else
ns = static_cast<std::uint64_t>(st.st_mtim.tv_sec) * 1000000000ull
+ static_cast<std::uint64_t>(st.st_mtim.tv_nsec);
#endif
out.mtime_ns = ns;
out.size = static_cast<std::uint64_t>(st.st_size);
out.dev = static_cast<std::uint64_t>(st.st_dev);
out.ino = static_cast<std::uint64_t>(st.st_ino);
return true;
}
bool
Buffer::current_disk_identity(FileIdentity &out) const
{
if (!is_file_backed_ || filename_.empty()) {
out.valid = false;
return false;
}
return stat_identity(filename_, out);
}
bool
Buffer::ExternallyModifiedOnDisk() const
{
if (!is_file_backed_ || filename_.empty())
return false;
FileIdentity now{};
if (!current_disk_identity(now)) {
// If the file vanished, treat as modified when we previously had an identity.
return on_disk_identity_.valid;
}
if (!on_disk_identity_.valid)
return false;
return now.mtime_ns != on_disk_identity_.mtime_ns
|| now.size != on_disk_identity_.size
|| now.dev != on_disk_identity_.dev
|| now.ino != on_disk_identity_.ino;
}
void
Buffer::RefreshOnDiskIdentity()
{
FileIdentity id{};
if (current_disk_identity(id))
on_disk_identity_ = id;
}
static bool
write_all_fd(int fd, const char *data, std::size_t len, std::string &err)
{
std::size_t off = 0;
while (off < len) {
ssize_t n = ::write(fd, data + off, len - off);
if (n < 0) {
if (errno == EINTR)
continue;
err = std::string("Write failed: ") + std::strerror(errno);
return false;
}
off += static_cast<std::size_t>(n);
}
return true;
}
static void
best_effort_fsync_dir(const std::string &path)
{
try {
std::filesystem::path p(path);
std::filesystem::path dir = p.parent_path();
if (dir.empty())
return;
int dfd = kte::syscall::Open(dir.c_str(), O_RDONLY);
if (dfd < 0)
return;
(void) kte::syscall::Fsync(dfd);
(void) kte::syscall::Close(dfd);
} catch (...) {
// best-effort
}
}
static bool
atomic_write_file(const std::string &path, const char *data, std::size_t len, std::string &err)
{
// Create a temp file in the same directory so rename() is atomic.
std::filesystem::path p(path);
std::filesystem::path dir = p.parent_path();
std::string base = p.filename().string();
std::filesystem::path tmpl = dir / ("." + base + ".kte.tmp.XXXXXX");
std::string tmpl_s = tmpl.string();
// mkstemp requires a mutable buffer.
std::vector<char> buf(tmpl_s.begin(), tmpl_s.end());
buf.push_back('\0');
// Retry on transient errors for temp file creation
int fd = -1;
auto mkstemp_fn = [&]() -> bool {
// Reset buffer for each retry attempt
buf.assign(tmpl_s.begin(), tmpl_s.end());
buf.push_back('\0');
fd = kte::syscall::Mkstemp(buf.data());
return fd >= 0;
};
if (!kte::RetryOnTransientError(mkstemp_fn, kte::RetryPolicy::Aggressive(), err)) {
if (fd < 0) {
err = std::string("Failed to create temp file for save: ") + std::strerror(errno) + err;
}
return false;
}
std::string tmp_path(buf.data());
// If the destination exists, carry over its permissions.
struct stat dst_st{};
if (::stat(path.c_str(), &dst_st) == 0) {
(void) kte::syscall::Fchmod(fd, dst_st.st_mode);
}
bool ok = write_all_fd(fd, data, len, err);
if (ok) {
// Retry fsync on transient errors
auto fsync_fn = [&]() -> bool {
return kte::syscall::Fsync(fd) == 0;
};
std::string fsync_err;
if (!kte::RetryOnTransientError(fsync_fn, kte::RetryPolicy::Aggressive(), fsync_err)) {
err = std::string("fsync failed: ") + std::strerror(errno) + fsync_err;
ok = false;
}
}
(void) kte::syscall::Close(fd);
if (ok) {
if (::rename(tmp_path.c_str(), path.c_str()) != 0) {
err = std::string("rename failed: ") + std::strerror(errno);
ok = false;
}
}
if (!ok) {
(void) ::unlink(tmp_path.c_str());
return false;
}
best_effort_fsync_dir(path);
return true;
}
Buffer::Buffer(const std::string &path)
{
std::string err;
OpenFromFile(path, err);
}
// Copy constructor/assignment: perform a deep copy of core fields; reinitialize undo for the new buffer.
Buffer::Buffer(const Buffer &other)
{
curx_ = other.curx_;
cury_ = other.cury_;
rx_ = other.rx_;
nrows_ = other.nrows_;
rowoffs_ = other.rowoffs_;
coloffs_ = other.coloffs_;
rows_ = other.rows_;
content_ = other.content_;
rows_cache_dirty_ = other.rows_cache_dirty_;
filename_ = other.filename_;
is_file_backed_ = other.is_file_backed_;
dirty_ = other.dirty_;
read_only_ = other.read_only_;
mark_set_ = other.mark_set_;
mark_curx_ = other.mark_curx_;
mark_cury_ = other.mark_cury_;
// Copy edit mode + syntax/highlighting flags
edit_mode_ = other.edit_mode_;
edit_mode_detected_ = other.edit_mode_detected_;
version_ = other.version_;
syntax_enabled_ = other.syntax_enabled_;
syntax_user_override_ = other.syntax_user_override_;
filetype_ = other.filetype_;
// Fresh undo system for the copy
undo_tree_ = std::make_unique<UndoTree>();
undo_sys_ = std::make_unique<UndoSystem>(*this, *undo_tree_);
// Recreate a highlighter engine for this copy based on filetype/syntax state
if (syntax_enabled_) {
// Allocate engine and install an appropriate highlighter
highlighter_ = std::make_unique<kte::HighlighterEngine>();
if (!filetype_.empty()) {
auto hl = kte::HighlighterRegistry::CreateFor(filetype_);
if (hl) {
highlighter_->SetHighlighter(std::move(hl));
} else {
// Unsupported filetype -> NullHighlighter keeps syntax pipeline active
highlighter_->SetHighlighter(std::make_unique<kte::NullHighlighter>());
}
} else {
// No filetype -> keep syntax enabled but use NullHighlighter
highlighter_->SetHighlighter(std::make_unique<kte::NullHighlighter>());
}
// Fresh engine has empty caches; nothing to invalidate
}
}
Buffer &
Buffer::operator=(const Buffer &other)
{
if (this == &other)
return *this;
curx_ = other.curx_;
cury_ = other.cury_;
rx_ = other.rx_;
nrows_ = other.nrows_;
rowoffs_ = other.rowoffs_;
coloffs_ = other.coloffs_;
rows_ = other.rows_;
content_ = other.content_;
rows_cache_dirty_ = other.rows_cache_dirty_;
filename_ = other.filename_;
is_file_backed_ = other.is_file_backed_;
dirty_ = other.dirty_;
read_only_ = other.read_only_;
mark_set_ = other.mark_set_;
mark_curx_ = other.mark_curx_;
mark_cury_ = other.mark_cury_;
edit_mode_ = other.edit_mode_;
edit_mode_detected_ = other.edit_mode_detected_;
version_ = other.version_;
syntax_enabled_ = other.syntax_enabled_;
syntax_user_override_ = other.syntax_user_override_;
filetype_ = other.filetype_;
// Recreate undo system for this instance
undo_tree_ = std::make_unique<UndoTree>();
undo_sys_ = std::make_unique<UndoSystem>(*this, *undo_tree_);
// Recreate highlighter engine consistent with syntax settings
highlighter_.reset();
if (syntax_enabled_) {
highlighter_ = std::make_unique<kte::HighlighterEngine>();
if (!filetype_.empty()) {
auto hl = kte::HighlighterRegistry::CreateFor(filetype_);
if (hl) {
highlighter_->SetHighlighter(std::move(hl));
} else {
highlighter_->SetHighlighter(std::make_unique<kte::NullHighlighter>());
}
} else {
highlighter_->SetHighlighter(std::make_unique<kte::NullHighlighter>());
}
}
return *this;
}
// Move constructor: move all fields and update UndoSystem's buffer reference
Buffer::Buffer(Buffer &&other) noexcept
: curx_(other.curx_),
cury_(other.cury_),
rx_(other.rx_),
nrows_(other.nrows_),
rowoffs_(other.rowoffs_),
coloffs_(other.coloffs_),
rows_(std::move(other.rows_)),
filename_(std::move(other.filename_)),
is_file_backed_(other.is_file_backed_),
dirty_(other.dirty_),
read_only_(other.read_only_),
mark_set_(other.mark_set_),
mark_curx_(other.mark_curx_),
mark_cury_(other.mark_cury_),
visual_line_active_(other.visual_line_active_),
visual_line_anchor_y_(other.visual_line_anchor_y_),
visual_line_active_y_(other.visual_line_active_y_),
undo_tree_(std::move(other.undo_tree_)),
undo_sys_(std::move(other.undo_sys_))
{
// Move edit mode + syntax/highlighting state
edit_mode_ = other.edit_mode_;
edit_mode_detected_ = other.edit_mode_detected_;
version_ = other.version_;
syntax_enabled_ = other.syntax_enabled_;
syntax_user_override_ = other.syntax_user_override_;
filetype_ = std::move(other.filetype_);
highlighter_ = std::move(other.highlighter_);
content_ = std::move(other.content_);
rows_cache_dirty_ = other.rows_cache_dirty_;
on_disk_identity_ = other.on_disk_identity_;
// Non-owning: the recorder object itself is owned by SwapManager and outlives
// this move. The caller (Editor) is responsible for calling SwapManager::Rehome()
// so the journal's Buffer* key follows this object to its new address.
swap_rec_ = other.swap_rec_;
other.swap_rec_ = nullptr;
// Update UndoSystem's buffer reference to point to this object
if (undo_sys_) {
undo_sys_->UpdateBufferReference(*this);
}
}
// Move assignment: move all fields and update UndoSystem's buffer reference
Buffer &
Buffer::operator=(Buffer &&other) noexcept
{
if (this == &other)
return *this;
curx_ = other.curx_;
cury_ = other.cury_;
rx_ = other.rx_;
nrows_ = other.nrows_;
rowoffs_ = other.rowoffs_;
coloffs_ = other.coloffs_;
rows_ = std::move(other.rows_);
filename_ = std::move(other.filename_);
is_file_backed_ = other.is_file_backed_;
dirty_ = other.dirty_;
read_only_ = other.read_only_;
mark_set_ = other.mark_set_;
mark_curx_ = other.mark_curx_;
mark_cury_ = other.mark_cury_;
visual_line_active_ = other.visual_line_active_;
visual_line_anchor_y_ = other.visual_line_anchor_y_;
visual_line_active_y_ = other.visual_line_active_y_;
undo_tree_ = std::move(other.undo_tree_);
undo_sys_ = std::move(other.undo_sys_);
// Move edit mode + syntax/highlighting state
edit_mode_ = other.edit_mode_;
edit_mode_detected_ = other.edit_mode_detected_;
version_ = other.version_;
syntax_enabled_ = other.syntax_enabled_;
syntax_user_override_ = other.syntax_user_override_;
filetype_ = std::move(other.filetype_);
highlighter_ = std::move(other.highlighter_);
content_ = std::move(other.content_);
rows_cache_dirty_ = other.rows_cache_dirty_;
on_disk_identity_ = other.on_disk_identity_;
// Non-owning: the recorder object itself is owned by SwapManager and outlives
// this move. The caller (Editor) is responsible for calling SwapManager::Rehome()
// so the journal's Buffer* key follows this object to its new address.
swap_rec_ = other.swap_rec_;
other.swap_rec_ = nullptr;
// Update UndoSystem's buffer reference to point to this object
if (undo_sys_) {
undo_sys_->UpdateBufferReference(*this);
}
return *this;
}
bool
Buffer::OpenFromFile(const std::string &path, std::string &err)
{
auto normalize_path = [](const std::string &in) -> std::string {
std::string expanded = in;
// Expand leading '~' to HOME
if (!expanded.empty() && expanded[0] == '~') {
const char *home = std::getenv("HOME");
if (home && expanded.size() >= 2 && (expanded[1] == '/' || expanded[1] == '\\')) {
expanded = std::string(home) + expanded.substr(1);
} else if (home && expanded.size() == 1) {
expanded = std::string(home);
}
}
try {
std::filesystem::path p(expanded);
if (std::filesystem::exists(p)) {
return std::filesystem::canonical(p).string();
}
return std::filesystem::absolute(p).string();
} catch (...) {
// On any error, fall back to input
return expanded;
}
};
const std::string norm = normalize_path(path);
// If the file doesn't exist, initialize an empty, non-file-backed buffer
// with the provided filename. Do not touch the filesystem until Save/SaveAs.
if (!std::filesystem::exists(norm)) {
rows_.clear();
nrows_ = 0;
filename_ = norm;
is_file_backed_ = false;
dirty_ = false;
// Reset cursor/viewport state
curx_ = cury_ = rx_ = 0;
rowoffs_ = coloffs_ = 0;
mark_set_ = false;
mark_curx_ = mark_cury_ = 0;
// Empty PieceTable
content_.Clear();
rows_cache_dirty_ = true;
// History recorded against the previous content no longer applies.
if (undo_sys_)
undo_sys_->clear();
MarkContentChanged();
return true;
}
std::ifstream in(norm, std::ios::in | std::ios::binary);
if (!in) {
err = "Failed to open file: " + norm;
kte::ErrorHandler::Instance().Error("Buffer", err, norm);
return false;
}
// Read entire file into PieceTable as-is
std::string data;
in.seekg(0, std::ios::end);
if (!in) {
err = "Failed to seek to end of file: " + norm;
kte::ErrorHandler::Instance().Error("Buffer", err, norm);
return false;
}
auto sz = in.tellg();
if (sz < 0) {
err = "Failed to get file size: " + norm;
kte::ErrorHandler::Instance().Error("Buffer", err, norm);
return false;
}
if (sz > 0) {
data.resize(static_cast<std::size_t>(sz));
in.seekg(0, std::ios::beg);
if (!in) {
err = "Failed to seek to beginning of file: " + norm;
kte::ErrorHandler::Instance().Error("Buffer", err, norm);
return false;
}
in.read(data.data(), static_cast<std::streamsize>(data.size()));
if (!in && !in.eof()) {
err = "Failed to read file: " + norm;
kte::ErrorHandler::Instance().Error("Buffer", err, norm);
return false;
}
// Validate we read the expected number of bytes
const std::streamsize bytes_read = in.gcount();
if (bytes_read != static_cast<std::streamsize>(data.size())) {
err = "Partial read of file (expected " + std::to_string(data.size()) +
" bytes, got " + std::to_string(bytes_read) + "): " + norm;
kte::ErrorHandler::Instance().Error("Buffer", err, norm);
return false;
}
}
content_.Clear();
if (!data.empty())
content_.Append(data.data(), data.size());
rows_cache_dirty_ = true;
nrows_ = 0; // not used under PieceTable
filename_ = norm;
is_file_backed_ = true;
dirty_ = false;
RefreshOnDiskIdentity();
// Reset/initialize undo system for this loaded file
if (!undo_tree_)
undo_tree_ = std::make_unique<UndoTree>();
if (!undo_sys_)
undo_sys_ = std::make_unique<UndoSystem>(*this, *undo_tree_);
// Clear any existing history for a fresh load
undo_sys_->clear();
MarkContentChanged();
// Reset cursor/viewport state
curx_ = cury_ = rx_ = 0;
rowoffs_ = coloffs_ = 0;
mark_set_ = false;
mark_curx_ = mark_cury_ = 0;
return true;
}
bool
Buffer::Save(std::string &err) const
{
if (!is_file_backed_ || filename_.empty()) {
err = "Buffer is not file-backed; use SaveAs()";
return false;
}
const std::size_t sz = content_.Size();
const char *data = sz ? content_.Data() : nullptr;
if (sz && !data) {
err = "Internal error: buffer materialization failed";
return false;
}
if (!atomic_write_file(filename_, data ? data : "", sz, err)) {
kte::ErrorHandler::Instance().Error("Buffer", err, filename_);
return false;
}
// Update observed on-disk identity after a successful save.
const_cast<Buffer *>(this)->RefreshOnDiskIdentity();
// Note: const method cannot change dirty_. Intentionally const to allow UI code
// to decide when to flip dirty flag after successful save.
return true;
}
bool
Buffer::SaveAs(const std::string &path, std::string &err)
{
// Normalize output path first
std::string out_path;
try {
std::filesystem::path p(path);
// Do a light expansion of '~'
std::string expanded = path;
if (!expanded.empty() && expanded[0] == '~') {
const char *home = std::getenv("HOME");
if (home && expanded.size() >= 2 && (expanded[1] == '/' || expanded[1] == '\\'))
expanded = std::string(home) + expanded.substr(1);
else if (home && expanded.size() == 1)
expanded = std::string(home);
}
std::filesystem::path ep(expanded);
out_path = std::filesystem::absolute(ep).string();
} catch (...) {
out_path = path;
}
const std::size_t sz = content_.Size();
const char *data = sz ? content_.Data() : nullptr;
if (sz && !data) {
err = "Internal error: buffer materialization failed";
return false;
}
if (!atomic_write_file(out_path, data ? data : "", sz, err)) {
kte::ErrorHandler::Instance().Error("Buffer", err, out_path);
return false;
}
filename_ = out_path;
is_file_backed_ = true;
dirty_ = false;
RefreshOnDiskIdentity();
return true;
}
std::string
Buffer::AsString() const
{
std::stringstream ss;
ss << "Buffer<" << this->filename_;
if (this->Dirty()) {
ss << "*";
}
ss << ">: " << content_.LineCount() << " lines";
return ss.str();
}
// --- Raw editing APIs (no undo recording, cursor untouched) ---
void
Buffer::insert_text(int row, int col, std::string_view text)
{
if (row < 0)
row = 0;
if (col < 0)
col = 0;
const std::size_t off = content_.LineColToByteOffset(static_cast<std::size_t>(row),
static_cast<std::size_t>(col));
if (!text.empty()) {
content_.Insert(off, text.data(), text.size());
rows_cache_dirty_ = true;
edited_at_(row);
if (swap_rec_)
swap_rec_->OnInsert(row, col, text);
}
}
// ===== Adapter helpers for PieceTable-backed Buffer =====
std::string_view
Buffer::GetLineView(std::size_t row) const
{
// Get byte range for the logical line and return a view into materialized data
auto range = content_.GetLineRange(row); // [start,end) in bytes
const char *base = content_.Data(); // materializes if needed
if (!base)
return std::string_view();
const std::size_t start = range.first;
const std::size_t len = (range.second > range.first) ? (range.second - range.first) : 0;
return std::string_view(base + start, len);
}
void
Buffer::ensure_rows_cache() const
{
std::lock_guard<std::mutex> lock(buffer_mutex_);
if (!rows_cache_dirty_)
return;
rows_.clear();
const std::size_t lc = content_.LineCount();
rows_.reserve(lc);
for (std::size_t i = 0; i < lc; ++i) {
rows_.emplace_back(content_.GetLine(i));
}
// Keep nrows_ in sync for any legacy code that still reads it
const_cast<Buffer *>(this)->nrows_ = rows_.size();
rows_cache_dirty_ = false;
}
std::size_t
Buffer::content_LineCount_() const
{
return content_.LineCount();
}
#if defined(KTE_TESTS)
std::string
Buffer::BytesForTests() const
{
const std::size_t sz = content_.Size();
if (sz == 0)
return std::string();
const char *data = content_.Data();
if (!data)
return std::string();
return std::string(data, data + sz);
}
#endif
void
Buffer::delete_text(int row, int col, std::size_t len)
{
if (len == 0)
return;
if (row < 0)
row = 0;
if (col < 0)
col = 0;
// `len` counts each newline as one character, so the deletion is simply
// the next `len` bytes from the (clamped) start, capped at end of buffer.
const std::size_t start = content_.LineColToByteOffset(static_cast<std::size_t>(row),
static_cast<std::size_t>(col));
const std::size_t total = content_.Size();
const std::size_t actual = (total > start) ? std::min(len, total - start) : 0;
if (actual == 0)
return;
content_.Delete(start, actual);
rows_cache_dirty_ = true;
edited_at_(row);
if (swap_rec_)
swap_rec_->OnDelete(row, col, actual);
}
void
Buffer::split_line(int row, const int col)
{
int c = col;
if (row < 0)
row = 0;
if (c < 0)
c = 0;
const std::size_t off = content_.LineColToByteOffset(static_cast<std::size_t>(row),
static_cast<std::size_t>(c));
const char nl = '\n';
content_.Insert(off, &nl, 1);
rows_cache_dirty_ = true;
edited_at_(row);
if (swap_rec_)
swap_rec_->OnInsert(row, c, std::string_view("\n", 1));
}
void
Buffer::join_lines(int row)
{
if (row < 0)
row = 0;
std::size_t r = static_cast<std::size_t>(row);
if (r + 1 >= content_.LineCount())
return;
const int col = static_cast<int>(content_.GetLine(r).size());
// Delete the newline between line r and r+1
std::size_t end_of_line = content_.LineColToByteOffset(r, std::numeric_limits<std::size_t>::max());
// end_of_line now equals line end (clamped before newline). The newline should be exactly at this position.
content_.Delete(end_of_line, 1);
rows_cache_dirty_ = true;
edited_at_(row);
if (swap_rec_)
swap_rec_->OnDelete(row, col, 1);
}
void
Buffer::insert_row(int row, const std::string_view text)
{
if (row < 0)
row = 0;
std::size_t off = content_.LineColToByteOffset(static_cast<std::size_t>(row), 0);
if (!text.empty())
content_.Insert(off, text.data(), text.size());
const char nl = '\n';
content_.Insert(off + text.size(), &nl, 1);
rows_cache_dirty_ = true;
edited_at_(row);
if (swap_rec_) {
// Avoid allocation: emit the row text insertion (if any) and the newline insertion.
if (!text.empty())
swap_rec_->OnInsert(row, 0, text);
swap_rec_->OnInsert(row, static_cast<int>(text.size()), std::string_view("\n", 1));
}
}
void
Buffer::delete_row(int row)
{
if (row < 0)
row = 0;
std::size_t r = static_cast<std::size_t>(row);
if (r >= content_.LineCount())
return;
auto range = content_.GetLineRange(r); // [start,end)
// If not last line, ensure we include the separating newline by using end as-is (which points to next line start)
// If last line, end may equal total_size_. We still delete [start,end) which removes the last line content.
const std::size_t start = range.first;
const std::size_t end = range.second;
const std::size_t actual = (end > start) ? (end - start) : 0;
if (actual == 0)
return;
content_.Delete(start, actual);
rows_cache_dirty_ = true;
edited_at_(row);
if (swap_rec_)
swap_rec_->OnDelete(row, 0, actual);
}
void
Buffer::replace_all_bytes(const std::string_view bytes)
{
content_.Clear();
if (!bytes.empty())
content_.Append(bytes.data(), bytes.size());
rows_cache_dirty_ = true;
MarkContentChanged();
}
// Undo system accessors
UndoSystem *
Buffer::Undo()
{
return undo_sys_.get();
}
const UndoSystem *
Buffer::Undo() const
{
return undo_sys_.get();
}