1 // Copyright 2015-2018 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.
12 extern crate derive_new;
14 extern crate bytecount;
18 extern crate itertools;
21 extern crate lazy_static;
25 extern crate rustc_target;
28 extern crate serde_derive;
29 extern crate serde_json;
31 extern crate syntax_pos;
33 extern crate unicode_categories;
34 extern crate unicode_segmentation;
35 extern crate unicode_width;
37 use std::cell::RefCell;
38 use std::collections::HashMap;
40 use std::io::{self, Write};
43 use std::path::PathBuf;
49 use crate::comment::LineClasses;
50 use crate::formatting::{FormatErrorMap, FormattingError, ReportedErrors, SourceFile};
51 use crate::issues::Issue;
52 use crate::shape::Indent;
54 pub use crate::config::{
55 load_config, CliOptions, Color, Config, Edition, EmitMode, FileLines, FileName, NewlineStyle,
64 pub(crate) mod checkstyle;
67 pub(crate) mod config;
69 pub(crate) mod formatting;
77 pub(crate) mod modules;
83 pub(crate) mod rustfmt_diff;
85 pub(crate) mod source_file;
86 pub(crate) mod source_map;
93 pub(crate) mod visitor;
95 /// The various errors that can occur during formatting. Note that not all of
96 /// these can currently be propagated to clients.
97 #[derive(Fail, Debug)]
99 /// Line has exceeded character limit (found, maximum).
101 display = "line formatted, but exceeded maximum width \
102 (maximum: {} (see `max_width` option), found: {})",
105 LineOverflow(usize, usize),
106 /// Line ends in whitespace.
107 #[fail(display = "left behind trailing whitespace")]
109 /// TODO or FIXME item without an issue number.
110 #[fail(display = "found {}", _0)]
112 /// License check has failed.
113 #[fail(display = "license check failed")]
115 /// Used deprecated skip attribute.
116 #[fail(display = "`rustfmt_skip` is deprecated; use `rustfmt::skip`")]
118 /// Used a rustfmt:: attribute other than skip.
119 #[fail(display = "invalid attribute")]
121 /// An io error during reading or writing.
122 #[fail(display = "io error: {}", _0)]
124 /// Parse error occurred when parsing the input.
125 #[fail(display = "parse error")]
127 /// The user mandated a version and the current version of Rustfmt does not
128 /// satisfy that requirement.
129 #[fail(display = "version mismatch")]
131 /// If we had formatted the given node, then we would have lost a comment.
132 #[fail(display = "not formatted because a comment would be lost")]
137 fn is_comment(&self) -> bool {
139 ErrorKind::LostComment => true,
145 impl From<io::Error> for ErrorKind {
146 fn from(e: io::Error) -> ErrorKind {
147 ErrorKind::IoError(e)
151 /// Result of formatting a snippet of code along with ranges of lines that didn't get formatted,
152 /// i.e., that got returned as they were originally.
154 struct FormattedSnippet {
156 non_formatted_ranges: Vec<(usize, usize)>,
159 impl FormattedSnippet {
160 /// In case the snippet needed to be wrapped in a function, this shifts down the ranges of
161 /// non-formatted code.
162 fn unwrap_code_block(&mut self) {
163 self.non_formatted_ranges
165 .for_each(|(low, high)| {
171 /// Returns true if the line n did not get formatted.
172 fn is_line_non_formatted(&self, n: usize) -> bool {
173 self.non_formatted_ranges
175 .any(|(low, high)| *low <= n && n <= *high)
179 /// Reports on any issues that occurred during a run of Rustfmt.
181 /// Can be reported to the user via its `Display` implementation of `print_fancy`.
183 pub struct FormatReport {
184 // Maps stringified file paths to their associated formatting errors.
185 internal: Rc<RefCell<(FormatErrorMap, ReportedErrors)>>,
186 non_formatted_ranges: Vec<(usize, usize)>,
190 fn new() -> FormatReport {
192 internal: Rc::new(RefCell::new((HashMap::new(), ReportedErrors::default()))),
193 non_formatted_ranges: Vec::new(),
197 fn add_non_formatted_ranges(&mut self, mut ranges: Vec<(usize, usize)>) {
198 self.non_formatted_ranges.append(&mut ranges);
201 fn append(&self, f: FileName, mut v: Vec<FormattingError>) {
202 self.track_errors(&v);
207 .and_modify(|fe| fe.append(&mut v))
211 fn track_errors(&self, new_errors: &[FormattingError]) {
212 let errs = &mut self.internal.borrow_mut().1;
213 if !new_errors.is_empty() {
214 errs.has_formatting_errors = true;
216 if errs.has_operational_errors && errs.has_check_errors {
219 for err in new_errors {
221 ErrorKind::LineOverflow(..) | ErrorKind::TrailingWhitespace => {
222 errs.has_operational_errors = true;
224 ErrorKind::BadIssue(_)
225 | ErrorKind::LicenseCheck
226 | ErrorKind::DeprecatedAttr
228 | ErrorKind::VersionMismatch => {
229 errs.has_check_errors = true;
236 fn add_diff(&mut self) {
237 self.internal.borrow_mut().1.has_diff = true;
240 fn add_macro_format_failure(&mut self) {
241 self.internal.borrow_mut().1.has_macro_format_failure = true;
244 fn add_parsing_error(&mut self) {
245 self.internal.borrow_mut().1.has_parsing_errors = true;
248 fn warning_count(&self) -> usize {
253 .map(|(_, errors)| errors.len())
257 /// Whether any warnings or errors are present in the report.
258 pub fn has_warnings(&self) -> bool {
259 self.internal.borrow().1.has_formatting_errors
262 /// Print the report to a terminal using colours and potentially other
266 mut t: Box<term::Terminal<Output = io::Stderr>>,
267 ) -> Result<(), term::Error> {
268 for (file, errors) in &self.internal.borrow().0 {
269 for error in errors {
270 let prefix_space_len = error.line.to_string().len();
271 let prefix_spaces = " ".repeat(1 + prefix_space_len);
273 // First line: the overview of error
274 t.fg(term::color::RED)?;
275 t.attr(term::Attr::Bold)?;
276 write!(t, "{} ", error.msg_prefix())?;
278 t.attr(term::Attr::Bold)?;
279 writeln!(t, "{}", error.kind)?;
281 // Second line: file info
282 write!(t, "{}--> ", &prefix_spaces[1..])?;
284 writeln!(t, "{}:{}", file, error.line)?;
286 // Third to fifth lines: show the line which triggered error, if available.
287 if !error.line_buffer.is_empty() {
288 let (space_len, target_len) = error.format_len();
289 t.attr(term::Attr::Bold)?;
290 write!(t, "{}|\n{} | ", prefix_spaces, error.line)?;
292 writeln!(t, "{}", error.line_buffer)?;
293 t.attr(term::Attr::Bold)?;
294 write!(t, "{}| ", prefix_spaces)?;
295 t.fg(term::color::RED)?;
296 writeln!(t, "{}", FormatReport::target_str(space_len, target_len))?;
300 // The last line: show note if available.
301 let msg_suffix = error.msg_suffix();
302 if !msg_suffix.is_empty() {
303 t.attr(term::Attr::Bold)?;
304 write!(t, "{}= note: ", prefix_spaces)?;
306 writeln!(t, "{}", error.msg_suffix())?;
314 if !self.internal.borrow().0.is_empty() {
315 t.attr(term::Attr::Bold)?;
316 write!(t, "warning: ")?;
320 "rustfmt may have failed to format. See previous {} errors.\n\n",
321 self.warning_count(),
328 fn target_str(space_len: usize, target_len: usize) -> String {
329 let empty_line = " ".repeat(space_len);
330 let overflowed = "^".repeat(target_len);
331 empty_line + &overflowed
335 impl fmt::Display for FormatReport {
336 // Prints all the formatting errors.
337 fn fmt(&self, fmt: &mut fmt::Formatter) -> Result<(), fmt::Error> {
338 for (file, errors) in &self.internal.borrow().0 {
339 for error in errors {
340 let prefix_space_len = error.line.to_string().len();
341 let prefix_spaces = " ".repeat(1 + prefix_space_len);
343 let error_line_buffer = if error.line_buffer.is_empty() {
346 let (space_len, target_len) = error.format_len();
348 "{}|\n{} | {}\n{}| {}",
353 FormatReport::target_str(space_len, target_len)
357 let error_info = format!("{} {}", error.msg_prefix(), error.kind);
358 let file_info = format!("{}--> {}:{}", &prefix_spaces[1..], file, error.line);
359 let msg_suffix = error.msg_suffix();
360 let note = if msg_suffix.is_empty() {
363 format!("{}note= ", prefix_spaces)
377 if !self.internal.borrow().0.is_empty() {
380 "warning: rustfmt may have failed to format. See previous {} errors.",
381 self.warning_count(),
388 /// Format the given snippet. The snippet is expected to be *complete* code.
389 /// When we cannot parse the given snippet, this function returns `None`.
390 fn format_snippet(snippet: &str, config: &Config) -> Option<FormattedSnippet> {
391 let mut config = config.clone();
392 panic::catch_unwind(|| {
393 let mut out: Vec<u8> = Vec::with_capacity(snippet.len() * 2);
394 config.set().emit_mode(config::EmitMode::Stdout);
395 config.set().verbose(Verbosity::Quiet);
396 config.set().hide_parse_errors(true);
398 let (formatting_error, result) = {
399 let input = Input::Text(snippet.into());
400 let mut session = Session::new(config, Some(&mut out));
401 let result = session.format(input);
403 session.errors.has_macro_format_failure
404 || session.out.as_ref().unwrap().is_empty() && !snippet.is_empty()
409 if formatting_error {
412 String::from_utf8(out).ok().map(|snippet| FormattedSnippet {
414 non_formatted_ranges: result.unwrap().non_formatted_ranges,
418 // Discard panics encountered while formatting the snippet
419 // The ? operator is needed to remove the extra Option
423 /// Format the given code block. Mainly targeted for code block in comment.
424 /// The code block may be incomplete (i.e. parser may be unable to parse it).
425 /// To avoid panic in parser, we wrap the code block with a dummy function.
426 /// The returned code block does *not* end with newline.
427 fn format_code_block(code_snippet: &str, config: &Config) -> Option<FormattedSnippet> {
428 const FN_MAIN_PREFIX: &str = "fn main() {\n";
430 fn enclose_in_main_block(s: &str, config: &Config) -> String {
431 let indent = Indent::from_width(config, config.tab_spaces());
432 let mut result = String::with_capacity(s.len() * 2);
433 result.push_str(FN_MAIN_PREFIX);
434 let mut need_indent = true;
435 for (kind, line) in LineClasses::new(s) {
437 result.push_str(&indent.to_string(config));
439 result.push_str(&line);
441 need_indent = !kind.is_string() || line.ends_with('\\');
447 // Wrap the given code block with `fn main()` if it does not have one.
448 let snippet = enclose_in_main_block(code_snippet, config);
449 let mut result = String::with_capacity(snippet.len());
450 let mut is_first = true;
452 // While formatting the code, ignore the config's newline style setting and always use "\n"
453 // instead of "\r\n" for the newline characters. This is okay because the output here is
454 // not directly outputted by rustfmt command, but used by the comment formatter's input.
455 // We have output-file-wide "\n" ==> "\r\n" conversion process after here if it's necessary.
456 let mut config_with_unix_newline = config.clone();
457 config_with_unix_newline
459 .newline_style(NewlineStyle::Unix);
460 let mut formatted = format_snippet(&snippet, &config_with_unix_newline)?;
461 // Remove wrapping main block
462 formatted.unwrap_code_block();
464 // Trim "fn main() {" on the first line and "}" on the last line,
465 // then unindent the whole code block.
466 let block_len = formatted
469 .unwrap_or(formatted.snippet.len());
470 let mut is_indented = true;
471 for (kind, ref line) in LineClasses::new(&formatted.snippet[FN_MAIN_PREFIX.len()..block_len]) {
477 let trimmed_line = if !is_indented {
479 } else if line.len() > config.max_width() {
480 // If there are lines that are larger than max width, we cannot tell
481 // whether we have succeeded but have some comments or strings that
482 // are too long, or we have failed to format code block. We will be
483 // conservative and just return `None` in this case.
485 } else if line.len() > config.tab_spaces() {
486 // Make sure that the line has leading whitespaces.
487 let indent_str = Indent::from_width(config, config.tab_spaces()).to_string(config);
488 if line.starts_with(indent_str.as_ref()) {
489 let offset = if config.hard_tabs() {
501 result.push_str(trimmed_line);
502 is_indented = !kind.is_string() || line.ends_with('\\');
504 Some(FormattedSnippet {
506 non_formatted_ranges: formatted.non_formatted_ranges,
510 /// A session is a run of rustfmt across a single or multiple inputs.
511 pub struct Session<'b, T: Write + 'b> {
513 pub out: Option<&'b mut T>,
514 pub(crate) errors: ReportedErrors,
515 source_file: SourceFile,
518 impl<'b, T: Write + 'b> Session<'b, T> {
519 pub fn new(config: Config, out: Option<&'b mut T>) -> Session<'b, T> {
520 if config.emit_mode() == EmitMode::Checkstyle {
521 println!("{}", checkstyle::header());
527 errors: ReportedErrors::default(),
528 source_file: SourceFile::new(),
532 /// The main entry point for Rustfmt. Formats the given input according to the
533 /// given config. `out` is only necessary if required by the configuration.
534 pub fn format(&mut self, input: Input) -> Result<FormatReport, ErrorKind> {
535 self.format_input_inner(input)
538 pub fn override_config<F, U>(&mut self, mut config: Config, f: F) -> U
540 F: FnOnce(&mut Session<'b, T>) -> U,
542 mem::swap(&mut config, &mut self.config);
543 let result = f(self);
544 mem::swap(&mut config, &mut self.config);
548 pub fn add_operational_error(&mut self) {
549 self.errors.has_operational_errors = true;
552 pub fn has_operational_errors(&self) -> bool {
553 self.errors.has_operational_errors
556 pub fn has_parsing_errors(&self) -> bool {
557 self.errors.has_parsing_errors
560 pub fn has_formatting_errors(&self) -> bool {
561 self.errors.has_formatting_errors
564 pub fn has_check_errors(&self) -> bool {
565 self.errors.has_check_errors
568 pub fn has_diff(&self) -> bool {
572 pub fn has_no_errors(&self) -> bool {
573 !(self.has_operational_errors()
574 || self.has_parsing_errors()
575 || self.has_formatting_errors()
576 || self.has_check_errors()
578 || self.errors.has_macro_format_failure
582 impl<'b, T: Write + 'b> Drop for Session<'b, T> {
584 if self.config.emit_mode() == EmitMode::Checkstyle {
585 println!("{}", checkstyle::footer());
597 fn is_text(&self) -> bool {
599 Input::File(_) => false,
600 Input::Text(_) => true,
604 fn file_name(&self) -> FileName {
606 Input::File(ref file) => FileName::Real(file.clone()),
607 Input::Text(..) => FileName::Stdin,
617 fn test_no_panic_on_format_snippet_and_format_code_block() {
618 // `format_snippet()` and `format_code_block()` should not panic
619 // even when we cannot parse the given snippet.
621 assert!(format_snippet(snippet, &Config::default()).is_none());
622 assert!(format_code_block(snippet, &Config::default()).is_none());
625 fn test_format_inner<F>(formatter: F, input: &str, expected: &str) -> bool
627 F: Fn(&str, &Config) -> Option<FormattedSnippet>,
629 let output = formatter(input, &Config::default());
630 output.is_some() && output.unwrap().snippet == expected
634 fn test_format_snippet() {
635 let snippet = "fn main() { println!(\"hello, world\"); }";
637 let expected = "fn main() {\n \
638 println!(\"hello, world\");\n\
641 let expected = "fn main() {\r\n \
642 println!(\"hello, world\");\r\n\
644 assert!(test_format_inner(format_snippet, snippet, expected));
648 fn test_format_code_block_fail() {
650 let code_block = "this_line_is_100_characters_long_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx(x, y, z);";
651 assert!(format_code_block(code_block, &Config::default()).is_none());
655 fn test_format_code_block() {
657 let code_block = "let x=3;";
658 let expected = "let x = 3;";
659 assert!(test_format_inner(format_code_block, code_block, expected));
661 // more complex code block, taken from chains.rs.
663 "let (nested_shape, extend) = if !parent_rewrite_contains_newline && is_continuable(&parent) {
665 chain_indent(context, shape.add_offset(parent_rewrite.len())),
666 context.config.indent_style() == IndentStyle::Visual || is_small_parent,
668 } else if is_block_expr(context, &parent, &parent_rewrite) {
669 match context.config.indent_style() {
670 // Try to put the first child on the same line with parent's last line
671 IndentStyle::Block => (parent_shape.block_indent(context.config.tab_spaces()), true),
672 // The parent is a block, so align the rest of the chain with the closing
674 IndentStyle::Visual => (parent_shape, false),
678 chain_indent(context, shape.add_offset(parent_rewrite.len())),
684 "let (nested_shape, extend) = if !parent_rewrite_contains_newline && is_continuable(&parent) {
686 chain_indent(context, shape.add_offset(parent_rewrite.len())),
687 context.config.indent_style() == IndentStyle::Visual || is_small_parent,
689 } else if is_block_expr(context, &parent, &parent_rewrite) {
690 match context.config.indent_style() {
691 // Try to put the first child on the same line with parent's last line
692 IndentStyle::Block => (parent_shape.block_indent(context.config.tab_spaces()), true),
693 // The parent is a block, so align the rest of the chain with the closing
695 IndentStyle::Visual => (parent_shape, false),
699 chain_indent(context, shape.add_offset(parent_rewrite.len())),
703 assert!(test_format_inner(format_code_block, code_block, expected));