1 //! HTML formatting module
2 //!
3 //! This module contains a large number of `fmt::Display` implementations for
4 //! various types in `rustdoc::clean`. These implementations all currently
5 //! assume that HTML output is desired, although it may be possible to redesign
6 //! them in the future to instead emit any format desired.
7
8 use std::cell::Cell;
9 use std::fmt;
10 use std::iter;
11
12 use rustc_attr::{ConstStability, StabilityLevel};
13 use rustc_data_structures::captures::Captures;
14 use rustc_data_structures::fx::FxHashSet;
15 use rustc_hir as hir;
16 use rustc_hir::def::DefKind;
17 use rustc_hir::def_id::DefId;
18 use rustc_middle::ty;
19 use rustc_middle::ty::DefIdTree;
20 use rustc_middle::ty::TyCtxt;
21 use rustc_span::def_id::CRATE_DEF_INDEX;
22 use rustc_target::spec::abi::Abi;
23
24 use crate::clean::{self, utils::find_nearest_parent_module, ExternalCrate, ItemId, PrimitiveType};
25 use crate::formats::item_type::ItemType;
26 use crate::html::escape::Escape;
27 use crate::html::render::cache::ExternalLocation;
28 use crate::html::render::Context;
29
30 crate trait Print {
print(self, buffer: &mut Buffer)31 fn print(self, buffer: &mut Buffer);
32 }
33
34 impl<F> Print for F
35 where
36 F: FnOnce(&mut Buffer),
37 {
print(self, buffer: &mut Buffer)38 fn print(self, buffer: &mut Buffer) {
39 (self)(buffer)
40 }
41 }
42
43 impl Print for String {
print(self, buffer: &mut Buffer)44 fn print(self, buffer: &mut Buffer) {
45 buffer.write_str(&self);
46 }
47 }
48
49 impl Print for &'_ str {
print(self, buffer: &mut Buffer)50 fn print(self, buffer: &mut Buffer) {
51 buffer.write_str(self);
52 }
53 }
54
55 #[derive(Debug, Clone)]
56 crate struct Buffer {
57 for_html: bool,
58 buffer: String,
59 }
60
61 impl Buffer {
empty_from(v: &Buffer) -> Buffer62 crate fn empty_from(v: &Buffer) -> Buffer {
63 Buffer { for_html: v.for_html, buffer: String::new() }
64 }
65
html() -> Buffer66 crate fn html() -> Buffer {
67 Buffer { for_html: true, buffer: String::new() }
68 }
69
new() -> Buffer70 crate fn new() -> Buffer {
71 Buffer { for_html: false, buffer: String::new() }
72 }
73
is_empty(&self) -> bool74 crate fn is_empty(&self) -> bool {
75 self.buffer.is_empty()
76 }
77
into_inner(self) -> String78 crate fn into_inner(self) -> String {
79 self.buffer
80 }
81
insert_str(&mut self, idx: usize, s: &str)82 crate fn insert_str(&mut self, idx: usize, s: &str) {
83 self.buffer.insert_str(idx, s);
84 }
85
push_str(&mut self, s: &str)86 crate fn push_str(&mut self, s: &str) {
87 self.buffer.push_str(s);
88 }
89
push_buffer(&mut self, other: Buffer)90 crate fn push_buffer(&mut self, other: Buffer) {
91 self.buffer.push_str(&other.buffer);
92 }
93
94 // Intended for consumption by write! and writeln! (std::fmt) but without
95 // the fmt::Result return type imposed by fmt::Write (and avoiding the trait
96 // import).
write_str(&mut self, s: &str)97 crate fn write_str(&mut self, s: &str) {
98 self.buffer.push_str(s);
99 }
100
101 // Intended for consumption by write! and writeln! (std::fmt) but without
102 // the fmt::Result return type imposed by fmt::Write (and avoiding the trait
103 // import).
write_fmt(&mut self, v: fmt::Arguments<'_>)104 crate fn write_fmt(&mut self, v: fmt::Arguments<'_>) {
105 use fmt::Write;
106 self.buffer.write_fmt(v).unwrap();
107 }
108
to_display<T: Print>(mut self, t: T) -> String109 crate fn to_display<T: Print>(mut self, t: T) -> String {
110 t.print(&mut self);
111 self.into_inner()
112 }
113
is_for_html(&self) -> bool114 crate fn is_for_html(&self) -> bool {
115 self.for_html
116 }
117
reserve(&mut self, additional: usize)118 crate fn reserve(&mut self, additional: usize) {
119 self.buffer.reserve(additional)
120 }
121 }
122
comma_sep<T: fmt::Display>(items: impl Iterator<Item = T>) -> impl fmt::Display123 fn comma_sep<T: fmt::Display>(items: impl Iterator<Item = T>) -> impl fmt::Display {
124 display_fn(move |f| {
125 for (i, item) in items.enumerate() {
126 if i != 0 {
127 write!(f, ", ")?;
128 }
129 fmt::Display::fmt(&item, f)?;
130 }
131 Ok(())
132 })
133 }
134
print_generic_bounds<'a, 'tcx: 'a>( bounds: &'a [clean::GenericBound], cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>135 crate fn print_generic_bounds<'a, 'tcx: 'a>(
136 bounds: &'a [clean::GenericBound],
137 cx: &'a Context<'tcx>,
138 ) -> impl fmt::Display + 'a + Captures<'tcx> {
139 display_fn(move |f| {
140 let mut bounds_dup = FxHashSet::default();
141
142 for (i, bound) in
143 bounds.iter().filter(|b| bounds_dup.insert(b.print(cx).to_string())).enumerate()
144 {
145 if i > 0 {
146 f.write_str(" + ")?;
147 }
148 fmt::Display::fmt(&bound.print(cx), f)?;
149 }
150 Ok(())
151 })
152 }
153
154 impl clean::GenericParamDef {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>155 crate fn print<'a, 'tcx: 'a>(
156 &'a self,
157 cx: &'a Context<'tcx>,
158 ) -> impl fmt::Display + 'a + Captures<'tcx> {
159 display_fn(move |f| match &self.kind {
160 clean::GenericParamDefKind::Lifetime { outlives } => {
161 write!(f, "{}", self.name)?;
162
163 if !outlives.is_empty() {
164 f.write_str(": ")?;
165 for (i, lt) in outlives.iter().enumerate() {
166 if i != 0 {
167 f.write_str(" + ")?;
168 }
169 write!(f, "{}", lt.print())?;
170 }
171 }
172
173 Ok(())
174 }
175 clean::GenericParamDefKind::Type { bounds, default, .. } => {
176 f.write_str(&*self.name.as_str())?;
177
178 if !bounds.is_empty() {
179 if f.alternate() {
180 write!(f, ": {:#}", print_generic_bounds(bounds, cx))?;
181 } else {
182 write!(f, ": {}", print_generic_bounds(bounds, cx))?;
183 }
184 }
185
186 if let Some(ref ty) = default {
187 if f.alternate() {
188 write!(f, " = {:#}", ty.print(cx))?;
189 } else {
190 write!(f, " = {}", ty.print(cx))?;
191 }
192 }
193
194 Ok(())
195 }
196 clean::GenericParamDefKind::Const { ty, default, .. } => {
197 if f.alternate() {
198 write!(f, "const {}: {:#}", self.name, ty.print(cx))?;
199 } else {
200 write!(f, "const {}: {}", self.name, ty.print(cx))?;
201 }
202
203 if let Some(default) = default {
204 if f.alternate() {
205 write!(f, " = {:#}", default)?;
206 } else {
207 write!(f, " = {}", default)?;
208 }
209 }
210
211 Ok(())
212 }
213 })
214 }
215 }
216
217 impl clean::Generics {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>218 crate fn print<'a, 'tcx: 'a>(
219 &'a self,
220 cx: &'a Context<'tcx>,
221 ) -> impl fmt::Display + 'a + Captures<'tcx> {
222 display_fn(move |f| {
223 let real_params =
224 self.params.iter().filter(|p| !p.is_synthetic_type_param()).collect::<Vec<_>>();
225 if real_params.is_empty() {
226 return Ok(());
227 }
228 if f.alternate() {
229 write!(f, "<{:#}>", comma_sep(real_params.iter().map(|g| g.print(cx))))
230 } else {
231 write!(f, "<{}>", comma_sep(real_params.iter().map(|g| g.print(cx))))
232 }
233 })
234 }
235 }
236
237 /// * The Generics from which to emit a where-clause.
238 /// * The number of spaces to indent each line with.
239 /// * Whether the where-clause needs to add a comma and newline after the last bound.
print_where_clause<'a, 'tcx: 'a>( gens: &'a clean::Generics, cx: &'a Context<'tcx>, indent: usize, end_newline: bool, ) -> impl fmt::Display + 'a + Captures<'tcx>240 crate fn print_where_clause<'a, 'tcx: 'a>(
241 gens: &'a clean::Generics,
242 cx: &'a Context<'tcx>,
243 indent: usize,
244 end_newline: bool,
245 ) -> impl fmt::Display + 'a + Captures<'tcx> {
246 display_fn(move |f| {
247 if gens.where_predicates.is_empty() {
248 return Ok(());
249 }
250 let mut clause = String::new();
251 if f.alternate() {
252 clause.push_str(" where");
253 } else {
254 if end_newline {
255 clause.push_str(" <span class=\"where fmt-newline\">where");
256 } else {
257 clause.push_str(" <span class=\"where\">where");
258 }
259 }
260 for (i, pred) in gens.where_predicates.iter().enumerate() {
261 if f.alternate() {
262 clause.push(' ');
263 } else {
264 clause.push_str("<br>");
265 }
266
267 match pred {
268 clean::WherePredicate::BoundPredicate { ty, bounds, bound_params } => {
269 let bounds = bounds;
270 let for_prefix = match bound_params.len() {
271 0 => String::new(),
272 _ if f.alternate() => {
273 format!(
274 "for<{:#}> ",
275 comma_sep(bound_params.iter().map(|lt| lt.print()))
276 )
277 }
278 _ => format!(
279 "for<{}> ",
280 comma_sep(bound_params.iter().map(|lt| lt.print()))
281 ),
282 };
283
284 if f.alternate() {
285 clause.push_str(&format!(
286 "{}{:#}: {:#}",
287 for_prefix,
288 ty.print(cx),
289 print_generic_bounds(bounds, cx)
290 ));
291 } else {
292 clause.push_str(&format!(
293 "{}{}: {}",
294 for_prefix,
295 ty.print(cx),
296 print_generic_bounds(bounds, cx)
297 ));
298 }
299 }
300 clean::WherePredicate::RegionPredicate { lifetime, bounds } => {
301 clause.push_str(&format!(
302 "{}: {}",
303 lifetime.print(),
304 bounds
305 .iter()
306 .map(|b| b.print(cx).to_string())
307 .collect::<Vec<_>>()
308 .join(" + ")
309 ));
310 }
311 clean::WherePredicate::EqPredicate { lhs, rhs } => {
312 if f.alternate() {
313 clause.push_str(&format!("{:#} == {:#}", lhs.print(cx), rhs.print(cx),));
314 } else {
315 clause.push_str(&format!("{} == {}", lhs.print(cx), rhs.print(cx),));
316 }
317 }
318 }
319
320 if i < gens.where_predicates.len() - 1 || end_newline {
321 clause.push(',');
322 }
323 }
324
325 if end_newline {
326 // add a space so stripping <br> tags and breaking spaces still renders properly
327 if f.alternate() {
328 clause.push(' ');
329 } else {
330 clause.push_str(" ");
331 }
332 }
333
334 if !f.alternate() {
335 clause.push_str("</span>");
336 let padding = " ".repeat(indent + 4);
337 clause = clause.replace("<br>", &format!("<br>{}", padding));
338 clause.insert_str(0, &" ".repeat(indent.saturating_sub(1)));
339 if !end_newline {
340 clause.insert_str(0, "<br>");
341 }
342 }
343 write!(f, "{}", clause)
344 })
345 }
346
347 impl clean::Lifetime {
print(&self) -> impl fmt::Display + '_348 crate fn print(&self) -> impl fmt::Display + '_ {
349 self.get_ref()
350 }
351 }
352
353 impl clean::Constant {
print(&self, tcx: TyCtxt<'_>) -> impl fmt::Display + '_354 crate fn print(&self, tcx: TyCtxt<'_>) -> impl fmt::Display + '_ {
355 let expr = self.expr(tcx);
356 display_fn(
357 move |f| {
358 if f.alternate() { f.write_str(&expr) } else { write!(f, "{}", Escape(&expr)) }
359 },
360 )
361 }
362 }
363
364 impl clean::PolyTrait {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>365 fn print<'a, 'tcx: 'a>(
366 &'a self,
367 cx: &'a Context<'tcx>,
368 ) -> impl fmt::Display + 'a + Captures<'tcx> {
369 display_fn(move |f| {
370 if !self.generic_params.is_empty() {
371 if f.alternate() {
372 write!(
373 f,
374 "for<{:#}> ",
375 comma_sep(self.generic_params.iter().map(|g| g.print(cx)))
376 )?;
377 } else {
378 write!(
379 f,
380 "for<{}> ",
381 comma_sep(self.generic_params.iter().map(|g| g.print(cx)))
382 )?;
383 }
384 }
385 if f.alternate() {
386 write!(f, "{:#}", self.trait_.print(cx))
387 } else {
388 write!(f, "{}", self.trait_.print(cx))
389 }
390 })
391 }
392 }
393
394 impl clean::GenericBound {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>395 crate fn print<'a, 'tcx: 'a>(
396 &'a self,
397 cx: &'a Context<'tcx>,
398 ) -> impl fmt::Display + 'a + Captures<'tcx> {
399 display_fn(move |f| match self {
400 clean::GenericBound::Outlives(lt) => write!(f, "{}", lt.print()),
401 clean::GenericBound::TraitBound(ty, modifier) => {
402 let modifier_str = match modifier {
403 hir::TraitBoundModifier::None => "",
404 hir::TraitBoundModifier::Maybe => "?",
405 hir::TraitBoundModifier::MaybeConst => "~const",
406 };
407 if f.alternate() {
408 write!(f, "{}{:#}", modifier_str, ty.print(cx))
409 } else {
410 write!(f, "{}{}", modifier_str, ty.print(cx))
411 }
412 }
413 })
414 }
415 }
416
417 impl clean::GenericArgs {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>418 fn print<'a, 'tcx: 'a>(
419 &'a self,
420 cx: &'a Context<'tcx>,
421 ) -> impl fmt::Display + 'a + Captures<'tcx> {
422 display_fn(move |f| {
423 match self {
424 clean::GenericArgs::AngleBracketed { args, bindings } => {
425 if !args.is_empty() || !bindings.is_empty() {
426 if f.alternate() {
427 f.write_str("<")?;
428 } else {
429 f.write_str("<")?;
430 }
431 let mut comma = false;
432 for arg in args {
433 if comma {
434 f.write_str(", ")?;
435 }
436 comma = true;
437 if f.alternate() {
438 write!(f, "{:#}", arg.print(cx))?;
439 } else {
440 write!(f, "{}", arg.print(cx))?;
441 }
442 }
443 for binding in bindings {
444 if comma {
445 f.write_str(", ")?;
446 }
447 comma = true;
448 if f.alternate() {
449 write!(f, "{:#}", binding.print(cx))?;
450 } else {
451 write!(f, "{}", binding.print(cx))?;
452 }
453 }
454 if f.alternate() {
455 f.write_str(">")?;
456 } else {
457 f.write_str(">")?;
458 }
459 }
460 }
461 clean::GenericArgs::Parenthesized { inputs, output } => {
462 f.write_str("(")?;
463 let mut comma = false;
464 for ty in inputs {
465 if comma {
466 f.write_str(", ")?;
467 }
468 comma = true;
469 if f.alternate() {
470 write!(f, "{:#}", ty.print(cx))?;
471 } else {
472 write!(f, "{}", ty.print(cx))?;
473 }
474 }
475 f.write_str(")")?;
476 if let Some(ref ty) = *output {
477 if f.alternate() {
478 write!(f, " -> {:#}", ty.print(cx))?;
479 } else {
480 write!(f, " -> {}", ty.print(cx))?;
481 }
482 }
483 }
484 }
485 Ok(())
486 })
487 }
488 }
489
490 // Possible errors when computing href link source for a `DefId`
491 crate enum HrefError {
492 /// This item is known to rustdoc, but from a crate that does not have documentation generated.
493 ///
494 /// This can only happen for non-local items.
495 DocumentationNotBuilt,
496 /// This can only happen for non-local items when `--document-private-items` is not passed.
497 Private,
498 // Not in external cache, href link should be in same page
499 NotInExternalCache,
500 }
501
href_with_root_path( did: DefId, cx: &Context<'_>, root_path: Option<&str>, ) -> Result<(String, ItemType, Vec<String>), HrefError>502 crate fn href_with_root_path(
503 did: DefId,
504 cx: &Context<'_>,
505 root_path: Option<&str>,
506 ) -> Result<(String, ItemType, Vec<String>), HrefError> {
507 let tcx = cx.tcx();
508 let def_kind = tcx.def_kind(did);
509 let did = match def_kind {
510 DefKind::AssocTy | DefKind::AssocFn | DefKind::AssocConst | DefKind::Variant => {
511 // documented on their parent's page
512 tcx.parent(did).unwrap()
513 }
514 _ => did,
515 };
516 let cache = cx.cache();
517 let relative_to = &cx.current;
518 fn to_module_fqp(shortty: ItemType, fqp: &[String]) -> &[String] {
519 if shortty == ItemType::Module { fqp } else { &fqp[..fqp.len() - 1] }
520 }
521
522 if !did.is_local()
523 && !cache.access_levels.is_public(did)
524 && !cache.document_private
525 && !cache.primitive_locations.values().any(|&id| id == did)
526 {
527 return Err(HrefError::Private);
528 }
529
530 let mut is_remote = false;
531 let (fqp, shortty, mut url_parts) = match cache.paths.get(&did) {
532 Some(&(ref fqp, shortty)) => (fqp, shortty, {
533 let module_fqp = to_module_fqp(shortty, fqp);
534 debug!(?fqp, ?shortty, ?module_fqp);
535 href_relative_parts(module_fqp, relative_to)
536 }),
537 None => {
538 if let Some(&(ref fqp, shortty)) = cache.external_paths.get(&did) {
539 let module_fqp = to_module_fqp(shortty, fqp);
540 (
541 fqp,
542 shortty,
543 match cache.extern_locations[&did.krate] {
544 ExternalLocation::Remote(ref s) => {
545 is_remote = true;
546 let s = s.trim_end_matches('/');
547 let mut s = vec![s];
548 s.extend(module_fqp[..].iter().map(String::as_str));
549 s
550 }
551 ExternalLocation::Local => href_relative_parts(module_fqp, relative_to),
552 ExternalLocation::Unknown => return Err(HrefError::DocumentationNotBuilt),
553 },
554 )
555 } else {
556 return Err(HrefError::NotInExternalCache);
557 }
558 }
559 };
560 if !is_remote {
561 if let Some(root_path) = root_path {
562 let root = root_path.trim_end_matches('/');
563 url_parts.insert(0, root);
564 }
565 }
566 debug!(?url_parts);
567 let last = &fqp.last().unwrap()[..];
568 let filename;
569 match shortty {
570 ItemType::Module => {
571 url_parts.push("index.html");
572 }
573 _ => {
574 filename = format!("{}.{}.html", shortty.as_str(), last);
575 url_parts.push(&filename);
576 }
577 }
578 Ok((url_parts.join("/"), shortty, fqp.to_vec()))
579 }
580
href(did: DefId, cx: &Context<'_>) -> Result<(String, ItemType, Vec<String>), HrefError>581 crate fn href(did: DefId, cx: &Context<'_>) -> Result<(String, ItemType, Vec<String>), HrefError> {
582 href_with_root_path(did, cx, None)
583 }
584
585 /// Both paths should only be modules.
586 /// This is because modules get their own directories; that is, `std::vec` and `std::vec::Vec` will
587 /// both need `../iter/trait.Iterator.html` to get at the iterator trait.
href_relative_parts<'a>(fqp: &'a [String], relative_to_fqp: &'a [String]) -> Vec<&'a str>588 crate fn href_relative_parts<'a>(fqp: &'a [String], relative_to_fqp: &'a [String]) -> Vec<&'a str> {
589 for (i, (f, r)) in fqp.iter().zip(relative_to_fqp.iter()).enumerate() {
590 // e.g. linking to std::iter from std::vec (`dissimilar_part_count` will be 1)
591 if f != r {
592 let dissimilar_part_count = relative_to_fqp.len() - i;
593 let fqp_module = fqp[i..fqp.len()].iter().map(String::as_str);
594 return iter::repeat("..").take(dissimilar_part_count).chain(fqp_module).collect();
595 }
596 }
597 // e.g. linking to std::sync::atomic from std::sync
598 if relative_to_fqp.len() < fqp.len() {
599 fqp[relative_to_fqp.len()..fqp.len()].iter().map(String::as_str).collect()
600 // e.g. linking to std::sync from std::sync::atomic
601 } else if fqp.len() < relative_to_fqp.len() {
602 let dissimilar_part_count = relative_to_fqp.len() - fqp.len();
603 iter::repeat("..").take(dissimilar_part_count).collect()
604 // linking to the same module
605 } else {
606 Vec::new()
607 }
608 }
609
610 /// Used to render a [`clean::Path`].
resolved_path<'cx>( w: &mut fmt::Formatter<'_>, did: DefId, path: &clean::Path, print_all: bool, use_absolute: bool, cx: &'cx Context<'_>, ) -> fmt::Result611 fn resolved_path<'cx>(
612 w: &mut fmt::Formatter<'_>,
613 did: DefId,
614 path: &clean::Path,
615 print_all: bool,
616 use_absolute: bool,
617 cx: &'cx Context<'_>,
618 ) -> fmt::Result {
619 let last = path.segments.last().unwrap();
620
621 if print_all {
622 for seg in &path.segments[..path.segments.len() - 1] {
623 write!(w, "{}::", seg.name)?;
624 }
625 }
626 if w.alternate() {
627 write!(w, "{}{:#}", &last.name, last.args.print(cx))?;
628 } else {
629 let path = if use_absolute {
630 if let Ok((_, _, fqp)) = href(did, cx) {
631 format!(
632 "{}::{}",
633 fqp[..fqp.len() - 1].join("::"),
634 anchor(did, fqp.last().unwrap(), cx)
635 )
636 } else {
637 last.name.to_string()
638 }
639 } else {
640 anchor(did, &*last.name.as_str(), cx).to_string()
641 };
642 write!(w, "{}{}", path, last.args.print(cx))?;
643 }
644 Ok(())
645 }
646
primitive_link( f: &mut fmt::Formatter<'_>, prim: clean::PrimitiveType, name: &str, cx: &Context<'_>, ) -> fmt::Result647 fn primitive_link(
648 f: &mut fmt::Formatter<'_>,
649 prim: clean::PrimitiveType,
650 name: &str,
651 cx: &Context<'_>,
652 ) -> fmt::Result {
653 let m = &cx.cache();
654 let mut needs_termination = false;
655 if !f.alternate() {
656 match m.primitive_locations.get(&prim) {
657 Some(&def_id) if def_id.is_local() => {
658 let len = cx.current.len();
659 let len = if len == 0 { 0 } else { len - 1 };
660 write!(
661 f,
662 "<a class=\"primitive\" href=\"{}primitive.{}.html\">",
663 "../".repeat(len),
664 prim.as_sym()
665 )?;
666 needs_termination = true;
667 }
668 Some(&def_id) => {
669 let cname_str;
670 let loc = match m.extern_locations[&def_id.krate] {
671 ExternalLocation::Remote(ref s) => {
672 cname_str =
673 ExternalCrate { crate_num: def_id.krate }.name(cx.tcx()).as_str();
674 Some(vec![s.trim_end_matches('/'), &cname_str[..]])
675 }
676 ExternalLocation::Local => {
677 cname_str =
678 ExternalCrate { crate_num: def_id.krate }.name(cx.tcx()).as_str();
679 Some(if cx.current.first().map(|x| &x[..]) == Some(&cname_str[..]) {
680 iter::repeat("..").take(cx.current.len() - 1).collect()
681 } else {
682 let cname = iter::once(&cname_str[..]);
683 iter::repeat("..").take(cx.current.len()).chain(cname).collect()
684 })
685 }
686 ExternalLocation::Unknown => None,
687 };
688 if let Some(loc) = loc {
689 write!(
690 f,
691 "<a class=\"primitive\" href=\"{}/primitive.{}.html\">",
692 loc.join("/"),
693 prim.as_sym()
694 )?;
695 needs_termination = true;
696 }
697 }
698 None => {}
699 }
700 }
701 write!(f, "{}", name)?;
702 if needs_termination {
703 write!(f, "</a>")?;
704 }
705 Ok(())
706 }
707
708 /// Helper to render type parameters
tybounds<'a, 'tcx: 'a>( bounds: &'a [clean::PolyTrait], lt: &'a Option<clean::Lifetime>, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>709 fn tybounds<'a, 'tcx: 'a>(
710 bounds: &'a [clean::PolyTrait],
711 lt: &'a Option<clean::Lifetime>,
712 cx: &'a Context<'tcx>,
713 ) -> impl fmt::Display + 'a + Captures<'tcx> {
714 display_fn(move |f| {
715 for (i, bound) in bounds.iter().enumerate() {
716 if i > 0 {
717 write!(f, " + ")?;
718 }
719
720 fmt::Display::fmt(&bound.print(cx), f)?;
721 }
722
723 if let Some(lt) = lt {
724 write!(f, " + ")?;
725 fmt::Display::fmt(<.print(), f)?;
726 }
727 Ok(())
728 })
729 }
730
anchor<'a, 'cx: 'a>( did: DefId, text: &'a str, cx: &'cx Context<'_>, ) -> impl fmt::Display + 'a731 crate fn anchor<'a, 'cx: 'a>(
732 did: DefId,
733 text: &'a str,
734 cx: &'cx Context<'_>,
735 ) -> impl fmt::Display + 'a {
736 let parts = href(did, cx);
737 display_fn(move |f| {
738 if let Ok((url, short_ty, fqp)) = parts {
739 write!(
740 f,
741 r#"<a class="{}" href="{}" title="{} {}">{}</a>"#,
742 short_ty,
743 url,
744 short_ty,
745 fqp.join("::"),
746 text
747 )
748 } else {
749 write!(f, "{}", text)
750 }
751 })
752 }
753
fmt_type<'cx>( t: &clean::Type, f: &mut fmt::Formatter<'_>, use_absolute: bool, cx: &'cx Context<'_>, ) -> fmt::Result754 fn fmt_type<'cx>(
755 t: &clean::Type,
756 f: &mut fmt::Formatter<'_>,
757 use_absolute: bool,
758 cx: &'cx Context<'_>,
759 ) -> fmt::Result {
760 trace!("fmt_type(t = {:?})", t);
761
762 match *t {
763 clean::Generic(name) => write!(f, "{}", name),
764 clean::Type::Path { ref path } => {
765 // Paths like `T::Output` and `Self::Output` should be rendered with all segments.
766 let did = path.def_id();
767 resolved_path(f, did, path, path.is_assoc_ty(), use_absolute, cx)
768 }
769 clean::DynTrait(ref bounds, ref lt) => {
770 f.write_str("dyn ")?;
771 fmt::Display::fmt(&tybounds(bounds, lt, cx), f)
772 }
773 clean::Infer => write!(f, "_"),
774 clean::Primitive(clean::PrimitiveType::Never) => {
775 primitive_link(f, PrimitiveType::Never, "!", cx)
776 }
777 clean::Primitive(prim) => primitive_link(f, prim, &*prim.as_sym().as_str(), cx),
778 clean::BareFunction(ref decl) => {
779 if f.alternate() {
780 write!(
781 f,
782 "{:#}{}{:#}fn{:#}",
783 decl.print_hrtb_with_space(cx),
784 decl.unsafety.print_with_space(),
785 print_abi_with_space(decl.abi),
786 decl.decl.print(cx),
787 )
788 } else {
789 write!(
790 f,
791 "{}{}{}",
792 decl.print_hrtb_with_space(cx),
793 decl.unsafety.print_with_space(),
794 print_abi_with_space(decl.abi)
795 )?;
796 primitive_link(f, PrimitiveType::Fn, "fn", cx)?;
797 write!(f, "{}", decl.decl.print(cx))
798 }
799 }
800 clean::Tuple(ref typs) => {
801 match &typs[..] {
802 &[] => primitive_link(f, PrimitiveType::Unit, "()", cx),
803 &[ref one] => {
804 primitive_link(f, PrimitiveType::Tuple, "(", cx)?;
805 // Carry `f.alternate()` into this display w/o branching manually.
806 fmt::Display::fmt(&one.print(cx), f)?;
807 primitive_link(f, PrimitiveType::Tuple, ",)", cx)
808 }
809 many => {
810 primitive_link(f, PrimitiveType::Tuple, "(", cx)?;
811 for (i, item) in many.iter().enumerate() {
812 if i != 0 {
813 write!(f, ", ")?;
814 }
815 fmt::Display::fmt(&item.print(cx), f)?;
816 }
817 primitive_link(f, PrimitiveType::Tuple, ")", cx)
818 }
819 }
820 }
821 clean::Slice(ref t) => {
822 primitive_link(f, PrimitiveType::Slice, "[", cx)?;
823 fmt::Display::fmt(&t.print(cx), f)?;
824 primitive_link(f, PrimitiveType::Slice, "]", cx)
825 }
826 clean::Array(ref t, ref n) => {
827 primitive_link(f, PrimitiveType::Array, "[", cx)?;
828 fmt::Display::fmt(&t.print(cx), f)?;
829 if f.alternate() {
830 primitive_link(f, PrimitiveType::Array, &format!("; {}]", n), cx)
831 } else {
832 primitive_link(f, PrimitiveType::Array, &format!("; {}]", Escape(n)), cx)
833 }
834 }
835 clean::RawPointer(m, ref t) => {
836 let m = match m {
837 hir::Mutability::Mut => "mut",
838 hir::Mutability::Not => "const",
839 };
840
841 if matches!(**t, clean::Generic(_)) || t.is_assoc_ty() {
842 let text = if f.alternate() {
843 format!("*{} {:#}", m, t.print(cx))
844 } else {
845 format!("*{} {}", m, t.print(cx))
846 };
847 primitive_link(f, clean::PrimitiveType::RawPointer, &text, cx)
848 } else {
849 primitive_link(f, clean::PrimitiveType::RawPointer, &format!("*{} ", m), cx)?;
850 fmt::Display::fmt(&t.print(cx), f)
851 }
852 }
853 clean::BorrowedRef { lifetime: ref l, mutability, type_: ref ty } => {
854 let lt = match l {
855 Some(l) => format!("{} ", l.print()),
856 _ => String::new(),
857 };
858 let m = mutability.print_with_space();
859 let amp = if f.alternate() { "&".to_string() } else { "&".to_string() };
860 match **ty {
861 clean::Slice(ref bt) => {
862 // `BorrowedRef{ ... Slice(T) }` is `&[T]`
863 match **bt {
864 clean::Generic(_) => {
865 if f.alternate() {
866 primitive_link(
867 f,
868 PrimitiveType::Slice,
869 &format!("{}{}{}[{:#}]", amp, lt, m, bt.print(cx)),
870 cx,
871 )
872 } else {
873 primitive_link(
874 f,
875 PrimitiveType::Slice,
876 &format!("{}{}{}[{}]", amp, lt, m, bt.print(cx)),
877 cx,
878 )
879 }
880 }
881 _ => {
882 primitive_link(
883 f,
884 PrimitiveType::Slice,
885 &format!("{}{}{}[", amp, lt, m),
886 cx,
887 )?;
888 if f.alternate() {
889 write!(f, "{:#}", bt.print(cx))?;
890 } else {
891 write!(f, "{}", bt.print(cx))?;
892 }
893 primitive_link(f, PrimitiveType::Slice, "]", cx)
894 }
895 }
896 }
897 clean::DynTrait(ref bounds, ref trait_lt)
898 if bounds.len() > 1 || trait_lt.is_some() =>
899 {
900 write!(f, "{}{}{}(", amp, lt, m)?;
901 fmt_type(ty, f, use_absolute, cx)?;
902 write!(f, ")")
903 }
904 clean::Generic(..) => {
905 primitive_link(
906 f,
907 PrimitiveType::Reference,
908 &format!("{}{}{}", amp, lt, m),
909 cx,
910 )?;
911 fmt_type(ty, f, use_absolute, cx)
912 }
913 _ => {
914 write!(f, "{}{}{}", amp, lt, m)?;
915 fmt_type(ty, f, use_absolute, cx)
916 }
917 }
918 }
919 clean::ImplTrait(ref bounds) => {
920 if f.alternate() {
921 write!(f, "impl {:#}", print_generic_bounds(bounds, cx))
922 } else {
923 write!(f, "impl {}", print_generic_bounds(bounds, cx))
924 }
925 }
926 clean::QPath { ref name, ref self_type, ref trait_, ref self_def_id } => {
927 let should_show_cast = !trait_.segments.is_empty()
928 && self_def_id
929 .zip(Some(trait_.def_id()))
930 .map_or(!self_type.is_self_type(), |(id, trait_)| id != trait_);
931 if f.alternate() {
932 if should_show_cast {
933 write!(f, "<{:#} as {:#}>::", self_type.print(cx), trait_.print(cx))?
934 } else {
935 write!(f, "{:#}::", self_type.print(cx))?
936 }
937 } else {
938 if should_show_cast {
939 write!(f, "<{} as {}>::", self_type.print(cx), trait_.print(cx))?
940 } else {
941 write!(f, "{}::", self_type.print(cx))?
942 }
943 };
944 // It's pretty unsightly to look at `<A as B>::C` in output, and
945 // we've got hyperlinking on our side, so try to avoid longer
946 // notation as much as possible by making `C` a hyperlink to trait
947 // `B` to disambiguate.
948 //
949 // FIXME: this is still a lossy conversion and there should probably
950 // be a better way of representing this in general? Most of
951 // the ugliness comes from inlining across crates where
952 // everything comes in as a fully resolved QPath (hard to
953 // look at).
954 match href(trait_.def_id(), cx) {
955 Ok((ref url, _, ref path)) if !f.alternate() => {
956 write!(
957 f,
958 "<a class=\"type\" href=\"{url}#{shortty}.{name}\" \
959 title=\"type {path}::{name}\">{name}</a>",
960 url = url,
961 shortty = ItemType::AssocType,
962 name = name,
963 path = path.join("::")
964 )?;
965 }
966 _ => write!(f, "{}", name)?,
967 }
968 Ok(())
969 }
970 }
971 }
972
973 impl clean::Type {
print<'b, 'a: 'b, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'b + Captures<'tcx>974 crate fn print<'b, 'a: 'b, 'tcx: 'a>(
975 &'a self,
976 cx: &'a Context<'tcx>,
977 ) -> impl fmt::Display + 'b + Captures<'tcx> {
978 display_fn(move |f| fmt_type(self, f, false, cx))
979 }
980 }
981
982 impl clean::Path {
print<'b, 'a: 'b, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'b + Captures<'tcx>983 crate fn print<'b, 'a: 'b, 'tcx: 'a>(
984 &'a self,
985 cx: &'a Context<'tcx>,
986 ) -> impl fmt::Display + 'b + Captures<'tcx> {
987 display_fn(move |f| resolved_path(f, self.def_id(), self, false, false, cx))
988 }
989 }
990
991 impl clean::Impl {
print<'a, 'tcx: 'a>( &'a self, use_absolute: bool, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>992 crate fn print<'a, 'tcx: 'a>(
993 &'a self,
994 use_absolute: bool,
995 cx: &'a Context<'tcx>,
996 ) -> impl fmt::Display + 'a + Captures<'tcx> {
997 display_fn(move |f| {
998 if f.alternate() {
999 write!(f, "impl{:#} ", self.generics.print(cx))?;
1000 } else {
1001 write!(f, "impl{} ", self.generics.print(cx))?;
1002 }
1003
1004 if let Some(ref ty) = self.trait_ {
1005 match self.polarity {
1006 ty::ImplPolarity::Positive | ty::ImplPolarity::Reservation => {}
1007 ty::ImplPolarity::Negative => write!(f, "!")?,
1008 }
1009 fmt::Display::fmt(&ty.print(cx), f)?;
1010 write!(f, " for ")?;
1011 }
1012
1013 if let Some(ref ty) = self.kind.as_blanket_ty() {
1014 fmt_type(ty, f, use_absolute, cx)?;
1015 } else {
1016 fmt_type(&self.for_, f, use_absolute, cx)?;
1017 }
1018
1019 fmt::Display::fmt(&print_where_clause(&self.generics, cx, 0, true), f)?;
1020 Ok(())
1021 })
1022 }
1023 }
1024
1025 impl clean::Arguments {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>1026 crate fn print<'a, 'tcx: 'a>(
1027 &'a self,
1028 cx: &'a Context<'tcx>,
1029 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1030 display_fn(move |f| {
1031 for (i, input) in self.values.iter().enumerate() {
1032 if !input.name.is_empty() {
1033 write!(f, "{}: ", input.name)?;
1034 }
1035 if f.alternate() {
1036 write!(f, "{:#}", input.type_.print(cx))?;
1037 } else {
1038 write!(f, "{}", input.type_.print(cx))?;
1039 }
1040 if i + 1 < self.values.len() {
1041 write!(f, ", ")?;
1042 }
1043 }
1044 Ok(())
1045 })
1046 }
1047 }
1048
1049 impl clean::FnRetTy {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>1050 crate fn print<'a, 'tcx: 'a>(
1051 &'a self,
1052 cx: &'a Context<'tcx>,
1053 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1054 display_fn(move |f| match self {
1055 clean::Return(clean::Tuple(tys)) if tys.is_empty() => Ok(()),
1056 clean::Return(ty) if f.alternate() => {
1057 write!(f, " -> {:#}", ty.print(cx))
1058 }
1059 clean::Return(ty) => write!(f, " -> {}", ty.print(cx)),
1060 clean::DefaultReturn => Ok(()),
1061 })
1062 }
1063 }
1064
1065 impl clean::BareFunctionDecl {
print_hrtb_with_space<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>1066 fn print_hrtb_with_space<'a, 'tcx: 'a>(
1067 &'a self,
1068 cx: &'a Context<'tcx>,
1069 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1070 display_fn(move |f| {
1071 if !self.generic_params.is_empty() {
1072 write!(
1073 f,
1074 "for<{}> ",
1075 comma_sep(self.generic_params.iter().map(|g| g.print(cx)))
1076 )
1077 } else {
1078 Ok(())
1079 }
1080 })
1081 }
1082 }
1083
1084 impl clean::FnDecl {
print<'b, 'a: 'b, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'b + Captures<'tcx>1085 crate fn print<'b, 'a: 'b, 'tcx: 'a>(
1086 &'a self,
1087 cx: &'a Context<'tcx>,
1088 ) -> impl fmt::Display + 'b + Captures<'tcx> {
1089 display_fn(move |f| {
1090 let ellipsis = if self.c_variadic { ", ..." } else { "" };
1091 if f.alternate() {
1092 write!(
1093 f,
1094 "({args:#}{ellipsis}){arrow:#}",
1095 args = self.inputs.print(cx),
1096 ellipsis = ellipsis,
1097 arrow = self.output.print(cx)
1098 )
1099 } else {
1100 write!(
1101 f,
1102 "({args}{ellipsis}){arrow}",
1103 args = self.inputs.print(cx),
1104 ellipsis = ellipsis,
1105 arrow = self.output.print(cx)
1106 )
1107 }
1108 })
1109 }
1110
1111 /// * `header_len`: The length of the function header and name. In other words, the number of
1112 /// characters in the function declaration up to but not including the parentheses.
1113 /// <br>Used to determine line-wrapping.
1114 /// * `indent`: The number of spaces to indent each successive line with, if line-wrapping is
1115 /// necessary.
1116 /// * `asyncness`: Whether the function is async or not.
full_print<'a, 'tcx: 'a>( &'a self, header_len: usize, indent: usize, asyncness: hir::IsAsync, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>1117 crate fn full_print<'a, 'tcx: 'a>(
1118 &'a self,
1119 header_len: usize,
1120 indent: usize,
1121 asyncness: hir::IsAsync,
1122 cx: &'a Context<'tcx>,
1123 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1124 display_fn(move |f| self.inner_full_print(header_len, indent, asyncness, f, cx))
1125 }
1126
inner_full_print( &self, header_len: usize, indent: usize, asyncness: hir::IsAsync, f: &mut fmt::Formatter<'_>, cx: &Context<'_>, ) -> fmt::Result1127 fn inner_full_print(
1128 &self,
1129 header_len: usize,
1130 indent: usize,
1131 asyncness: hir::IsAsync,
1132 f: &mut fmt::Formatter<'_>,
1133 cx: &Context<'_>,
1134 ) -> fmt::Result {
1135 let amp = if f.alternate() { "&" } else { "&" };
1136 let mut args = String::new();
1137 let mut args_plain = String::new();
1138 for (i, input) in self.inputs.values.iter().enumerate() {
1139 if i == 0 {
1140 args.push_str("<br>");
1141 }
1142
1143 if let Some(selfty) = input.to_self() {
1144 match selfty {
1145 clean::SelfValue => {
1146 args.push_str("self");
1147 args_plain.push_str("self");
1148 }
1149 clean::SelfBorrowed(Some(ref lt), mtbl) => {
1150 args.push_str(&format!(
1151 "{}{} {}self",
1152 amp,
1153 lt.print(),
1154 mtbl.print_with_space()
1155 ));
1156 args_plain.push_str(&format!(
1157 "&{} {}self",
1158 lt.print(),
1159 mtbl.print_with_space()
1160 ));
1161 }
1162 clean::SelfBorrowed(None, mtbl) => {
1163 args.push_str(&format!("{}{}self", amp, mtbl.print_with_space()));
1164 args_plain.push_str(&format!("&{}self", mtbl.print_with_space()));
1165 }
1166 clean::SelfExplicit(ref typ) => {
1167 if f.alternate() {
1168 args.push_str(&format!("self: {:#}", typ.print(cx)));
1169 } else {
1170 args.push_str(&format!("self: {}", typ.print(cx)));
1171 }
1172 args_plain.push_str(&format!("self: {:#}", typ.print(cx)));
1173 }
1174 }
1175 } else {
1176 if i > 0 {
1177 args.push_str(" <br>");
1178 args_plain.push(' ');
1179 }
1180 if !input.name.is_empty() {
1181 args.push_str(&format!("{}: ", input.name));
1182 args_plain.push_str(&format!("{}: ", input.name));
1183 }
1184
1185 if f.alternate() {
1186 args.push_str(&format!("{:#}", input.type_.print(cx)));
1187 } else {
1188 args.push_str(&input.type_.print(cx).to_string());
1189 }
1190 args_plain.push_str(&format!("{:#}", input.type_.print(cx)));
1191 }
1192 if i + 1 < self.inputs.values.len() {
1193 args.push(',');
1194 args_plain.push(',');
1195 }
1196 }
1197
1198 let mut args_plain = format!("({})", args_plain);
1199
1200 if self.c_variadic {
1201 args.push_str(",<br> ...");
1202 args_plain.push_str(", ...");
1203 }
1204
1205 let arrow_plain;
1206 let arrow = if let hir::IsAsync::Async = asyncness {
1207 let output = self.sugared_async_return_type();
1208 arrow_plain = format!("{:#}", output.print(cx));
1209 if f.alternate() { arrow_plain.clone() } else { format!("{}", output.print(cx)) }
1210 } else {
1211 arrow_plain = format!("{:#}", self.output.print(cx));
1212 if f.alternate() { arrow_plain.clone() } else { format!("{}", self.output.print(cx)) }
1213 };
1214
1215 let declaration_len = header_len + args_plain.len() + arrow_plain.len();
1216 let output = if declaration_len > 80 {
1217 let full_pad = format!("<br>{}", " ".repeat(indent + 4));
1218 let close_pad = format!("<br>{}", " ".repeat(indent));
1219 format!(
1220 "({args}{close}){arrow}",
1221 args = args.replace("<br>", &full_pad),
1222 close = close_pad,
1223 arrow = arrow
1224 )
1225 } else {
1226 format!("({args}){arrow}", args = args.replace("<br>", ""), arrow = arrow)
1227 };
1228
1229 if f.alternate() {
1230 write!(f, "{}", output.replace("<br>", "\n"))
1231 } else {
1232 write!(f, "{}", output)
1233 }
1234 }
1235 }
1236
1237 impl clean::Visibility {
print_with_space<'a, 'tcx: 'a>( self, item_did: ItemId, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>1238 crate fn print_with_space<'a, 'tcx: 'a>(
1239 self,
1240 item_did: ItemId,
1241 cx: &'a Context<'tcx>,
1242 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1243 let to_print = match self {
1244 clean::Public => "pub ".to_owned(),
1245 clean::Inherited => String::new(),
1246 clean::Visibility::Restricted(vis_did) => {
1247 // FIXME(camelid): This may not work correctly if `item_did` is a module.
1248 // However, rustdoc currently never displays a module's
1249 // visibility, so it shouldn't matter.
1250 let parent_module = find_nearest_parent_module(cx.tcx(), item_did.expect_def_id());
1251
1252 if vis_did.index == CRATE_DEF_INDEX {
1253 "pub(crate) ".to_owned()
1254 } else if parent_module == Some(vis_did) {
1255 // `pub(in foo)` where `foo` is the parent module
1256 // is the same as no visibility modifier
1257 String::new()
1258 } else if parent_module
1259 .map(|parent| find_nearest_parent_module(cx.tcx(), parent))
1260 .flatten()
1261 == Some(vis_did)
1262 {
1263 "pub(super) ".to_owned()
1264 } else {
1265 let path = cx.tcx().def_path(vis_did);
1266 debug!("path={:?}", path);
1267 // modified from `resolved_path()` to work with `DefPathData`
1268 let last_name = path.data.last().unwrap().data.get_opt_name().unwrap();
1269 let anchor = anchor(vis_did, &last_name.as_str(), cx).to_string();
1270
1271 let mut s = "pub(in ".to_owned();
1272 for seg in &path.data[..path.data.len() - 1] {
1273 s.push_str(&format!("{}::", seg.data.get_opt_name().unwrap()));
1274 }
1275 s.push_str(&format!("{}) ", anchor));
1276 s
1277 }
1278 }
1279 };
1280 display_fn(move |f| f.write_str(&to_print))
1281 }
1282
1283 /// This function is the same as print_with_space, except that it renders no links.
1284 /// It's used for macros' rendered source view, which is syntax highlighted and cannot have
1285 /// any HTML in it.
to_src_with_space<'a, 'tcx: 'a>( self, tcx: TyCtxt<'tcx>, item_did: DefId, ) -> impl fmt::Display + 'a + Captures<'tcx>1286 crate fn to_src_with_space<'a, 'tcx: 'a>(
1287 self,
1288 tcx: TyCtxt<'tcx>,
1289 item_did: DefId,
1290 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1291 let to_print = match self {
1292 clean::Public => "pub ".to_owned(),
1293 clean::Inherited => String::new(),
1294 clean::Visibility::Restricted(vis_did) => {
1295 // FIXME(camelid): This may not work correctly if `item_did` is a module.
1296 // However, rustdoc currently never displays a module's
1297 // visibility, so it shouldn't matter.
1298 let parent_module = find_nearest_parent_module(tcx, item_did);
1299
1300 if vis_did.index == CRATE_DEF_INDEX {
1301 "pub(crate) ".to_owned()
1302 } else if parent_module == Some(vis_did) {
1303 // `pub(in foo)` where `foo` is the parent module
1304 // is the same as no visibility modifier
1305 String::new()
1306 } else if parent_module
1307 .map(|parent| find_nearest_parent_module(tcx, parent))
1308 .flatten()
1309 == Some(vis_did)
1310 {
1311 "pub(super) ".to_owned()
1312 } else {
1313 format!("pub(in {}) ", tcx.def_path_str(vis_did))
1314 }
1315 }
1316 };
1317 display_fn(move |f| f.write_str(&to_print))
1318 }
1319 }
1320
1321 crate trait PrintWithSpace {
print_with_space(&self) -> &str1322 fn print_with_space(&self) -> &str;
1323 }
1324
1325 impl PrintWithSpace for hir::Unsafety {
print_with_space(&self) -> &str1326 fn print_with_space(&self) -> &str {
1327 match self {
1328 hir::Unsafety::Unsafe => "unsafe ",
1329 hir::Unsafety::Normal => "",
1330 }
1331 }
1332 }
1333
1334 impl PrintWithSpace for hir::IsAsync {
print_with_space(&self) -> &str1335 fn print_with_space(&self) -> &str {
1336 match self {
1337 hir::IsAsync::Async => "async ",
1338 hir::IsAsync::NotAsync => "",
1339 }
1340 }
1341 }
1342
1343 impl PrintWithSpace for hir::Mutability {
print_with_space(&self) -> &str1344 fn print_with_space(&self) -> &str {
1345 match self {
1346 hir::Mutability::Not => "",
1347 hir::Mutability::Mut => "mut ",
1348 }
1349 }
1350 }
1351
print_constness_with_space( c: &hir::Constness, s: Option<&ConstStability>, ) -> &'static str1352 crate fn print_constness_with_space(
1353 c: &hir::Constness,
1354 s: Option<&ConstStability>,
1355 ) -> &'static str {
1356 match (c, s) {
1357 // const stable or when feature(staged_api) is not set
1358 (
1359 hir::Constness::Const,
1360 Some(ConstStability { level: StabilityLevel::Stable { .. }, .. }),
1361 )
1362 | (hir::Constness::Const, None) => "const ",
1363 // const unstable or not const
1364 _ => "",
1365 }
1366 }
1367
1368 impl clean::Import {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>1369 crate fn print<'a, 'tcx: 'a>(
1370 &'a self,
1371 cx: &'a Context<'tcx>,
1372 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1373 display_fn(move |f| match self.kind {
1374 clean::ImportKind::Simple(name) => {
1375 if name == self.source.path.last() {
1376 write!(f, "use {};", self.source.print(cx))
1377 } else {
1378 write!(f, "use {} as {};", self.source.print(cx), name)
1379 }
1380 }
1381 clean::ImportKind::Glob => {
1382 if self.source.path.segments.is_empty() {
1383 write!(f, "use *;")
1384 } else {
1385 write!(f, "use {}::*;", self.source.print(cx))
1386 }
1387 }
1388 })
1389 }
1390 }
1391
1392 impl clean::ImportSource {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>1393 crate fn print<'a, 'tcx: 'a>(
1394 &'a self,
1395 cx: &'a Context<'tcx>,
1396 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1397 display_fn(move |f| match self.did {
1398 Some(did) => resolved_path(f, did, &self.path, true, false, cx),
1399 _ => {
1400 for seg in &self.path.segments[..self.path.segments.len() - 1] {
1401 write!(f, "{}::", seg.name)?;
1402 }
1403 let name = self.path.last_name();
1404 if let hir::def::Res::PrimTy(p) = self.path.res {
1405 primitive_link(f, PrimitiveType::from(p), &*name, cx)?;
1406 } else {
1407 write!(f, "{}", name)?;
1408 }
1409 Ok(())
1410 }
1411 })
1412 }
1413 }
1414
1415 impl clean::TypeBinding {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>1416 crate fn print<'a, 'tcx: 'a>(
1417 &'a self,
1418 cx: &'a Context<'tcx>,
1419 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1420 display_fn(move |f| {
1421 f.write_str(&*self.name.as_str())?;
1422 match self.kind {
1423 clean::TypeBindingKind::Equality { ref ty } => {
1424 if f.alternate() {
1425 write!(f, " = {:#}", ty.print(cx))?;
1426 } else {
1427 write!(f, " = {}", ty.print(cx))?;
1428 }
1429 }
1430 clean::TypeBindingKind::Constraint { ref bounds } => {
1431 if !bounds.is_empty() {
1432 if f.alternate() {
1433 write!(f, ": {:#}", print_generic_bounds(bounds, cx))?;
1434 } else {
1435 write!(f, ": {}", print_generic_bounds(bounds, cx))?;
1436 }
1437 }
1438 }
1439 }
1440 Ok(())
1441 })
1442 }
1443 }
1444
print_abi_with_space(abi: Abi) -> impl fmt::Display1445 crate fn print_abi_with_space(abi: Abi) -> impl fmt::Display {
1446 display_fn(move |f| {
1447 let quot = if f.alternate() { "\"" } else { """ };
1448 match abi {
1449 Abi::Rust => Ok(()),
1450 abi => write!(f, "extern {0}{1}{0} ", quot, abi.name()),
1451 }
1452 })
1453 }
1454
print_default_space<'a>(v: bool) -> &'a str1455 crate fn print_default_space<'a>(v: bool) -> &'a str {
1456 if v { "default " } else { "" }
1457 }
1458
1459 impl clean::GenericArg {
print<'a, 'tcx: 'a>( &'a self, cx: &'a Context<'tcx>, ) -> impl fmt::Display + 'a + Captures<'tcx>1460 crate fn print<'a, 'tcx: 'a>(
1461 &'a self,
1462 cx: &'a Context<'tcx>,
1463 ) -> impl fmt::Display + 'a + Captures<'tcx> {
1464 display_fn(move |f| match self {
1465 clean::GenericArg::Lifetime(lt) => fmt::Display::fmt(<.print(), f),
1466 clean::GenericArg::Type(ty) => fmt::Display::fmt(&ty.print(cx), f),
1467 clean::GenericArg::Const(ct) => fmt::Display::fmt(&ct.print(cx.tcx()), f),
1468 clean::GenericArg::Infer => fmt::Display::fmt("_", f),
1469 })
1470 }
1471 }
1472
display_fn(f: impl FnOnce(&mut fmt::Formatter<'_>) -> fmt::Result) -> impl fmt::Display1473 crate fn display_fn(f: impl FnOnce(&mut fmt::Formatter<'_>) -> fmt::Result) -> impl fmt::Display {
1474 struct WithFormatter<F>(Cell<Option<F>>);
1475
1476 impl<F> fmt::Display for WithFormatter<F>
1477 where
1478 F: FnOnce(&mut fmt::Formatter<'_>) -> fmt::Result,
1479 {
1480 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1481 (self.0.take()).unwrap()(f)
1482 }
1483 }
1484
1485 WithFormatter(Cell::new(Some(f)))
1486 }
1487