1 // Formatting and tools for comments.
3 use std::{self, borrow::Cow, iter};
5 use itertools::{multipeek, MultiPeek};
6 use lazy_static::lazy_static;
10 use crate::config::Config;
11 use crate::rewrite::RewriteContext;
12 use crate::shape::{Indent, Shape};
13 use crate::string::{rewrite_string, StringFormat};
15 count_newlines, first_line_width, last_line_width, trim_left_preserve_layout,
16 trimmed_last_line_width, unicode_str_width,
18 use crate::{ErrorKind, FormattingError};
21 /// A regex matching reference doc links.
26 /// /// [example]: this::is::a::link
28 static ref REFERENCE_LINK_URL: Regex = Regex::new(r"^\[.+\]\s?:").unwrap();
31 fn is_custom_comment(comment: &str) -> bool {
32 if !comment.starts_with("//") {
34 } else if let Some(c) = comment.chars().nth(2) {
35 !c.is_alphanumeric() && !c.is_whitespace()
41 #[derive(Copy, Clone, PartialEq, Eq)]
42 pub(crate) enum CommentStyle<'a> {
52 fn custom_opener(s: &str) -> &str {
53 s.lines().next().map_or("", |first_line| {
56 .map_or(first_line, |space_index| &first_line[0..=space_index])
60 impl<'a> CommentStyle<'a> {
61 /// Returns `true` if the commenting style covers a line only.
62 pub(crate) fn is_line_comment(&self) -> bool {
64 CommentStyle::DoubleSlash
65 | CommentStyle::TripleSlash
67 | CommentStyle::Custom(_) => true,
72 /// Returns `true` if the commenting style can span over multiple lines.
73 pub(crate) fn is_block_comment(&self) -> bool {
75 CommentStyle::SingleBullet | CommentStyle::DoubleBullet | CommentStyle::Exclamation => {
82 /// Returns `true` if the commenting style is for documentation.
83 pub(crate) fn is_doc_comment(&self) -> bool {
84 matches!(*self, CommentStyle::TripleSlash | CommentStyle::Doc)
87 pub(crate) fn opener(&self) -> &'a str {
89 CommentStyle::DoubleSlash => "// ",
90 CommentStyle::TripleSlash => "/// ",
91 CommentStyle::Doc => "//! ",
92 CommentStyle::SingleBullet => "/* ",
93 CommentStyle::DoubleBullet => "/** ",
94 CommentStyle::Exclamation => "/*! ",
95 CommentStyle::Custom(opener) => opener,
99 pub(crate) fn closer(&self) -> &'a str {
101 CommentStyle::DoubleSlash
102 | CommentStyle::TripleSlash
103 | CommentStyle::Custom(..)
104 | CommentStyle::Doc => "",
105 CommentStyle::SingleBullet | CommentStyle::DoubleBullet | CommentStyle::Exclamation => {
111 pub(crate) fn line_start(&self) -> &'a str {
113 CommentStyle::DoubleSlash => "// ",
114 CommentStyle::TripleSlash => "/// ",
115 CommentStyle::Doc => "//! ",
116 CommentStyle::SingleBullet | CommentStyle::DoubleBullet | CommentStyle::Exclamation => {
119 CommentStyle::Custom(opener) => opener,
123 pub(crate) fn to_str_tuplet(&self) -> (&'a str, &'a str, &'a str) {
124 (self.opener(), self.closer(), self.line_start())
128 pub(crate) fn comment_style(orig: &str, normalize_comments: bool) -> CommentStyle<'_> {
129 if !normalize_comments {
130 if orig.starts_with("/**") && !orig.starts_with("/**/") {
131 CommentStyle::DoubleBullet
132 } else if orig.starts_with("/*!") {
133 CommentStyle::Exclamation
134 } else if orig.starts_with("/*") {
135 CommentStyle::SingleBullet
136 } else if orig.starts_with("///") && orig.chars().nth(3).map_or(true, |c| c != '/') {
137 CommentStyle::TripleSlash
138 } else if orig.starts_with("//!") {
140 } else if is_custom_comment(orig) {
141 CommentStyle::Custom(custom_opener(orig))
143 CommentStyle::DoubleSlash
145 } else if (orig.starts_with("///") && orig.chars().nth(3).map_or(true, |c| c != '/'))
146 || (orig.starts_with("/**") && !orig.starts_with("/**/"))
148 CommentStyle::TripleSlash
149 } else if orig.starts_with("//!") || orig.starts_with("/*!") {
151 } else if is_custom_comment(orig) {
152 CommentStyle::Custom(custom_opener(orig))
154 CommentStyle::DoubleSlash
158 /// Returns true if the last line of the passed string finishes with a block-comment.
159 pub(crate) fn is_last_comment_block(s: &str) -> bool {
160 s.trim_end().ends_with("*/")
163 /// Combine `prev_str` and `next_str` into a single `String`. `span` may contain
164 /// comments between two strings. If there are such comments, then that will be
165 /// recovered. If `allow_extend` is true and there is no comment between the two
166 /// strings, then they will be put on a single line as long as doing so does not
167 /// exceed max width.
168 pub(crate) fn combine_strs_with_missing_comments(
169 context: &RewriteContext<'_>,
175 ) -> Option<String> {
177 "combine_strs_with_missing_comments `{}` `{}` {:?} {:?}",
185 String::with_capacity(prev_str.len() + next_str.len() + shape.indent.width() + 128);
186 result.push_str(prev_str);
187 let mut allow_one_line = !prev_str.contains('\n') && !next_str.contains('\n');
189 if prev_str.is_empty() || next_str.is_empty() || trimmed_last_line_width(prev_str) == 0 {
194 let mut one_line_width =
195 last_line_width(prev_str) + first_line_width(next_str) + first_sep.len();
197 let config = context.config;
198 let indent = shape.indent;
199 let missing_comment = rewrite_missing_comment(span, shape, context)?;
201 if missing_comment.is_empty() {
202 if allow_extend && one_line_width <= shape.width {
203 result.push_str(first_sep);
204 } else if !prev_str.is_empty() {
205 result.push_str(&indent.to_string_with_newline(config))
207 result.push_str(next_str);
211 // We have a missing comment between the first expression and the second expression.
213 // Peek the the original source code and find out whether there is a newline between the first
214 // expression and the second expression or the missing comment. We will preserve the original
215 // layout whenever possible.
216 let original_snippet = context.snippet(span);
217 let prefer_same_line = if let Some(pos) = original_snippet.find('/') {
218 !original_snippet[..pos].contains('\n')
220 !original_snippet.contains('\n')
223 one_line_width -= first_sep.len();
224 let first_sep = if prev_str.is_empty() || missing_comment.is_empty() {
227 let one_line_width = last_line_width(prev_str) + first_line_width(&missing_comment) + 1;
228 if prefer_same_line && one_line_width <= shape.width {
231 indent.to_string_with_newline(config)
234 result.push_str(&first_sep);
235 result.push_str(&missing_comment);
237 let second_sep = if missing_comment.is_empty() || next_str.is_empty() {
239 } else if missing_comment.starts_with("//") {
240 indent.to_string_with_newline(config)
242 one_line_width += missing_comment.len() + first_sep.len() + 1;
243 allow_one_line &= !missing_comment.starts_with("//") && !missing_comment.contains('\n');
244 if prefer_same_line && allow_one_line && one_line_width <= shape.width {
247 indent.to_string_with_newline(config)
250 result.push_str(&second_sep);
251 result.push_str(next_str);
256 pub(crate) fn rewrite_doc_comment(orig: &str, shape: Shape, config: &Config) -> Option<String> {
257 identify_comment(orig, false, shape, config, true)
260 pub(crate) fn rewrite_comment(
265 ) -> Option<String> {
266 identify_comment(orig, block_style, shape, config, false)
274 is_doc_comment: bool,
275 ) -> Option<String> {
276 let style = comment_style(orig, false);
278 // Computes the byte length of line taking into account a newline if the line is part of a
280 fn compute_len(orig: &str, line: &str) -> usize {
281 if orig.len() > line.len() {
282 if orig.as_bytes()[line.len()] == b'\r' {
292 // Get the first group of line comments having the same commenting style.
294 // Returns a tuple with:
295 // - a boolean indicating if there is a blank line
296 // - a number indicating the size of the first group of comments
297 fn consume_same_line_comments(
298 style: CommentStyle<'_>,
302 let mut first_group_ending = 0;
305 for line in orig.lines() {
306 let trimmed_line = line.trim_start();
307 if trimmed_line.is_empty() {
310 } else if trimmed_line.starts_with(line_start)
311 || comment_style(trimmed_line, false) == style
313 first_group_ending += compute_len(&orig[first_group_ending..], line);
318 (hbl, first_group_ending)
321 let (has_bare_lines, first_group_ending) = match style {
322 CommentStyle::DoubleSlash | CommentStyle::TripleSlash | CommentStyle::Doc => {
323 let line_start = style.line_start().trim_start();
324 consume_same_line_comments(style, orig, line_start)
326 CommentStyle::Custom(opener) => {
327 let trimmed_opener = opener.trim_end();
328 consume_same_line_comments(style, orig, trimmed_opener)
330 // for a block comment, search for the closing symbol
331 CommentStyle::DoubleBullet | CommentStyle::SingleBullet | CommentStyle::Exclamation => {
332 let closer = style.closer().trim_start();
333 let mut count = orig.matches(closer).count();
334 let mut closing_symbol_offset = 0;
336 let mut first = true;
337 for line in orig.lines() {
338 closing_symbol_offset += compute_len(&orig[closing_symbol_offset..], line);
339 let mut trimmed_line = line.trim_start();
340 if !trimmed_line.starts_with('*')
341 && !trimmed_line.starts_with("//")
342 && !trimmed_line.starts_with("/*")
347 // Remove opener from consideration when searching for closer
349 let opener = style.opener().trim_end();
350 trimmed_line = &trimmed_line[opener.len()..];
353 if trimmed_line.ends_with(closer) {
360 (hbl, closing_symbol_offset)
364 let (first_group, rest) = orig.split_at(first_group_ending);
365 let rewritten_first_group =
366 if !config.normalize_comments() && has_bare_lines && style.is_block_comment() {
367 trim_left_preserve_layout(first_group, shape.indent, config)?
368 } else if !config.normalize_comments()
369 && !config.wrap_comments()
370 && !config.format_code_in_doc_comments()
372 light_rewrite_comment(first_group, shape.indent, config, is_doc_comment)
374 rewrite_comment_inner(
380 is_doc_comment || style.is_doc_comment(),
384 Some(rewritten_first_group)
396 rewritten_first_group,
397 // insert back the blank line
398 if has_bare_lines && style.is_line_comment() {
403 shape.indent.to_string(config),
410 /// Enum indicating if the code block contains rust based on attributes
411 enum CodeBlockAttribute {
416 impl CodeBlockAttribute {
417 /// Parse comma separated attributes list. Return rust only if all
418 /// attributes are valid rust attributes
419 /// See <https://doc.rust-lang.org/rustdoc/print.html#attributes>
420 fn new(attributes: &str) -> CodeBlockAttribute {
421 for attribute in attributes.split(',') {
422 match attribute.trim() {
423 "" | "rust" | "should_panic" | "no_run" | "edition2015" | "edition2018"
424 | "edition2021" => (),
425 "ignore" | "compile_fail" | "text" => return CodeBlockAttribute::NotRust,
426 _ => return CodeBlockAttribute::NotRust,
429 CodeBlockAttribute::Rust
433 /// Block that is formatted as an item.
435 /// An item starts with either a star `*` or a dash `-`. Different level of indentation are
436 /// handled by shrinking the shape accordingly.
437 struct ItemizedBlock {
438 /// the lines that are identified as part of an itemized block
440 /// the number of whitespaces up to the item sigil
442 /// the string that marks the start of an item
444 /// sequence of whitespaces to prefix new lines that are part of the item
449 /// Returns `true` if the line is formatted as an item
450 fn is_itemized_line(line: &str) -> bool {
451 let trimmed = line.trim_start();
452 trimmed.starts_with("* ") || trimmed.starts_with("- ")
455 /// Creates a new ItemizedBlock described with the given line.
456 /// The `is_itemized_line` needs to be called first.
457 fn new(line: &str) -> ItemizedBlock {
458 let space_to_sigil = line.chars().take_while(|c| c.is_whitespace()).count();
459 let indent = space_to_sigil + 2;
461 lines: vec![line[indent..].to_string()],
463 opener: line[..indent].to_string(),
464 line_start: " ".repeat(indent),
468 /// Returns a `StringFormat` used for formatting the content of an item.
469 fn create_string_format<'a>(&'a self, fmt: &'a StringFormat<'_>) -> StringFormat<'a> {
475 shape: Shape::legacy(fmt.shape.width.saturating_sub(self.indent), Indent::empty()),
481 /// Returns `true` if the line is part of the current itemized block.
482 /// If it is, then it is added to the internal lines list.
483 fn add_line(&mut self, line: &str) -> bool {
484 if !ItemizedBlock::is_itemized_line(line)
485 && self.indent <= line.chars().take_while(|c| c.is_whitespace()).count()
487 self.lines.push(line.to_string());
493 /// Returns the block as a string, with each line trimmed at the start.
494 fn trimmed_block_as_string(&self) -> String {
497 .map(|line| format!("{} ", line.trim_start()))
501 /// Returns the block as a string under its original form.
502 fn original_block_as_string(&self) -> String {
503 self.lines.join("\n")
507 struct CommentRewrite<'a> {
509 code_block_buffer: String,
510 is_prev_line_multi_line: bool,
511 code_block_attr: Option<CodeBlockAttribute>,
512 item_block: Option<ItemizedBlock>,
513 comment_line_separator: String,
517 fmt: StringFormat<'a>,
522 style: CommentStyle<'a>,
525 impl<'a> CommentRewrite<'a> {
531 ) -> CommentRewrite<'a> {
532 let ((opener, closer, line_start), style) = if block_style {
534 CommentStyle::SingleBullet.to_str_tuplet(),
535 CommentStyle::SingleBullet,
538 let style = comment_style(orig, config.normalize_comments());
539 (style.to_str_tuplet(), style)
542 let max_width = shape
544 .checked_sub(closer.len() + opener.len())
546 let indent_str = shape.indent.to_string_with_newline(config).to_string();
548 let mut cr = CommentRewrite {
549 result: String::with_capacity(orig.len() * 2),
550 code_block_buffer: String::with_capacity(128),
551 is_prev_line_multi_line: false,
552 code_block_attr: None,
554 comment_line_separator: format!("{}{}", indent_str, line_start),
557 fmt_indent: shape.indent,
564 shape: Shape::legacy(max_width, shape.indent),
569 opener: opener.to_owned(),
570 closer: closer.to_owned(),
571 line_start: line_start.to_owned(),
574 cr.result.push_str(opener);
578 fn join_block(s: &str, sep: &str) -> String {
579 let mut result = String::with_capacity(s.len() + 128);
580 let mut iter = s.lines().peekable();
581 while let Some(line) = iter.next() {
582 result.push_str(line);
583 result.push_str(match iter.peek() {
584 Some(next_line) if next_line.is_empty() => sep.trim_end(),
592 /// Check if any characters were written to the result buffer after the start of the comment.
593 /// when calling [`CommentRewrite::new()`] the result buffer is initiazlied with the opening
594 /// characters for the comment.
595 fn buffer_contains_comment(&self) -> bool {
596 // if self.result.len() < self.opener.len() then an empty comment is in the buffer
597 // if self.result.len() > self.opener.len() then a non empty comment is in the buffer
598 self.result.len() != self.opener.len()
601 fn finish(mut self) -> String {
602 if !self.code_block_buffer.is_empty() {
603 // There is a code block that is not properly enclosed by backticks.
604 // We will leave them untouched.
605 self.result.push_str(&self.comment_line_separator);
606 self.result.push_str(&Self::join_block(
607 &trim_custom_comment_prefix(&self.code_block_buffer),
608 &self.comment_line_separator,
612 if let Some(ref ib) = self.item_block {
613 // the last few lines are part of an itemized block
614 self.fmt.shape = Shape::legacy(self.max_width, self.fmt_indent);
615 let item_fmt = ib.create_string_format(&self.fmt);
617 // only push a comment_line_separator for ItemizedBlocks if the comment is not empty
618 if self.buffer_contains_comment() {
619 self.result.push_str(&self.comment_line_separator);
622 self.result.push_str(&ib.opener);
623 match rewrite_string(
624 &ib.trimmed_block_as_string(),
626 self.max_width.saturating_sub(ib.indent),
628 Some(s) => self.result.push_str(&Self::join_block(
630 &format!("{}{}", self.comment_line_separator, ib.line_start),
632 None => self.result.push_str(&Self::join_block(
633 &ib.original_block_as_string(),
634 &self.comment_line_separator,
639 self.result.push_str(&self.closer);
640 if self.result.ends_with(&self.opener) && self.opener.ends_with(' ') {
653 has_leading_whitespace: bool,
655 let num_newlines = count_newlines(orig);
656 let is_last = i == num_newlines;
657 let needs_new_comment_line = if self.style.is_block_comment() {
658 num_newlines > 0 || self.buffer_contains_comment()
660 self.buffer_contains_comment()
663 if let Some(ref mut ib) = self.item_block {
664 if ib.add_line(line) {
667 self.is_prev_line_multi_line = false;
668 self.fmt.shape = Shape::legacy(self.max_width, self.fmt_indent);
669 let item_fmt = ib.create_string_format(&self.fmt);
671 // only push a comment_line_separator if we need to start a new comment line
672 if needs_new_comment_line {
673 self.result.push_str(&self.comment_line_separator);
676 self.result.push_str(&ib.opener);
677 match rewrite_string(
678 &ib.trimmed_block_as_string(),
680 self.max_width.saturating_sub(ib.indent),
682 Some(s) => self.result.push_str(&Self::join_block(
684 &format!("{}{}", self.comment_line_separator, ib.line_start),
686 None => self.result.push_str(&Self::join_block(
687 &ib.original_block_as_string(),
688 &self.comment_line_separator,
691 } else if self.code_block_attr.is_some() {
692 if line.starts_with("```") {
693 let code_block = match self.code_block_attr.as_ref().unwrap() {
694 CodeBlockAttribute::Rust
695 if self.fmt.config.format_code_in_doc_comments()
696 && !self.code_block_buffer.is_empty() =>
698 let mut config = self.fmt.config.clone();
699 config.set().wrap_comments(false);
701 crate::format_code_block(&self.code_block_buffer, &config, false)
703 trim_custom_comment_prefix(&s.snippet)
705 trim_custom_comment_prefix(&self.code_block_buffer)
708 _ => trim_custom_comment_prefix(&self.code_block_buffer),
710 if !code_block.is_empty() {
711 self.result.push_str(&self.comment_line_separator);
713 .push_str(&Self::join_block(&code_block, &self.comment_line_separator));
715 self.code_block_buffer.clear();
716 self.result.push_str(&self.comment_line_separator);
717 self.result.push_str(line);
718 self.code_block_attr = None;
720 self.code_block_buffer
721 .push_str(&hide_sharp_behind_comment(line));
722 self.code_block_buffer.push('\n');
727 self.code_block_attr = None;
728 self.item_block = None;
729 if let Some(stripped) = line.strip_prefix("```") {
730 self.code_block_attr = Some(CodeBlockAttribute::new(stripped))
731 } else if self.fmt.config.wrap_comments() && ItemizedBlock::is_itemized_line(line) {
732 let ib = ItemizedBlock::new(line);
733 self.item_block = Some(ib);
737 if self.result == self.opener {
738 let force_leading_whitespace = &self.opener == "/* " && count_newlines(orig) == 0;
739 if !has_leading_whitespace && !force_leading_whitespace && self.result.ends_with(' ') {
745 } else if self.is_prev_line_multi_line && !line.is_empty() {
746 self.result.push(' ')
747 } else if is_last && line.is_empty() {
748 // trailing blank lines are unwanted
749 if !self.closer.is_empty() {
750 self.result.push_str(&self.indent_str);
754 self.result.push_str(&self.comment_line_separator);
755 if !has_leading_whitespace && self.result.ends_with(' ') {
760 if self.fmt.config.wrap_comments()
761 && unicode_str_width(line) > self.fmt.shape.width
764 match rewrite_string(line, &self.fmt, self.max_width) {
766 self.is_prev_line_multi_line = s.contains('\n');
767 self.result.push_str(s);
769 None if self.is_prev_line_multi_line => {
770 // We failed to put the current `line` next to the previous `line`.
771 // Remove the trailing space, then start rewrite on the next line.
773 self.result.push_str(&self.comment_line_separator);
774 self.fmt.shape = Shape::legacy(self.max_width, self.fmt_indent);
775 match rewrite_string(line, &self.fmt, self.max_width) {
777 self.is_prev_line_multi_line = s.contains('\n');
778 self.result.push_str(s);
781 self.is_prev_line_multi_line = false;
782 self.result.push_str(line);
787 self.is_prev_line_multi_line = false;
788 self.result.push_str(line);
792 self.fmt.shape = if self.is_prev_line_multi_line {
794 let offset = 1 + last_line_width(&self.result) - self.line_start.len();
796 width: self.max_width.saturating_sub(offset),
797 indent: self.fmt_indent,
798 offset: self.fmt.shape.offset + offset,
801 Shape::legacy(self.max_width, self.fmt_indent)
804 if line.is_empty() && self.result.ends_with(' ') && !is_last {
805 // Remove space if this is an empty comment or a doc comment.
808 self.result.push_str(line);
809 self.fmt.shape = Shape::legacy(self.max_width, self.fmt_indent);
810 self.is_prev_line_multi_line = false;
817 fn rewrite_comment_inner(
820 style: CommentStyle<'_>,
823 is_doc_comment: bool,
824 ) -> Option<String> {
825 let mut rewriter = CommentRewrite::new(orig, block_style, shape, config);
827 let line_breaks = count_newlines(orig.trim_end());
831 .map(|(i, mut line)| {
832 line = trim_end_unless_two_whitespaces(line.trim_start(), is_doc_comment);
834 if i == line_breaks && line.ends_with("*/") && !line.starts_with("//") {
835 line = line[..(line.len() - 2)].trim_end();
840 .map(|s| left_trim_comment_line(s, &style))
841 .map(|(line, has_leading_whitespace)| {
842 if orig.starts_with("/*") && line_breaks == 0 {
845 has_leading_whitespace || config.normalize_comments(),
848 (line, has_leading_whitespace || config.normalize_comments())
852 for (i, (line, has_leading_whitespace)) in lines.enumerate() {
853 if rewriter.handle_line(orig, i, line, has_leading_whitespace) {
858 Some(rewriter.finish())
861 const RUSTFMT_CUSTOM_COMMENT_PREFIX: &str = "//#### ";
863 fn hide_sharp_behind_comment(s: &str) -> Cow<'_, str> {
864 let s_trimmed = s.trim();
865 if s_trimmed.starts_with("# ") || s_trimmed == "#" {
866 Cow::from(format!("{}{}", RUSTFMT_CUSTOM_COMMENT_PREFIX, s))
872 fn trim_custom_comment_prefix(s: &str) -> String {
875 let left_trimmed = line.trim_start();
876 if left_trimmed.starts_with(RUSTFMT_CUSTOM_COMMENT_PREFIX) {
877 left_trimmed.trim_start_matches(RUSTFMT_CUSTOM_COMMENT_PREFIX)
886 /// Returns `true` if the given string MAY include URLs or alike.
887 fn has_url(s: &str) -> bool {
888 // This function may return false positive, but should get its job done in most cases.
889 s.contains("https://")
890 || s.contains("http://")
891 || s.contains("ftp://")
892 || s.contains("file://")
893 || REFERENCE_LINK_URL.is_match(s)
896 /// Given the span, rewrite the missing comment inside it if available.
897 /// Note that the given span must only include comments (or leading/trailing whitespaces).
898 pub(crate) fn rewrite_missing_comment(
901 context: &RewriteContext<'_>,
902 ) -> Option<String> {
903 let missing_snippet = context.snippet(span);
904 let trimmed_snippet = missing_snippet.trim();
905 // check the span starts with a comment
906 let pos = trimmed_snippet.find('/');
907 if !trimmed_snippet.is_empty() && pos.is_some() {
908 rewrite_comment(trimmed_snippet, false, shape, context.config)
914 /// Recover the missing comments in the specified span, if available.
915 /// The layout of the comments will be preserved as long as it does not break the code
916 /// and its total width does not exceed the max width.
917 pub(crate) fn recover_missing_comment_in_span(
920 context: &RewriteContext<'_>,
922 ) -> Option<String> {
923 let missing_comment = rewrite_missing_comment(span, shape, context)?;
924 if missing_comment.is_empty() {
927 let missing_snippet = context.snippet(span);
928 let pos = missing_snippet.find('/')?;
930 let total_width = missing_comment.len() + used_width + 1;
931 let force_new_line_before_comment =
932 missing_snippet[..pos].contains('\n') || total_width > context.config.max_width();
933 let sep = if force_new_line_before_comment {
934 shape.indent.to_string_with_newline(context.config)
938 Some(format!("{}{}", sep, missing_comment))
942 /// Trim trailing whitespaces unless they consist of two or more whitespaces.
943 fn trim_end_unless_two_whitespaces(s: &str, is_doc_comment: bool) -> &str {
944 if is_doc_comment && s.ends_with(" ") {
951 /// Trims whitespace and aligns to indent, but otherwise does not change comments.
952 fn light_rewrite_comment(
956 is_doc_comment: bool,
958 let lines: Vec<&str> = orig
961 // This is basically just l.trim(), but in the case that a line starts
962 // with `*` we want to leave one space before it, so it aligns with the
964 let first_non_whitespace = l.find(|c| !char::is_whitespace(c));
965 let left_trimmed = if let Some(fnw) = first_non_whitespace {
966 if l.as_bytes()[fnw] == b'*' && fnw > 0 {
974 // Preserve markdown's double-space line break syntax in doc comment.
975 trim_end_unless_two_whitespaces(left_trimmed, is_doc_comment)
978 lines.join(&format!("\n{}", offset.to_string(config)))
981 /// Trims comment characters and possibly a single space from the left of a string.
982 /// Does not trim all whitespace. If a single space is trimmed from the left of the string,
983 /// this function returns true.
984 fn left_trim_comment_line<'a>(line: &'a str, style: &CommentStyle<'_>) -> (&'a str, bool) {
985 if line.starts_with("//! ")
986 || line.starts_with("/// ")
987 || line.starts_with("/*! ")
988 || line.starts_with("/** ")
991 } else if let CommentStyle::Custom(opener) = *style {
992 if let Some(stripped) = line.strip_prefix(opener) {
995 (&line[opener.trim_end().len()..], false)
997 } else if line.starts_with("/* ")
998 || line.starts_with("// ")
999 || line.starts_with("//!")
1000 || line.starts_with("///")
1001 || line.starts_with("** ")
1002 || line.starts_with("/*!")
1003 || (line.starts_with("/**") && !line.starts_with("/**/"))
1005 (&line[3..], line.chars().nth(2).unwrap() == ' ')
1006 } else if line.starts_with("/*")
1007 || line.starts_with("* ")
1008 || line.starts_with("//")
1009 || line.starts_with("**")
1011 (&line[2..], line.chars().nth(1).unwrap() == ' ')
1012 } else if let Some(stripped) = line.strip_prefix('*') {
1015 (line, line.starts_with(' '))
1019 pub(crate) trait FindUncommented {
1020 fn find_uncommented(&self, pat: &str) -> Option<usize>;
1021 fn find_last_uncommented(&self, pat: &str) -> Option<usize>;
1024 impl FindUncommented for str {
1025 fn find_uncommented(&self, pat: &str) -> Option<usize> {
1026 let mut needle_iter = pat.chars();
1027 for (kind, (i, b)) in CharClasses::new(self.char_indices()) {
1028 match needle_iter.next() {
1030 return Some(i - pat.len());
1032 Some(c) => match kind {
1033 FullCodeCharKind::Normal | FullCodeCharKind::InString if b == c => {}
1035 needle_iter = pat.chars();
1041 // Handle case where the pattern is a suffix of the search string
1042 match needle_iter.next() {
1044 None => Some(self.len() - pat.len()),
1048 fn find_last_uncommented(&self, pat: &str) -> Option<usize> {
1049 if let Some(left) = self.find_uncommented(pat) {
1050 let mut result = left;
1051 // add 1 to use find_last_uncommented for &str after pat
1052 while let Some(next) = self[(result + 1)..].find_last_uncommented(pat) {
1062 // Returns the first byte position after the first comment. The given string
1063 // is expected to be prefixed by a comment, including delimiters.
1064 // Good: `/* /* inner */ outer */ code();`
1065 // Bad: `code(); // hello\n world!`
1066 pub(crate) fn find_comment_end(s: &str) -> Option<usize> {
1067 let mut iter = CharClasses::new(s.char_indices());
1068 for (kind, (i, _c)) in &mut iter {
1069 if kind == FullCodeCharKind::Normal || kind == FullCodeCharKind::InString {
1074 // Handle case where the comment ends at the end of `s`.
1075 if iter.status == CharClassesStatus::Normal {
1082 /// Returns `true` if text contains any comment.
1083 pub(crate) fn contains_comment(text: &str) -> bool {
1084 CharClasses::new(text.chars()).any(|(kind, _)| kind.is_comment())
1087 pub(crate) struct CharClasses<T>
1093 status: CharClassesStatus,
1096 pub(crate) trait RichChar {
1097 fn get_char(&self) -> char;
1100 impl RichChar for char {
1101 fn get_char(&self) -> char {
1106 impl RichChar for (usize, char) {
1107 fn get_char(&self) -> char {
1112 #[derive(PartialEq, Eq, Debug, Clone, Copy)]
1113 enum CharClassesStatus {
1115 /// Character is within a string
1118 /// Character is within a raw string
1120 RawStringPrefix(u32),
1121 RawStringSuffix(u32),
1124 /// Character inside a block comment, with the integer indicating the nesting deepness of the
1127 /// Character inside a block-commented string, with the integer indicating the nesting deepness
1129 StringInBlockComment(u32),
1130 /// Status when the '/' has been consumed, but not yet the '*', deepness is
1131 /// the new deepness (after the comment opening).
1132 BlockCommentOpening(u32),
1133 /// Status when the '*' has been consumed, but not yet the '/', deepness is
1134 /// the new deepness (after the comment closing).
1135 BlockCommentClosing(u32),
1136 /// Character is within a line comment
1140 /// Distinguish between functional part of code and comments
1141 #[derive(PartialEq, Eq, Debug, Clone, Copy)]
1142 pub(crate) enum CodeCharKind {
1147 /// Distinguish between functional part of code and comments,
1148 /// describing opening and closing of comments for ease when chunking
1149 /// code from tagged characters
1150 #[derive(PartialEq, Eq, Debug, Clone, Copy)]
1151 pub(crate) enum FullCodeCharKind {
1153 /// The first character of a comment, there is only one for a comment (always '/')
1155 /// Any character inside a comment including the second character of comment
1156 /// marks ("//", "/*")
1158 /// Last character of a comment, '\n' for a line comment, '/' for a block comment.
1160 /// Start of a mutlitine string inside a comment
1161 StartStringCommented,
1162 /// End of a mutlitine string inside a comment
1164 /// Inside a commented string
1166 /// Start of a mutlitine string
1168 /// End of a mutlitine string
1170 /// Inside a string.
1174 impl FullCodeCharKind {
1175 pub(crate) fn is_comment(self) -> bool {
1177 FullCodeCharKind::StartComment
1178 | FullCodeCharKind::InComment
1179 | FullCodeCharKind::EndComment
1180 | FullCodeCharKind::StartStringCommented
1181 | FullCodeCharKind::InStringCommented
1182 | FullCodeCharKind::EndStringCommented => true,
1187 /// Returns true if the character is inside a comment
1188 pub(crate) fn inside_comment(self) -> bool {
1190 FullCodeCharKind::InComment
1191 | FullCodeCharKind::StartStringCommented
1192 | FullCodeCharKind::InStringCommented
1193 | FullCodeCharKind::EndStringCommented => true,
1198 pub(crate) fn is_string(self) -> bool {
1199 self == FullCodeCharKind::InString || self == FullCodeCharKind::StartString
1202 /// Returns true if the character is within a commented string
1203 pub(crate) fn is_commented_string(self) -> bool {
1204 self == FullCodeCharKind::InStringCommented
1205 || self == FullCodeCharKind::StartStringCommented
1208 fn to_codecharkind(self) -> CodeCharKind {
1209 if self.is_comment() {
1210 CodeCharKind::Comment
1212 CodeCharKind::Normal
1217 impl<T> CharClasses<T>
1222 pub(crate) fn new(base: T) -> CharClasses<T> {
1224 base: multipeek(base),
1225 status: CharClassesStatus::Normal,
1230 fn is_raw_string_suffix<T>(iter: &mut MultiPeek<T>, count: u32) -> bool
1237 Some(c) if c.get_char() == '#' => continue,
1244 impl<T> Iterator for CharClasses<T>
1249 type Item = (FullCodeCharKind, T::Item);
1251 fn next(&mut self) -> Option<(FullCodeCharKind, T::Item)> {
1252 let item = self.base.next()?;
1253 let chr = item.get_char();
1254 let mut char_kind = FullCodeCharKind::Normal;
1255 self.status = match self.status {
1256 CharClassesStatus::LitRawString(sharps) => {
1257 char_kind = FullCodeCharKind::InString;
1261 char_kind = FullCodeCharKind::Normal;
1262 CharClassesStatus::Normal
1263 } else if is_raw_string_suffix(&mut self.base, sharps) {
1264 CharClassesStatus::RawStringSuffix(sharps)
1266 CharClassesStatus::LitRawString(sharps)
1269 _ => CharClassesStatus::LitRawString(sharps),
1272 CharClassesStatus::RawStringPrefix(sharps) => {
1273 char_kind = FullCodeCharKind::InString;
1275 '#' => CharClassesStatus::RawStringPrefix(sharps + 1),
1276 '"' => CharClassesStatus::LitRawString(sharps),
1277 _ => CharClassesStatus::Normal, // Unreachable.
1280 CharClassesStatus::RawStringSuffix(sharps) => {
1284 CharClassesStatus::Normal
1286 char_kind = FullCodeCharKind::InString;
1287 CharClassesStatus::RawStringSuffix(sharps - 1)
1290 _ => CharClassesStatus::Normal, // Unreachable
1293 CharClassesStatus::LitString => {
1294 char_kind = FullCodeCharKind::InString;
1296 '"' => CharClassesStatus::Normal,
1297 '\\' => CharClassesStatus::LitStringEscape,
1298 _ => CharClassesStatus::LitString,
1301 CharClassesStatus::LitStringEscape => {
1302 char_kind = FullCodeCharKind::InString;
1303 CharClassesStatus::LitString
1305 CharClassesStatus::LitChar => match chr {
1306 '\\' => CharClassesStatus::LitCharEscape,
1307 '\'' => CharClassesStatus::Normal,
1308 _ => CharClassesStatus::LitChar,
1310 CharClassesStatus::LitCharEscape => CharClassesStatus::LitChar,
1311 CharClassesStatus::Normal => match chr {
1312 'r' => match self.base.peek().map(RichChar::get_char) {
1313 Some('#') | Some('"') => {
1314 char_kind = FullCodeCharKind::InString;
1315 CharClassesStatus::RawStringPrefix(0)
1317 _ => CharClassesStatus::Normal,
1320 char_kind = FullCodeCharKind::InString;
1321 CharClassesStatus::LitString
1324 // HACK: Work around mut borrow.
1325 match self.base.peek() {
1326 Some(next) if next.get_char() == '\\' => {
1327 self.status = CharClassesStatus::LitChar;
1328 return Some((char_kind, item));
1333 match self.base.peek() {
1334 Some(next) if next.get_char() == '\'' => CharClassesStatus::LitChar,
1335 _ => CharClassesStatus::Normal,
1338 '/' => match self.base.peek() {
1339 Some(next) if next.get_char() == '*' => {
1340 self.status = CharClassesStatus::BlockCommentOpening(1);
1341 return Some((FullCodeCharKind::StartComment, item));
1343 Some(next) if next.get_char() == '/' => {
1344 self.status = CharClassesStatus::LineComment;
1345 return Some((FullCodeCharKind::StartComment, item));
1347 _ => CharClassesStatus::Normal,
1349 _ => CharClassesStatus::Normal,
1351 CharClassesStatus::StringInBlockComment(deepness) => {
1352 char_kind = FullCodeCharKind::InStringCommented;
1354 CharClassesStatus::BlockComment(deepness)
1355 } else if chr == '*' && self.base.peek().map(RichChar::get_char) == Some('/') {
1356 char_kind = FullCodeCharKind::InComment;
1357 CharClassesStatus::BlockCommentClosing(deepness - 1)
1359 CharClassesStatus::StringInBlockComment(deepness)
1362 CharClassesStatus::BlockComment(deepness) => {
1363 assert_ne!(deepness, 0);
1364 char_kind = FullCodeCharKind::InComment;
1365 match self.base.peek() {
1366 Some(next) if next.get_char() == '/' && chr == '*' => {
1367 CharClassesStatus::BlockCommentClosing(deepness - 1)
1369 Some(next) if next.get_char() == '*' && chr == '/' => {
1370 CharClassesStatus::BlockCommentOpening(deepness + 1)
1372 _ if chr == '"' => CharClassesStatus::StringInBlockComment(deepness),
1376 CharClassesStatus::BlockCommentOpening(deepness) => {
1377 assert_eq!(chr, '*');
1378 self.status = CharClassesStatus::BlockComment(deepness);
1379 return Some((FullCodeCharKind::InComment, item));
1381 CharClassesStatus::BlockCommentClosing(deepness) => {
1382 assert_eq!(chr, '/');
1384 self.status = CharClassesStatus::Normal;
1385 return Some((FullCodeCharKind::EndComment, item));
1387 self.status = CharClassesStatus::BlockComment(deepness);
1388 return Some((FullCodeCharKind::InComment, item));
1391 CharClassesStatus::LineComment => match chr {
1393 self.status = CharClassesStatus::Normal;
1394 return Some((FullCodeCharKind::EndComment, item));
1397 self.status = CharClassesStatus::LineComment;
1398 return Some((FullCodeCharKind::InComment, item));
1402 Some((char_kind, item))
1406 /// An iterator over the lines of a string, paired with the char kind at the
1407 /// end of the line.
1408 pub(crate) struct LineClasses<'a> {
1409 base: iter::Peekable<CharClasses<std::str::Chars<'a>>>,
1410 kind: FullCodeCharKind,
1413 impl<'a> LineClasses<'a> {
1414 pub(crate) fn new(s: &'a str) -> Self {
1416 base: CharClasses::new(s.chars()).peekable(),
1417 kind: FullCodeCharKind::Normal,
1422 impl<'a> Iterator for LineClasses<'a> {
1423 type Item = (FullCodeCharKind, String);
1425 fn next(&mut self) -> Option<Self::Item> {
1428 let mut line = String::new();
1430 let start_kind = match self.base.peek() {
1431 Some((kind, _)) => *kind,
1432 None => unreachable!(),
1435 for (kind, c) in self.base.by_ref() {
1436 // needed to set the kind of the ending character on the last line
1439 self.kind = match (start_kind, kind) {
1440 (FullCodeCharKind::Normal, FullCodeCharKind::InString) => {
1441 FullCodeCharKind::StartString
1443 (FullCodeCharKind::InString, FullCodeCharKind::Normal) => {
1444 FullCodeCharKind::EndString
1446 (FullCodeCharKind::InComment, FullCodeCharKind::InStringCommented) => {
1447 FullCodeCharKind::StartStringCommented
1449 (FullCodeCharKind::InStringCommented, FullCodeCharKind::InComment) => {
1450 FullCodeCharKind::EndStringCommented
1459 // Workaround for CRLF newline.
1460 if line.ends_with('\r') {
1464 Some((self.kind, line))
1468 /// Iterator over functional and commented parts of a string. Any part of a string is either
1469 /// functional code, either *one* block comment, either *one* line comment. Whitespace between
1470 /// comments is functional code. Line comments contain their ending newlines.
1471 struct UngroupedCommentCodeSlices<'a> {
1473 iter: iter::Peekable<CharClasses<std::str::CharIndices<'a>>>,
1476 impl<'a> UngroupedCommentCodeSlices<'a> {
1477 fn new(code: &'a str) -> UngroupedCommentCodeSlices<'a> {
1478 UngroupedCommentCodeSlices {
1480 iter: CharClasses::new(code.char_indices()).peekable(),
1485 impl<'a> Iterator for UngroupedCommentCodeSlices<'a> {
1486 type Item = (CodeCharKind, usize, &'a str);
1488 fn next(&mut self) -> Option<Self::Item> {
1489 let (kind, (start_idx, _)) = self.iter.next()?;
1491 FullCodeCharKind::Normal | FullCodeCharKind::InString => {
1492 // Consume all the Normal code
1493 while let Some(&(char_kind, _)) = self.iter.peek() {
1494 if char_kind.is_comment() {
1497 let _ = self.iter.next();
1500 FullCodeCharKind::StartComment => {
1501 // Consume the whole comment
1503 match self.iter.next() {
1504 Some((kind, ..)) if kind.inside_comment() => continue,
1511 let slice = match self.iter.peek() {
1512 Some(&(_, (end_idx, _))) => &self.slice[start_idx..end_idx],
1513 None => &self.slice[start_idx..],
1516 if kind.is_comment() {
1517 CodeCharKind::Comment
1519 CodeCharKind::Normal
1527 /// Iterator over an alternating sequence of functional and commented parts of
1528 /// a string. The first item is always a, possibly zero length, subslice of
1529 /// functional text. Line style comments contain their ending newlines.
1530 pub(crate) struct CommentCodeSlices<'a> {
1532 last_slice_kind: CodeCharKind,
1533 last_slice_end: usize,
1536 impl<'a> CommentCodeSlices<'a> {
1537 pub(crate) fn new(slice: &'a str) -> CommentCodeSlices<'a> {
1540 last_slice_kind: CodeCharKind::Comment,
1546 impl<'a> Iterator for CommentCodeSlices<'a> {
1547 type Item = (CodeCharKind, usize, &'a str);
1549 fn next(&mut self) -> Option<Self::Item> {
1550 if self.last_slice_end == self.slice.len() {
1554 let mut sub_slice_end = self.last_slice_end;
1555 let mut first_whitespace = None;
1556 let subslice = &self.slice[self.last_slice_end..];
1557 let mut iter = CharClasses::new(subslice.char_indices());
1559 for (kind, (i, c)) in &mut iter {
1560 let is_comment_connector = self.last_slice_kind == CodeCharKind::Normal
1561 && &subslice[..2] == "//"
1562 && [' ', '\t'].contains(&c);
1564 if is_comment_connector && first_whitespace.is_none() {
1565 first_whitespace = Some(i);
1568 if kind.to_codecharkind() == self.last_slice_kind && !is_comment_connector {
1569 let last_index = match first_whitespace {
1573 sub_slice_end = self.last_slice_end + last_index;
1577 if !is_comment_connector {
1578 first_whitespace = None;
1582 if let (None, true) = (iter.next(), sub_slice_end == self.last_slice_end) {
1583 // This was the last subslice.
1584 sub_slice_end = match first_whitespace {
1585 Some(i) => self.last_slice_end + i,
1586 None => self.slice.len(),
1590 let kind = match self.last_slice_kind {
1591 CodeCharKind::Comment => CodeCharKind::Normal,
1592 CodeCharKind::Normal => CodeCharKind::Comment,
1596 self.last_slice_end,
1597 &self.slice[self.last_slice_end..sub_slice_end],
1599 self.last_slice_end = sub_slice_end;
1600 self.last_slice_kind = kind;
1606 /// Checks is `new` didn't miss any comment from `span`, if it removed any, return previous text
1607 /// (if it fits in the width/offset, else return `None`), else return `new`
1608 pub(crate) fn recover_comment_removed(
1611 context: &RewriteContext<'_>,
1612 ) -> Option<String> {
1613 let snippet = context.snippet(span);
1614 if snippet != new && changed_comment_content(snippet, &new) {
1615 // We missed some comments. Warn and keep the original text.
1616 if context.config.error_on_unformatted() {
1617 context.report.append(
1618 context.parse_sess.span_to_filename(span),
1619 vec![FormattingError::from_span(
1622 ErrorKind::LostComment,
1626 Some(snippet.to_owned())
1632 pub(crate) fn filter_normal_code(code: &str) -> String {
1633 let mut buffer = String::with_capacity(code.len());
1634 LineClasses::new(code).for_each(|(kind, line)| match kind {
1635 FullCodeCharKind::Normal
1636 | FullCodeCharKind::StartString
1637 | FullCodeCharKind::InString
1638 | FullCodeCharKind::EndString => {
1639 buffer.push_str(&line);
1644 if !code.ends_with('\n') && buffer.ends_with('\n') {
1650 /// Returns `true` if the two strings of code have the same payload of comments.
1651 /// The payload of comments is everything in the string except:
1652 /// - actual code (not comments),
1653 /// - comment start/end marks,
1655 /// - '*' at the beginning of lines in block comments.
1656 fn changed_comment_content(orig: &str, new: &str) -> bool {
1657 // Cannot write this as a fn since we cannot return types containing closures.
1658 let code_comment_content = |code| {
1659 let slices = UngroupedCommentCodeSlices::new(code);
1661 .filter(|&(ref kind, _, _)| *kind == CodeCharKind::Comment)
1662 .flat_map(|(_, _, s)| CommentReducer::new(s))
1664 let res = code_comment_content(orig).ne(code_comment_content(new));
1666 "comment::changed_comment_content: {}\norig: '{}'\nnew: '{}'\nraw_old: {}\nraw_new: {}",
1670 code_comment_content(orig).collect::<String>(),
1671 code_comment_content(new).collect::<String>()
1676 /// Iterator over the 'payload' characters of a comment.
1677 /// It skips whitespace, comment start/end marks, and '*' at the beginning of lines.
1678 /// The comment must be one comment, ie not more than one start mark (no multiple line comments,
1680 struct CommentReducer<'a> {
1682 at_start_line: bool,
1683 iter: std::str::Chars<'a>,
1686 impl<'a> CommentReducer<'a> {
1687 fn new(comment: &'a str) -> CommentReducer<'a> {
1688 let is_block = comment.starts_with("/*");
1689 let comment = remove_comment_header(comment);
1692 // There are no supplementary '*' on the first line.
1693 at_start_line: false,
1694 iter: comment.chars(),
1699 impl<'a> Iterator for CommentReducer<'a> {
1702 fn next(&mut self) -> Option<Self::Item> {
1704 let mut c = self.iter.next()?;
1705 if self.is_block && self.at_start_line {
1706 while c.is_whitespace() {
1707 c = self.iter.next()?;
1709 // Ignore leading '*'.
1711 c = self.iter.next()?;
1713 } else if c == '\n' {
1714 self.at_start_line = true;
1716 if !c.is_whitespace() {
1723 fn remove_comment_header(comment: &str) -> &str {
1724 if comment.starts_with("///") || comment.starts_with("//!") {
1726 } else if let Some(stripped) = comment.strip_prefix("//") {
1728 } else if (comment.starts_with("/**") && !comment.starts_with("/**/"))
1729 || comment.starts_with("/*!")
1731 &comment[3..comment.len() - 2]
1734 comment.starts_with("/*"),
1735 "string '{}' is not a comment",
1738 &comment[2..comment.len() - 2]
1745 use crate::shape::{Indent, Shape};
1749 let mut iter = CharClasses::new("//\n\n".chars());
1751 assert_eq!((FullCodeCharKind::StartComment, '/'), iter.next().unwrap());
1752 assert_eq!((FullCodeCharKind::InComment, '/'), iter.next().unwrap());
1753 assert_eq!((FullCodeCharKind::EndComment, '\n'), iter.next().unwrap());
1754 assert_eq!((FullCodeCharKind::Normal, '\n'), iter.next().unwrap());
1755 assert_eq!(None, iter.next());
1759 fn comment_code_slices() {
1760 let input = "code(); /* test */ 1 + 1";
1761 let mut iter = CommentCodeSlices::new(input);
1763 assert_eq!((CodeCharKind::Normal, 0, "code(); "), iter.next().unwrap());
1765 (CodeCharKind::Comment, 8, "/* test */"),
1766 iter.next().unwrap()
1768 assert_eq!((CodeCharKind::Normal, 18, " 1 + 1"), iter.next().unwrap());
1769 assert_eq!(None, iter.next());
1773 fn comment_code_slices_two() {
1774 let input = "// comment\n test();";
1775 let mut iter = CommentCodeSlices::new(input);
1777 assert_eq!((CodeCharKind::Normal, 0, ""), iter.next().unwrap());
1779 (CodeCharKind::Comment, 0, "// comment\n"),
1780 iter.next().unwrap()
1783 (CodeCharKind::Normal, 11, " test();"),
1784 iter.next().unwrap()
1786 assert_eq!(None, iter.next());
1790 fn comment_code_slices_three() {
1791 let input = "1 // comment\n // comment2\n\n";
1792 let mut iter = CommentCodeSlices::new(input);
1794 assert_eq!((CodeCharKind::Normal, 0, "1 "), iter.next().unwrap());
1796 (CodeCharKind::Comment, 2, "// comment\n // comment2\n"),
1797 iter.next().unwrap()
1799 assert_eq!((CodeCharKind::Normal, 29, "\n"), iter.next().unwrap());
1800 assert_eq!(None, iter.next());
1805 fn format_doc_comments() {
1806 let mut wrap_normalize_config: crate::config::Config = Default::default();
1807 wrap_normalize_config.set().wrap_comments(true);
1808 wrap_normalize_config.set().normalize_comments(true);
1810 let mut wrap_config: crate::config::Config = Default::default();
1811 wrap_config.set().wrap_comments(true);
1813 let comment = rewrite_comment(" //test",
1815 Shape::legacy(100, Indent::new(0, 100)),
1816 &wrap_normalize_config).unwrap();
1817 assert_eq!("/* test */", comment);
1819 let comment = rewrite_comment("// comment on a",
1821 Shape::legacy(10, Indent::empty()),
1822 &wrap_normalize_config).unwrap();
1823 assert_eq!("// comment\n// on a", comment);
1825 let comment = rewrite_comment("// A multi line comment\n // between args.",
1827 Shape::legacy(60, Indent::new(0, 12)),
1828 &wrap_normalize_config).unwrap();
1829 assert_eq!("// A multi line comment\n // between args.", comment);
1831 let input = "// comment";
1834 let comment = rewrite_comment(input,
1836 Shape::legacy(9, Indent::new(0, 69)),
1837 &wrap_normalize_config).unwrap();
1838 assert_eq!(expected, comment);
1840 let comment = rewrite_comment("/* trimmed */",
1842 Shape::legacy(100, Indent::new(0, 100)),
1843 &wrap_normalize_config).unwrap();
1844 assert_eq!("/* trimmed */", comment);
1846 // Check that different comment style are properly recognised.
1847 let comment = rewrite_comment(r#"/// test1
1853 Shape::legacy(100, Indent::new(0, 0)),
1854 &wrap_normalize_config).unwrap();
1855 assert_eq!("/// test1\n/// test2\n// test3", comment);
1857 // Check that the blank line marks the end of a commented paragraph.
1858 let comment = rewrite_comment(r#"// test1
1862 Shape::legacy(100, Indent::new(0, 0)),
1863 &wrap_normalize_config).unwrap();
1864 assert_eq!("// test1\n\n// test2", comment);
1866 // Check that the blank line marks the end of a custom-commented paragraph.
1867 let comment = rewrite_comment(r#"//@ test1
1871 Shape::legacy(100, Indent::new(0, 0)),
1872 &wrap_normalize_config).unwrap();
1873 assert_eq!("//@ test1\n\n//@ test2", comment);
1875 // Check that bare lines are just indented but otherwise left unchanged.
1876 let comment = rewrite_comment(r#"// test1
1883 Shape::legacy(100, Indent::new(0, 0)),
1884 &wrap_config).unwrap();
1885 assert_eq!("// test1\n/*\n a bare line!\n\n another bare line!\n*/", comment);
1888 // This is probably intended to be a non-test fn, but it is not used.
1889 // We should keep this around unless it helps us test stuff to remove it.
1890 fn uncommented(text: &str) -> String {
1891 CharClasses::new(text.chars())
1892 .filter_map(|(s, c)| match s {
1893 FullCodeCharKind::Normal | FullCodeCharKind::InString => Some(c),
1900 fn test_uncommented() {
1901 assert_eq!(&uncommented("abc/*...*/"), "abc");
1903 &uncommented("// .... /* \n../* /* *** / */ */a/* // */c\n"),
1906 assert_eq!(&uncommented("abc \" /* */\" qsdf"), "abc \" /* */\" qsdf");
1910 fn test_contains_comment() {
1911 assert_eq!(contains_comment("abc"), false);
1912 assert_eq!(contains_comment("abc // qsdf"), true);
1913 assert_eq!(contains_comment("abc /* kqsdf"), true);
1914 assert_eq!(contains_comment("abc \" /* */\" qsdf"), false);
1918 fn test_find_uncommented() {
1919 fn check(haystack: &str, needle: &str, expected: Option<usize>) {
1920 assert_eq!(expected, haystack.find_uncommented(needle));
1923 check("/*/ */test", "test", Some(6));
1924 check("//test\ntest", "test", Some(7));
1925 check("/* comment only */", "whatever", None);
1927 "/* comment */ some text /* more commentary */ result",
1931 check("sup // sup", "p", Some(2));
1932 check("sup", "x", None);
1933 check(r#"π? /**/ π is nice!"#, r#"π is nice"#, Some(9));
1934 check("/*sup yo? \n sup*/ sup", "p", Some(20));
1935 check("hel/*lohello*/lo", "hello", None);
1936 check("acb", "ab", None);
1937 check(",/*A*/ ", ",", Some(0));
1938 check("abc", "abc", Some(0));
1939 check("/* abc */", "abc", None);
1940 check("/**/abc/* */", "abc", Some(4));
1941 check("\"/* abc */\"", "abc", Some(4));
1942 check("\"/* abc", "abc", Some(4));
1946 fn test_filter_normal_code() {
1949 println!("hello, world");
1952 assert_eq!(s, filter_normal_code(s));
1953 let s_with_comment = r#"
1956 println!("hello, world");
1959 assert_eq!(s, filter_normal_code(s_with_comment));