summaryrefslogtreecommitdiffstats
path: root/src/tools/rustfmt/src/formatting.rs
diff options
context:
space:
mode:
Diffstat (limited to 'src/tools/rustfmt/src/formatting.rs')
-rw-r--r--src/tools/rustfmt/src/formatting.rs632
1 files changed, 632 insertions, 0 deletions
diff --git a/src/tools/rustfmt/src/formatting.rs b/src/tools/rustfmt/src/formatting.rs
new file mode 100644
index 000000000..1dfd8a514
--- /dev/null
+++ b/src/tools/rustfmt/src/formatting.rs
@@ -0,0 +1,632 @@
+// High level formatting functions.
+
+use std::collections::HashMap;
+use std::io::{self, Write};
+use std::time::{Duration, Instant};
+
+use rustc_ast::ast;
+use rustc_span::Span;
+
+use self::newline_style::apply_newline_style;
+use crate::comment::{CharClasses, FullCodeCharKind};
+use crate::config::{Config, FileName, Verbosity};
+use crate::formatting::generated::is_generated_file;
+use crate::modules::Module;
+use crate::parse::parser::{DirectoryOwnership, Parser, ParserError};
+use crate::parse::session::ParseSess;
+use crate::utils::{contains_skip, count_newlines};
+use crate::visitor::FmtVisitor;
+use crate::{modules, source_file, ErrorKind, FormatReport, Input, Session};
+
+mod generated;
+mod newline_style;
+
+// A map of the files of a crate, with their new content
+pub(crate) type SourceFile = Vec<FileRecord>;
+pub(crate) type FileRecord = (FileName, String);
+
+impl<'b, T: Write + 'b> Session<'b, T> {
+ pub(crate) fn format_input_inner(
+ &mut self,
+ input: Input,
+ is_macro_def: bool,
+ ) -> Result<FormatReport, ErrorKind> {
+ if !self.config.version_meets_requirement() {
+ return Err(ErrorKind::VersionMismatch);
+ }
+
+ rustc_span::create_session_if_not_set_then(self.config.edition().into(), |_| {
+ if self.config.disable_all_formatting() {
+ // When the input is from stdin, echo back the input.
+ return match input {
+ Input::Text(ref buf) => echo_back_stdin(buf),
+ _ => Ok(FormatReport::new()),
+ };
+ }
+
+ let config = &self.config.clone();
+ let format_result = format_project(input, config, self, is_macro_def);
+
+ format_result.map(|report| {
+ self.errors.add(&report.internal.borrow().1);
+ report
+ })
+ })
+ }
+}
+
+/// Determine if a module should be skipped. True if the module should be skipped, false otherwise.
+fn should_skip_module<T: FormatHandler>(
+ config: &Config,
+ context: &FormatContext<'_, T>,
+ input_is_stdin: bool,
+ main_file: &FileName,
+ path: &FileName,
+ module: &Module<'_>,
+) -> bool {
+ if contains_skip(module.attrs()) {
+ return true;
+ }
+
+ if config.skip_children() && path != main_file {
+ return true;
+ }
+
+ if !input_is_stdin && context.ignore_file(path) {
+ return true;
+ }
+
+ // FIXME(calebcartwright) - we need to determine how we'll handle the
+ // `format_generated_files` option with stdin based input.
+ if !input_is_stdin && !config.format_generated_files() {
+ let source_file = context.parse_session.span_to_file_contents(module.span);
+ let src = source_file.src.as_ref().expect("SourceFile without src");
+
+ if is_generated_file(src) {
+ return true;
+ }
+ }
+
+ false
+}
+
+fn echo_back_stdin(input: &str) -> Result<FormatReport, ErrorKind> {
+ if let Err(e) = io::stdout().write_all(input.as_bytes()) {
+ return Err(From::from(e));
+ }
+ Ok(FormatReport::new())
+}
+
+// Format an entire crate (or subset of the module tree).
+fn format_project<T: FormatHandler>(
+ input: Input,
+ config: &Config,
+ handler: &mut T,
+ is_macro_def: bool,
+) -> Result<FormatReport, ErrorKind> {
+ let mut timer = Timer::start();
+
+ let main_file = input.file_name();
+ let input_is_stdin = main_file == FileName::Stdin;
+
+ let parse_session = ParseSess::new(config)?;
+ if config.skip_children() && parse_session.ignore_file(&main_file) {
+ return Ok(FormatReport::new());
+ }
+
+ // Parse the crate.
+ let mut report = FormatReport::new();
+ let directory_ownership = input.to_directory_ownership();
+ let krate = match Parser::parse_crate(input, &parse_session) {
+ Ok(krate) => krate,
+ // Surface parse error via Session (errors are merged there from report)
+ Err(e) => {
+ let forbid_verbose = input_is_stdin || e != ParserError::ParsePanicError;
+ should_emit_verbose(forbid_verbose, config, || {
+ eprintln!("The Rust parser panicked");
+ });
+ report.add_parsing_error();
+ return Ok(report);
+ }
+ };
+
+ let mut context = FormatContext::new(&krate, report, parse_session, config, handler);
+ let files = modules::ModResolver::new(
+ &context.parse_session,
+ directory_ownership.unwrap_or(DirectoryOwnership::UnownedViaBlock),
+ !input_is_stdin && !config.skip_children(),
+ )
+ .visit_crate(&krate)?
+ .into_iter()
+ .filter(|(path, module)| {
+ input_is_stdin
+ || !should_skip_module(config, &context, input_is_stdin, &main_file, path, module)
+ })
+ .collect::<Vec<_>>();
+
+ timer = timer.done_parsing();
+
+ // Suppress error output if we have to do any further parsing.
+ context.parse_session.set_silent_emitter();
+
+ for (path, module) in files {
+ if input_is_stdin && contains_skip(module.attrs()) {
+ return echo_back_stdin(
+ context
+ .parse_session
+ .snippet_provider(module.span)
+ .entire_snippet(),
+ );
+ }
+ should_emit_verbose(input_is_stdin, config, || println!("Formatting {}", path));
+ context.format_file(path, &module, is_macro_def)?;
+ }
+ timer = timer.done_formatting();
+
+ should_emit_verbose(input_is_stdin, config, || {
+ println!(
+ "Spent {0:.3} secs in the parsing phase, and {1:.3} secs in the formatting phase",
+ timer.get_parse_time(),
+ timer.get_format_time(),
+ )
+ });
+
+ Ok(context.report)
+}
+
+// Used for formatting files.
+#[derive(new)]
+struct FormatContext<'a, T: FormatHandler> {
+ krate: &'a ast::Crate,
+ report: FormatReport,
+ parse_session: ParseSess,
+ config: &'a Config,
+ handler: &'a mut T,
+}
+
+impl<'a, T: FormatHandler + 'a> FormatContext<'a, T> {
+ fn ignore_file(&self, path: &FileName) -> bool {
+ self.parse_session.ignore_file(path)
+ }
+
+ // Formats a single file/module.
+ fn format_file(
+ &mut self,
+ path: FileName,
+ module: &Module<'_>,
+ is_macro_def: bool,
+ ) -> Result<(), ErrorKind> {
+ let snippet_provider = self.parse_session.snippet_provider(module.span);
+ let mut visitor = FmtVisitor::from_parse_sess(
+ &self.parse_session,
+ self.config,
+ &snippet_provider,
+ self.report.clone(),
+ );
+ visitor.skip_context.update_with_attrs(&self.krate.attrs);
+ visitor.is_macro_def = is_macro_def;
+ visitor.last_pos = snippet_provider.start_pos();
+ visitor.skip_empty_lines(snippet_provider.end_pos());
+ visitor.format_separate_mod(module, snippet_provider.end_pos());
+
+ debug_assert_eq!(
+ visitor.line_number,
+ count_newlines(&visitor.buffer),
+ "failed in format_file visitor.buffer:\n {:?}",
+ &visitor.buffer
+ );
+
+ // For some reason, the source_map does not include terminating
+ // newlines so we must add one on for each file. This is sad.
+ source_file::append_newline(&mut visitor.buffer);
+
+ format_lines(
+ &mut visitor.buffer,
+ &path,
+ &visitor.skipped_range.borrow(),
+ self.config,
+ &self.report,
+ );
+
+ apply_newline_style(
+ self.config.newline_style(),
+ &mut visitor.buffer,
+ snippet_provider.entire_snippet(),
+ );
+
+ if visitor.macro_rewrite_failure {
+ self.report.add_macro_format_failure();
+ }
+ self.report
+ .add_non_formatted_ranges(visitor.skipped_range.borrow().clone());
+
+ self.handler.handle_formatted_file(
+ &self.parse_session,
+ path,
+ visitor.buffer.to_owned(),
+ &mut self.report,
+ )
+ }
+}
+
+// Handle the results of formatting.
+trait FormatHandler {
+ fn handle_formatted_file(
+ &mut self,
+ parse_session: &ParseSess,
+ path: FileName,
+ result: String,
+ report: &mut FormatReport,
+ ) -> Result<(), ErrorKind>;
+}
+
+impl<'b, T: Write + 'b> FormatHandler for Session<'b, T> {
+ // Called for each formatted file.
+ fn handle_formatted_file(
+ &mut self,
+ parse_session: &ParseSess,
+ path: FileName,
+ result: String,
+ report: &mut FormatReport,
+ ) -> Result<(), ErrorKind> {
+ if let Some(ref mut out) = self.out {
+ match source_file::write_file(
+ Some(parse_session),
+ &path,
+ &result,
+ out,
+ &mut *self.emitter,
+ self.config.newline_style(),
+ ) {
+ Ok(ref result) if result.has_diff => report.add_diff(),
+ Err(e) => {
+ // Create a new error with path_str to help users see which files failed
+ let err_msg = format!("{}: {}", path, e);
+ return Err(io::Error::new(e.kind(), err_msg).into());
+ }
+ _ => {}
+ }
+ }
+
+ self.source_file.push((path, result));
+ Ok(())
+ }
+}
+
+pub(crate) struct FormattingError {
+ pub(crate) line: usize,
+ pub(crate) kind: ErrorKind,
+ is_comment: bool,
+ is_string: bool,
+ pub(crate) line_buffer: String,
+}
+
+impl FormattingError {
+ pub(crate) fn from_span(
+ span: Span,
+ parse_sess: &ParseSess,
+ kind: ErrorKind,
+ ) -> FormattingError {
+ FormattingError {
+ line: parse_sess.line_of_byte_pos(span.lo()),
+ is_comment: kind.is_comment(),
+ kind,
+ is_string: false,
+ line_buffer: parse_sess.span_to_first_line_string(span),
+ }
+ }
+
+ pub(crate) fn is_internal(&self) -> bool {
+ match self.kind {
+ ErrorKind::LineOverflow(..)
+ | ErrorKind::TrailingWhitespace
+ | ErrorKind::IoError(_)
+ | ErrorKind::ParseError
+ | ErrorKind::LostComment => true,
+ _ => false,
+ }
+ }
+
+ pub(crate) fn msg_suffix(&self) -> &str {
+ if self.is_comment || self.is_string {
+ "set `error_on_unformatted = false` to suppress \
+ the warning against comments or string literals\n"
+ } else {
+ ""
+ }
+ }
+
+ // (space, target)
+ pub(crate) fn format_len(&self) -> (usize, usize) {
+ match self.kind {
+ ErrorKind::LineOverflow(found, max) => (max, found - max),
+ ErrorKind::TrailingWhitespace
+ | ErrorKind::DeprecatedAttr
+ | ErrorKind::BadAttr
+ | ErrorKind::LostComment => {
+ let trailing_ws_start = self
+ .line_buffer
+ .rfind(|c: char| !c.is_whitespace())
+ .map(|pos| pos + 1)
+ .unwrap_or(0);
+ (
+ trailing_ws_start,
+ self.line_buffer.len() - trailing_ws_start,
+ )
+ }
+ _ => unreachable!(),
+ }
+ }
+}
+
+pub(crate) type FormatErrorMap = HashMap<FileName, Vec<FormattingError>>;
+
+#[derive(Default, Debug, PartialEq)]
+pub(crate) struct ReportedErrors {
+ // Encountered e.g., an IO error.
+ pub(crate) has_operational_errors: bool,
+
+ // Failed to reformat code because of parsing errors.
+ pub(crate) has_parsing_errors: bool,
+
+ // Code is valid, but it is impossible to format it properly.
+ pub(crate) has_formatting_errors: bool,
+
+ // Code contains macro call that was unable to format.
+ pub(crate) has_macro_format_failure: bool,
+
+ // Failed an opt-in checking.
+ pub(crate) has_check_errors: bool,
+
+ /// Formatted code differs from existing code (--check only).
+ pub(crate) has_diff: bool,
+
+ /// Formatted code missed something, like lost comments or extra trailing space
+ pub(crate) has_unformatted_code_errors: bool,
+}
+
+impl ReportedErrors {
+ /// Combine two summaries together.
+ pub(crate) fn add(&mut self, other: &ReportedErrors) {
+ self.has_operational_errors |= other.has_operational_errors;
+ self.has_parsing_errors |= other.has_parsing_errors;
+ self.has_formatting_errors |= other.has_formatting_errors;
+ self.has_macro_format_failure |= other.has_macro_format_failure;
+ self.has_check_errors |= other.has_check_errors;
+ self.has_diff |= other.has_diff;
+ self.has_unformatted_code_errors |= other.has_unformatted_code_errors;
+ }
+}
+
+#[derive(Clone, Copy, Debug)]
+enum Timer {
+ Disabled,
+ Initialized(Instant),
+ DoneParsing(Instant, Instant),
+ DoneFormatting(Instant, Instant, Instant),
+}
+
+impl Timer {
+ fn start() -> Timer {
+ if cfg!(target_arch = "wasm32") {
+ Timer::Disabled
+ } else {
+ Timer::Initialized(Instant::now())
+ }
+ }
+ fn done_parsing(self) -> Self {
+ match self {
+ Timer::Disabled => Timer::Disabled,
+ Timer::Initialized(init_time) => Timer::DoneParsing(init_time, Instant::now()),
+ _ => panic!("Timer can only transition to DoneParsing from Initialized state"),
+ }
+ }
+
+ fn done_formatting(self) -> Self {
+ match self {
+ Timer::Disabled => Timer::Disabled,
+ Timer::DoneParsing(init_time, parse_time) => {
+ Timer::DoneFormatting(init_time, parse_time, Instant::now())
+ }
+ _ => panic!("Timer can only transition to DoneFormatting from DoneParsing state"),
+ }
+ }
+
+ /// Returns the time it took to parse the source files in seconds.
+ fn get_parse_time(&self) -> f32 {
+ match *self {
+ Timer::Disabled => panic!("this platform cannot time execution"),
+ Timer::DoneParsing(init, parse_time) | Timer::DoneFormatting(init, parse_time, _) => {
+ // This should never underflow since `Instant::now()` guarantees monotonicity.
+ Self::duration_to_f32(parse_time.duration_since(init))
+ }
+ Timer::Initialized(..) => unreachable!(),
+ }
+ }
+
+ /// Returns the time it took to go from the parsed AST to the formatted output. Parsing time is
+ /// not included.
+ fn get_format_time(&self) -> f32 {
+ match *self {
+ Timer::Disabled => panic!("this platform cannot time execution"),
+ Timer::DoneFormatting(_init, parse_time, format_time) => {
+ Self::duration_to_f32(format_time.duration_since(parse_time))
+ }
+ Timer::DoneParsing(..) | Timer::Initialized(..) => unreachable!(),
+ }
+ }
+
+ fn duration_to_f32(d: Duration) -> f32 {
+ d.as_secs() as f32 + d.subsec_nanos() as f32 / 1_000_000_000f32
+ }
+}
+
+// Formatting done on a char by char or line by line basis.
+// FIXME(#20): other stuff for parity with make tidy.
+fn format_lines(
+ text: &mut String,
+ name: &FileName,
+ skipped_range: &[(usize, usize)],
+ config: &Config,
+ report: &FormatReport,
+) {
+ let mut formatter = FormatLines::new(name, skipped_range, config);
+ formatter.iterate(text);
+
+ if formatter.newline_count > 1 {
+ debug!("track truncate: {} {}", text.len(), formatter.newline_count);
+ let line = text.len() - formatter.newline_count + 1;
+ text.truncate(line);
+ }
+
+ report.append(name.clone(), formatter.errors);
+}
+
+struct FormatLines<'a> {
+ name: &'a FileName,
+ skipped_range: &'a [(usize, usize)],
+ last_was_space: bool,
+ line_len: usize,
+ cur_line: usize,
+ newline_count: usize,
+ errors: Vec<FormattingError>,
+ line_buffer: String,
+ current_line_contains_string_literal: bool,
+ format_line: bool,
+ config: &'a Config,
+}
+
+impl<'a> FormatLines<'a> {
+ fn new(
+ name: &'a FileName,
+ skipped_range: &'a [(usize, usize)],
+ config: &'a Config,
+ ) -> FormatLines<'a> {
+ FormatLines {
+ name,
+ skipped_range,
+ last_was_space: false,
+ line_len: 0,
+ cur_line: 1,
+ newline_count: 0,
+ errors: vec![],
+ line_buffer: String::with_capacity(config.max_width() * 2),
+ current_line_contains_string_literal: false,
+ format_line: config.file_lines().contains_line(name, 1),
+ config,
+ }
+ }
+
+ // Iterate over the chars in the file map.
+ fn iterate(&mut self, text: &mut String) {
+ for (kind, c) in CharClasses::new(text.chars()) {
+ if c == '\r' {
+ continue;
+ }
+
+ if c == '\n' {
+ self.new_line(kind);
+ } else {
+ self.char(c, kind);
+ }
+ }
+ }
+
+ fn new_line(&mut self, kind: FullCodeCharKind) {
+ if self.format_line {
+ // Check for (and record) trailing whitespace.
+ if self.last_was_space {
+ if self.should_report_error(kind, &ErrorKind::TrailingWhitespace)
+ && !self.is_skipped_line()
+ {
+ self.push_err(
+ ErrorKind::TrailingWhitespace,
+ kind.is_comment(),
+ kind.is_string(),
+ );
+ }
+ self.line_len -= 1;
+ }
+
+ // Check for any line width errors we couldn't correct.
+ let error_kind = ErrorKind::LineOverflow(self.line_len, self.config.max_width());
+ if self.line_len > self.config.max_width()
+ && !self.is_skipped_line()
+ && self.should_report_error(kind, &error_kind)
+ {
+ let is_string = self.current_line_contains_string_literal;
+ self.push_err(error_kind, kind.is_comment(), is_string);
+ }
+ }
+
+ self.line_len = 0;
+ self.cur_line += 1;
+ self.format_line = self
+ .config
+ .file_lines()
+ .contains_line(self.name, self.cur_line);
+ self.newline_count += 1;
+ self.last_was_space = false;
+ self.line_buffer.clear();
+ self.current_line_contains_string_literal = false;
+ }
+
+ fn char(&mut self, c: char, kind: FullCodeCharKind) {
+ self.newline_count = 0;
+ self.line_len += if c == '\t' {
+ self.config.tab_spaces()
+ } else {
+ 1
+ };
+ self.last_was_space = c.is_whitespace();
+ self.line_buffer.push(c);
+ if kind.is_string() {
+ self.current_line_contains_string_literal = true;
+ }
+ }
+
+ fn push_err(&mut self, kind: ErrorKind, is_comment: bool, is_string: bool) {
+ self.errors.push(FormattingError {
+ line: self.cur_line,
+ kind,
+ is_comment,
+ is_string,
+ line_buffer: self.line_buffer.clone(),
+ });
+ }
+
+ fn should_report_error(&self, char_kind: FullCodeCharKind, error_kind: &ErrorKind) -> bool {
+ let allow_error_report = if char_kind.is_comment()
+ || self.current_line_contains_string_literal
+ || error_kind.is_comment()
+ {
+ self.config.error_on_unformatted()
+ } else {
+ true
+ };
+
+ match error_kind {
+ ErrorKind::LineOverflow(..) => {
+ self.config.error_on_line_overflow() && allow_error_report
+ }
+ ErrorKind::TrailingWhitespace | ErrorKind::LostComment => allow_error_report,
+ _ => true,
+ }
+ }
+
+ /// Returns `true` if the line with the given line number was skipped by `#[rustfmt::skip]`.
+ fn is_skipped_line(&self) -> bool {
+ self.skipped_range
+ .iter()
+ .any(|&(lo, hi)| lo <= self.cur_line && self.cur_line <= hi)
+ }
+}
+
+fn should_emit_verbose<F>(forbid_verbose_output: bool, config: &Config, f: F)
+where
+ F: Fn(),
+{
+ if config.verbose() == Verbosity::Verbose && !forbid_verbose_output {
+ f();
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-26 09:53:20 +0000