helix-mods/helix-view/src/document.rs
2021-06-18 17:42:38 +09:00

906 lines
29 KiB
Rust

use anyhow::{anyhow, Context, Error};
use std::cell::Cell;
use std::fmt::Display;
use std::future::Future;
use std::path::{Component, Path, PathBuf};
use std::str::FromStr;
use std::sync::Arc;
use helix_core::{
chars::{char_is_linebreak, char_is_whitespace},
history::History,
syntax::{LanguageConfiguration, LOADER},
ChangeSet, Diagnostic, Rope, Selection, State, Syntax, Transaction,
};
use crate::{DocumentId, ViewId};
use std::collections::HashMap;
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub enum Mode {
Normal,
Select,
Insert,
}
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub enum IndentStyle {
Tabs,
Spaces(u8),
}
pub struct Document {
// rope + selection
pub(crate) id: DocumentId,
text: Rope,
pub(crate) selections: HashMap<ViewId, Selection>,
path: Option<PathBuf>,
/// Current editing mode.
pub mode: Mode,
pub restore_cursor: bool,
/// Current indent style.
pub indent_style: IndentStyle,
syntax: Option<Syntax>,
// /// Corresponding language scope name. Usually `source.<lang>`.
pub(crate) language: Option<Arc<LanguageConfiguration>>,
/// Pending changes since last history commit.
changes: ChangeSet,
/// State at last commit. Used for calculating reverts.
old_state: Option<State>,
/// Undo tree.
// It can be used as a cell where we will take it out to get some parts of the history and put
// it back as it separated from the edits. We could split out the parts manually but that will
// be more troublesome.
history: Cell<History>,
last_saved_revision: usize,
version: i32, // should be usize?
diagnostics: Vec<Diagnostic>,
language_server: Option<Arc<helix_lsp::Client>>,
}
use std::fmt;
impl fmt::Debug for Document {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("Document")
.field("id", &self.id)
.field("text", &self.text)
.field("selections", &self.selections)
.field("path", &self.path)
.field("mode", &self.mode)
.field("restore_cursor", &self.restore_cursor)
.field("syntax", &self.syntax)
.field("language", &self.language)
.field("changes", &self.changes)
.field("old_state", &self.old_state)
// .field("history", &self.history)
.field("last_saved_revision", &self.last_saved_revision)
.field("version", &self.version)
.field("diagnostics", &self.diagnostics)
// .field("language_server", &self.language_server)
.finish()
}
}
impl Display for Mode {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
Mode::Normal => f.write_str("normal"),
Mode::Select => f.write_str("select"),
Mode::Insert => f.write_str("insert"),
}
}
}
impl FromStr for Mode {
type Err = Error;
fn from_str(s: &str) -> Result<Self, Self::Err> {
match s {
"normal" => Ok(Mode::Normal),
"select" => Ok(Mode::Select),
"insert" => Ok(Mode::Insert),
_ => Err(anyhow!("Invalid mode '{}'", s)),
}
}
}
/// Like std::mem::replace() except it allows the replacement value to be mapped from the
/// original value.
fn take_with<T, F>(mut_ref: &mut T, closure: F)
where
F: FnOnce(T) -> T,
{
use std::{panic, ptr};
unsafe {
let old_t = ptr::read(mut_ref);
let new_t = panic::catch_unwind(panic::AssertUnwindSafe(|| closure(old_t)))
.unwrap_or_else(|_| ::std::process::abort());
ptr::write(mut_ref, new_t);
}
}
/// Expands tilde `~` into users home directory if avilable, otherwise returns the path
/// unchanged. The tilde will only be expanded when present as the first component of the path
/// and only slash follows it.
pub fn expand_tilde(path: &Path) -> PathBuf {
let mut components = path.components().peekable();
if let Some(Component::Normal(c)) = components.peek() {
if c == &"~" {
if let Ok(home) = helix_core::home_dir() {
// it's ok to unwrap, the path starts with `~`
return home.join(path.strip_prefix("~").unwrap());
}
}
}
path.to_path_buf()
}
/// Replaces users home directory from `path` with tilde `~` if the directory
/// is available, otherwise returns the path unchanged.
pub fn fold_home_dir(path: &Path) -> PathBuf {
if let Ok(home) = helix_core::home_dir() {
if path.starts_with(&home) {
// it's ok to unwrap, the path starts with home dir
return PathBuf::from("~").join(path.strip_prefix(&home).unwrap());
}
}
path.to_path_buf()
}
/// Normalize a path, removing things like `.` and `..`.
///
/// CAUTION: This does not resolve symlinks (unlike
/// [`std::fs::canonicalize`]). This may cause incorrect or surprising
/// behavior at times. This should be used carefully. Unfortunately,
/// [`std::fs::canonicalize`] can be hard to use correctly, since it can often
/// fail, or on Windows returns annoying device paths. This is a problem Cargo
/// needs to improve on.
/// Copied from cargo: https://github.com/rust-lang/cargo/blob/070e459c2d8b79c5b2ac5218064e7603329c92ae/crates/cargo-util/src/paths.rs#L81
pub fn normalize_path(path: &Path) -> PathBuf {
let path = expand_tilde(path);
let mut components = path.components().peekable();
let mut ret = if let Some(c @ Component::Prefix(..)) = components.peek().cloned() {
components.next();
PathBuf::from(c.as_os_str())
} else {
PathBuf::new()
};
for component in components {
match component {
Component::Prefix(..) => unreachable!(),
Component::RootDir => {
ret.push(component.as_os_str());
}
Component::CurDir => {}
Component::ParentDir => {
ret.pop();
}
Component::Normal(c) => {
ret.push(c);
}
}
}
ret
}
/// Returns the canonical, absolute form of a path with all intermediate components normalized.
///
/// This function is used instead of `std::fs::canonicalize` because we don't want to verify
/// here if the path exists, just normalize it's components.
pub fn canonicalize_path(path: &Path) -> std::io::Result<PathBuf> {
let normalized = normalize_path(path);
if normalized.is_absolute() {
Ok(normalized)
} else {
std::env::current_dir().map(|current_dir| current_dir.join(normalized))
}
}
use helix_lsp::lsp;
use url::Url;
impl Document {
pub fn new(text: Rope) -> Self {
let changes = ChangeSet::new(&text);
let old_state = None;
Self {
id: DocumentId::default(),
path: None,
text,
selections: HashMap::default(),
indent_style: IndentStyle::Spaces(4),
mode: Mode::Normal,
restore_cursor: false,
syntax: None,
language: None,
changes,
old_state,
diagnostics: Vec::new(),
version: 0,
history: Cell::new(History::default()),
last_saved_revision: 0,
language_server: None,
}
}
// TODO: async fn?
pub fn load(path: PathBuf) -> Result<Self, Error> {
use std::{fs::File, io::BufReader};
let doc = if !path.exists() {
Rope::from("\n")
} else {
let file = File::open(&path).context(format!("unable to open {:?}", path))?;
let mut doc = Rope::from_reader(BufReader::new(file))?;
// add missing newline at the end of file
if doc.len_bytes() == 0 || doc.byte(doc.len_bytes() - 1) != b'\n' {
doc.insert_char(doc.len_chars(), '\n');
}
doc
};
let mut doc = Self::new(doc);
// set the path and try detecting the language
doc.set_path(&path)?;
doc.detect_indent_style();
Ok(doc)
}
// TODO: remove view_id dependency here
pub fn format(&mut self, view_id: ViewId) {
if let Some(language_server) = self.language_server() {
// TODO: await, no blocking
let transaction = helix_lsp::block_on(language_server.text_document_formatting(
self.identifier(),
lsp::FormattingOptions::default(),
None,
))
.map(|edits| {
helix_lsp::util::generate_transaction_from_edits(
self.text(),
edits,
language_server.offset_encoding(),
)
});
if let Ok(transaction) = transaction {
self.apply(&transaction, view_id);
self.append_changes_to_history(view_id);
}
}
}
// TODO: do we need some way of ensuring two save operations on the same doc can't run at once?
// or is that handled by the OS/async layer
pub fn save(&mut self) -> impl Future<Output = Result<(), anyhow::Error>> {
// we clone and move text + path into the future so that we asynchronously save the current
// state without blocking any further edits.
let text = self.text().clone();
let path = self.path.clone().expect("Can't save with no path set!"); // TODO: handle no path
let identifier = self.identifier();
// TODO: mark changes up to now as saved
let language_server = self.language_server.clone();
// reset the modified flag
let history = self.history.take();
self.last_saved_revision = history.current_revision();
self.history.set(history);
async move {
use tokio::{fs::File, io::AsyncWriteExt};
if let Some(parent) = path.parent() {
// TODO: display a prompt asking the user if the directories should be created
if !parent.exists() {
return Err(Error::msg(
"can't save file, parent directory does not exist",
));
}
}
let mut file = File::create(path).await?;
// write all the rope chunks to file
for chunk in text.chunks() {
file.write_all(chunk.as_bytes()).await?;
}
// TODO: flush?
if let Some(language_server) = language_server {
language_server
.text_document_did_save(identifier, &text)
.await?;
}
Ok(())
}
}
fn detect_language(&mut self) {
if let Some(path) = self.path() {
let loader = LOADER.get().unwrap();
let language_config = loader.language_config_for_file_name(path);
let scopes = loader.scopes();
self.set_language(language_config, scopes);
}
}
fn detect_indent_style(&mut self) {
// Build a histogram of the indentation *increases* between
// subsequent lines, ignoring lines that are all whitespace.
//
// Index 0 is for tabs, the rest are 1-8 spaces.
let histogram: [usize; 9] = {
let mut histogram = [0; 9];
let mut prev_line_is_tabs = false;
let mut prev_line_leading_count = 0usize;
// Loop through the lines, checking for and recording indentation
// increases as we go.
'outer: for line in self.text.lines().take(1000) {
let mut c_iter = line.chars();
// Is first character a tab or space?
let is_tabs = match c_iter.next() {
Some('\t') => true,
Some(' ') => false,
// Ignore blank lines.
Some(c) if char_is_linebreak(c) => continue,
_ => {
prev_line_is_tabs = false;
prev_line_leading_count = 0;
continue;
}
};
// Count the line's total leading tab/space characters.
let mut leading_count = 1;
let mut count_is_done = false;
for c in c_iter {
match c {
'\t' if is_tabs && !count_is_done => leading_count += 1,
' ' if !is_tabs && !count_is_done => leading_count += 1,
// We stop counting if we hit whitespace that doesn't
// qualify as indent or doesn't match the leading
// whitespace, but we don't exit the loop yet because
// we still want to determine if the line is blank.
c if char_is_whitespace(c) => count_is_done = true,
// Ignore blank lines.
c if char_is_linebreak(c) => continue 'outer,
_ => break,
}
// Bound the worst-case execution time for weird text files.
if leading_count > 256 {
continue 'outer;
}
}
// If there was an increase in indentation over the previous
// line, update the histogram with that increase.
if (prev_line_is_tabs == is_tabs || prev_line_leading_count == 0)
&& prev_line_leading_count < leading_count
{
if is_tabs {
histogram[0] += 1;
} else {
let amount = leading_count - prev_line_leading_count;
if amount <= 8 {
histogram[amount] += 1;
}
}
}
// Store this line's leading whitespace info for use with
// the next line.
prev_line_is_tabs = is_tabs;
prev_line_leading_count = leading_count;
}
// Give more weight to tabs, because their presence is a very
// strong indicator.
histogram[0] *= 2;
histogram
};
// Find the most frequent indent, its frequency, and the frequency of
// the next-most frequent indent.
let indent = histogram
.iter()
.enumerate()
.max_by_key(|kv| kv.1)
.unwrap()
.0;
let indent_freq = histogram[indent];
let indent_freq_2 = *histogram
.iter()
.enumerate()
.filter(|kv| kv.0 != indent)
.map(|kv| kv.1)
.max()
.unwrap();
// Use the auto-detected result if we're confident enough in its
// accuracy, based on some heuristics. Otherwise fall back to
// the language-based setting.
if indent_freq >= 1 && (indent_freq_2 as f64 / indent_freq as f64) < 0.66 {
// Use the auto-detected setting.
self.indent_style = match indent {
0 => IndentStyle::Tabs,
_ => IndentStyle::Spaces(indent as u8),
};
} else {
// Fall back to language-based setting.
let indent = self
.language
.as_ref()
.and_then(|config| config.indent.as_ref())
.map_or(" ", |config| config.unit.as_str()); // fallback to 2 spaces
self.indent_style = if indent.starts_with(' ') {
IndentStyle::Spaces(indent.len() as u8)
} else {
IndentStyle::Tabs
};
}
}
pub fn set_path(&mut self, path: &Path) -> Result<(), std::io::Error> {
let path = canonicalize_path(path)?;
// if parent doesn't exist we still want to open the document
// and error out when document is saved
self.path = Some(path);
// try detecting the language based on filepath
self.detect_language();
Ok(())
}
pub fn set_language(
&mut self,
language_config: Option<Arc<helix_core::syntax::LanguageConfiguration>>,
scopes: &[String],
) {
if let Some(language_config) = language_config {
if let Some(highlight_config) = language_config.highlight_config(scopes) {
let syntax = Syntax::new(&self.text, highlight_config);
self.syntax = Some(syntax);
// TODO: config.configure(scopes) is now delayed, is that ok?
}
self.language = Some(language_config);
} else {
self.syntax = None;
self.language = None;
};
}
pub fn set_language2(&mut self, scope: &str) {
let loader = LOADER.get().unwrap();
let language_config = loader.language_config_for_scope(scope);
let scopes = loader.scopes();
self.set_language(language_config, scopes);
}
pub fn set_language_server(&mut self, language_server: Option<Arc<helix_lsp::Client>>) {
self.language_server = language_server;
}
pub fn set_selection(&mut self, view_id: ViewId, selection: Selection) {
// TODO: use a transaction?
self.selections.insert(view_id, selection);
}
fn _apply(&mut self, transaction: &Transaction, view_id: ViewId) -> bool {
let old_doc = self.text().clone();
let success = transaction.changes().apply(&mut self.text);
if success {
// update the selection: either take the selection specified in the transaction, or map the
// current selection through changes.
let selection = transaction
.selection()
.cloned()
.unwrap_or_else(|| self.selection(view_id).clone().map(transaction.changes()));
self.set_selection(view_id, selection);
}
if !transaction.changes().is_empty() {
self.version += 1;
// update tree-sitter syntax tree
if let Some(syntax) = &mut self.syntax {
// TODO: no unwrap
syntax
.update(&old_doc, &self.text, transaction.changes())
.unwrap();
}
// map state.diagnostics over changes::map_pos too
// NOTE: seems to do nothing since the language server resends diagnostics on each edit
// for diagnostic in &mut self.diagnostics {
// use helix_core::Assoc;
// let changes = transaction.changes();
// diagnostic.range.start = changes.map_pos(diagnostic.range.start, Assoc::After);
// diagnostic.range.end = changes.map_pos(diagnostic.range.end, Assoc::After);
// diagnostic.line = self.text.char_to_line(diagnostic.range.start);
// }
// emit lsp notification
if let Some(language_server) = &self.language_server {
let notify = language_server.text_document_did_change(
self.versioned_identifier(),
&old_doc,
self.text(),
transaction.changes(),
);
if let Some(notify) = notify {
tokio::spawn(notify);
} //.expect("failed to emit textDocument/didChange");
}
}
success
}
pub fn apply(&mut self, transaction: &Transaction, view_id: ViewId) -> bool {
// store the state just before any changes are made. This allows us to undo to the
// state just before a transaction was applied.
if self.changes.is_empty() && !transaction.changes().is_empty() {
self.old_state = Some(State {
doc: self.text.clone(),
selection: self.selection(view_id).clone(),
});
}
let success = self._apply(transaction, view_id);
if !transaction.changes().is_empty() {
// Compose this transaction with the previous one
take_with(&mut self.changes, |changes| {
changes.compose(transaction.changes().clone())
});
}
success
}
pub fn undo(&mut self, view_id: ViewId) {
let mut history = self.history.take();
let success = if let Some(transaction) = history.undo() {
self._apply(&transaction, view_id)
} else {
false
};
self.history.set(history);
if success {
// reset changeset to fix len
self.changes = ChangeSet::new(self.text());
}
}
pub fn redo(&mut self, view_id: ViewId) {
let mut history = self.history.take();
let success = if let Some(transaction) = history.redo() {
self._apply(&transaction, view_id)
} else {
false
};
self.history.set(history);
if success {
// reset changeset to fix len
self.changes = ChangeSet::new(self.text());
}
}
pub fn earlier(&mut self, view_id: ViewId, uk: helix_core::history::UndoKind) {
let txns = self.history.get_mut().earlier(uk);
for txn in txns {
self._apply(&txn, view_id);
}
}
pub fn later(&mut self, view_id: ViewId, uk: helix_core::history::UndoKind) {
let txns = self.history.get_mut().later(uk);
for txn in txns {
self._apply(&txn, view_id);
}
}
pub fn append_changes_to_history(&mut self, view_id: ViewId) {
if self.changes.is_empty() {
return;
}
let new_changeset = ChangeSet::new(self.text());
let changes = std::mem::replace(&mut self.changes, new_changeset);
// Instead of doing this messy merge we could always commit, and based on transaction
// annotations either add a new layer or compose into the previous one.
let transaction =
Transaction::from(changes).with_selection(self.selection(view_id).clone());
// HAXX: we need to reconstruct the state as it was before the changes..
let old_state = self.old_state.take().expect("no old_state available");
let mut history = self.history.take();
history.commit_revision(&transaction, &old_state);
self.history.set(history);
}
#[inline]
pub fn id(&self) -> DocumentId {
self.id
}
#[inline]
pub fn is_modified(&self) -> bool {
let history = self.history.take();
let current_revision = history.current_revision();
self.history.set(history);
current_revision != self.last_saved_revision || !self.changes.is_empty()
}
#[inline]
pub fn mode(&self) -> Mode {
self.mode
}
#[inline]
/// Corresponding language scope name. Usually `source.<lang>`.
pub fn language(&self) -> Option<&str> {
self.language
.as_ref()
.map(|language| language.scope.as_str())
}
#[inline]
pub fn language_config(&self) -> Option<&LanguageConfiguration> {
self.language.as_deref()
}
#[inline]
/// Current document version, incremented at each change.
pub fn version(&self) -> i32 {
self.version
}
pub fn language_server(&self) -> Option<&helix_lsp::Client> {
self.language_server.as_deref()
}
/// Tree-sitter AST tree
pub fn syntax(&self) -> Option<&Syntax> {
self.syntax.as_ref()
}
/// Tab size in columns.
pub fn tab_width(&self) -> usize {
self.language
.as_ref()
.and_then(|config| config.indent.as_ref())
.map_or(4, |config| config.tab_width) // fallback to 4 columns
}
/// Returns a string containing a single level of indentation.
///
/// TODO: we might not need this function anymore, since the information
/// is conveniently available in `Document::indent_style` now.
pub fn indent_unit(&self) -> &'static str {
match self.indent_style {
IndentStyle::Tabs => "\t",
IndentStyle::Spaces(1) => " ",
IndentStyle::Spaces(2) => " ",
IndentStyle::Spaces(3) => " ",
IndentStyle::Spaces(4) => " ",
IndentStyle::Spaces(5) => " ",
IndentStyle::Spaces(6) => " ",
IndentStyle::Spaces(7) => " ",
IndentStyle::Spaces(8) => " ",
// Unsupported indentation style. This should never happen,
// but just in case fall back to two spaces.
_ => " ",
}
}
#[inline]
/// File path on disk.
pub fn path(&self) -> Option<&PathBuf> {
self.path.as_ref()
}
pub fn url(&self) -> Option<Url> {
self.path().map(|path| Url::from_file_path(path).unwrap())
}
pub fn text(&self) -> &Rope {
&self.text
}
pub fn selection(&self, view_id: ViewId) -> &Selection {
&self.selections[&view_id]
}
pub fn relative_path(&self) -> Option<PathBuf> {
let cwdir = std::env::current_dir().expect("couldn't determine current directory");
self.path.as_ref().map(|path| {
let path = fold_home_dir(path);
if path.is_relative() {
path
} else {
path.strip_prefix(cwdir)
.map(|p| p.to_path_buf())
.unwrap_or(path)
}
})
}
// pub fn slice<R>(&self, range: R) -> RopeSlice where R: RangeBounds {
// self.state.doc.slice
// }
// transact(Fn) ?
// -- LSP methods
pub fn identifier(&self) -> lsp::TextDocumentIdentifier {
lsp::TextDocumentIdentifier::new(self.url().unwrap())
}
pub fn versioned_identifier(&self) -> lsp::VersionedTextDocumentIdentifier {
lsp::VersionedTextDocumentIdentifier::new(self.url().unwrap(), self.version)
}
pub fn diagnostics(&self) -> &[Diagnostic] {
&self.diagnostics
}
pub fn set_diagnostics(&mut self, diagnostics: Vec<Diagnostic>) {
self.diagnostics = diagnostics;
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn changeset_to_changes() {
use helix_lsp::{lsp, Client, OffsetEncoding};
let text = Rope::from("hello");
let mut doc = Document::new(text);
let view = ViewId::default();
doc.set_selection(view, Selection::single(5, 5));
// insert
let transaction = Transaction::insert(doc.text(), doc.selection(view), " world".into());
let old_doc = doc.text().clone();
doc.apply(&transaction, view);
let changes = Client::changeset_to_changes(
&old_doc,
doc.text(),
transaction.changes(),
OffsetEncoding::Utf8,
);
assert_eq!(
changes,
&[lsp::TextDocumentContentChangeEvent {
range: Some(lsp::Range::new(
lsp::Position::new(0, 5),
lsp::Position::new(0, 5)
)),
text: " world".into(),
range_length: None,
}]
);
// delete
let transaction = transaction.invert(&old_doc);
let old_doc = doc.text().clone();
doc.apply(&transaction, view);
let changes = Client::changeset_to_changes(
&old_doc,
doc.text(),
transaction.changes(),
OffsetEncoding::Utf8,
);
// line: 0-based.
// col: 0-based, gaps between chars.
// 0 1 2 3 4 5 6 7 8 9 0 1
// |h|e|l|l|o| |w|o|r|l|d|
// -------------
// (0, 5)-(0, 11)
assert_eq!(
changes,
&[lsp::TextDocumentContentChangeEvent {
range: Some(lsp::Range::new(
lsp::Position::new(0, 5),
lsp::Position::new(0, 11)
)),
text: "".into(),
range_length: None,
}]
);
// replace
// also tests that changes are layered, positions depend on previous changes.
doc.set_selection(view, Selection::single(0, 5));
let transaction = Transaction::change(
doc.text(),
vec![(0, 2, Some("aei".into())), (3, 5, Some("ou".into()))].into_iter(),
);
// aeilou
let old_doc = doc.text().clone();
doc.apply(&transaction, view);
let changes = Client::changeset_to_changes(
&old_doc,
doc.text(),
transaction.changes(),
OffsetEncoding::Utf8,
);
assert_eq!(
changes,
&[
// 0 1 2 3 4 5
// |h|e|l|l|o|
// ----
//
// aeillo
lsp::TextDocumentContentChangeEvent {
range: Some(lsp::Range::new(
lsp::Position::new(0, 0),
lsp::Position::new(0, 2)
)),
text: "aei".into(),
range_length: None,
},
// 0 1 2 3 4 5 6
// |a|e|i|l|l|o|
// -----
//
// aeilou
lsp::TextDocumentContentChangeEvent {
range: Some(lsp::Range::new(
lsp::Position::new(0, 4),
lsp::Position::new(0, 6)
)),
text: "ou".into(),
range_length: None,
}
]
);
}
}