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 rewrite::RewriteContext;
24 pub const DEPR_SKIP_ANNOTATION: &str = "rustfmt_skip";
25 pub const SKIP_ANNOTATION: &str = "rustfmt::skip";
27 pub fn rewrite_ident<'a>(context: &'a RewriteContext, ident: ast::Ident) -> &'a str {
28 context.snippet(ident.span)
31 // Computes the length of a string's last line, minus offset.
32 pub 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 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 ) => format!("{}", p) == format!("{}", 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 fn format_visibility(context: &RewriteContext, vis: &Visibility) -> Cow<'static, str> {
63 VisibilityKind::Public => Cow::from("pub "),
64 VisibilityKind::Inherited => Cow::from(""),
65 VisibilityKind::Crate(CrateSugar::PubCrate) => Cow::from("pub(crate) "),
66 VisibilityKind::Crate(CrateSugar::JustCrate) => Cow::from("crate "),
67 VisibilityKind::Restricted { ref path, .. } => {
68 let Path { ref segments, .. } = **path;
69 let mut segments_iter = segments.iter().map(|seg| rewrite_ident(context, seg.ident));
73 .expect("Non-global path in pub(restricted)?");
75 let is_keyword = |s: &str| s == "self" || s == "super";
76 let path = segments_iter.collect::<Vec<_>>().join("::");
77 let in_str = if is_keyword(&path) { "" } else { "in " };
79 Cow::from(format!("pub({}{}) ", in_str, path))
85 pub fn format_async(is_async: ast::IsAsync) -> &'static str {
87 ast::IsAsync::Async { .. } => "async ",
88 ast::IsAsync::NotAsync => "",
93 pub fn format_constness(constness: ast::Constness) -> &'static str {
95 ast::Constness::Const => "const ",
96 ast::Constness::NotConst => "",
101 pub fn format_defaultness(defaultness: ast::Defaultness) -> &'static str {
103 ast::Defaultness::Default => "default ",
104 ast::Defaultness::Final => "",
109 pub fn format_unsafety(unsafety: ast::Unsafety) -> &'static str {
111 ast::Unsafety::Unsafe => "unsafe ",
112 ast::Unsafety::Normal => "",
117 pub fn format_auto(is_auto: ast::IsAuto) -> &'static str {
119 ast::IsAuto::Yes => "auto ",
120 ast::IsAuto::No => "",
125 pub fn format_mutability(mutability: ast::Mutability) -> &'static str {
127 ast::Mutability::Mutable => "mut ",
128 ast::Mutability::Immutable => "",
133 pub fn format_abi(abi: abi::Abi, explicit_abi: bool, is_mod: bool) -> Cow<'static, str> {
134 if abi == abi::Abi::Rust && !is_mod {
136 } else if abi == abi::Abi::C && !explicit_abi {
139 Cow::from(format!("extern {} ", abi))
144 // Transform `Vec<syntax::ptr::P<T>>` into `Vec<&T>`
145 pub fn ptr_vec_to_ref_vec<T>(vec: &[ptr::P<T>]) -> Vec<&T> {
146 vec.iter().map(|x| &**x).collect::<Vec<_>>()
150 pub fn filter_attributes(attrs: &[ast::Attribute], style: ast::AttrStyle) -> Vec<ast::Attribute> {
153 .filter(|a| a.style == style)
159 pub fn inner_attributes(attrs: &[ast::Attribute]) -> Vec<ast::Attribute> {
160 filter_attributes(attrs, ast::AttrStyle::Inner)
164 pub fn outer_attributes(attrs: &[ast::Attribute]) -> Vec<ast::Attribute> {
165 filter_attributes(attrs, ast::AttrStyle::Outer)
169 pub fn is_single_line(s: &str) -> bool {
170 s.chars().find(|&c| c == '\n').is_none()
174 pub fn first_line_contains_single_line_comment(s: &str) -> bool {
175 s.lines().next().map_or(false, |l| l.contains("//"))
179 pub fn last_line_contains_single_line_comment(s: &str) -> bool {
180 s.lines().last().map_or(false, |l| l.contains("//"))
184 pub fn is_attributes_extendable(attrs_str: &str) -> bool {
185 !attrs_str.contains('\n') && !last_line_contains_single_line_comment(attrs_str)
188 // The width of the first line in s.
190 pub fn first_line_width(s: &str) -> usize {
197 // The width of the last line in s.
199 pub fn last_line_width(s: &str) -> usize {
200 match s.rfind('\n') {
201 Some(n) => s.len() - n - 1,
206 // The total used width of the last line.
208 pub fn last_line_used_width(s: &str, offset: usize) -> usize {
209 if s.contains('\n') {
217 pub fn trimmed_last_line_width(s: &str) -> usize {
218 match s.rfind('\n') {
219 Some(n) => s[(n + 1)..].trim().len(),
220 None => s.trim().len(),
225 pub fn last_line_extendable(s: &str) -> bool {
226 if s.ends_with("\"#") {
229 for c in s.chars().rev() {
231 '(' | ')' | ']' | '}' | '?' | '>' => continue,
233 _ if c.is_whitespace() => continue,
241 fn is_skip(meta_item: &MetaItem) -> bool {
242 match meta_item.node {
243 MetaItemKind::Word => {
244 let path_str = meta_item.ident.to_string();
245 path_str == SKIP_ANNOTATION || path_str == DEPR_SKIP_ANNOTATION
247 MetaItemKind::List(ref l) => {
248 meta_item.name() == "cfg_attr" && l.len() == 2 && is_skip_nested(&l[1])
255 fn is_skip_nested(meta_item: &NestedMetaItem) -> bool {
256 match meta_item.node {
257 NestedMetaItemKind::MetaItem(ref mi) => is_skip(mi),
258 NestedMetaItemKind::Literal(_) => false,
263 pub fn contains_skip(attrs: &[Attribute]) -> bool {
266 .any(|a| a.meta().map_or(false, |a| is_skip(&a)))
270 pub fn semicolon_for_expr(context: &RewriteContext, expr: &ast::Expr) -> bool {
272 ast::ExprKind::Ret(..) | ast::ExprKind::Continue(..) | ast::ExprKind::Break(..) => {
273 context.config.trailing_semicolon()
280 pub fn semicolon_for_stmt(context: &RewriteContext, stmt: &ast::Stmt) -> bool {
282 ast::StmtKind::Semi(ref expr) => match expr.node {
283 ast::ExprKind::While(..)
284 | ast::ExprKind::WhileLet(..)
285 | ast::ExprKind::Loop(..)
286 | ast::ExprKind::ForLoop(..) => false,
287 ast::ExprKind::Break(..) | ast::ExprKind::Continue(..) | ast::ExprKind::Ret(..) => {
288 context.config.trailing_semicolon()
292 ast::StmtKind::Expr(..) => false,
298 pub fn stmt_expr(stmt: &ast::Stmt) -> Option<&ast::Expr> {
300 ast::StmtKind::Expr(ref expr) => Some(expr),
306 pub fn count_newlines(input: &str) -> usize {
307 // Using `as_bytes` to omit UTF-8 decoding
308 input.as_bytes().iter().filter(|&&c| c == b'\n').count()
311 // For format_missing and last_pos, need to use the source callsite (if applicable).
312 // Required as generated code spans aren't guaranteed to follow on from the last span.
313 macro_rules! source {
314 ($this:ident, $sp:expr) => {
315 $sp.source_callsite()
319 pub fn mk_sp(lo: BytePos, hi: BytePos) -> Span {
320 Span::new(lo, hi, NO_EXPANSION)
323 // Return true if the given span does not intersect with file lines.
324 macro_rules! out_of_file_lines_range {
325 ($self:ident, $span:expr) => {
326 !$self.config.file_lines().is_all() && !$self
329 .intersects(&$self.codemap.lookup_line_range($span))
333 macro_rules! skip_out_of_file_lines_range {
334 ($self:ident, $span:expr) => {
335 if out_of_file_lines_range!($self, $span) {
341 macro_rules! skip_out_of_file_lines_range_visitor {
342 ($self:ident, $span:expr) => {
343 if out_of_file_lines_range!($self, $span) {
344 $self.push_rewrite($span, None);
350 // Wraps String in an Option. Returns Some when the string adheres to the
351 // Rewrite constraints defined for the Rewrite trait and None otherwise.
352 pub fn wrap_str(s: String, max_width: usize, shape: Shape) -> Option<String> {
353 if is_valid_str(&s, max_width, shape) {
360 fn is_valid_str(snippet: &str, max_width: usize, shape: Shape) -> bool {
361 if !snippet.is_empty() {
362 // First line must fits with `shape.width`.
363 if first_line_width(snippet) > shape.width {
366 // If the snippet does not include newline, we are done.
367 if first_line_width(snippet) == snippet.len() {
370 // The other lines must fit within the maximum width.
371 if snippet.lines().skip(1).any(|line| line.len() > max_width) {
374 // A special check for the last line, since the caller may
375 // place trailing characters on this line.
376 if last_line_width(snippet) > shape.used_width() + shape.width {
384 pub fn colon_spaces(before: bool, after: bool) -> &'static str {
385 match (before, after) {
386 (true, true) => " : ",
387 (true, false) => " :",
388 (false, true) => ": ",
389 (false, false) => ":",
394 pub fn left_most_sub_expr(e: &ast::Expr) -> &ast::Expr {
396 ast::ExprKind::Call(ref e, _)
397 | ast::ExprKind::Binary(_, ref e, _)
398 | ast::ExprKind::Cast(ref e, _)
399 | ast::ExprKind::Type(ref e, _)
400 | ast::ExprKind::Assign(ref e, _)
401 | ast::ExprKind::AssignOp(_, ref e, _)
402 | ast::ExprKind::Field(ref e, _)
403 | ast::ExprKind::Index(ref e, _)
404 | ast::ExprKind::Range(Some(ref e), _, _)
405 | ast::ExprKind::Try(ref e) => left_most_sub_expr(e),
411 pub fn starts_with_newline(s: &str) -> bool {
412 s.starts_with('\n') || s.starts_with("\r\n")
416 pub fn first_line_ends_with(s: &str, c: char) -> bool {
417 s.lines().next().map_or(false, |l| l.ends_with(c))