Auto merge of #29734 - Ryman:whitespace_consistency, r=Aatch

libsyntax: be more accepting of whitespace in lexer

Fixes #29590.

Perhaps this may need more thorough testing?

r? @Aatch
This commit is contained in:
bors 2016-03-07 20:06:17 -08:00
commit 8b7c3f20e8
9 changed files with 114 additions and 67 deletions

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@ -87,7 +87,7 @@ DEPS_serialize := std log
DEPS_term := std log
DEPS_test := std getopts serialize rbml term native:rust_test_helpers
DEPS_syntax := std term serialize log arena libc rustc_bitflags
DEPS_syntax := std term serialize log arena libc rustc_bitflags rustc_unicode
DEPS_syntax_ext := syntax fmt_macros
DEPS_rustc := syntax fmt_macros flate arena serialize getopts rbml rustc_front\

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@ -398,7 +398,7 @@ pub const UNICODE_VERSION: (u64, u64, u64) = (%s, %s, %s);
derived = load_properties("DerivedCoreProperties.txt", want_derived)
scripts = load_properties("Scripts.txt", [])
props = load_properties("PropList.txt",
["White_Space", "Join_Control", "Noncharacter_Code_Point"])
["White_Space", "Join_Control", "Noncharacter_Code_Point", "Pattern_White_Space"])
norm_props = load_properties("DerivedNormalizationProps.txt",
["Full_Composition_Exclusion"])
@ -408,7 +408,7 @@ pub const UNICODE_VERSION: (u64, u64, u64) = (%s, %s, %s);
# category tables
for (name, cat, pfuns) in ("general_category", gencats, ["N", "Cc"]), \
("derived_property", derived, want_derived), \
("property", props, ["White_Space"]):
("property", props, ["White_Space", "Pattern_White_Space"]):
emit_property_module(rf, name, cat, pfuns)
# normalizations and conversions module

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@ -51,3 +51,8 @@ pub mod str {
pub mod derived_property {
pub use tables::derived_property::{Cased, Case_Ignorable};
}
// For use in libsyntax
pub mod property {
pub use tables::property::Pattern_White_Space;
}

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@ -1180,6 +1180,15 @@ pub mod derived_property {
}
pub mod property {
pub const Pattern_White_Space_table: &'static [(char, char)] = &[
('\u{9}', '\u{d}'), ('\u{20}', '\u{20}'), ('\u{85}', '\u{85}'), ('\u{200e}', '\u{200f}'),
('\u{2028}', '\u{2029}')
];
pub fn Pattern_White_Space(c: char) -> bool {
super::bsearch_range_table(c, Pattern_White_Space_table)
}
pub const White_Space_table: &'static [(char, char)] = &[
('\u{9}', '\u{d}'), ('\u{20}', '\u{20}'), ('\u{85}', '\u{85}'), ('\u{a0}', '\u{a0}'),
('\u{1680}', '\u{1680}'), ('\u{2000}', '\u{200a}'), ('\u{2028}', '\u{2029}'), ('\u{202f}',

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@ -38,6 +38,7 @@ extern crate term;
extern crate libc;
#[macro_use] extern crate log;
#[macro_use] #[no_link] extern crate rustc_bitflags;
extern crate rustc_unicode;
extern crate serialize as rustc_serialize; // used by deriving

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@ -15,7 +15,7 @@ use codemap::{BytePos, CharPos, CodeMap, Pos};
use errors;
use parse::lexer::is_block_doc_comment;
use parse::lexer::{StringReader, TokenAndSpan};
use parse::lexer::{is_whitespace, Reader};
use parse::lexer::{is_pattern_whitespace, Reader};
use parse::lexer;
use print::pprust;
use str::char_at;
@ -153,7 +153,7 @@ fn push_blank_line_comment(rdr: &StringReader, comments: &mut Vec<Comment>) {
}
fn consume_whitespace_counting_blank_lines(rdr: &mut StringReader, comments: &mut Vec<Comment>) {
while is_whitespace(rdr.curr) && !rdr.is_eof() {
while is_pattern_whitespace(rdr.curr) && !rdr.is_eof() {
if rdr.col == CharPos(0) && rdr.curr_is('\n') {
push_blank_line_comment(rdr, &mut *comments);
}

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@ -16,6 +16,7 @@ use ext::tt::transcribe::tt_next_token;
use parse::token::str_to_ident;
use parse::token;
use str::char_at;
use rustc_unicode::property::Pattern_White_Space;
use std::borrow::Cow;
use std::char;
@ -546,10 +547,10 @@ impl<'a> StringReader<'a> {
let c = self.scan_comment();
debug!("scanning a comment {:?}", c);
c
}
c if is_whitespace(Some(c)) => {
},
c if is_pattern_whitespace(Some(c)) => {
let start_bpos = self.last_pos;
while is_whitespace(self.curr) {
while is_pattern_whitespace(self.curr) {
self.bump();
}
let c = Some(TokenAndSpan {
@ -1440,7 +1441,7 @@ impl<'a> StringReader<'a> {
}
fn consume_whitespace(&mut self) {
while is_whitespace(self.curr) && !self.is_eof() {
while is_pattern_whitespace(self.curr) && !self.is_eof() {
self.bump();
}
}
@ -1465,7 +1466,7 @@ impl<'a> StringReader<'a> {
}
fn consume_non_eol_whitespace(&mut self) {
while is_whitespace(self.curr) && !self.curr_is('\n') && !self.is_eof() {
while is_pattern_whitespace(self.curr) && !self.curr_is('\n') && !self.is_eof() {
self.bump();
}
}
@ -1596,11 +1597,10 @@ impl<'a> StringReader<'a> {
}
}
pub fn is_whitespace(c: Option<char>) -> bool {
match c.unwrap_or('\x00') { // None can be null for now... it's not whitespace
' ' | '\n' | '\t' | '\r' => true,
_ => false,
}
// This tests the character for the unicode property 'PATTERN_WHITE_SPACE' which
// is guaranteed to be forward compatible. http://unicode.org/reports/tr31/#R3
pub fn is_pattern_whitespace(c: Option<char>) -> bool {
c.map_or(false, Pattern_White_Space)
}
fn in_range(c: Option<char>, lo: char, hi: char) -> bool {

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@ -10,11 +10,11 @@
use ast;
use parse::{ParseSess,PResult,filemap_to_tts};
use parse::new_parser_from_source_str;
use parse::{lexer, new_parser_from_source_str};
use parse::parser::Parser;
use parse::token;
use ptr::P;
use str::char_at;
use std::iter::Peekable;
/// Map a string to tts, using a made-up filename:
pub fn string_to_tts(source_str: String) -> Vec<ast::TokenTree> {
@ -87,69 +87,62 @@ pub fn strs_to_idents(ids: Vec<&str> ) -> Vec<ast::Ident> {
/// Does the given string match the pattern? whitespace in the first string
/// may be deleted or replaced with other whitespace to match the pattern.
/// this function is Unicode-ignorant; fortunately, the careful design of
/// UTF-8 mitigates this ignorance. In particular, this function only collapses
/// sequences of \n, \r, ' ', and \t, but it should otherwise tolerate Unicode
/// chars. Unsurprisingly, it doesn't do NKF-normalization(?).
/// This function is relatively Unicode-ignorant; fortunately, the careful design
/// of UTF-8 mitigates this ignorance. It doesn't do NKF-normalization(?).
pub fn matches_codepattern(a : &str, b : &str) -> bool {
let mut idx_a = 0;
let mut idx_b = 0;
let mut a_iter = a.chars().peekable();
let mut b_iter = b.chars().peekable();
loop {
if idx_a == a.len() && idx_b == b.len() {
return true;
}
else if idx_a == a.len() {return false;}
else if idx_b == b.len() {
// maybe the stuff left in a is all ws?
if is_whitespace(char_at(a, idx_a)) {
return scan_for_non_ws_or_end(a,idx_a) == a.len();
} else {
return false;
let (a, b) = match (a_iter.peek(), b_iter.peek()) {
(None, None) => return true,
(None, _) => return false,
(Some(&a), None) => {
if is_pattern_whitespace(a) {
break // trailing whitespace check is out of loop for borrowck
} else {
return false
}
}
(Some(&a), Some(&b)) => (a, b)
};
if is_pattern_whitespace(a) && is_pattern_whitespace(b) {
// skip whitespace for a and b
scan_for_non_ws_or_end(&mut a_iter);
scan_for_non_ws_or_end(&mut b_iter);
} else if is_pattern_whitespace(a) {
// skip whitespace for a
scan_for_non_ws_or_end(&mut a_iter);
} else if a == b {
a_iter.next();
b_iter.next();
} else {
return false
}
// ws in both given and pattern:
else if is_whitespace(char_at(a, idx_a))
&& is_whitespace(char_at(b, idx_b)) {
idx_a = scan_for_non_ws_or_end(a,idx_a);
idx_b = scan_for_non_ws_or_end(b,idx_b);
}
// ws in given only:
else if is_whitespace(char_at(a, idx_a)) {
idx_a = scan_for_non_ws_or_end(a,idx_a);
}
// *don't* silently eat ws in expected only.
else if char_at(a, idx_a) == char_at(b, idx_b) {
idx_a += 1;
idx_b += 1;
}
else {
return false;
}
}
// check if a has *only* trailing whitespace
a_iter.all(is_pattern_whitespace)
}
/// Advances the given peekable `Iterator` until it reaches a non-whitespace character
fn scan_for_non_ws_or_end<I: Iterator<Item= char>>(iter: &mut Peekable<I>) {
while lexer::is_pattern_whitespace(iter.peek().cloned()) {
iter.next();
}
}
/// Given a string and an index, return the first usize >= idx
/// that is a non-ws-char or is outside of the legal range of
/// the string.
fn scan_for_non_ws_or_end(a : &str, idx: usize) -> usize {
let mut i = idx;
let len = a.len();
while (i < len) && (is_whitespace(char_at(a, i))) {
i += 1;
}
i
}
/// Copied from lexer.
pub fn is_whitespace(c: char) -> bool {
return c == ' ' || c == '\t' || c == '\r' || c == '\n';
pub fn is_pattern_whitespace(c: char) -> bool {
lexer::is_pattern_whitespace(Some(c))
}
#[cfg(test)]
mod tests {
use super::*;
#[test] fn eqmodws() {
#[test]
fn eqmodws() {
assert_eq!(matches_codepattern("",""),true);
assert_eq!(matches_codepattern("","a"),false);
assert_eq!(matches_codepattern("a",""),false);
@ -160,5 +153,22 @@ mod tests {
assert_eq!(matches_codepattern("a b","a b"),true);
assert_eq!(matches_codepattern("ab","a b"),false);
assert_eq!(matches_codepattern("a b","ab"),true);
assert_eq!(matches_codepattern(" a b","ab"),true);
}
#[test]
fn pattern_whitespace() {
assert_eq!(matches_codepattern("","\x0C"), false);
assert_eq!(matches_codepattern("a b ","a \u{0085}\n\t\r b"),true);
assert_eq!(matches_codepattern("a b","a \u{0085}\n\t\r b "),false);
}
#[test]
fn non_pattern_whitespace() {
// These have the property 'White_Space' but not 'Pattern_White_Space'
assert_eq!(matches_codepattern("a b","a\u{2002}b"), false);
assert_eq!(matches_codepattern("a b","a\u{2002}b"), false);
assert_eq!(matches_codepattern("\u{205F}a b","ab"), false);
assert_eq!(matches_codepattern("a \u{3000}b","ab"), false);
}
}

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@ -0,0 +1,22 @@
// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Beware editing: it has numerous whitespace characters which are important.
// It contains one ranges from the 'PATTERN_WHITE_SPACE' property outlined in
// http://unicode.org/Public/UNIDATA/PropList.txt
//
// The characters in the first expression of the assertion can be generated
// from: "4\u{0C}+\n\t\r7\t*\u{20}2\u{85}/\u{200E}3\u{200F}*\u{2028}2\u{2029}"
pub fn main() {
assert_eq!(4 +
7 * 2…/3*2, 4 + 7 * 2 / 3 * 2);
}