1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 // Formatting and tools for comments.
13 use std::{self, borrow::Cow, iter};
15 use itertools::{multipeek, MultiPeek};
16 use syntax::source_map::Span;
19 use rewrite::RewriteContext;
20 use shape::{Indent, Shape};
21 use string::{rewrite_string, StringFormat};
22 use utils::{count_newlines, first_line_width, last_line_width, trim_left_preserve_layout};
23 use {ErrorKind, FormattingError};
25 fn is_custom_comment(comment: &str) -> bool {
26 if !comment.starts_with("//") {
28 } else if let Some(c) = comment.chars().nth(2) {
29 !c.is_alphanumeric() && !c.is_whitespace()
35 #[derive(Copy, Clone, PartialEq, Eq)]
36 pub enum CommentStyle<'a> {
46 fn custom_opener(s: &str) -> &str {
47 s.lines().next().map_or("", |first_line| {
50 .map_or(first_line, |space_index| &first_line[0..=space_index])
54 impl<'a> CommentStyle<'a> {
55 /// Returns true if the commenting style covers a line only.
56 pub fn is_line_comment(&self) -> bool {
58 CommentStyle::DoubleSlash
59 | CommentStyle::TripleSlash
61 | CommentStyle::Custom(_) => true,
66 /// Returns true if the commenting style can span over multiple lines.
67 pub fn is_block_comment(&self) -> bool {
69 CommentStyle::SingleBullet | CommentStyle::DoubleBullet | CommentStyle::Exclamation => {
76 /// Returns true if the commenting style is for documentation.
77 pub fn is_doc_comment(&self) -> bool {
79 CommentStyle::TripleSlash | CommentStyle::Doc => true,
84 pub fn opener(&self) -> &'a str {
86 CommentStyle::DoubleSlash => "// ",
87 CommentStyle::TripleSlash => "/// ",
88 CommentStyle::Doc => "//! ",
89 CommentStyle::SingleBullet => "/* ",
90 CommentStyle::DoubleBullet => "/** ",
91 CommentStyle::Exclamation => "/*! ",
92 CommentStyle::Custom(opener) => opener,
96 pub fn closer(&self) -> &'a str {
98 CommentStyle::DoubleSlash
99 | CommentStyle::TripleSlash
100 | CommentStyle::Custom(..)
101 | CommentStyle::Doc => "",
102 CommentStyle::DoubleBullet => " **/",
103 CommentStyle::SingleBullet | CommentStyle::Exclamation => " */",
107 pub fn line_start(&self) -> &'a str {
109 CommentStyle::DoubleSlash => "// ",
110 CommentStyle::TripleSlash => "/// ",
111 CommentStyle::Doc => "//! ",
112 CommentStyle::SingleBullet | CommentStyle::Exclamation => " * ",
113 CommentStyle::DoubleBullet => " ** ",
114 CommentStyle::Custom(opener) => opener,
118 pub fn to_str_tuplet(&self) -> (&'a str, &'a str, &'a str) {
119 (self.opener(), self.closer(), self.line_start())
123 fn comment_style(orig: &str, normalize_comments: bool) -> CommentStyle {
124 if !normalize_comments {
125 if orig.starts_with("/**") && !orig.starts_with("/**/") {
126 CommentStyle::DoubleBullet
127 } else if orig.starts_with("/*!") {
128 CommentStyle::Exclamation
129 } else if orig.starts_with("/*") {
130 CommentStyle::SingleBullet
131 } else if orig.starts_with("///") && orig.chars().nth(3).map_or(true, |c| c != '/') {
132 CommentStyle::TripleSlash
133 } else if orig.starts_with("//!") {
135 } else if is_custom_comment(orig) {
136 CommentStyle::Custom(custom_opener(orig))
138 CommentStyle::DoubleSlash
140 } else if (orig.starts_with("///") && orig.chars().nth(3).map_or(true, |c| c != '/'))
141 || (orig.starts_with("/**") && !orig.starts_with("/**/"))
143 CommentStyle::TripleSlash
144 } else if orig.starts_with("//!") || orig.starts_with("/*!") {
146 } else if is_custom_comment(orig) {
147 CommentStyle::Custom(custom_opener(orig))
149 CommentStyle::DoubleSlash
153 /// Combine `prev_str` and `next_str` into a single `String`. `span` may contain
154 /// comments between two strings. If there are such comments, then that will be
155 /// recovered. If `allow_extend` is true and there is no comment between the two
156 /// strings, then they will be put on a single line as long as doing so does not
157 /// exceed max width.
158 pub fn combine_strs_with_missing_comments(
159 context: &RewriteContext,
165 ) -> Option<String> {
167 "combine_strs_with_missing_comments `{}` `{}` {:?} {:?}",
175 String::with_capacity(prev_str.len() + next_str.len() + shape.indent.width() + 128);
176 result.push_str(prev_str);
177 let mut allow_one_line = !prev_str.contains('\n') && !next_str.contains('\n');
178 let first_sep = if prev_str.is_empty() || next_str.is_empty() {
183 let mut one_line_width =
184 last_line_width(prev_str) + first_line_width(next_str) + first_sep.len();
186 let config = context.config;
187 let indent = shape.indent;
188 let missing_comment = rewrite_missing_comment(span, shape, context)?;
190 if missing_comment.is_empty() {
191 if allow_extend && prev_str.len() + first_sep.len() + next_str.len() <= shape.width {
192 result.push_str(first_sep);
193 } else if !prev_str.is_empty() {
194 result.push_str(&indent.to_string_with_newline(config))
196 result.push_str(next_str);
200 // We have a missing comment between the first expression and the second expression.
202 // Peek the the original source code and find out whether there is a newline between the first
203 // expression and the second expression or the missing comment. We will preserve the original
204 // layout whenever possible.
205 let original_snippet = context.snippet(span);
206 let prefer_same_line = if let Some(pos) = original_snippet.find('/') {
207 !original_snippet[..pos].contains('\n')
209 !original_snippet.contains('\n')
212 one_line_width -= first_sep.len();
213 let first_sep = if prev_str.is_empty() || missing_comment.is_empty() {
216 let one_line_width = last_line_width(prev_str) + first_line_width(&missing_comment) + 1;
217 if prefer_same_line && one_line_width <= shape.width {
220 indent.to_string_with_newline(config)
223 result.push_str(&first_sep);
224 result.push_str(&missing_comment);
226 let second_sep = if missing_comment.is_empty() || next_str.is_empty() {
228 } else if missing_comment.starts_with("//") {
229 indent.to_string_with_newline(config)
231 one_line_width += missing_comment.len() + first_sep.len() + 1;
232 allow_one_line &= !missing_comment.starts_with("//") && !missing_comment.contains('\n');
233 if prefer_same_line && allow_one_line && one_line_width <= shape.width {
236 indent.to_string_with_newline(config)
239 result.push_str(&second_sep);
240 result.push_str(next_str);
245 pub fn rewrite_doc_comment(orig: &str, shape: Shape, config: &Config) -> Option<String> {
246 identify_comment(orig, false, shape, config, true)
249 pub fn rewrite_comment(
254 ) -> Option<String> {
255 identify_comment(orig, block_style, shape, config, false)
263 is_doc_comment: bool,
264 ) -> Option<String> {
265 let style = comment_style(orig, false);
267 // Computes the len of line taking into account a newline if the line is part of a paragraph.
268 fn compute_len(orig: &str, line: &str) -> usize {
269 if orig.len() > line.len() {
270 if orig.as_bytes()[line.len()] == b'\r' {
280 // Get the first group of line comments having the same commenting style.
282 // Returns a tuple with:
283 // - a boolean indicating if there is a blank line
284 // - a number indicating the size of the first group of comments
285 fn consume_same_line_comments(
290 let mut first_group_ending = 0;
293 for line in orig.lines() {
294 let trimmed_line = line.trim_left();
295 if trimmed_line.is_empty() {
298 } else if trimmed_line.starts_with(line_start)
299 || comment_style(trimmed_line, false) == style
301 first_group_ending += compute_len(&orig[first_group_ending..], line);
306 (hbl, first_group_ending)
309 let (has_bare_lines, first_group_ending) = match style {
310 CommentStyle::DoubleSlash | CommentStyle::TripleSlash | CommentStyle::Doc => {
311 let line_start = style.line_start().trim_left();
312 consume_same_line_comments(style, orig, line_start)
314 CommentStyle::Custom(opener) => {
315 let trimmed_opener = opener.trim_right();
316 consume_same_line_comments(style, orig, trimmed_opener)
318 // for a block comment, search for the closing symbol
319 CommentStyle::DoubleBullet | CommentStyle::SingleBullet | CommentStyle::Exclamation => {
320 let closer = style.closer().trim_left();
321 let mut closing_symbol_offset = 0;
323 let mut first = true;
324 for line in orig.lines() {
325 closing_symbol_offset += compute_len(&orig[closing_symbol_offset..], line);
326 let mut trimmed_line = line.trim_left();
327 if !trimmed_line.starts_with('*')
328 && !trimmed_line.starts_with("//")
329 && !trimmed_line.starts_with("/*")
334 // Remove opener from consideration when searching for closer
336 let opener = style.opener().trim_right();
337 trimmed_line = &trimmed_line[opener.len()..];
340 if trimmed_line.ends_with(closer) {
344 (hbl, closing_symbol_offset)
348 let (first_group, rest) = orig.split_at(first_group_ending);
349 let rewritten_first_group =
350 if !config.normalize_comments() && has_bare_lines && style.is_block_comment() {
351 trim_left_preserve_layout(first_group, shape.indent, config)?
352 } else if !config.normalize_comments()
353 && !config.wrap_comments()
354 && !config.format_doc_comments()
356 light_rewrite_comment(first_group, shape.indent, config, is_doc_comment)
358 rewrite_comment_inner(
364 is_doc_comment || style.is_doc_comment(),
368 Some(rewritten_first_group)
370 identify_comment(rest.trim_left(), block_style, shape, config, is_doc_comment).map(
374 rewritten_first_group,
375 // insert back the blank line
376 if has_bare_lines && style.is_line_comment() {
381 shape.indent.to_string(config),
389 /// Attributes for code blocks in rustdoc.
390 /// See https://doc.rust-lang.org/rustdoc/print.html#attributes
391 enum CodeBlockAttribute {
400 impl CodeBlockAttribute {
401 fn new(attribute: &str) -> CodeBlockAttribute {
403 "rust" | "" => CodeBlockAttribute::Rust,
404 "ignore" => CodeBlockAttribute::Ignore,
405 "text" => CodeBlockAttribute::Text,
406 "should_panic" => CodeBlockAttribute::ShouldPanic,
407 "no_run" => CodeBlockAttribute::NoRun,
408 "compile_fail" => CodeBlockAttribute::CompileFail,
409 _ => CodeBlockAttribute::Text,
414 /// Block that is formatted as an item.
416 /// An item starts with either a star `*` or a dash `-`. Different level of indentation are
417 /// handled by shrinking the shape accordingly.
418 struct ItemizedBlock {
419 /// the lines that are identified as part of an itemized block
421 /// the number of whitespaces up to the item sigil
423 /// the string that marks the start of an item
425 /// sequence of whitespaces to prefix new lines that are part of the item
430 /// Returns true if the line is formatted as an item
431 fn is_itemized_line(line: &str) -> bool {
432 let trimmed = line.trim_left();
433 trimmed.starts_with("* ") || trimmed.starts_with("- ")
436 /// Creates a new ItemizedBlock described with the given line.
437 /// The `is_itemized_line` needs to be called first.
438 fn new(line: &str) -> ItemizedBlock {
439 let space_to_sigil = line.chars().take_while(|c| c.is_whitespace()).count();
440 let indent = space_to_sigil + 2;
442 lines: vec![line[indent..].to_string()],
444 opener: line[..indent].to_string(),
445 line_start: " ".repeat(indent),
449 /// Returns a `StringFormat` used for formatting the content of an item
450 fn create_string_format<'a>(&'a self, fmt: &'a StringFormat) -> StringFormat<'a> {
456 shape: Shape::legacy(fmt.shape.width.saturating_sub(self.indent), Indent::empty()),
462 /// Returns true if the line is part of the current itemized block.
463 /// If it is, then it is added to the internal lines vec.
464 fn add_line(&mut self, line: &str) -> bool {
465 if !ItemizedBlock::is_itemized_line(line)
466 && self.indent <= line.chars().take_while(|c| c.is_whitespace()).count()
468 self.lines.push(line.to_string());
474 /// Returns the block as a string, with each line trimmed at the start.
475 fn trimmed_block_as_string(&self) -> String {
478 .map(|line| format!("{} ", line.trim_start()))
482 /// Returns the block as a string under its original form
483 fn original_block_as_string(&self) -> String {
486 .map(|line| format!("{}\n", line))
491 struct CommentRewrite<'a> {
493 code_block_buffer: String,
494 is_prev_line_multi_line: bool,
495 code_block_attr: Option<CodeBlockAttribute>,
496 item_block: Option<ItemizedBlock>,
497 comment_line_separator: String,
501 fmt: StringFormat<'a>,
508 impl<'a> CommentRewrite<'a> {
514 ) -> CommentRewrite<'a> {
515 let (opener, closer, line_start) = if block_style {
516 CommentStyle::SingleBullet.to_str_tuplet()
518 comment_style(orig, config.normalize_comments()).to_str_tuplet()
521 let max_chars = shape
523 .checked_sub(closer.len() + opener.len())
525 let indent_str = shape.indent.to_string_with_newline(config).to_string();
526 let fmt_indent = shape.indent + (opener.len() - line_start.len());
528 let mut cr = CommentRewrite {
529 result: String::with_capacity(orig.len() * 2),
530 code_block_buffer: String::with_capacity(128),
531 is_prev_line_multi_line: false,
532 code_block_attr: None,
534 comment_line_separator: format!("{}{}", indent_str, line_start),
544 shape: Shape::legacy(max_chars, fmt_indent),
549 opener: opener.to_owned(),
550 closer: closer.to_owned(),
551 line_start: line_start.to_owned(),
553 cr.result.push_str(opener);
557 fn join_block(s: &str, sep: &str) -> String {
558 let mut result = String::with_capacity(s.len() + 128);
559 let mut iter = s.lines().peekable();
560 while let Some(line) = iter.next() {
561 result.push_str(line);
562 result.push_str(match iter.peek() {
563 Some(next_line) if next_line.is_empty() => sep.trim_right(),
571 fn finish(mut self) -> String {
572 if !self.code_block_buffer.is_empty() {
573 // There is a code block that is not properly enclosed by backticks.
574 // We will leave them untouched.
575 self.result.push_str(&self.comment_line_separator);
576 self.result.push_str(&Self::join_block(
577 &trim_custom_comment_prefix(&self.code_block_buffer),
578 &self.comment_line_separator,
582 if let Some(ref ib) = self.item_block {
583 // the last few lines are part of an itemized block
584 self.fmt.shape = Shape::legacy(self.max_chars, self.fmt_indent);
585 let item_fmt = ib.create_string_format(&self.fmt);
586 self.result.push_str(&self.comment_line_separator);
587 self.result.push_str(&ib.opener);
588 match rewrite_string(
589 &ib.trimmed_block_as_string(),
591 self.max_chars.saturating_sub(ib.indent),
593 Some(s) => self.result.push_str(&Self::join_block(
595 &format!("{}{}", &self.comment_line_separator, ib.line_start),
597 None => self.result.push_str(&Self::join_block(
598 &ib.original_block_as_string(),
599 &self.comment_line_separator,
604 self.result.push_str(&self.closer);
605 if self.result.ends_with(&self.opener) && self.opener.ends_with(' ') {
618 has_leading_whitespace: bool,
620 let is_last = i == count_newlines(orig);
622 if let Some(ref mut ib) = self.item_block {
623 if ib.add_line(&line) {
626 self.is_prev_line_multi_line = false;
627 self.fmt.shape = Shape::legacy(self.max_chars, self.fmt_indent);
628 let item_fmt = ib.create_string_format(&self.fmt);
629 self.result.push_str(&self.comment_line_separator);
630 self.result.push_str(&ib.opener);
631 match rewrite_string(
632 &ib.trimmed_block_as_string(),
634 self.max_chars.saturating_sub(ib.indent),
636 Some(s) => self.result.push_str(&Self::join_block(
638 &format!("{}{}", &self.comment_line_separator, ib.line_start),
640 None => self.result.push_str(&Self::join_block(
641 &ib.original_block_as_string(),
642 &self.comment_line_separator,
645 } else if self.code_block_attr.is_some() {
646 if line.starts_with("```") {
647 let code_block = match self.code_block_attr.as_ref().unwrap() {
648 CodeBlockAttribute::Ignore | CodeBlockAttribute::Text => {
649 trim_custom_comment_prefix(&self.code_block_buffer)
651 _ if self.code_block_buffer.is_empty() => String::new(),
653 let mut config = self.fmt.config.clone();
654 config.set().wrap_comments(false);
655 match ::format_code_block(&self.code_block_buffer, &config) {
656 Some(ref s) => trim_custom_comment_prefix(&s.snippet),
657 None => trim_custom_comment_prefix(&self.code_block_buffer),
661 if !code_block.is_empty() {
662 self.result.push_str(&self.comment_line_separator);
664 .push_str(&Self::join_block(&code_block, &self.comment_line_separator));
666 self.code_block_buffer.clear();
667 self.result.push_str(&self.comment_line_separator);
668 self.result.push_str(line);
669 self.code_block_attr = None;
671 self.code_block_buffer
672 .push_str(&hide_sharp_behind_comment(line));
673 self.code_block_buffer.push('\n');
678 self.code_block_attr = None;
679 self.item_block = None;
680 if line.starts_with("```") {
681 self.code_block_attr = Some(CodeBlockAttribute::new(&line[3..]))
682 } else if self.fmt.config.wrap_comments() && ItemizedBlock::is_itemized_line(&line) {
683 let ib = ItemizedBlock::new(&line);
684 self.item_block = Some(ib);
688 if self.result == self.opener {
689 let force_leading_whitespace = &self.opener == "/* " && count_newlines(orig) == 0;
690 if !has_leading_whitespace && !force_leading_whitespace && self.result.ends_with(' ') {
696 } else if self.is_prev_line_multi_line && !line.is_empty() {
697 self.result.push(' ')
698 } else if is_last && line.is_empty() {
699 // trailing blank lines are unwanted
700 if !self.closer.is_empty() {
701 self.result.push_str(&self.indent_str);
705 self.result.push_str(&self.comment_line_separator);
706 if !has_leading_whitespace && self.result.ends_with(' ') {
711 if self.fmt.config.wrap_comments() && line.len() > self.fmt.shape.width && !has_url(line) {
712 match rewrite_string(line, &self.fmt, self.max_chars) {
714 self.is_prev_line_multi_line = s.contains('\n');
715 self.result.push_str(s);
717 None if self.is_prev_line_multi_line => {
718 // We failed to put the current `line` next to the previous `line`.
719 // Remove the trailing space, then start rewrite on the next line.
721 self.result.push_str(&self.comment_line_separator);
722 self.fmt.shape = Shape::legacy(self.max_chars, self.fmt_indent);
723 match rewrite_string(line, &self.fmt, self.max_chars) {
725 self.is_prev_line_multi_line = s.contains('\n');
726 self.result.push_str(s);
729 self.is_prev_line_multi_line = false;
730 self.result.push_str(line);
735 self.is_prev_line_multi_line = false;
736 self.result.push_str(line);
740 self.fmt.shape = if self.is_prev_line_multi_line {
742 let offset = 1 + last_line_width(&self.result) - self.line_start.len();
744 width: self.max_chars.saturating_sub(offset),
745 indent: self.fmt_indent,
746 offset: self.fmt.shape.offset + offset,
749 Shape::legacy(self.max_chars, self.fmt_indent)
752 if line.is_empty() && self.result.ends_with(' ') && !is_last {
753 // Remove space if this is an empty comment or a doc comment.
756 self.result.push_str(line);
757 self.fmt.shape = Shape::legacy(self.max_chars, self.fmt_indent);
758 self.is_prev_line_multi_line = false;
765 fn rewrite_comment_inner(
771 is_doc_comment: bool,
772 ) -> Option<String> {
773 let mut rewriter = CommentRewrite::new(orig, block_style, shape, config);
775 let line_breaks = count_newlines(orig.trim_right());
779 .map(|(i, mut line)| {
780 line = trim_right_unless_two_whitespaces(line.trim_left(), is_doc_comment);
782 if i == line_breaks && line.ends_with("*/") && !line.starts_with("//") {
783 line = line[..(line.len() - 2)].trim_right();
788 .map(|s| left_trim_comment_line(s, &style))
789 .map(|(line, has_leading_whitespace)| {
790 if orig.starts_with("/*") && line_breaks == 0 {
793 has_leading_whitespace || config.normalize_comments(),
796 (line, has_leading_whitespace || config.normalize_comments())
800 for (i, (line, has_leading_whitespace)) in lines.enumerate() {
801 if rewriter.handle_line(orig, i, line, has_leading_whitespace) {
806 Some(rewriter.finish())
809 const RUSTFMT_CUSTOM_COMMENT_PREFIX: &str = "//#### ";
811 fn hide_sharp_behind_comment(s: &str) -> Cow<str> {
812 if s.trim_left().starts_with("# ") {
813 Cow::from(format!("{}{}", RUSTFMT_CUSTOM_COMMENT_PREFIX, s))
819 fn trim_custom_comment_prefix(s: &str) -> String {
822 let left_trimmed = line.trim_left();
823 if left_trimmed.starts_with(RUSTFMT_CUSTOM_COMMENT_PREFIX) {
824 left_trimmed.trim_left_matches(RUSTFMT_CUSTOM_COMMENT_PREFIX)
833 /// Returns true if the given string MAY include URLs or alike.
834 fn has_url(s: &str) -> bool {
835 // This function may return false positive, but should get its job done in most cases.
836 s.contains("https://") || s.contains("http://") || s.contains("ftp://") || s.contains("file://")
839 /// Given the span, rewrite the missing comment inside it if available.
840 /// Note that the given span must only include comments (or leading/trailing whitespaces).
841 pub fn rewrite_missing_comment(
844 context: &RewriteContext,
845 ) -> Option<String> {
846 let missing_snippet = context.snippet(span);
847 let trimmed_snippet = missing_snippet.trim();
848 if !trimmed_snippet.is_empty() {
849 rewrite_comment(trimmed_snippet, false, shape, context.config)
855 /// Recover the missing comments in the specified span, if available.
856 /// The layout of the comments will be preserved as long as it does not break the code
857 /// and its total width does not exceed the max width.
858 pub fn recover_missing_comment_in_span(
861 context: &RewriteContext,
863 ) -> Option<String> {
864 let missing_comment = rewrite_missing_comment(span, shape, context)?;
865 if missing_comment.is_empty() {
868 let missing_snippet = context.snippet(span);
869 let pos = missing_snippet.find('/').unwrap_or(0);
871 let total_width = missing_comment.len() + used_width + 1;
872 let force_new_line_before_comment =
873 missing_snippet[..pos].contains('\n') || total_width > context.config.max_width();
874 let sep = if force_new_line_before_comment {
875 shape.indent.to_string_with_newline(context.config)
879 Some(format!("{}{}", sep, missing_comment))
883 /// Trim trailing whitespaces unless they consist of two or more whitespaces.
884 fn trim_right_unless_two_whitespaces(s: &str, is_doc_comment: bool) -> &str {
885 if is_doc_comment && s.ends_with(" ") {
892 /// Trims whitespace and aligns to indent, but otherwise does not change comments.
893 fn light_rewrite_comment(
897 is_doc_comment: bool,
899 let lines: Vec<&str> = orig
902 // This is basically just l.trim(), but in the case that a line starts
903 // with `*` we want to leave one space before it, so it aligns with the
905 let first_non_whitespace = l.find(|c| !char::is_whitespace(c));
906 let left_trimmed = if let Some(fnw) = first_non_whitespace {
907 if l.as_bytes()[fnw] == b'*' && fnw > 0 {
915 // Preserve markdown's double-space line break syntax in doc comment.
916 trim_right_unless_two_whitespaces(left_trimmed, is_doc_comment)
919 lines.join(&format!("\n{}", offset.to_string(config)))
922 /// Trims comment characters and possibly a single space from the left of a string.
923 /// Does not trim all whitespace. If a single space is trimmed from the left of the string,
924 /// this function returns true.
925 fn left_trim_comment_line<'a>(line: &'a str, style: &CommentStyle) -> (&'a str, bool) {
926 if line.starts_with("//! ")
927 || line.starts_with("/// ")
928 || line.starts_with("/*! ")
929 || line.starts_with("/** ")
932 } else if let CommentStyle::Custom(opener) = *style {
933 if line.starts_with(opener) {
934 (&line[opener.len()..], true)
936 (&line[opener.trim_right().len()..], false)
938 } else if line.starts_with("/* ")
939 || line.starts_with("// ")
940 || line.starts_with("//!")
941 || line.starts_with("///")
942 || line.starts_with("** ")
943 || line.starts_with("/*!")
944 || (line.starts_with("/**") && !line.starts_with("/**/"))
946 (&line[3..], line.chars().nth(2).unwrap() == ' ')
947 } else if line.starts_with("/*")
948 || line.starts_with("* ")
949 || line.starts_with("//")
950 || line.starts_with("**")
952 (&line[2..], line.chars().nth(1).unwrap() == ' ')
953 } else if line.starts_with('*') {
956 (line, line.starts_with(' '))
960 pub trait FindUncommented {
961 fn find_uncommented(&self, pat: &str) -> Option<usize>;
964 impl FindUncommented for str {
965 fn find_uncommented(&self, pat: &str) -> Option<usize> {
966 let mut needle_iter = pat.chars();
967 for (kind, (i, b)) in CharClasses::new(self.char_indices()) {
968 match needle_iter.next() {
970 return Some(i - pat.len());
972 Some(c) => match kind {
973 FullCodeCharKind::Normal | FullCodeCharKind::InString if b == c => {}
975 needle_iter = pat.chars();
981 // Handle case where the pattern is a suffix of the search string
982 match needle_iter.next() {
984 None => Some(self.len() - pat.len()),
989 // Returns the first byte position after the first comment. The given string
990 // is expected to be prefixed by a comment, including delimiters.
991 // Good: "/* /* inner */ outer */ code();"
992 // Bad: "code(); // hello\n world!"
993 pub fn find_comment_end(s: &str) -> Option<usize> {
994 let mut iter = CharClasses::new(s.char_indices());
995 for (kind, (i, _c)) in &mut iter {
996 if kind == FullCodeCharKind::Normal || kind == FullCodeCharKind::InString {
1001 // Handle case where the comment ends at the end of s.
1002 if iter.status == CharClassesStatus::Normal {
1009 /// Returns true if text contains any comment.
1010 pub fn contains_comment(text: &str) -> bool {
1011 CharClasses::new(text.chars()).any(|(kind, _)| kind.is_comment())
1014 pub struct CharClasses<T>
1020 status: CharClassesStatus,
1023 pub trait RichChar {
1024 fn get_char(&self) -> char;
1027 impl RichChar for char {
1028 fn get_char(&self) -> char {
1033 impl RichChar for (usize, char) {
1034 fn get_char(&self) -> char {
1039 #[derive(PartialEq, Eq, Debug, Clone, Copy)]
1040 enum CharClassesStatus {
1045 RawStringPrefix(u32),
1046 RawStringSuffix(u32),
1049 // The u32 is the nesting deepness of the comment
1051 // Status when the '/' has been consumed, but not yet the '*', deepness is
1052 // the new deepness (after the comment opening).
1053 BlockCommentOpening(u32),
1054 // Status when the '*' has been consumed, but not yet the '/', deepness is
1055 // the new deepness (after the comment closing).
1056 BlockCommentClosing(u32),
1060 /// Distinguish between functional part of code and comments
1061 #[derive(PartialEq, Eq, Debug, Clone, Copy)]
1062 pub enum CodeCharKind {
1067 /// Distinguish between functional part of code and comments,
1068 /// describing opening and closing of comments for ease when chunking
1069 /// code from tagged characters
1070 #[derive(PartialEq, Eq, Debug, Clone, Copy)]
1071 pub enum FullCodeCharKind {
1073 /// The first character of a comment, there is only one for a comment (always '/')
1075 /// Any character inside a comment including the second character of comment
1076 /// marks ("//", "/*")
1078 /// Last character of a comment, '\n' for a line comment, '/' for a block comment.
1080 /// Start of a mutlitine string
1082 /// End of a mutlitine string
1084 /// Inside a string.
1088 impl FullCodeCharKind {
1089 pub fn is_comment(self) -> bool {
1091 FullCodeCharKind::StartComment
1092 | FullCodeCharKind::InComment
1093 | FullCodeCharKind::EndComment => true,
1098 pub fn is_string(self) -> bool {
1099 self == FullCodeCharKind::InString || self == FullCodeCharKind::StartString
1102 fn to_codecharkind(self) -> CodeCharKind {
1103 if self.is_comment() {
1104 CodeCharKind::Comment
1106 CodeCharKind::Normal
1111 impl<T> CharClasses<T>
1116 pub fn new(base: T) -> CharClasses<T> {
1118 base: multipeek(base),
1119 status: CharClassesStatus::Normal,
1124 fn is_raw_string_suffix<T>(iter: &mut MultiPeek<T>, count: u32) -> bool
1131 Some(c) if c.get_char() == '#' => continue,
1138 impl<T> Iterator for CharClasses<T>
1143 type Item = (FullCodeCharKind, T::Item);
1145 fn next(&mut self) -> Option<(FullCodeCharKind, T::Item)> {
1146 let item = self.base.next()?;
1147 let chr = item.get_char();
1148 let mut char_kind = FullCodeCharKind::Normal;
1149 self.status = match self.status {
1150 CharClassesStatus::LitRawString(sharps) => {
1151 char_kind = FullCodeCharKind::InString;
1155 char_kind = FullCodeCharKind::Normal;
1156 CharClassesStatus::Normal
1157 } else if is_raw_string_suffix(&mut self.base, sharps) {
1158 CharClassesStatus::RawStringSuffix(sharps)
1160 CharClassesStatus::LitRawString(sharps)
1163 _ => CharClassesStatus::LitRawString(sharps),
1166 CharClassesStatus::RawStringPrefix(sharps) => {
1167 char_kind = FullCodeCharKind::InString;
1169 '#' => CharClassesStatus::RawStringPrefix(sharps + 1),
1170 '"' => CharClassesStatus::LitRawString(sharps),
1171 _ => CharClassesStatus::Normal, // Unreachable.
1174 CharClassesStatus::RawStringSuffix(sharps) => {
1178 CharClassesStatus::Normal
1180 char_kind = FullCodeCharKind::InString;
1181 CharClassesStatus::RawStringSuffix(sharps - 1)
1184 _ => CharClassesStatus::Normal, // Unreachable
1187 CharClassesStatus::LitString => {
1188 char_kind = FullCodeCharKind::InString;
1190 '"' => CharClassesStatus::Normal,
1191 '\\' => CharClassesStatus::LitStringEscape,
1192 _ => CharClassesStatus::LitString,
1195 CharClassesStatus::LitStringEscape => {
1196 char_kind = FullCodeCharKind::InString;
1197 CharClassesStatus::LitString
1199 CharClassesStatus::LitChar => match chr {
1200 '\\' => CharClassesStatus::LitCharEscape,
1201 '\'' => CharClassesStatus::Normal,
1202 _ => CharClassesStatus::LitChar,
1204 CharClassesStatus::LitCharEscape => CharClassesStatus::LitChar,
1205 CharClassesStatus::Normal => match chr {
1206 'r' => match self.base.peek().map(|c| c.get_char()) {
1207 Some('#') | Some('"') => {
1208 char_kind = FullCodeCharKind::InString;
1209 CharClassesStatus::RawStringPrefix(0)
1211 _ => CharClassesStatus::Normal,
1214 char_kind = FullCodeCharKind::InString;
1215 CharClassesStatus::LitString
1218 // HACK: Work around mut borrow.
1219 match self.base.peek() {
1220 Some(next) if next.get_char() == '\\' => {
1221 self.status = CharClassesStatus::LitChar;
1222 return Some((char_kind, item));
1227 match self.base.peek() {
1228 Some(next) if next.get_char() == '\'' => CharClassesStatus::LitChar,
1229 _ => CharClassesStatus::Normal,
1232 '/' => match self.base.peek() {
1233 Some(next) if next.get_char() == '*' => {
1234 self.status = CharClassesStatus::BlockCommentOpening(1);
1235 return Some((FullCodeCharKind::StartComment, item));
1237 Some(next) if next.get_char() == '/' => {
1238 self.status = CharClassesStatus::LineComment;
1239 return Some((FullCodeCharKind::StartComment, item));
1241 _ => CharClassesStatus::Normal,
1243 _ => CharClassesStatus::Normal,
1245 CharClassesStatus::BlockComment(deepness) => {
1246 assert_ne!(deepness, 0);
1247 self.status = match self.base.peek() {
1248 Some(next) if next.get_char() == '/' && chr == '*' => {
1249 CharClassesStatus::BlockCommentClosing(deepness - 1)
1251 Some(next) if next.get_char() == '*' && chr == '/' => {
1252 CharClassesStatus::BlockCommentOpening(deepness + 1)
1254 _ => CharClassesStatus::BlockComment(deepness),
1256 return Some((FullCodeCharKind::InComment, item));
1258 CharClassesStatus::BlockCommentOpening(deepness) => {
1259 assert_eq!(chr, '*');
1260 self.status = CharClassesStatus::BlockComment(deepness);
1261 return Some((FullCodeCharKind::InComment, item));
1263 CharClassesStatus::BlockCommentClosing(deepness) => {
1264 assert_eq!(chr, '/');
1266 self.status = CharClassesStatus::Normal;
1267 return Some((FullCodeCharKind::EndComment, item));
1269 self.status = CharClassesStatus::BlockComment(deepness);
1270 return Some((FullCodeCharKind::InComment, item));
1273 CharClassesStatus::LineComment => match chr {
1275 self.status = CharClassesStatus::Normal;
1276 return Some((FullCodeCharKind::EndComment, item));
1279 self.status = CharClassesStatus::LineComment;
1280 return Some((FullCodeCharKind::InComment, item));
1284 Some((char_kind, item))
1288 /// An iterator over the lines of a string, paired with the char kind at the
1289 /// end of the line.
1290 pub struct LineClasses<'a> {
1291 base: iter::Peekable<CharClasses<std::str::Chars<'a>>>,
1292 kind: FullCodeCharKind,
1295 impl<'a> LineClasses<'a> {
1296 pub fn new(s: &'a str) -> Self {
1298 base: CharClasses::new(s.chars()).peekable(),
1299 kind: FullCodeCharKind::Normal,
1304 impl<'a> Iterator for LineClasses<'a> {
1305 type Item = (FullCodeCharKind, String);
1307 fn next(&mut self) -> Option<Self::Item> {
1310 let mut line = String::new();
1312 let start_class = match self.base.peek() {
1313 Some((kind, _)) => *kind,
1314 None => FullCodeCharKind::Normal,
1317 while let Some((kind, c)) = self.base.next() {
1319 self.kind = match (start_class, kind) {
1320 (FullCodeCharKind::Normal, FullCodeCharKind::InString) => {
1321 FullCodeCharKind::StartString
1323 (FullCodeCharKind::InString, FullCodeCharKind::Normal) => {
1324 FullCodeCharKind::EndString
1334 Some((self.kind, line))
1338 /// Iterator over functional and commented parts of a string. Any part of a string is either
1339 /// functional code, either *one* block comment, either *one* line comment. Whitespace between
1340 /// comments is functional code. Line comments contain their ending newlines.
1341 struct UngroupedCommentCodeSlices<'a> {
1343 iter: iter::Peekable<CharClasses<std::str::CharIndices<'a>>>,
1346 impl<'a> UngroupedCommentCodeSlices<'a> {
1347 fn new(code: &'a str) -> UngroupedCommentCodeSlices<'a> {
1348 UngroupedCommentCodeSlices {
1350 iter: CharClasses::new(code.char_indices()).peekable(),
1355 impl<'a> Iterator for UngroupedCommentCodeSlices<'a> {
1356 type Item = (CodeCharKind, usize, &'a str);
1358 fn next(&mut self) -> Option<Self::Item> {
1359 let (kind, (start_idx, _)) = self.iter.next()?;
1361 FullCodeCharKind::Normal | FullCodeCharKind::InString => {
1362 // Consume all the Normal code
1363 while let Some(&(char_kind, _)) = self.iter.peek() {
1364 if char_kind.is_comment() {
1367 let _ = self.iter.next();
1370 FullCodeCharKind::StartComment => {
1371 // Consume the whole comment
1372 while let Some((FullCodeCharKind::InComment, (_, _))) = self.iter.next() {}
1376 let slice = match self.iter.peek() {
1377 Some(&(_, (end_idx, _))) => &self.slice[start_idx..end_idx],
1378 None => &self.slice[start_idx..],
1381 if kind.is_comment() {
1382 CodeCharKind::Comment
1384 CodeCharKind::Normal
1392 /// Iterator over an alternating sequence of functional and commented parts of
1393 /// a string. The first item is always a, possibly zero length, subslice of
1394 /// functional text. Line style comments contain their ending newlines.
1395 pub struct CommentCodeSlices<'a> {
1397 last_slice_kind: CodeCharKind,
1398 last_slice_end: usize,
1401 impl<'a> CommentCodeSlices<'a> {
1402 pub fn new(slice: &'a str) -> CommentCodeSlices<'a> {
1405 last_slice_kind: CodeCharKind::Comment,
1411 impl<'a> Iterator for CommentCodeSlices<'a> {
1412 type Item = (CodeCharKind, usize, &'a str);
1414 fn next(&mut self) -> Option<Self::Item> {
1415 if self.last_slice_end == self.slice.len() {
1419 let mut sub_slice_end = self.last_slice_end;
1420 let mut first_whitespace = None;
1421 let subslice = &self.slice[self.last_slice_end..];
1422 let mut iter = CharClasses::new(subslice.char_indices());
1424 for (kind, (i, c)) in &mut iter {
1425 let is_comment_connector = self.last_slice_kind == CodeCharKind::Normal
1426 && &subslice[..2] == "//"
1427 && [' ', '\t'].contains(&c);
1429 if is_comment_connector && first_whitespace.is_none() {
1430 first_whitespace = Some(i);
1433 if kind.to_codecharkind() == self.last_slice_kind && !is_comment_connector {
1434 let last_index = match first_whitespace {
1438 sub_slice_end = self.last_slice_end + last_index;
1442 if !is_comment_connector {
1443 first_whitespace = None;
1447 if let (None, true) = (iter.next(), sub_slice_end == self.last_slice_end) {
1448 // This was the last subslice.
1449 sub_slice_end = match first_whitespace {
1450 Some(i) => self.last_slice_end + i,
1451 None => self.slice.len(),
1455 let kind = match self.last_slice_kind {
1456 CodeCharKind::Comment => CodeCharKind::Normal,
1457 CodeCharKind::Normal => CodeCharKind::Comment,
1461 self.last_slice_end,
1462 &self.slice[self.last_slice_end..sub_slice_end],
1464 self.last_slice_end = sub_slice_end;
1465 self.last_slice_kind = kind;
1471 /// Checks is `new` didn't miss any comment from `span`, if it removed any, return previous text
1472 /// (if it fits in the width/offset, else return None), else return `new`
1473 pub fn recover_comment_removed(
1476 context: &RewriteContext,
1477 ) -> Option<String> {
1478 let snippet = context.snippet(span);
1479 if snippet != new && changed_comment_content(snippet, &new) {
1480 // We missed some comments. Warn and keep the original text.
1481 if context.config.error_on_unformatted() {
1482 context.report.append(
1483 context.source_map.span_to_filename(span).into(),
1484 vec![FormattingError::from_span(
1486 &context.source_map,
1487 ErrorKind::LostComment,
1491 Some(snippet.to_owned())
1497 pub fn filter_normal_code(code: &str) -> String {
1498 let mut buffer = String::with_capacity(code.len());
1499 LineClasses::new(code).for_each(|(kind, line)| match kind {
1500 FullCodeCharKind::Normal
1501 | FullCodeCharKind::StartString
1502 | FullCodeCharKind::InString
1503 | FullCodeCharKind::EndString => {
1504 buffer.push_str(&line);
1509 if !code.ends_with('\n') && buffer.ends_with('\n') {
1515 /// Return true if the two strings of code have the same payload of comments.
1516 /// The payload of comments is everything in the string except:
1517 /// - actual code (not comments)
1518 /// - comment start/end marks
1520 /// - '*' at the beginning of lines in block comments
1521 fn changed_comment_content(orig: &str, new: &str) -> bool {
1522 // Cannot write this as a fn since we cannot return types containing closures
1523 let code_comment_content = |code| {
1524 let slices = UngroupedCommentCodeSlices::new(code);
1526 .filter(|&(ref kind, _, _)| *kind == CodeCharKind::Comment)
1527 .flat_map(|(_, _, s)| CommentReducer::new(s))
1529 let res = code_comment_content(orig).ne(code_comment_content(new));
1531 "comment::changed_comment_content: {}\norig: '{}'\nnew: '{}'\nraw_old: {}\nraw_new: {}",
1535 code_comment_content(orig).collect::<String>(),
1536 code_comment_content(new).collect::<String>()
1541 /// Iterator over the 'payload' characters of a comment.
1542 /// It skips whitespace, comment start/end marks, and '*' at the beginning of lines.
1543 /// The comment must be one comment, ie not more than one start mark (no multiple line comments,
1545 struct CommentReducer<'a> {
1547 at_start_line: bool,
1548 iter: std::str::Chars<'a>,
1551 impl<'a> CommentReducer<'a> {
1552 fn new(comment: &'a str) -> CommentReducer<'a> {
1553 let is_block = comment.starts_with("/*");
1554 let comment = remove_comment_header(comment);
1557 at_start_line: false, // There are no supplementary '*' on the first line
1558 iter: comment.chars(),
1563 impl<'a> Iterator for CommentReducer<'a> {
1566 fn next(&mut self) -> Option<Self::Item> {
1568 let mut c = self.iter.next()?;
1569 if self.is_block && self.at_start_line {
1570 while c.is_whitespace() {
1571 c = self.iter.next()?;
1573 // Ignore leading '*'
1575 c = self.iter.next()?;
1577 } else if c == '\n' {
1578 self.at_start_line = true;
1580 if !c.is_whitespace() {
1587 fn remove_comment_header(comment: &str) -> &str {
1588 if comment.starts_with("///") || comment.starts_with("//!") {
1590 } else if comment.starts_with("//") {
1592 } else if (comment.starts_with("/**") && !comment.starts_with("/**/"))
1593 || comment.starts_with("/*!")
1595 &comment[3..comment.len() - 2]
1598 comment.starts_with("/*"),
1599 format!("string '{}' is not a comment", comment)
1601 &comment[2..comment.len() - 2]
1608 use shape::{Indent, Shape};
1612 let mut iter = CharClasses::new("//\n\n".chars());
1614 assert_eq!((FullCodeCharKind::StartComment, '/'), iter.next().unwrap());
1615 assert_eq!((FullCodeCharKind::InComment, '/'), iter.next().unwrap());
1616 assert_eq!((FullCodeCharKind::EndComment, '\n'), iter.next().unwrap());
1617 assert_eq!((FullCodeCharKind::Normal, '\n'), iter.next().unwrap());
1618 assert_eq!(None, iter.next());
1622 fn comment_code_slices() {
1623 let input = "code(); /* test */ 1 + 1";
1624 let mut iter = CommentCodeSlices::new(input);
1626 assert_eq!((CodeCharKind::Normal, 0, "code(); "), iter.next().unwrap());
1628 (CodeCharKind::Comment, 8, "/* test */"),
1629 iter.next().unwrap()
1631 assert_eq!((CodeCharKind::Normal, 18, " 1 + 1"), iter.next().unwrap());
1632 assert_eq!(None, iter.next());
1636 fn comment_code_slices_two() {
1637 let input = "// comment\n test();";
1638 let mut iter = CommentCodeSlices::new(input);
1640 assert_eq!((CodeCharKind::Normal, 0, ""), iter.next().unwrap());
1642 (CodeCharKind::Comment, 0, "// comment\n"),
1643 iter.next().unwrap()
1646 (CodeCharKind::Normal, 11, " test();"),
1647 iter.next().unwrap()
1649 assert_eq!(None, iter.next());
1653 fn comment_code_slices_three() {
1654 let input = "1 // comment\n // comment2\n\n";
1655 let mut iter = CommentCodeSlices::new(input);
1657 assert_eq!((CodeCharKind::Normal, 0, "1 "), iter.next().unwrap());
1659 (CodeCharKind::Comment, 2, "// comment\n // comment2\n"),
1660 iter.next().unwrap()
1662 assert_eq!((CodeCharKind::Normal, 29, "\n"), iter.next().unwrap());
1663 assert_eq!(None, iter.next());
1668 fn format_doc_comments() {
1669 let mut wrap_normalize_config: ::config::Config = Default::default();
1670 wrap_normalize_config.set().wrap_comments(true);
1671 wrap_normalize_config.set().normalize_comments(true);
1673 let mut wrap_config: ::config::Config = Default::default();
1674 wrap_config.set().wrap_comments(true);
1676 let comment = rewrite_comment(" //test",
1678 Shape::legacy(100, Indent::new(0, 100)),
1679 &wrap_normalize_config).unwrap();
1680 assert_eq!("/* test */", comment);
1682 let comment = rewrite_comment("// comment on a",
1684 Shape::legacy(10, Indent::empty()),
1685 &wrap_normalize_config).unwrap();
1686 assert_eq!("// comment\n// on a", comment);
1688 let comment = rewrite_comment("// A multi line comment\n // between args.",
1690 Shape::legacy(60, Indent::new(0, 12)),
1691 &wrap_normalize_config).unwrap();
1692 assert_eq!("// A multi line comment\n // between args.", comment);
1694 let input = "// comment";
1697 let comment = rewrite_comment(input,
1699 Shape::legacy(9, Indent::new(0, 69)),
1700 &wrap_normalize_config).unwrap();
1701 assert_eq!(expected, comment);
1703 let comment = rewrite_comment("/* trimmed */",
1705 Shape::legacy(100, Indent::new(0, 100)),
1706 &wrap_normalize_config).unwrap();
1707 assert_eq!("/* trimmed */", comment);
1709 // check that different comment style are properly recognised
1710 let comment = rewrite_comment(r#"/// test1
1716 Shape::legacy(100, Indent::new(0, 0)),
1717 &wrap_normalize_config).unwrap();
1718 assert_eq!("/// test1\n/// test2\n// test3", comment);
1720 // check that the blank line marks the end of a commented paragraph
1721 let comment = rewrite_comment(r#"// test1
1725 Shape::legacy(100, Indent::new(0, 0)),
1726 &wrap_normalize_config).unwrap();
1727 assert_eq!("// test1\n\n// test2", comment);
1729 // check that the blank line marks the end of a custom-commented paragraph
1730 let comment = rewrite_comment(r#"//@ test1
1734 Shape::legacy(100, Indent::new(0, 0)),
1735 &wrap_normalize_config).unwrap();
1736 assert_eq!("//@ test1\n\n//@ test2", comment);
1738 // check that bare lines are just indented but left unchanged otherwise
1739 let comment = rewrite_comment(r#"// test1
1746 Shape::legacy(100, Indent::new(0, 0)),
1747 &wrap_config).unwrap();
1748 assert_eq!("// test1\n/*\n a bare line!\n\n another bare line!\n*/", comment);
1751 // This is probably intended to be a non-test fn, but it is not used. I'm
1752 // keeping it around unless it helps us test stuff.
1753 fn uncommented(text: &str) -> String {
1754 CharClasses::new(text.chars())
1755 .filter_map(|(s, c)| match s {
1756 FullCodeCharKind::Normal | FullCodeCharKind::InString => Some(c),
1763 fn test_uncommented() {
1764 assert_eq!(&uncommented("abc/*...*/"), "abc");
1766 &uncommented("// .... /* \n../* /* *** / */ */a/* // */c\n"),
1769 assert_eq!(&uncommented("abc \" /* */\" qsdf"), "abc \" /* */\" qsdf");
1773 fn test_contains_comment() {
1774 assert_eq!(contains_comment("abc"), false);
1775 assert_eq!(contains_comment("abc // qsdf"), true);
1776 assert_eq!(contains_comment("abc /* kqsdf"), true);
1777 assert_eq!(contains_comment("abc \" /* */\" qsdf"), false);
1781 fn test_find_uncommented() {
1782 fn check(haystack: &str, needle: &str, expected: Option<usize>) {
1783 assert_eq!(expected, haystack.find_uncommented(needle));
1786 check("/*/ */test", "test", Some(6));
1787 check("//test\ntest", "test", Some(7));
1788 check("/* comment only */", "whatever", None);
1790 "/* comment */ some text /* more commentary */ result",
1794 check("sup // sup", "p", Some(2));
1795 check("sup", "x", None);
1796 check(r#"π? /**/ π is nice!"#, r#"π is nice"#, Some(9));
1797 check("/*sup yo? \n sup*/ sup", "p", Some(20));
1798 check("hel/*lohello*/lo", "hello", None);
1799 check("acb", "ab", None);
1800 check(",/*A*/ ", ",", Some(0));
1801 check("abc", "abc", Some(0));
1802 check("/* abc */", "abc", None);
1803 check("/**/abc/* */", "abc", Some(4));
1804 check("\"/* abc */\"", "abc", Some(4));
1805 check("\"/* abc", "abc", Some(4));
1809 fn test_filter_normal_code() {
1812 println!("hello, world");
1815 assert_eq!(s, filter_normal_code(s));
1816 let s_with_comment = r#"
1819 println!("hello, world");
1822 assert_eq!(s, filter_normal_code(s_with_comment));