4 self, Attribute, CrateSugar, MetaItem, MetaItemKind, NestedMetaItem, NodeId, Path, Visibility,
8 use rustc_ast_pretty::pprust;
9 use rustc_span::{sym, symbol, BytePos, ExpnId, Span, Symbol, SyntaxContext};
10 use unicode_width::UnicodeWidthStr;
12 use crate::comment::{filter_normal_code, CharClasses, FullCodeCharKind, LineClasses};
13 use crate::config::{Config, Version};
14 use crate::rewrite::RewriteContext;
15 use crate::shape::{Indent, Shape};
18 pub(crate) fn depr_skip_annotation() -> Symbol {
19 Symbol::intern("rustfmt_skip")
23 pub(crate) fn skip_annotation() -> Symbol {
24 Symbol::intern("rustfmt::skip")
27 pub(crate) fn rewrite_ident<'a>(context: &'a RewriteContext<'_>, ident: symbol::Ident) -> &'a str {
28 context.snippet(ident.span)
31 // Computes the length of a string's last line, minus offset.
32 pub(crate) fn extra_offset(text: &str, shape: Shape) -> usize {
33 match text.rfind('\n') {
34 // 1 for newline character
35 Some(idx) => text.len().saturating_sub(idx + 1 + shape.used_width()),
40 pub(crate) fn is_same_visibility(a: &Visibility, b: &Visibility) -> bool {
41 match (&a.node, &b.node) {
43 VisibilityKind::Restricted { path: p, .. },
44 VisibilityKind::Restricted { path: q, .. },
45 ) => pprust::path_to_string(p) == pprust::path_to_string(q),
46 (VisibilityKind::Public, VisibilityKind::Public)
47 | (VisibilityKind::Inherited, VisibilityKind::Inherited)
49 VisibilityKind::Crate(CrateSugar::PubCrate),
50 VisibilityKind::Crate(CrateSugar::PubCrate),
53 VisibilityKind::Crate(CrateSugar::JustCrate),
54 VisibilityKind::Crate(CrateSugar::JustCrate),
60 // Uses Cow to avoid allocating in the common cases.
61 pub(crate) fn format_visibility(
62 context: &RewriteContext<'_>,
64 ) -> Cow<'static, str> {
66 VisibilityKind::Public => Cow::from("pub "),
67 VisibilityKind::Inherited => Cow::from(""),
68 VisibilityKind::Crate(CrateSugar::PubCrate) => Cow::from("pub(crate) "),
69 VisibilityKind::Crate(CrateSugar::JustCrate) => Cow::from("crate "),
70 VisibilityKind::Restricted { ref path, .. } => {
71 let Path { ref segments, .. } = **path;
72 let mut segments_iter = segments.iter().map(|seg| rewrite_ident(context, seg.ident));
76 .expect("Non-global path in pub(restricted)?");
78 let is_keyword = |s: &str| s == "self" || s == "super";
79 let path = segments_iter.collect::<Vec<_>>().join("::");
80 let in_str = if is_keyword(&path) { "" } else { "in " };
82 Cow::from(format!("pub({}{}) ", in_str, path))
88 pub(crate) fn format_async(is_async: &ast::Async) -> &'static str {
90 ast::Async::Yes { .. } => "async ",
96 pub(crate) fn format_constness(constness: ast::Const) -> &'static str {
98 ast::Const::Yes(..) => "const ",
104 pub(crate) fn format_defaultness(defaultness: ast::Defaultness) -> &'static str {
106 ast::Defaultness::Default(..) => "default ",
107 ast::Defaultness::Final => "",
112 pub(crate) fn format_unsafety(unsafety: ast::Unsafe) -> &'static str {
114 ast::Unsafe::Yes(..) => "unsafe ",
115 ast::Unsafe::No => "",
120 pub(crate) fn format_auto(is_auto: ast::IsAuto) -> &'static str {
122 ast::IsAuto::Yes => "auto ",
123 ast::IsAuto::No => "",
128 pub(crate) fn format_mutability(mutability: ast::Mutability) -> &'static str {
130 ast::Mutability::Mut => "mut ",
131 ast::Mutability::Not => "",
136 pub(crate) fn format_extern(
140 ) -> Cow<'static, str> {
141 let abi = match ext {
142 ast::Extern::None => "Rust".to_owned(),
143 ast::Extern::Implicit => "C".to_owned(),
144 ast::Extern::Explicit(abi) => abi.symbol_unescaped.to_string(),
147 if abi == "Rust" && !is_mod {
149 } else if abi == "C" && !explicit_abi {
152 Cow::from(format!(r#"extern "{}" "#, abi))
157 // Transform `Vec<rustc_ast::ptr::P<T>>` into `Vec<&T>`
158 pub(crate) fn ptr_vec_to_ref_vec<T>(vec: &[ptr::P<T>]) -> Vec<&T> {
159 vec.iter().map(|x| &**x).collect::<Vec<_>>()
163 pub(crate) fn filter_attributes(
164 attrs: &[ast::Attribute],
165 style: ast::AttrStyle,
166 ) -> Vec<ast::Attribute> {
169 .filter(|a| a.style == style)
175 pub(crate) fn inner_attributes(attrs: &[ast::Attribute]) -> Vec<ast::Attribute> {
176 filter_attributes(attrs, ast::AttrStyle::Inner)
180 pub(crate) fn outer_attributes(attrs: &[ast::Attribute]) -> Vec<ast::Attribute> {
181 filter_attributes(attrs, ast::AttrStyle::Outer)
185 pub(crate) fn is_single_line(s: &str) -> bool {
186 s.chars().find(|&c| c == '\n').is_none()
190 pub(crate) fn first_line_contains_single_line_comment(s: &str) -> bool {
191 s.lines().next().map_or(false, |l| l.contains("//"))
195 pub(crate) fn last_line_contains_single_line_comment(s: &str) -> bool {
196 s.lines().last().map_or(false, |l| l.contains("//"))
200 pub(crate) fn is_attributes_extendable(attrs_str: &str) -> bool {
201 !attrs_str.contains('\n') && !last_line_contains_single_line_comment(attrs_str)
204 /// The width of the first line in s.
206 pub(crate) fn first_line_width(s: &str) -> usize {
207 unicode_str_width(s.splitn(2, '\n').next().unwrap_or(""))
210 /// The width of the last line in s.
212 pub(crate) fn last_line_width(s: &str) -> usize {
213 unicode_str_width(s.rsplitn(2, '\n').next().unwrap_or(""))
216 /// The total used width of the last line.
218 pub(crate) fn last_line_used_width(s: &str, offset: usize) -> usize {
219 if s.contains('\n') {
222 offset + unicode_str_width(s)
227 pub(crate) fn trimmed_last_line_width(s: &str) -> usize {
228 unicode_str_width(match s.rfind('\n') {
229 Some(n) => s[(n + 1)..].trim(),
235 pub(crate) fn last_line_extendable(s: &str) -> bool {
236 if s.ends_with("\"#") {
239 for c in s.chars().rev() {
241 '(' | ')' | ']' | '}' | '?' | '>' => continue,
243 _ if c.is_whitespace() => continue,
251 fn is_skip(meta_item: &MetaItem) -> bool {
252 match meta_item.kind {
253 MetaItemKind::Word => {
254 let path_str = pprust::path_to_string(&meta_item.path);
255 path_str == &*skip_annotation().as_str()
256 || path_str == &*depr_skip_annotation().as_str()
258 MetaItemKind::List(ref l) => {
259 meta_item.check_name(sym::cfg_attr) && l.len() == 2 && is_skip_nested(&l[1])
266 fn is_skip_nested(meta_item: &NestedMetaItem) -> bool {
268 NestedMetaItem::MetaItem(ref mi) => is_skip(mi),
269 NestedMetaItem::Literal(_) => false,
274 pub(crate) fn contains_skip(attrs: &[Attribute]) -> bool {
277 .any(|a| a.meta().map_or(false, |a| is_skip(&a)))
281 pub(crate) fn semicolon_for_expr(context: &RewriteContext<'_>, expr: &ast::Expr) -> bool {
283 ast::ExprKind::Ret(..) | ast::ExprKind::Continue(..) | ast::ExprKind::Break(..) => {
284 context.config.trailing_semicolon()
291 pub(crate) fn semicolon_for_stmt(context: &RewriteContext<'_>, stmt: &ast::Stmt) -> bool {
293 ast::StmtKind::Semi(ref expr) => match expr.kind {
294 ast::ExprKind::While(..) | ast::ExprKind::Loop(..) | ast::ExprKind::ForLoop(..) => {
297 ast::ExprKind::Break(..) | ast::ExprKind::Continue(..) | ast::ExprKind::Ret(..) => {
298 context.config.trailing_semicolon()
302 ast::StmtKind::Expr(..) => false,
308 pub(crate) fn stmt_expr(stmt: &ast::Stmt) -> Option<&ast::Expr> {
310 ast::StmtKind::Expr(ref expr) => Some(expr),
315 /// Returns the number of LF and CRLF respectively.
316 pub(crate) fn count_lf_crlf(input: &str) -> (usize, usize) {
319 let mut is_crlf = false;
320 for c in input.as_bytes() {
322 b'\r' => is_crlf = true,
323 b'\n' if is_crlf => crlf += 1,
325 _ => is_crlf = false,
331 pub(crate) fn count_newlines(input: &str) -> usize {
332 // Using bytes to omit UTF-8 decoding
333 bytecount::count(input.as_bytes(), b'\n')
336 // For format_missing and last_pos, need to use the source callsite (if applicable).
337 // Required as generated code spans aren't guaranteed to follow on from the last span.
338 macro_rules! source {
339 ($this:ident, $sp:expr) => {
340 $sp.source_callsite()
344 pub(crate) fn mk_sp(lo: BytePos, hi: BytePos) -> Span {
345 Span::new(lo, hi, SyntaxContext::root())
348 // Returns `true` if the given span does not intersect with file lines.
349 macro_rules! out_of_file_lines_range {
350 ($self:ident, $span:expr) => {
351 !$self.config.file_lines().is_all()
355 .intersects(&$self.parse_sess.lookup_line_range($span))
359 macro_rules! skip_out_of_file_lines_range {
360 ($self:ident, $span:expr) => {
361 if out_of_file_lines_range!($self, $span) {
367 macro_rules! skip_out_of_file_lines_range_visitor {
368 ($self:ident, $span:expr) => {
369 if out_of_file_lines_range!($self, $span) {
370 $self.push_rewrite($span, None);
376 // Wraps String in an Option. Returns Some when the string adheres to the
377 // Rewrite constraints defined for the Rewrite trait and None otherwise.
378 pub(crate) fn wrap_str(s: String, max_width: usize, shape: Shape) -> Option<String> {
379 if is_valid_str(&filter_normal_code(&s), max_width, shape) {
386 fn is_valid_str(snippet: &str, max_width: usize, shape: Shape) -> bool {
387 if !snippet.is_empty() {
388 // First line must fits with `shape.width`.
389 if first_line_width(snippet) > shape.width {
392 // If the snippet does not include newline, we are done.
393 if is_single_line(snippet) {
396 // The other lines must fit within the maximum width.
400 .any(|line| unicode_str_width(line) > max_width)
404 // A special check for the last line, since the caller may
405 // place trailing characters on this line.
406 if last_line_width(snippet) > shape.used_width() + shape.width {
414 pub(crate) fn colon_spaces(config: &Config) -> &'static str {
415 let before = config.space_before_colon();
416 let after = config.space_after_colon();
417 match (before, after) {
418 (true, true) => " : ",
419 (true, false) => " :",
420 (false, true) => ": ",
421 (false, false) => ":",
426 pub(crate) fn left_most_sub_expr(e: &ast::Expr) -> &ast::Expr {
428 ast::ExprKind::Call(ref e, _)
429 | ast::ExprKind::Binary(_, ref e, _)
430 | ast::ExprKind::Cast(ref e, _)
431 | ast::ExprKind::Type(ref e, _)
432 | ast::ExprKind::Assign(ref e, _, _)
433 | ast::ExprKind::AssignOp(_, ref e, _)
434 | ast::ExprKind::Field(ref e, _)
435 | ast::ExprKind::Index(ref e, _)
436 | ast::ExprKind::Range(Some(ref e), _, _)
437 | ast::ExprKind::Try(ref e) => left_most_sub_expr(e),
443 pub(crate) fn starts_with_newline(s: &str) -> bool {
444 s.starts_with('\n') || s.starts_with("\r\n")
448 pub(crate) fn first_line_ends_with(s: &str, c: char) -> bool {
449 s.lines().next().map_or(false, |l| l.ends_with(c))
452 // States whether an expression's last line exclusively consists of closing
453 // parens, braces, and brackets in its idiomatic formatting.
454 pub(crate) fn is_block_expr(context: &RewriteContext<'_>, expr: &ast::Expr, repr: &str) -> bool {
456 ast::ExprKind::MacCall(..)
457 | ast::ExprKind::Call(..)
458 | ast::ExprKind::MethodCall(..)
459 | ast::ExprKind::Array(..)
460 | ast::ExprKind::Struct(..)
461 | ast::ExprKind::While(..)
462 | ast::ExprKind::If(..)
463 | ast::ExprKind::Block(..)
464 | ast::ExprKind::Async(..)
465 | ast::ExprKind::Loop(..)
466 | ast::ExprKind::ForLoop(..)
467 | ast::ExprKind::TryBlock(..)
468 | ast::ExprKind::Match(..) => repr.contains('\n'),
469 ast::ExprKind::Paren(ref expr)
470 | ast::ExprKind::Binary(_, _, ref expr)
471 | ast::ExprKind::Index(_, ref expr)
472 | ast::ExprKind::Unary(_, ref expr)
473 | ast::ExprKind::Closure(_, _, _, _, ref expr, _)
474 | ast::ExprKind::Try(ref expr)
475 | ast::ExprKind::Yield(Some(ref expr)) => is_block_expr(context, expr, repr),
476 // This can only be a string lit
477 ast::ExprKind::Lit(_) => {
478 repr.contains('\n') && trimmed_last_line_width(repr) <= context.config.tab_spaces()
480 ast::ExprKind::AddrOf(..)
481 | ast::ExprKind::Assign(..)
482 | ast::ExprKind::AssignOp(..)
483 | ast::ExprKind::Await(..)
484 | ast::ExprKind::Box(..)
485 | ast::ExprKind::Break(..)
486 | ast::ExprKind::Cast(..)
487 | ast::ExprKind::Continue(..)
489 | ast::ExprKind::Field(..)
490 | ast::ExprKind::LlvmInlineAsm(..)
491 | ast::ExprKind::Let(..)
492 | ast::ExprKind::Path(..)
493 | ast::ExprKind::Range(..)
494 | ast::ExprKind::Repeat(..)
495 | ast::ExprKind::Ret(..)
496 | ast::ExprKind::Tup(..)
497 | ast::ExprKind::Type(..)
498 | ast::ExprKind::Yield(None) => false,
502 /// Removes trailing spaces from the specified snippet. We do not remove spaces
503 /// inside strings or comments.
504 pub(crate) fn remove_trailing_white_spaces(text: &str) -> String {
505 let mut buffer = String::with_capacity(text.len());
506 let mut space_buffer = String::with_capacity(128);
507 for (char_kind, c) in CharClasses::new(text.chars()) {
510 if char_kind == FullCodeCharKind::InString {
511 buffer.push_str(&space_buffer);
513 space_buffer.clear();
516 _ if c.is_whitespace() => {
517 space_buffer.push(c);
520 if !space_buffer.is_empty() {
521 buffer.push_str(&space_buffer);
522 space_buffer.clear();
531 /// Indent each line according to the specified `indent`.
534 /// ```rust,compile_fail
548 /// ```rust,compile_fail
559 pub(crate) fn trim_left_preserve_layout(
563 ) -> Option<String> {
564 let mut lines = LineClasses::new(orig);
565 let first_line = lines.next().map(|(_, s)| s.trim_end().to_owned())?;
566 let mut trimmed_lines = Vec::with_capacity(16);
568 let mut veto_trim = false;
569 let min_prefix_space_width = lines
570 .filter_map(|(kind, line)| {
571 let mut trimmed = true;
572 let prefix_space_width = if is_empty_line(&line) {
575 Some(get_prefix_space_width(config, &line))
578 // just InString{Commented} in order to allow the start of a string to be indented
579 let new_veto_trim_value = (kind == FullCodeCharKind::InString
580 || (config.version() == Version::Two
581 && kind == FullCodeCharKind::InStringCommented))
582 && !line.ends_with('\\');
583 let line = if veto_trim || new_veto_trim_value {
584 veto_trim = new_veto_trim_value;
588 line.trim().to_owned()
590 trimmed_lines.push((trimmed, line, prefix_space_width));
592 // Because there is a veto against trimming and indenting lines within a string,
593 // such lines should not be taken into account when computing the minimum.
595 FullCodeCharKind::InStringCommented | FullCodeCharKind::EndStringCommented
596 if config.version() == Version::Two =>
600 FullCodeCharKind::InString | FullCodeCharKind::EndString => None,
601 _ => prefix_space_width,
612 |&(trimmed, ref line, prefix_space_width)| match prefix_space_width {
613 _ if !trimmed => line.to_owned(),
614 Some(original_indent_width) => {
615 let new_indent_width = indent.width()
616 + original_indent_width.saturating_sub(min_prefix_space_width);
617 let new_indent = Indent::from_width(config, new_indent_width);
618 format!("{}{}", new_indent.to_string(config), line)
620 None => String::new(),
628 /// Based on the given line, determine if the next line can be indented or not.
629 /// This allows to preserve the indentation of multi-line literals.
630 pub(crate) fn indent_next_line(kind: FullCodeCharKind, _line: &str, config: &Config) -> bool {
631 !(kind.is_string() || (config.version() == Version::Two && kind.is_commented_string()))
634 pub(crate) fn is_empty_line(s: &str) -> bool {
635 s.is_empty() || s.chars().all(char::is_whitespace)
638 fn get_prefix_space_width(config: &Config, s: &str) -> usize {
643 '\t' => width += config.tab_spaces(),
650 pub(crate) trait NodeIdExt {
654 impl NodeIdExt for NodeId {
655 fn root() -> NodeId {
656 NodeId::placeholder_from_expn_id(ExpnId::root())
660 pub(crate) fn unicode_str_width(s: &str) -> usize {
669 fn test_remove_trailing_white_spaces() {
670 let s = " r#\"\n test\n \"#";
671 assert_eq!(remove_trailing_white_spaces(&s), s);
675 fn test_trim_left_preserve_layout() {
676 let s = "aaa\n\tbbb\n ccc";
677 let config = Config::default();
678 let indent = Indent::new(4, 0);
680 trim_left_preserve_layout(&s, indent, &config),
681 Some("aaa\n bbb\n ccc".to_string())