Code Review: That's just like your struct, man.

This commit is contained in:
Martin Haug 2022-02-23 20:06:48 +01:00
parent 4c8634c600
commit 9fda623b02
8 changed files with 173 additions and 161 deletions

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@ -55,7 +55,7 @@ fn bench_scan(iai: &mut Iai) {
}
fn bench_tokenize(iai: &mut Iai) {
iai.run(|| Tokens::new(black_box(SRC), black_box(TokenMode::Markup), 0).count());
iai.run(|| Tokens::new(black_box(SRC), black_box(TokenMode::Markup)).count());
}
fn bench_parse(iai: &mut Iai) {

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@ -4,19 +4,10 @@ use std::sync::Arc;
use crate::syntax::{Green, GreenNode, NodeKind};
use super::{
is_newline, parse, parse_block, parse_markup_elements, parse_template, TokenMode,
is_newline, parse, reparse_block, reparse_markup_elements, reparse_template,
TokenMode,
};
type ReparseFunc = fn(
&str,
&str,
usize,
isize,
&[Green],
bool,
usize,
) -> Option<(Vec<Green>, bool, usize)>;
/// Allows partial refreshs of the [`Green`] node tree.
///
/// This struct holds a description of a change. Its methods can be used to try
@ -55,16 +46,12 @@ impl Reparser<'_> {
let child_mode = green.kind().mode().unwrap_or(TokenMode::Code);
let original_count = green.children().len();
// Save the current indent if this is a markup node.
let indent = match green.kind() {
NodeKind::Markup(n) => *n,
_ => 0,
};
let mut search = SearchState::default();
let mut ahead_nontrivia = None;
// Whether the first node that should be replaced is at start.
let mut at_start = true;
// Whether the last searched child is the outermost child.
let mut child_outermost = false;
// Find the the first child in the range of children to reparse.
@ -83,18 +70,17 @@ impl Reparser<'_> {
search = if child_span.end == self.replace_range.end
&& child_mode == TokenMode::Markup
{
SearchState::RequireNonWS(pos)
SearchState::RequireNonTrivia(pos)
} else {
SearchState::Contained(pos)
};
} else if child_span.contains(&self.replace_range.start) {
search = SearchState::Inside(pos);
} else {
if (self.replace_range.len() != 0
|| self.replace_range.end != child_span.end
|| ahead_nontrivia.is_none())
&& (!child.kind().is_space()
&& child.kind() != &NodeKind::Semicolon)
if (!child.kind().is_space()
&& child.kind() != &NodeKind::Semicolon)
&& (ahead_nontrivia.is_none()
|| self.replace_range.start > child_span.end)
{
ahead_nontrivia = Some((pos, at_start));
}
@ -103,12 +89,12 @@ impl Reparser<'_> {
}
SearchState::Inside(start) => {
if child_span.end == self.replace_range.end {
search = SearchState::RequireNonWS(start);
search = SearchState::RequireNonTrivia(start);
} else if child_span.end > self.replace_range.end {
search = SearchState::SpanFound(start, pos);
}
}
SearchState::RequireNonWS(start) => {
SearchState::RequireNonTrivia(start) => {
if !child.kind().is_trivia() {
search = SearchState::SpanFound(start, pos);
}
@ -118,11 +104,21 @@ impl Reparser<'_> {
offset += child.len();
child_outermost = outermost && i + 1 == original_count;
if search.end().is_some() {
if search.done().is_some() {
break;
}
}
// If we were looking for a non-whitespace element and hit the end of
// the file here, we instead use EOF as the end of the span.
if let SearchState::RequireNonTrivia(start) = search {
search = SearchState::SpanFound(start, GreenPos {
idx: green.children().len() - 1,
offset: offset - green.children().last().unwrap().len(),
})
}
if let SearchState::Contained(pos) = search {
let child = &mut green.children_mut()[pos.idx];
let prev_len = child.len();
@ -139,20 +135,20 @@ impl Reparser<'_> {
}
let superseded_span = pos.offset .. pos.offset + prev_len;
let func: Option<ReparseFunc> = match child.kind() {
NodeKind::Template => Some(parse_template),
NodeKind::Block => Some(parse_block),
let func: Option<ReparseMode> = match child.kind() {
NodeKind::Template => Some(ReparseMode::Template),
NodeKind::Block => Some(ReparseMode::Block),
_ => None,
};
// Return if the element was reparsable on its own, otherwise try to
// treat it as a markup element.
if let Some(func) = func {
if let Some(result) = self.replace(
green,
func,
pos.idx .. pos.idx + 1,
superseded_span,
at_start,
indent,
outermost,
) {
return Some(result);
@ -160,11 +156,13 @@ impl Reparser<'_> {
}
}
if !matches!(green.kind(), NodeKind::Markup(_)) {
return None;
}
// Save the current indent if this is a markup node and stop otherwise.
let indent = match green.kind() {
NodeKind::Markup(n) => *n,
_ => return None,
};
let (mut start, end) = search.end()?;
let (mut start, end) = search.done()?;
if let Some((ahead, ahead_at_start)) = ahead_nontrivia {
let ahead_kind = green.children()[ahead.idx].kind();
@ -179,13 +177,12 @@ impl Reparser<'_> {
let superseded_span =
start.offset .. end.offset + green.children()[end.idx].len();
self.replace(
green,
parse_markup_elements,
ReparseMode::MarkupElements(at_start, indent),
start.idx .. end.idx + 1,
superseded_span,
at_start,
indent,
outermost,
)
}
@ -193,19 +190,17 @@ impl Reparser<'_> {
fn replace(
&self,
green: &mut GreenNode,
func: ReparseFunc,
mode: ReparseMode,
superseded_idx: Range<usize>,
superseded_span: Range<usize>,
at_start: bool,
indent: usize,
outermost: bool,
) -> Option<Range<usize>> {
let superseded_start = superseded_idx.start;
let differential: isize =
self.replace_len as isize - self.replace_range.len() as isize;
let newborn_span = superseded_span.start
..
(superseded_span.end as isize + differential) as usize;
let superseded_start = superseded_idx.start;
let newborn_end = (superseded_span.end as isize + differential) as usize;
let newborn_span = superseded_span.start .. newborn_end;
let mut prefix = "";
for (i, c) in self.src[.. newborn_span.start].char_indices().rev() {
@ -215,15 +210,27 @@ impl Reparser<'_> {
prefix = &self.src[i .. newborn_span.start];
}
let (newborns, terminated, amount) = func(
&prefix,
&self.src[newborn_span.start ..],
newborn_span.len(),
differential,
&green.children()[superseded_start ..],
at_start,
indent,
)?;
let (newborns, terminated, amount) = match mode {
ReparseMode::Block => reparse_block(
&prefix,
&self.src[newborn_span.start ..],
newborn_span.len(),
),
ReparseMode::Template => reparse_template(
&prefix,
&self.src[newborn_span.start ..],
newborn_span.len(),
),
ReparseMode::MarkupElements(at_start, indent) => reparse_markup_elements(
&prefix,
&self.src[newborn_span.start ..],
newborn_span.len(),
differential,
&green.children()[superseded_start ..],
at_start,
indent,
),
}?;
// Do not accept unclosed nodes if the old node wasn't at the right edge
// of the tree.
@ -236,6 +243,8 @@ impl Reparser<'_> {
}
}
/// The position of a green node in terms of its string offset and index within
/// the parent node.
#[derive(Clone, Copy, Debug, PartialEq)]
struct GreenPos {
idx: usize,
@ -256,7 +265,7 @@ enum SearchState {
Inside(GreenPos),
/// The search has found the end of the modified nodes but the change
/// touched its boundries so another non-trivia node is needed.
RequireNonWS(GreenPos),
RequireNonTrivia(GreenPos),
/// The search has concluded by finding a start and an end index for nodes
/// with a pending reparse.
SpanFound(GreenPos, GreenPos),
@ -269,17 +278,29 @@ impl Default for SearchState {
}
impl SearchState {
fn end(&self) -> Option<(GreenPos, GreenPos)> {
fn done(self) -> Option<(GreenPos, GreenPos)> {
match self {
Self::NoneFound => None,
Self::Contained(s) => Some((*s, *s)),
Self::Contained(s) => Some((s, s)),
Self::Inside(_) => None,
Self::RequireNonWS(_) => None,
Self::SpanFound(s, e) => Some((*s, *e)),
Self::RequireNonTrivia(_) => None,
Self::SpanFound(s, e) => Some((s, e)),
}
}
}
/// Which reparse function to choose for a span of elements.
#[derive(Clone, Copy, Debug, PartialEq)]
enum ReparseMode {
/// Reparse a code block with its braces.
Block,
/// Reparse a template, including its square brackets.
Template,
/// Reparse elements of the markup. The variant carries whether the node is
/// `at_start` and the minimum indent of the containing markup node.
MarkupElements(bool, usize),
}
impl NodeKind {
/// Whether this node has to appear at the start of a line.
pub fn only_at_start(&self) -> bool {
@ -330,7 +351,7 @@ mod tests {
test("#grid(columns: (auto, 1fr, 40%), [*plonk*], rect(width: 100%, height: 1pt, fill: conifer), [thing])", 34 .. 41, "_bar_", 33 .. 40);
test("{let i=1; for x in range(5) {i}}", 6 .. 6, " ", 0 .. 33);
test("{let i=1; for x in range(5) {i}}", 13 .. 14, " ", 0 .. 33);
test("hello~~{x}", 7 .. 10, "#f()", 0 .. 11);
test("hello~~{x}", 7 .. 10, "#f()", 5 .. 11);
test("this~is -- in my opinion -- spectacular", 8 .. 10, "---", 5 .. 25);
test("understanding `code` is complicated", 15 .. 15, "C ", 14 .. 22);
test("{ let x = g() }", 10 .. 12, "f(54", 0 .. 17);
@ -344,8 +365,8 @@ mod tests {
#[test]
fn test_parse_incremental_whitespace_invariants() {
test("hello \\ world", 7 .. 8, "a ", 6 .. 14);
test("hello \\ world", 7 .. 8, " a", 6 .. 14);
test("hello \\ world", 7 .. 8, "a ", 0 .. 14);
test("hello \\ world", 7 .. 8, " a", 0 .. 14);
test("x = y", 1 .. 1, " + y", 0 .. 6);
test("x = y", 1 .. 1, " + y\n", 0 .. 7);
test("abc\n= a heading\njoke", 3 .. 4, "\nmore\n\n", 0 .. 21);
@ -353,13 +374,13 @@ mod tests {
test("#let x = (1, 2 + ;~ Five\r\n\r", 20 .. 23, "2.", 18 .. 23);
test("hey #myfriend", 4 .. 4, "\\", 0 .. 14);
test("hey #myfriend", 4 .. 4, "\\", 3 .. 6);
test("= foo\nbar\n - a\n - b", 6 .. 9, "", 0..11);
test("= foo\n bar\n baz", 6..8, "", 0..15);
test("= foo\nbar\n - a\n - b", 6 .. 9, "", 0 .. 11);
test("= foo\n bar\n baz", 6 .. 8, "", 0 .. 15);
}
#[test]
fn test_parse_incremental_type_invariants() {
test("a #for x in array {x}", 18 .. 21, "[#x]", 0 .. 22);
test("a #for x in array {x}", 18 .. 21, "[#x]", 2 .. 22);
test("a #let x = 1 {5}", 3 .. 6, "if", 2 .. 11);
test("a {let x = 1 {5}} b", 3 .. 6, "if", 2 .. 16);
test("#let x = 1 {5}", 4 .. 4, " if", 0 .. 13);

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@ -30,7 +30,7 @@ pub fn parse(src: &str) -> Arc<GreenNode> {
/// Parse some markup without the topmost node. Returns `Some` if all of the
/// input was consumed.
pub fn parse_markup_elements(
pub fn reparse_markup_elements(
prefix: &str,
src: &str,
end_pos: usize,
@ -43,11 +43,11 @@ pub fn parse_markup_elements(
let mut node: Option<&Green> = None;
let mut iter = reference.iter();
let mut offset = 0;
let mut offset = differential;
let mut replaced = 0;
let mut stopped = false;
while !p.eof() {
'outer: while !p.eof() {
if let Some(NodeKind::Space(1 ..)) = p.peek() {
if p.column(p.current_end()) < column {
return None;
@ -56,44 +56,36 @@ pub fn parse_markup_elements(
markup_node(&mut p, &mut at_start);
if p.prev_end() >= end_pos {
let recent = p.children.last().unwrap();
let recent_start = p.prev_end() - recent.len();
if p.prev_end() < end_pos {
continue;
}
while offset <= recent_start {
if let Some(node) = node {
// The nodes are equal, at the same position and have the
// same content. The parsing trees have converged again, so
// the reparse may stop here.
if (offset as isize + differential) as usize == recent_start
&& node == recent
{
replaced -= 1;
stopped = true;
break;
}
}
let recent = p.children.last().unwrap();
let recent_start = p.prev_end() - recent.len();
let result = iter.next();
if let Some(node) = node {
offset += node.len();
}
node = result;
if node.is_none() {
break;
} else {
replaced += 1;
while offset <= recent_start as isize {
if let Some(node) = node {
// The nodes are equal, at the same position and have the
// same content. The parsing trees have converged again, so
// the reparse may stop here.
if offset == recent_start as isize && node == recent {
replaced -= 1;
stopped = true;
break 'outer;
}
}
if stopped {
if let Some(node) = node {
offset += node.len() as isize;
}
node = iter.next();
if node.is_none() {
break;
}
}
}
if p.prev_end() < end_pos {
return None;
replaced += 1;
}
}
if p.eof() && !stopped {
@ -109,14 +101,10 @@ pub fn parse_markup_elements(
}
/// Parse a template literal. Returns `Some` if all of the input was consumed.
pub fn parse_template(
pub fn reparse_template(
prefix: &str,
src: &str,
end_pos: usize,
_: isize,
_: &[Green],
_: bool,
_: usize,
) -> Option<(Vec<Green>, bool, usize)> {
let mut p = Parser::with_prefix(prefix, src, TokenMode::Code);
if !p.at(&NodeKind::LeftBracket) {
@ -135,14 +123,10 @@ pub fn parse_template(
}
/// Parse a code block. Returns `Some` if all of the input was consumed.
pub fn parse_block(
pub fn reparse_block(
prefix: &str,
src: &str,
end_pos: usize,
_: isize,
_: &[Green],
_: bool,
_: usize,
) -> Option<(Vec<Green>, bool, usize)> {
let mut p = Parser::with_prefix(prefix, src, TokenMode::Code);
if !p.at(&NodeKind::LeftBrace) {

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@ -2,7 +2,7 @@ use core::slice::SliceIndex;
use std::fmt::{self, Display, Formatter};
use std::mem;
use super::{Scanner, TokenMode, Tokens};
use super::{TokenMode, Tokens};
use crate::syntax::{ErrorPos, Green, GreenData, GreenNode, NodeKind};
/// A convenient token-based parser.
@ -30,11 +30,14 @@ pub struct Parser<'s> {
impl<'s> Parser<'s> {
/// Create a new parser for the source string.
pub fn new(src: &'s str, mode: TokenMode) -> Self {
Self::with_offset(src, mode, 0)
Self::with_prefix("", src, mode)
}
fn with_offset(src: &'s str, mode: TokenMode, offset: usize) -> Self {
let mut tokens = Tokens::new(src, mode, offset);
/// Create a new parser for the source string that is prefixed by some text
/// that does not need to be parsed but taken into account for column
/// calculation.
pub fn with_prefix(prefix: &str, src: &'s str, mode: TokenMode) -> Self {
let mut tokens = Tokens::with_prefix(prefix, src, mode);
let current = tokens.next();
Self {
tokens,
@ -49,13 +52,6 @@ impl<'s> Parser<'s> {
}
}
/// Create a new parser for the source string that is prefixed by some text
/// that does not need to be parsed but taken into account for column
/// calculation.
pub fn with_prefix(prefix: &str, src: &'s str, mode: TokenMode) -> Self {
Self::with_offset(src, mode, Scanner::new(prefix).column(prefix.len()))
}
/// End the parsing process and return the last child.
pub fn finish(self) -> Vec<Green> {
self.children
@ -218,7 +214,7 @@ impl<'s> Parser<'s> {
/// Determine the column index for the given byte index.
pub fn column(&self, index: usize) -> usize {
self.tokens.scanner().column(index)
self.tokens.column(index)
}
/// Continue parsing in a group.

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@ -10,21 +10,13 @@ pub struct Scanner<'s> {
/// The index at which the peekable character starts. Must be in bounds and
/// at a codepoint boundary to guarantee safety.
index: usize,
/// Offsets the indentation on the first line of the source.
column_offset: usize,
}
impl<'s> Scanner<'s> {
/// Create a new char scanner.
#[inline]
pub fn new(src: &'s str) -> Self {
Self { src, index: 0, column_offset: 0 }
}
/// Create a new char scanner with an offset for the first line indent.
#[inline]
pub fn with_indent_offset(src: &'s str, column_offset: usize) -> Self {
Self { src, index: 0, column_offset }
Self { src, index: 0 }
}
/// Whether the end of the string is reached.
@ -177,30 +169,6 @@ impl<'s> Scanner<'s> {
// optimized away in some cases.
self.src.get(start .. self.index).unwrap_or_default()
}
/// The column index of a given index in the source string.
#[inline]
pub fn column(&self, index: usize) -> usize {
let mut apply_offset = false;
let res = self.src[.. index]
.char_indices()
.rev()
.take_while(|&(_, c)| !is_newline(c))
.inspect(|&(i, _)| {
if i == 0 {
apply_offset = true
}
})
.count();
// The loop is never executed if the slice is empty, but we are of
// course still at the start of the first line.
if self.src[.. index].len() == 0 {
apply_offset = true;
}
if apply_offset { res + self.column_offset } else { res }
}
}
/// Whether this character denotes a newline.

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@ -11,9 +11,14 @@ use crate::util::EcoString;
/// An iterator over the tokens of a string of source code.
pub struct Tokens<'s> {
/// The underlying scanner.
s: Scanner<'s>,
/// The mode the scanner is in. This determines what tokens it recognizes.
mode: TokenMode,
/// Whether the last token has been terminated.
terminated: bool,
/// Offsets the indentation on the first line of the source.
column_offset: usize,
}
/// What kind of tokens to emit.
@ -28,11 +33,19 @@ pub enum TokenMode {
impl<'s> Tokens<'s> {
/// Create a new token iterator with the given mode.
#[inline]
pub fn new(src: &'s str, mode: TokenMode, offset: usize) -> Self {
pub fn new(src: &'s str, mode: TokenMode) -> Self {
Self::with_prefix("", src, mode)
}
/// Create a new token iterator with the given mode and a prefix to offset
/// column calculations.
#[inline]
pub fn with_prefix(prefix: &str, src: &'s str, mode: TokenMode) -> Self {
Self {
s: Scanner::with_indent_offset(src, offset),
s: Scanner::new(src),
mode,
terminated: true,
column_offset: column(prefix, prefix.len(), 0),
}
}
@ -74,6 +87,12 @@ impl<'s> Tokens<'s> {
pub fn terminated(&self) -> bool {
self.terminated
}
/// The column index of a given index in the source string.
#[inline]
pub fn column(&self, index: usize) -> usize {
column(self.s.src(), index, self.column_offset)
}
}
impl<'s> Iterator for Tokens<'s> {
@ -321,7 +340,7 @@ impl<'s> Tokens<'s> {
}
fn raw(&mut self) -> NodeKind {
let column = self.s.column(self.s.index() - 1);
let column = self.column(self.s.index() - 1);
let mut backticks = 1;
while self.s.eat_if('`') {
@ -574,6 +593,30 @@ fn keyword(ident: &str) -> Option<NodeKind> {
})
}
/// The column index of a given index in the source string, given a column offset for the first line.
#[inline]
fn column(string: &str, index: usize, offset: usize) -> usize {
let mut apply_offset = false;
let res = string[.. index]
.char_indices()
.rev()
.take_while(|&(_, c)| !is_newline(c))
.inspect(|&(i, _)| {
if i == 0 {
apply_offset = true
}
})
.count();
// The loop is never executed if the slice is empty, but we are of
// course still at the start of the first line.
if index == 0 {
apply_offset = true;
}
if apply_offset { res + offset } else { res }
}
#[cfg(test)]
#[allow(non_snake_case)]
mod tests {
@ -689,7 +732,7 @@ mod tests {
}};
(@$mode:ident: $src:expr => $($token:expr),*) => {{
let src = $src;
let found = Tokens::new(&src, $mode, 0).collect::<Vec<_>>();
let found = Tokens::new(&src, $mode).collect::<Vec<_>>();
let expected = vec![$($token.clone()),*];
check(&src, found, expected);
}};

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@ -60,7 +60,7 @@ impl Markup {
/// The markup nodes.
pub fn nodes(&self) -> impl Iterator<Item = MarkupNode> + '_ {
self.0.children().filter_map(|node| match node.kind() {
NodeKind::Space(n) if *n > 1 => Some(MarkupNode::Parbreak),
NodeKind::Space(2 ..) => Some(MarkupNode::Parbreak),
NodeKind::Space(_) => Some(MarkupNode::Space),
NodeKind::Linebreak => Some(MarkupNode::Linebreak),
NodeKind::Text(s) | NodeKind::TextInLine(s) => {

View File

@ -757,7 +757,7 @@ impl NodeKind {
/// Whether this node is `at_start` given the previous value of the property.
pub fn is_at_start(&self, prev: bool) -> bool {
match self {
Self::Space(n) if *n > 0 => true,
Self::Space(1 ..) => true,
Self::Space(_) | Self::LineComment | Self::BlockComment => prev,
_ => false,
}
@ -858,7 +858,7 @@ impl NodeKind {
Self::Include => "keyword `include`",
Self::From => "keyword `from`",
Self::Markup(_) => "markup",
Self::Space(n) if *n > 1 => "paragraph break",
Self::Space(2 ..) => "paragraph break",
Self::Space(_) => "space",
Self::Linebreak => "forced linebreak",
Self::Text(_) | Self::TextInLine(_) => "text",