From 8826ad5ddd9dd86f48729334cf569b33a7c6e7c6 Mon Sep 17 00:00:00 2001 From: Antonio Scandurra Date: Mon, 6 Jun 2022 15:15:50 +0200 Subject: [PATCH] Make `Buffer::edit` and `MultiBuffer::edit` resilient to inverted ranges Previously, we would accept edits containing out-of-order ranges. When generating such ranges in our randomized tests, many invariants started breaking causing e.g. undo/redo to misbehave and operation application to panic. In theory, we should never pass inverted ranges, but this commit changes the above functions to swap the start and the end when that occurs to avoid breaking the entire system and panicking. --- crates/editor/src/display_map.rs | 2 +- crates/editor/src/multi_buffer.rs | 67 +++++++++++++++++++++---------- crates/language/src/buffer.rs | 11 ++++- 3 files changed, 55 insertions(+), 25 deletions(-) diff --git a/crates/editor/src/display_map.rs b/crates/editor/src/display_map.rs index 4378db5407..3e740f7b75 100644 --- a/crates/editor/src/display_map.rs +++ b/crates/editor/src/display_map.rs @@ -693,7 +693,7 @@ pub mod tests { } } _ => { - buffer.update(cx, |buffer, cx| buffer.randomly_edit(&mut rng, 5, cx)); + buffer.update(cx, |buffer, cx| buffer.randomly_mutate(&mut rng, 5, cx)); } } diff --git a/crates/editor/src/multi_buffer.rs b/crates/editor/src/multi_buffer.rs index 6dd1b0685b..32e2021fd2 100644 --- a/crates/editor/src/multi_buffer.rs +++ b/crates/editor/src/multi_buffer.rs @@ -17,6 +17,7 @@ use std::{ cell::{Ref, RefCell}, cmp, fmt, io, iter::{self, FromIterator}, + mem, ops::{Range, RangeBounds, Sub}, str, sync::Arc, @@ -298,7 +299,7 @@ impl MultiBuffer { pub fn edit_internal( &mut self, - edits_iter: I, + edits: I, autoindent: bool, cx: &mut ModelContext, ) where @@ -310,14 +311,16 @@ impl MultiBuffer { return; } + let snapshot = self.read(cx); + let edits = edits.into_iter().map(|(range, new_text)| { + let mut range = range.start.to_offset(&snapshot)..range.end.to_offset(&snapshot); + if range.start > range.end { + mem::swap(&mut range.start, &mut range.end); + } + (range, new_text) + }); + if let Some(buffer) = self.as_singleton() { - let snapshot = self.read(cx); - let edits = edits_iter.into_iter().map(|(range, new_text)| { - ( - range.start.to_offset(&snapshot)..range.end.to_offset(&snapshot), - new_text, - ) - }); return buffer.update(cx, |buffer, cx| { let language_name = buffer.language().map(|language| language.name()); let indent_size = cx.global::().tab_size(language_name.as_deref()); @@ -329,29 +332,26 @@ impl MultiBuffer { }); } - let snapshot = self.read(cx); let mut buffer_edits: HashMap, Arc, bool)>> = Default::default(); let mut cursor = snapshot.excerpts.cursor::(); - for (range, new_text) in edits_iter { + for (range, new_text) in edits { let new_text: Arc = new_text.into(); - let start = range.start.to_offset(&snapshot); - let end = range.end.to_offset(&snapshot); - cursor.seek(&start, Bias::Right, &()); - if cursor.item().is_none() && start == *cursor.start() { + cursor.seek(&range.start, Bias::Right, &()); + if cursor.item().is_none() && range.start == *cursor.start() { cursor.prev(&()); } let start_excerpt = cursor.item().expect("start offset out of bounds"); - let start_overshoot = start - cursor.start(); + let start_overshoot = range.start - cursor.start(); let buffer_start = start_excerpt.range.start.to_offset(&start_excerpt.buffer) + start_overshoot; - cursor.seek(&end, Bias::Right, &()); - if cursor.item().is_none() && end == *cursor.start() { + cursor.seek(&range.end, Bias::Right, &()); + if cursor.item().is_none() && range.end == *cursor.start() { cursor.prev(&()); } let end_excerpt = cursor.item().expect("end offset out of bounds"); - let end_overshoot = end - cursor.start(); + let end_overshoot = range.end - cursor.start(); let buffer_end = end_excerpt.range.start.to_offset(&end_excerpt.buffer) + end_overshoot; if start_excerpt.id == end_excerpt.id { @@ -373,7 +373,7 @@ impl MultiBuffer { .or_insert(Vec::new()) .push((end_excerpt_range, new_text.clone(), false)); - cursor.seek(&start, Bias::Right, &()); + cursor.seek(&range.start, Bias::Right, &()); cursor.next(&()); while let Some(excerpt) = cursor.item() { if excerpt.id == end_excerpt.id { @@ -1310,7 +1310,11 @@ impl MultiBuffer { let end = snapshot.clip_offset(rng.gen_range(new_start..=snapshot.len()), Bias::Right); let start = snapshot.clip_offset(rng.gen_range(new_start..=end), Bias::Right); last_end = Some(end); - let range = start..end; + + let mut range = start..end; + if rng.gen_bool(0.2) { + mem::swap(&mut range.start, &mut range.end); + } let new_text_len = rng.gen_range(0..10); let new_text: String = RandomCharIter::new(&mut *rng).take(new_text_len).collect(); @@ -1414,8 +1418,27 @@ impl MultiBuffer { mutation_count: usize, cx: &mut ModelContext, ) { + use rand::prelude::*; + if rng.gen_bool(0.7) || self.singleton { - self.randomly_edit(rng, mutation_count, cx); + let buffer = self + .buffers + .borrow() + .values() + .choose(rng) + .map(|state| state.buffer.clone()); + + if rng.gen() && buffer.is_some() { + buffer.unwrap().update(cx, |buffer, cx| { + if rng.gen() { + buffer.randomly_edit(rng, mutation_count, cx); + } else { + buffer.randomly_undo_redo(rng, cx); + } + }); + } else { + self.randomly_edit(rng, mutation_count, cx); + } } else { self.randomly_edit_excerpts(rng, mutation_count, cx); } @@ -3330,7 +3353,7 @@ mod tests { }); buffer_2.update(cx, |buffer, cx| { buffer.edit([(0..0, "Y")], cx); - buffer.edit([(6..0, "Z")], cx); + buffer.edit([(6..6, "Z")], cx); }); let new_snapshot = multibuffer.read(cx).snapshot(cx); diff --git a/crates/language/src/buffer.rs b/crates/language/src/buffer.rs index ccb3d382ea..38dbaa29fd 100644 --- a/crates/language/src/buffer.rs +++ b/crates/language/src/buffer.rs @@ -23,6 +23,7 @@ use std::{ ffi::OsString, future::Future, iter::{Iterator, Peekable}, + mem, ops::{Deref, DerefMut, Range}, path::{Path, PathBuf}, str, @@ -1108,7 +1109,10 @@ impl Buffer { // Skip invalid edits and coalesce contiguous ones. let mut edits: Vec<(Range, Arc)> = Vec::new(); for (range, new_text) in edits_iter { - let range = range.start.to_offset(self)..range.end.to_offset(self); + let mut range = range.start.to_offset(self)..range.end.to_offset(self); + if range.start > range.end { + mem::swap(&mut range.start, &mut range.end); + } let new_text = new_text.into(); if !new_text.is_empty() || !range.is_empty() { if let Some((prev_range, prev_text)) = edits.last_mut() { @@ -1452,7 +1456,10 @@ impl Buffer { } let new_start = last_end.map_or(0, |last_end| last_end + 1); - let range = self.random_byte_range(new_start, rng); + let mut range = self.random_byte_range(new_start, rng); + if rng.gen_bool(0.2) { + mem::swap(&mut range.start, &mut range.end); + } last_end = Some(range.end); let new_text_len = rng.gen_range(0..10);