1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
13 use rustc_target::spec::abi;
15 self, Attribute, CrateSugar, MetaItem, MetaItemKind, NestedMetaItem, NestedMetaItemKind, Path,
16 Visibility, VisibilityKind,
18 use syntax::codemap::{BytePos, Span, NO_EXPANSION};
21 use comment::filter_normal_code;
22 use rewrite::RewriteContext;
25 pub const DEPR_SKIP_ANNOTATION: &str = "rustfmt_skip";
26 pub const SKIP_ANNOTATION: &str = "rustfmt::skip";
28 pub fn rewrite_ident<'a>(context: &'a RewriteContext, ident: ast::Ident) -> &'a str {
29 context.snippet(ident.span)
32 // Computes the length of a string's last line, minus offset.
33 pub fn extra_offset(text: &str, shape: Shape) -> usize {
34 match text.rfind('\n') {
35 // 1 for newline character
36 Some(idx) => text.len().saturating_sub(idx + 1 + shape.used_width()),
41 pub fn is_same_visibility(a: &Visibility, b: &Visibility) -> bool {
42 match (&a.node, &b.node) {
44 VisibilityKind::Restricted { path: p, .. },
45 VisibilityKind::Restricted { path: q, .. },
46 ) => format!("{}", p) == format!("{}", q),
47 (VisibilityKind::Public, VisibilityKind::Public)
48 | (VisibilityKind::Inherited, VisibilityKind::Inherited)
50 VisibilityKind::Crate(CrateSugar::PubCrate),
51 VisibilityKind::Crate(CrateSugar::PubCrate),
54 VisibilityKind::Crate(CrateSugar::JustCrate),
55 VisibilityKind::Crate(CrateSugar::JustCrate),
61 // Uses Cow to avoid allocating in the common cases.
62 pub fn format_visibility(context: &RewriteContext, vis: &Visibility) -> Cow<'static, str> {
64 VisibilityKind::Public => Cow::from("pub "),
65 VisibilityKind::Inherited => Cow::from(""),
66 VisibilityKind::Crate(CrateSugar::PubCrate) => Cow::from("pub(crate) "),
67 VisibilityKind::Crate(CrateSugar::JustCrate) => Cow::from("crate "),
68 VisibilityKind::Restricted { ref path, .. } => {
69 let Path { ref segments, .. } = **path;
70 let mut segments_iter = segments.iter().map(|seg| rewrite_ident(context, seg.ident));
74 .expect("Non-global path in pub(restricted)?");
76 let is_keyword = |s: &str| s == "self" || s == "super";
77 let path = segments_iter.collect::<Vec<_>>().join("::");
78 let in_str = if is_keyword(&path) { "" } else { "in " };
80 Cow::from(format!("pub({}{}) ", in_str, path))
86 pub fn format_async(is_async: ast::IsAsync) -> &'static str {
88 ast::IsAsync::Async { .. } => "async ",
89 ast::IsAsync::NotAsync => "",
94 pub fn format_constness(constness: ast::Constness) -> &'static str {
96 ast::Constness::Const => "const ",
97 ast::Constness::NotConst => "",
102 pub fn format_defaultness(defaultness: ast::Defaultness) -> &'static str {
104 ast::Defaultness::Default => "default ",
105 ast::Defaultness::Final => "",
110 pub fn format_unsafety(unsafety: ast::Unsafety) -> &'static str {
112 ast::Unsafety::Unsafe => "unsafe ",
113 ast::Unsafety::Normal => "",
118 pub fn format_auto(is_auto: ast::IsAuto) -> &'static str {
120 ast::IsAuto::Yes => "auto ",
121 ast::IsAuto::No => "",
126 pub fn format_mutability(mutability: ast::Mutability) -> &'static str {
128 ast::Mutability::Mutable => "mut ",
129 ast::Mutability::Immutable => "",
134 pub fn format_abi(abi: abi::Abi, explicit_abi: bool, is_mod: bool) -> Cow<'static, str> {
135 if abi == abi::Abi::Rust && !is_mod {
137 } else if abi == abi::Abi::C && !explicit_abi {
140 Cow::from(format!("extern {} ", abi))
145 // Transform `Vec<syntax::ptr::P<T>>` into `Vec<&T>`
146 pub fn ptr_vec_to_ref_vec<T>(vec: &[ptr::P<T>]) -> Vec<&T> {
147 vec.iter().map(|x| &**x).collect::<Vec<_>>()
151 pub fn filter_attributes(attrs: &[ast::Attribute], style: ast::AttrStyle) -> Vec<ast::Attribute> {
154 .filter(|a| a.style == style)
160 pub fn inner_attributes(attrs: &[ast::Attribute]) -> Vec<ast::Attribute> {
161 filter_attributes(attrs, ast::AttrStyle::Inner)
165 pub fn outer_attributes(attrs: &[ast::Attribute]) -> Vec<ast::Attribute> {
166 filter_attributes(attrs, ast::AttrStyle::Outer)
170 pub fn is_single_line(s: &str) -> bool {
171 s.chars().find(|&c| c == '\n').is_none()
175 pub fn first_line_contains_single_line_comment(s: &str) -> bool {
176 s.lines().next().map_or(false, |l| l.contains("//"))
180 pub fn last_line_contains_single_line_comment(s: &str) -> bool {
181 s.lines().last().map_or(false, |l| l.contains("//"))
185 pub fn is_attributes_extendable(attrs_str: &str) -> bool {
186 !attrs_str.contains('\n') && !last_line_contains_single_line_comment(attrs_str)
189 // The width of the first line in s.
191 pub fn first_line_width(s: &str) -> usize {
198 // The width of the last line in s.
200 pub fn last_line_width(s: &str) -> usize {
201 match s.rfind('\n') {
202 Some(n) => s.len() - n - 1,
207 // The total used width of the last line.
209 pub fn last_line_used_width(s: &str, offset: usize) -> usize {
210 if s.contains('\n') {
218 pub fn trimmed_last_line_width(s: &str) -> usize {
219 match s.rfind('\n') {
220 Some(n) => s[(n + 1)..].trim().len(),
221 None => s.trim().len(),
226 pub fn last_line_extendable(s: &str) -> bool {
227 if s.ends_with("\"#") {
230 for c in s.chars().rev() {
232 '(' | ')' | ']' | '}' | '?' | '>' => continue,
234 _ if c.is_whitespace() => continue,
242 fn is_skip(meta_item: &MetaItem) -> bool {
243 match meta_item.node {
244 MetaItemKind::Word => {
245 let path_str = meta_item.ident.to_string();
246 path_str == SKIP_ANNOTATION || path_str == DEPR_SKIP_ANNOTATION
248 MetaItemKind::List(ref l) => {
249 meta_item.name() == "cfg_attr" && l.len() == 2 && is_skip_nested(&l[1])
256 fn is_skip_nested(meta_item: &NestedMetaItem) -> bool {
257 match meta_item.node {
258 NestedMetaItemKind::MetaItem(ref mi) => is_skip(mi),
259 NestedMetaItemKind::Literal(_) => false,
264 pub fn contains_skip(attrs: &[Attribute]) -> bool {
267 .any(|a| a.meta().map_or(false, |a| is_skip(&a)))
271 pub fn semicolon_for_expr(context: &RewriteContext, expr: &ast::Expr) -> bool {
273 ast::ExprKind::Ret(..) | ast::ExprKind::Continue(..) | ast::ExprKind::Break(..) => {
274 context.config.trailing_semicolon()
281 pub fn semicolon_for_stmt(context: &RewriteContext, stmt: &ast::Stmt) -> bool {
283 ast::StmtKind::Semi(ref expr) => match expr.node {
284 ast::ExprKind::While(..)
285 | ast::ExprKind::WhileLet(..)
286 | ast::ExprKind::Loop(..)
287 | ast::ExprKind::ForLoop(..) => false,
288 ast::ExprKind::Break(..) | ast::ExprKind::Continue(..) | ast::ExprKind::Ret(..) => {
289 context.config.trailing_semicolon()
293 ast::StmtKind::Expr(..) => false,
299 pub fn stmt_expr(stmt: &ast::Stmt) -> Option<&ast::Expr> {
301 ast::StmtKind::Expr(ref expr) => Some(expr),
307 pub fn count_newlines(input: &str) -> usize {
308 // Using `as_bytes` to omit UTF-8 decoding
309 input.as_bytes().iter().filter(|&&c| c == b'\n').count()
312 // For format_missing and last_pos, need to use the source callsite (if applicable).
313 // Required as generated code spans aren't guaranteed to follow on from the last span.
314 macro_rules! source {
315 ($this:ident, $sp:expr) => {
316 $sp.source_callsite()
320 pub fn mk_sp(lo: BytePos, hi: BytePos) -> Span {
321 Span::new(lo, hi, NO_EXPANSION)
324 // Return true if the given span does not intersect with file lines.
325 macro_rules! out_of_file_lines_range {
326 ($self:ident, $span:expr) => {
327 !$self.config.file_lines().is_all() && !$self
330 .intersects(&$self.codemap.lookup_line_range($span))
334 macro_rules! skip_out_of_file_lines_range {
335 ($self:ident, $span:expr) => {
336 if out_of_file_lines_range!($self, $span) {
342 macro_rules! skip_out_of_file_lines_range_visitor {
343 ($self:ident, $span:expr) => {
344 if out_of_file_lines_range!($self, $span) {
345 $self.push_rewrite($span, None);
351 // Wraps String in an Option. Returns Some when the string adheres to the
352 // Rewrite constraints defined for the Rewrite trait and None otherwise.
353 pub fn wrap_str(s: String, max_width: usize, shape: Shape) -> Option<String> {
354 if is_valid_str(&filter_normal_code(&s), max_width, shape) {
361 fn is_valid_str(snippet: &str, max_width: usize, shape: Shape) -> bool {
362 if !snippet.is_empty() {
363 // First line must fits with `shape.width`.
364 if first_line_width(snippet) > shape.width {
367 // If the snippet does not include newline, we are done.
368 if first_line_width(snippet) == snippet.len() {
371 // The other lines must fit within the maximum width.
372 if snippet.lines().skip(1).any(|line| line.len() > max_width) {
375 // A special check for the last line, since the caller may
376 // place trailing characters on this line.
377 if last_line_width(snippet) > shape.used_width() + shape.width {
385 pub fn colon_spaces(before: bool, after: bool) -> &'static str {
386 match (before, after) {
387 (true, true) => " : ",
388 (true, false) => " :",
389 (false, true) => ": ",
390 (false, false) => ":",
395 pub fn left_most_sub_expr(e: &ast::Expr) -> &ast::Expr {
397 ast::ExprKind::Call(ref e, _)
398 | ast::ExprKind::Binary(_, ref e, _)
399 | ast::ExprKind::Cast(ref e, _)
400 | ast::ExprKind::Type(ref e, _)
401 | ast::ExprKind::Assign(ref e, _)
402 | ast::ExprKind::AssignOp(_, ref e, _)
403 | ast::ExprKind::Field(ref e, _)
404 | ast::ExprKind::Index(ref e, _)
405 | ast::ExprKind::Range(Some(ref e), _, _)
406 | ast::ExprKind::Try(ref e) => left_most_sub_expr(e),
412 pub fn starts_with_newline(s: &str) -> bool {
413 s.starts_with('\n') || s.starts_with("\r\n")
417 pub fn first_line_ends_with(s: &str, c: char) -> bool {
418 s.lines().next().map_or(false, |l| l.ends_with(c))