From e468a1af350f344067f7c44aae060e2977798dbb Mon Sep 17 00:00:00 2001 From: Lukas Wirth Date: Sat, 5 Nov 2022 00:27:03 +0100 Subject: [PATCH] internal: Optimize `apply_document_changes` a bit --- crates/ide-db/src/line_index.rs | 7 +- crates/rust-analyzer/src/lsp_utils.rs | 111 ++++++++++++++------------ crates/rust-analyzer/src/main_loop.rs | 6 +- 3 files changed, 68 insertions(+), 56 deletions(-) diff --git a/crates/ide-db/src/line_index.rs b/crates/ide-db/src/line_index.rs index 75d49ff2fd..1b8f56187a 100644 --- a/crates/ide-db/src/line_index.rs +++ b/crates/ide-db/src/line_index.rs @@ -58,8 +58,11 @@ impl LineIndex { let mut utf16_lines = NoHashHashMap::default(); let mut utf16_chars = Vec::new(); - let mut newlines = vec![0.into()]; - let mut curr_row @ mut curr_col = 0.into(); + let mut newlines = Vec::with_capacity(16); + newlines.push(TextSize::from(0)); + + let mut curr_row = 0.into(); + let mut curr_col = 0.into(); let mut line = 0; for c in text.chars() { let c_len = TextSize::of(c); diff --git a/crates/rust-analyzer/src/lsp_utils.rs b/crates/rust-analyzer/src/lsp_utils.rs index c6a4db9a45..0971dc36f3 100644 --- a/crates/rust-analyzer/src/lsp_utils.rs +++ b/crates/rust-analyzer/src/lsp_utils.rs @@ -1,5 +1,5 @@ //! Utilities for LSP-related boilerplate code. -use std::{ops::Range, sync::Arc}; +use std::{mem, ops::Range, sync::Arc}; use lsp_server::Notification; @@ -133,11 +133,37 @@ impl GlobalState { } pub(crate) fn apply_document_changes( - old_text: &mut String, - content_changes: Vec, -) { + file_contents: impl FnOnce() -> String, + mut content_changes: Vec, +) -> String { + // Skip to the last full document change, as it invalidates all previous changes anyways. + let mut start = content_changes + .iter() + .rev() + .position(|change| change.range.is_none()) + .map(|idx| content_changes.len() - idx - 1) + .unwrap_or(0); + + let mut text: String = match content_changes.get_mut(start) { + // peek at the first content change as an optimization + Some(lsp_types::TextDocumentContentChangeEvent { range: None, text, .. }) => { + let text = mem::take(text); + start += 1; + + // The only change is a full document update + if start == content_changes.len() { + return text; + } + text + } + Some(_) => file_contents(), + // we received no content changes + None => return file_contents(), + }; + let mut line_index = LineIndex { - index: Arc::new(ide::LineIndex::new(old_text)), + // the index will be overwritten in the bottom loop's first iteration + index: Arc::new(ide::LineIndex::new(&text)), // We don't care about line endings or offset encoding here. endings: LineEndings::Unix, encoding: PositionEncoding::Utf16, @@ -148,38 +174,20 @@ pub(crate) fn apply_document_changes( // Some clients (e.g. Code) sort the ranges in reverse. As an optimization, we // remember the last valid line in the index and only rebuild it if needed. // The VFS will normalize the end of lines to `\n`. - enum IndexValid { - All, - UpToLineExclusive(u32), - } - - impl IndexValid { - fn covers(&self, line: u32) -> bool { - match *self { - IndexValid::UpToLineExclusive(to) => to > line, - _ => true, - } - } - } - - let mut index_valid = IndexValid::All; + let mut index_valid = !0u32; for change in content_changes { - match change.range { - Some(range) => { - if !index_valid.covers(range.end.line) { - line_index.index = Arc::new(ide::LineIndex::new(old_text)); - } - index_valid = IndexValid::UpToLineExclusive(range.start.line); - if let Ok(range) = from_proto::text_range(&line_index, range) { - old_text.replace_range(Range::::from(range), &change.text); - } + // The None case can't happen as we have handled it above already + if let Some(range) = change.range { + if index_valid <= range.end.line { + *Arc::make_mut(&mut line_index.index) = ide::LineIndex::new(&text); } - None => { - *old_text = change.text; - index_valid = IndexValid::UpToLineExclusive(0); + index_valid = range.start.line; + if let Ok(range) = from_proto::text_range(&line_index, range) { + text.replace_range(Range::::from(range), &change.text); } } } + text } /// Checks that the edits inside the completion and the additional edits do not overlap. @@ -242,11 +250,10 @@ mod tests { }; } - let mut text = String::new(); - apply_document_changes(&mut text, vec![]); + let text = apply_document_changes(|| String::new(), vec![]); assert_eq!(text, ""); - apply_document_changes( - &mut text, + let text = apply_document_changes( + || text, vec![TextDocumentContentChangeEvent { range: None, range_length: None, @@ -254,39 +261,39 @@ mod tests { }], ); assert_eq!(text, "the"); - apply_document_changes(&mut text, c![0, 3; 0, 3 => " quick"]); + let text = apply_document_changes(|| text, c![0, 3; 0, 3 => " quick"]); assert_eq!(text, "the quick"); - apply_document_changes(&mut text, c![0, 0; 0, 4 => "", 0, 5; 0, 5 => " foxes"]); + let text = apply_document_changes(|| text, c![0, 0; 0, 4 => "", 0, 5; 0, 5 => " foxes"]); assert_eq!(text, "quick foxes"); - apply_document_changes(&mut text, c![0, 11; 0, 11 => "\ndream"]); + let text = apply_document_changes(|| text, c![0, 11; 0, 11 => "\ndream"]); assert_eq!(text, "quick foxes\ndream"); - apply_document_changes(&mut text, c![1, 0; 1, 0 => "have "]); + let text = apply_document_changes(|| text, c![1, 0; 1, 0 => "have "]); assert_eq!(text, "quick foxes\nhave dream"); - apply_document_changes( - &mut text, + let text = apply_document_changes( + || text, c![0, 0; 0, 0 => "the ", 1, 4; 1, 4 => " quiet", 1, 16; 1, 16 => "s\n"], ); assert_eq!(text, "the quick foxes\nhave quiet dreams\n"); - apply_document_changes(&mut text, c![0, 15; 0, 15 => "\n", 2, 17; 2, 17 => "\n"]); + let text = apply_document_changes(|| text, c![0, 15; 0, 15 => "\n", 2, 17; 2, 17 => "\n"]); assert_eq!(text, "the quick foxes\n\nhave quiet dreams\n\n"); - apply_document_changes( - &mut text, + let text = apply_document_changes( + || text, c![1, 0; 1, 0 => "DREAM", 2, 0; 2, 0 => "they ", 3, 0; 3, 0 => "DON'T THEY?"], ); assert_eq!(text, "the quick foxes\nDREAM\nthey have quiet dreams\nDON'T THEY?\n"); - apply_document_changes(&mut text, c![0, 10; 1, 5 => "", 2, 0; 2, 12 => ""]); + let text = apply_document_changes(|| text, c![0, 10; 1, 5 => "", 2, 0; 2, 12 => ""]); assert_eq!(text, "the quick \nthey have quiet dreams\n"); - text = String::from("❤️"); - apply_document_changes(&mut text, c![0, 0; 0, 0 => "a"]); + let text = String::from("❤️"); + let text = apply_document_changes(|| text, c![0, 0; 0, 0 => "a"]); assert_eq!(text, "a❤️"); - text = String::from("a\nb"); - apply_document_changes(&mut text, c![0, 1; 1, 0 => "\nțc", 0, 1; 1, 1 => "d"]); + let text = String::from("a\nb"); + let text = apply_document_changes(|| text, c![0, 1; 1, 0 => "\nțc", 0, 1; 1, 1 => "d"]); assert_eq!(text, "adcb"); - text = String::from("a\nb"); - apply_document_changes(&mut text, c![0, 1; 1, 0 => "ț\nc", 0, 2; 0, 2 => "c"]); + let text = String::from("a\nb"); + let text = apply_document_changes(|| text, c![0, 1; 1, 0 => "ț\nc", 0, 2; 0, 2 => "c"]); assert_eq!(text, "ațc\ncb"); } diff --git a/crates/rust-analyzer/src/main_loop.rs b/crates/rust-analyzer/src/main_loop.rs index 7d10dc5d15..6e5da58fe3 100644 --- a/crates/rust-analyzer/src/main_loop.rs +++ b/crates/rust-analyzer/src/main_loop.rs @@ -759,8 +759,10 @@ impl GlobalState { let vfs = &mut this.vfs.write().0; let file_id = vfs.file_id(&path).unwrap(); - let mut text = String::from_utf8(vfs.file_contents(file_id).to_vec()).unwrap(); - apply_document_changes(&mut text, params.content_changes); + let text = apply_document_changes( + || std::str::from_utf8(vfs.file_contents(file_id)).unwrap().into(), + params.content_changes, + ); vfs.set_file_contents(path, Some(text.into_bytes())); }