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rustc_ast_pretty/pprust/state/
item.rs

1use ast::StaticItem;
2use rustc_ast::{self as ast, EiiImpl, ModKind, Safety, TraitAlias};
3use rustc_span::Ident;
4
5use crate::pp::BoxMarker;
6use crate::pp::Breaks::Inconsistent;
7use crate::pprust::state::fixup::FixupContext;
8use crate::pprust::state::{AnnNode, INDENT_UNIT, PrintState, State};
9
10enum DelegationKind<'a> {
11    Single,
12    List(&'a [(Ident, Option<Ident>)]),
13    Glob,
14}
15
16fn visibility_qualified(vis: &ast::Visibility, s: &str) -> String {
17    ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("{0}{1}",
                State::to_string(|s| s.print_visibility(vis)), s))
    })format!("{}{}", State::to_string(|s| s.print_visibility(vis)), s)
18}
19
20impl<'a> State<'a> {
21    fn print_foreign_mod(&mut self, nmod: &ast::ForeignMod, attrs: &[ast::Attribute]) {
22        self.print_inner_attributes(attrs);
23        for item in &nmod.items {
24            self.print_foreign_item(item);
25        }
26    }
27
28    pub(crate) fn print_foreign_item(&mut self, item: &ast::ForeignItem) {
29        let ast::Item { id, span, ref attrs, ref kind, ref vis, tokens: _ } = *item;
30        self.ann.pre(self, AnnNode::SubItem(id));
31        self.hardbreak_if_not_bol();
32        self.maybe_print_comment(span.lo());
33        self.print_outer_attributes(attrs);
34        match kind {
35            ast::ForeignItemKind::Fn(func) => {
36                self.print_fn_full(vis, attrs, &*func);
37            }
38            ast::ForeignItemKind::Static(ast::StaticItem {
39                ident,
40                ty,
41                mutability,
42                expr,
43                safety,
44                define_opaque,
45                eii_impl,
46            }) => self.print_item_const(
47                *ident,
48                Some(*mutability),
49                &ast::Generics::default(),
50                ty,
51                expr.as_deref(),
52                vis,
53                *safety,
54                ast::Defaultness::Implicit,
55                define_opaque.as_deref(),
56                eii_impl.as_deref(),
57            ),
58            ast::ForeignItemKind::TyAlias(ast::TyAlias {
59                defaultness,
60                ident,
61                generics,
62                after_where_clause,
63                bounds,
64                ty,
65            }) => {
66                self.print_associated_type(
67                    *ident,
68                    generics,
69                    after_where_clause,
70                    bounds,
71                    ty.as_deref(),
72                    vis,
73                    *defaultness,
74                );
75            }
76            ast::ForeignItemKind::MacCall(m) => {
77                self.print_mac(m);
78                if m.args.need_semicolon() {
79                    self.word(";");
80                }
81            }
82        }
83        self.ann.post(self, AnnNode::SubItem(id))
84    }
85
86    fn print_item_const(
87        &mut self,
88        ident: Ident,
89        mutbl: Option<ast::Mutability>,
90        generics: &ast::Generics,
91        ty: &ast::Ty,
92        body: Option<&ast::Expr>,
93        vis: &ast::Visibility,
94        safety: ast::Safety,
95        defaultness: ast::Defaultness,
96        define_opaque: Option<&[(ast::NodeId, ast::Path)]>,
97        eii_impl: Option<&EiiImpl>,
98    ) {
99        self.print_define_opaques(define_opaque);
100        if let Some(eii_impl) = eii_impl {
101            self.print_eii_impl(eii_impl);
102        }
103        let (cb, ib) = self.head("");
104        self.print_visibility(vis);
105        self.print_safety(safety);
106        self.print_defaultness(defaultness);
107        let leading = match mutbl {
108            None => "const",
109            Some(ast::Mutability::Not) => "static",
110            Some(ast::Mutability::Mut) => "static mut",
111        };
112        self.word_space(leading);
113        self.print_ident(ident);
114        self.print_generic_params(&generics.params);
115        self.word_space(":");
116        self.print_type(ty);
117        if body.is_some() {
118            self.space();
119        }
120        self.end(ib);
121        if let Some(body) = body {
122            self.word_space("=");
123            self.print_expr(body, FixupContext::default());
124        }
125        self.print_where_clause(&generics.where_clause);
126        self.word(";");
127        self.end(cb);
128    }
129
130    fn print_associated_type(
131        &mut self,
132        ident: Ident,
133        generics: &ast::Generics,
134        after_where_clause: &ast::WhereClause,
135        bounds: &ast::GenericBounds,
136        ty: Option<&ast::Ty>,
137        vis: &ast::Visibility,
138        defaultness: ast::Defaultness,
139    ) {
140        let (cb, ib) = self.head("");
141        self.print_visibility(vis);
142        self.print_defaultness(defaultness);
143        self.word_space("type");
144        self.print_ident(ident);
145        self.print_generic_params(&generics.params);
146        if !bounds.is_empty() {
147            self.word_nbsp(":");
148            self.print_type_bounds(bounds);
149        }
150        self.print_where_clause(&generics.where_clause);
151        if let Some(ty) = ty {
152            self.space();
153            self.word_space("=");
154            self.print_type(ty);
155        }
156        self.print_where_clause(&after_where_clause);
157        self.word(";");
158        self.end(ib);
159        self.end(cb);
160    }
161
162    /// Pretty-prints an item.
163    pub(crate) fn print_item(&mut self, item: &ast::Item) {
164        if self.is_sdylib_interface && item.span.is_dummy() {
165            // Do not print prelude for interface files.
166            return;
167        }
168        self.hardbreak_if_not_bol();
169        self.maybe_print_comment(item.span.lo());
170        self.print_outer_attributes(&item.attrs);
171        self.ann.pre(self, AnnNode::Item(item));
172        match &item.kind {
173            ast::ItemKind::ExternCrate(orig_name, ident) => {
174                let (cb, ib) = self.head(visibility_qualified(&item.vis, "extern crate"));
175                if let &Some(orig_name) = orig_name {
176                    self.print_name(orig_name);
177                    self.space();
178                    self.word("as");
179                    self.space();
180                }
181                self.print_ident(*ident);
182                self.word(";");
183                self.end(ib);
184                self.end(cb);
185            }
186            ast::ItemKind::Use(tree) => {
187                self.print_visibility(&item.vis);
188                self.word_nbsp("use");
189                self.print_use_tree(tree);
190                self.word(";");
191            }
192            ast::ItemKind::Static(StaticItem {
193                ident,
194                ty,
195                safety,
196                mutability: mutbl,
197                expr: body,
198                define_opaque,
199                eii_impl,
200            }) => {
201                self.print_safety(*safety);
202                self.print_item_const(
203                    *ident,
204                    Some(*mutbl),
205                    &ast::Generics::default(),
206                    ty,
207                    body.as_deref(),
208                    &item.vis,
209                    ast::Safety::Default,
210                    ast::Defaultness::Implicit,
211                    define_opaque.as_deref(),
212                    eii_impl.as_deref(),
213                );
214            }
215            ast::ItemKind::ConstBlock(ast::ConstBlockItem { id: _, span: _, block }) => {
216                let ib = self.ibox(INDENT_UNIT);
217                self.word("const");
218                self.nbsp();
219                {
220                    let cb = self.cbox(0);
221                    let ib = self.ibox(0);
222                    self.print_block_with_attrs(block, &[], cb, ib);
223                }
224                self.end(ib);
225            }
226            ast::ItemKind::Const(ast::ConstItem {
227                defaultness,
228                ident,
229                generics,
230                ty,
231                body,
232                define_opaque,
233            }) => {
234                self.print_item_const(
235                    *ident,
236                    None,
237                    generics,
238                    ty,
239                    body.as_deref(),
240                    &item.vis,
241                    ast::Safety::Default,
242                    *defaultness,
243                    define_opaque.as_deref(),
244                    None,
245                );
246            }
247            ast::ItemKind::Fn(func) => {
248                self.print_fn_full(&item.vis, &item.attrs, &*func);
249            }
250            ast::ItemKind::Mod(safety, ident, mod_kind) => {
251                let (cb, ib) = self.head(Self::to_string(|s| {
252                    s.print_visibility(&item.vis);
253                    s.print_safety(*safety);
254                    s.word("mod");
255                }));
256                self.print_ident(*ident);
257
258                match mod_kind {
259                    ModKind::Loaded(items, ..) => {
260                        self.nbsp();
261                        self.bopen(ib);
262                        self.print_inner_attributes(&item.attrs);
263                        for item in items {
264                            self.print_item(item);
265                        }
266                        let empty = item.attrs.is_empty() && items.is_empty();
267                        self.bclose(item.span, empty, cb);
268                    }
269                    ModKind::Unloaded => {
270                        self.word(";");
271                        self.end(ib);
272                        self.end(cb);
273                    }
274                }
275            }
276            ast::ItemKind::ForeignMod(nmod) => {
277                let (cb, ib) = self.head(Self::to_string(|s| {
278                    s.print_safety(nmod.safety);
279                    s.word("extern");
280                }));
281                if let Some(abi) = nmod.abi {
282                    self.print_token_literal(abi.as_token_lit(), abi.span);
283                    self.nbsp();
284                }
285                self.bopen(ib);
286                self.print_foreign_mod(nmod, &item.attrs);
287                let empty = item.attrs.is_empty() && nmod.items.is_empty();
288                self.bclose(item.span, empty, cb);
289            }
290            ast::ItemKind::GlobalAsm(asm) => {
291                // FIXME: Print `builtin # global_asm` once macro `global_asm` uses `builtin_syntax`.
292                let (cb, ib) = self.head(visibility_qualified(&item.vis, "global_asm!"));
293                self.print_inline_asm(asm);
294                self.word(";");
295                self.end(ib);
296                self.end(cb);
297            }
298            ast::ItemKind::TyAlias(ast::TyAlias {
299                defaultness,
300                ident,
301                generics,
302                after_where_clause,
303                bounds,
304                ty,
305            }) => {
306                self.print_associated_type(
307                    *ident,
308                    generics,
309                    after_where_clause,
310                    bounds,
311                    ty.as_deref(),
312                    &item.vis,
313                    *defaultness,
314                );
315            }
316            ast::ItemKind::Enum(ident, generics, enum_definition) => {
317                self.print_enum_def(enum_definition, generics, *ident, item.span, &item.vis);
318            }
319            ast::ItemKind::Struct(ident, generics, struct_def) => {
320                let (cb, ib) = self.head(visibility_qualified(&item.vis, "struct"));
321                self.print_struct(struct_def, generics, *ident, item.span, true, cb, ib);
322            }
323            ast::ItemKind::Union(ident, generics, struct_def) => {
324                let (cb, ib) = self.head(visibility_qualified(&item.vis, "union"));
325                self.print_struct(struct_def, generics, *ident, item.span, true, cb, ib);
326            }
327            ast::ItemKind::Impl(ast::Impl { generics, of_trait, self_ty, items, constness }) => {
328                let (cb, ib) = self.head("");
329                self.print_visibility(&item.vis);
330
331                let impl_generics = |this: &mut Self| {
332                    this.word("impl");
333
334                    if generics.params.is_empty() {
335                        this.nbsp();
336                    } else {
337                        this.print_generic_params(&generics.params);
338                        this.space();
339                    }
340                };
341
342                if let Some(of_trait) = of_trait {
343                    let ast::TraitImplHeader { defaultness, safety, polarity, ref trait_ref } =
344                        *of_trait;
345                    self.print_defaultness(defaultness);
346                    self.print_constness(*constness);
347                    self.print_safety(safety);
348                    impl_generics(self);
349                    if let ast::ImplPolarity::Negative(_) = polarity {
350                        self.word("!");
351                    }
352                    self.print_trait_ref(trait_ref);
353                    self.space();
354                    self.word_space("for");
355                } else {
356                    self.print_constness(*constness);
357                    impl_generics(self);
358                }
359
360                self.print_type(self_ty);
361                self.print_where_clause(&generics.where_clause);
362
363                self.space();
364                self.bopen(ib);
365                self.print_inner_attributes(&item.attrs);
366                for impl_item in items {
367                    self.print_assoc_item(impl_item);
368                }
369                let empty = item.attrs.is_empty() && items.is_empty();
370                self.bclose(item.span, empty, cb);
371            }
372            ast::ItemKind::Trait(ast::Trait {
373                impl_restriction,
374                constness,
375                safety,
376                is_auto,
377                ident,
378                generics,
379                bounds,
380                items,
381            }) => {
382                let (cb, ib) = self.head("");
383                self.print_visibility(&item.vis);
384                self.print_impl_restriction(impl_restriction);
385                self.print_constness(*constness);
386                self.print_safety(*safety);
387                self.print_is_auto(*is_auto);
388                self.word_nbsp("trait");
389                self.print_ident(*ident);
390                self.print_generic_params(&generics.params);
391                if !bounds.is_empty() {
392                    self.word_nbsp(":");
393                    self.print_type_bounds(bounds);
394                }
395                self.print_where_clause(&generics.where_clause);
396                self.word(" ");
397                self.bopen(ib);
398                self.print_inner_attributes(&item.attrs);
399                for trait_item in items {
400                    self.print_assoc_item(trait_item);
401                }
402                let empty = item.attrs.is_empty() && items.is_empty();
403                self.bclose(item.span, empty, cb);
404            }
405            ast::ItemKind::TraitAlias(TraitAlias { constness, ident, generics, bounds }) => {
406                let (cb, ib) = self.head("");
407                self.print_visibility(&item.vis);
408                self.print_constness(*constness);
409                self.word_nbsp("trait");
410                self.print_ident(*ident);
411                self.print_generic_params(&generics.params);
412                self.nbsp();
413                if !bounds.is_empty() {
414                    self.word_nbsp("=");
415                    self.print_type_bounds(bounds);
416                }
417                self.print_where_clause(&generics.where_clause);
418                self.word(";");
419                self.end(ib);
420                self.end(cb);
421            }
422            ast::ItemKind::MacCall(mac) => {
423                self.print_mac(mac);
424                if mac.args.need_semicolon() {
425                    self.word(";");
426                }
427            }
428            ast::ItemKind::MacroDef(ident, macro_def) => {
429                self.print_mac_def(macro_def, &ident, item.span, |state| {
430                    state.print_visibility(&item.vis)
431                });
432            }
433            ast::ItemKind::Delegation(deleg) => self.print_delegation(
434                &item.attrs,
435                &item.vis,
436                &deleg.qself,
437                &deleg.path,
438                DelegationKind::Single,
439                &deleg.body,
440            ),
441            ast::ItemKind::DelegationMac(deleg) => self.print_delegation(
442                &item.attrs,
443                &item.vis,
444                &deleg.qself,
445                &deleg.prefix,
446                match &deleg.suffixes {
447                    ast::DelegationSuffixes::List(s) => DelegationKind::List(s),
448                    ast::DelegationSuffixes::Glob(_) => DelegationKind::Glob,
449                },
450                &deleg.body,
451            ),
452            ast::ItemKind::TestBinderConstraints(_) => {
453                self.word("test_binder_constraints!(/* pretty-printing not supported */)")
454            }
455        }
456        self.ann.post(self, AnnNode::Item(item))
457    }
458
459    fn print_enum_def(
460        &mut self,
461        enum_definition: &ast::EnumDef,
462        generics: &ast::Generics,
463        ident: Ident,
464        span: rustc_span::Span,
465        visibility: &ast::Visibility,
466    ) {
467        let (cb, ib) = self.head(visibility_qualified(visibility, "enum"));
468        self.print_ident(ident);
469        self.print_generic_params(&generics.params);
470        self.print_where_clause(&generics.where_clause);
471        self.space();
472        self.bopen(ib);
473        for v in enum_definition.variants.iter() {
474            self.space_if_not_bol();
475            self.maybe_print_comment(v.span.lo());
476            self.print_outer_attributes(&v.attrs);
477            let ib = self.ibox(0);
478            self.print_variant(v);
479            self.word(",");
480            self.end(ib);
481            self.maybe_print_trailing_comment(v.span, None);
482        }
483        let empty = enum_definition.variants.is_empty();
484        self.bclose(span, empty, cb)
485    }
486
487    pub(crate) fn print_visibility(&mut self, vis: &ast::Visibility) {
488        match &vis.kind {
489            ast::VisibilityKind::Public => self.word_nbsp("pub"),
490            ast::VisibilityKind::Restricted { path, shorthand, .. } => {
491                let path = Self::to_string(|s| s.print_path(path, false, 0));
492                if *shorthand && (path == "crate" || path == "self" || path == "super") {
493                    self.word_nbsp(::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("pub({0})", path))
    })format!("pub({path})"))
494                } else {
495                    self.word_nbsp(::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("pub(in {0})", path))
    })format!("pub(in {path})"))
496                }
497            }
498            ast::VisibilityKind::Inherited => {}
499        }
500    }
501
502    pub(crate) fn print_impl_restriction(&mut self, impl_restriction: &ast::ImplRestriction) {
503        match &impl_restriction.kind {
504            ast::RestrictionKind::Restricted { path, shorthand, .. } => {
505                let path = Self::to_string(|s| s.print_path(path, false, 0));
506                if *shorthand {
507                    self.word_nbsp(::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("impl({0})", path))
    })format!("impl({path})"))
508                } else {
509                    self.word_nbsp(::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("impl(in {0})", path))
    })format!("impl(in {path})"))
510                }
511            }
512            ast::RestrictionKind::Unrestricted => {}
513        }
514    }
515
516    pub(crate) fn print_mut_restriction(&mut self, mut_restriction: &ast::MutRestriction) {
517        match &mut_restriction.kind {
518            ast::RestrictionKind::Restricted { path, shorthand, .. } => {
519                let path = Self::to_string(|s| s.print_path(path, false, 0));
520                if *shorthand {
521                    self.word_nbsp(::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("mut({0})", path))
    })format!("mut({path})"))
522                } else {
523                    self.word_nbsp(::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("mut(in {0})", path))
    })format!("mut(in {path})"))
524                }
525            }
526            ast::RestrictionKind::Unrestricted => {}
527        }
528    }
529
530    fn print_defaultness(&mut self, defaultness: ast::Defaultness) {
531        if let ast::Defaultness::Default(_) = defaultness {
532            self.word_nbsp("default");
533        }
534    }
535
536    fn print_struct(
537        &mut self,
538        struct_def: &ast::VariantData,
539        generics: &ast::Generics,
540        ident: Ident,
541        span: rustc_span::Span,
542        print_finalizer: bool,
543        cb: BoxMarker,
544        ib: BoxMarker,
545    ) {
546        self.print_ident(ident);
547        self.print_generic_params(&generics.params);
548        match &struct_def {
549            ast::VariantData::Tuple(..) | ast::VariantData::Unit(..) => {
550                if let ast::VariantData::Tuple(..) = struct_def {
551                    self.popen();
552                    self.commasep(Inconsistent, struct_def.fields(), |s, field| {
553                        s.maybe_print_comment(field.span.lo());
554                        s.print_outer_attributes(&field.attrs);
555                        s.print_visibility(&field.vis);
556                        s.print_mut_restriction(field.mut_restriction());
557                        s.print_type(&field.ty)
558                    });
559                    self.pclose();
560                }
561                self.print_where_clause(&generics.where_clause);
562                if print_finalizer {
563                    self.word(";");
564                }
565                self.end(ib);
566                self.end(cb);
567            }
568            ast::VariantData::Struct { fields, .. } => {
569                self.print_where_clause(&generics.where_clause);
570                self.nbsp();
571                self.bopen(ib);
572
573                let empty = fields.is_empty();
574                if !empty {
575                    self.hardbreak_if_not_bol();
576
577                    for field in fields {
578                        self.hardbreak_if_not_bol();
579                        self.maybe_print_comment(field.span.lo());
580                        self.print_outer_attributes(&field.attrs);
581                        self.print_visibility(&field.vis);
582                        self.print_mut_restriction(field.mut_restriction());
583                        self.print_ident(field.ident.unwrap());
584                        self.word_nbsp(":");
585                        self.print_type(&field.ty);
586                        self.word(",");
587                    }
588                }
589
590                self.bclose(span, empty, cb);
591            }
592        }
593    }
594
595    pub(crate) fn print_variant(&mut self, v: &ast::Variant) {
596        let (cb, ib) = self.head("");
597        self.print_visibility(&v.vis);
598        let generics = ast::Generics::default();
599        self.print_struct(&v.data, &generics, v.ident, v.span, false, cb, ib);
600        if let Some(d) = &v.disr_expr {
601            self.space();
602            self.word_space("=");
603            self.print_expr(&d.value, FixupContext::default())
604        }
605    }
606
607    pub(crate) fn print_assoc_item(&mut self, item: &ast::AssocItem) {
608        let ast::Item { id, span, ref attrs, ref kind, ref vis, tokens: _ } = *item;
609        self.ann.pre(self, AnnNode::SubItem(id));
610        self.hardbreak_if_not_bol();
611        self.maybe_print_comment(span.lo());
612        self.print_outer_attributes(attrs);
613        match kind {
614            ast::AssocItemKind::Fn(func) => {
615                self.print_fn_full(vis, attrs, &*func);
616            }
617            ast::AssocItemKind::Const(ast::ConstItem {
618                defaultness,
619                ident,
620                generics,
621                ty,
622                body,
623                define_opaque,
624            }) => {
625                self.print_item_const(
626                    *ident,
627                    None,
628                    generics,
629                    ty,
630                    body.as_deref(),
631                    vis,
632                    ast::Safety::Default,
633                    *defaultness,
634                    define_opaque.as_deref(),
635                    None,
636                );
637            }
638            ast::AssocItemKind::Type(ast::TyAlias {
639                defaultness,
640                ident,
641                generics,
642                after_where_clause,
643                bounds,
644                ty,
645            }) => {
646                self.print_associated_type(
647                    *ident,
648                    generics,
649                    after_where_clause,
650                    bounds,
651                    ty.as_deref(),
652                    vis,
653                    *defaultness,
654                );
655            }
656            ast::AssocItemKind::MacCall(m) => {
657                self.print_mac(m);
658                if m.args.need_semicolon() {
659                    self.word(";");
660                }
661            }
662            ast::AssocItemKind::Delegation(deleg) => self.print_delegation(
663                &item.attrs,
664                vis,
665                &deleg.qself,
666                &deleg.path,
667                DelegationKind::Single,
668                &deleg.body,
669            ),
670            ast::AssocItemKind::DelegationMac(deleg) => self.print_delegation(
671                &item.attrs,
672                vis,
673                &deleg.qself,
674                &deleg.prefix,
675                match &deleg.suffixes {
676                    ast::DelegationSuffixes::List(s) => DelegationKind::List(s),
677                    ast::DelegationSuffixes::Glob(_) => DelegationKind::Glob,
678                },
679                &deleg.body,
680            ),
681        }
682        self.ann.post(self, AnnNode::SubItem(id))
683    }
684
685    fn print_delegation(
686        &mut self,
687        attrs: &[ast::Attribute],
688        vis: &ast::Visibility,
689        qself: &Option<Box<ast::QSelf>>,
690        path: &ast::Path,
691        kind: DelegationKind<'_>,
692        body: &Option<Box<ast::Block>>,
693    ) {
694        let body_cb_ib = body.as_ref().map(|body| (body, self.head("")));
695        self.print_visibility(vis);
696        self.word_nbsp("reuse");
697
698        if let Some(qself) = qself {
699            self.print_qpath(path, qself, false);
700        } else {
701            self.print_path(path, false, 0);
702        }
703        match kind {
704            DelegationKind::Single => {}
705            DelegationKind::List(suffixes) => {
706                self.word("::");
707                self.word("{");
708                for (i, (ident, rename)) in suffixes.iter().enumerate() {
709                    self.print_ident(*ident);
710                    if let Some(rename) = rename {
711                        self.nbsp();
712                        self.word_nbsp("as");
713                        self.print_ident(*rename);
714                    }
715                    if i != suffixes.len() - 1 {
716                        self.word_space(",");
717                    }
718                }
719                self.word("}");
720            }
721            DelegationKind::Glob => {
722                self.word("::");
723                self.word("*");
724            }
725        }
726        if let Some((body, (cb, ib))) = body_cb_ib {
727            self.nbsp();
728            self.print_block_with_attrs(body, attrs, cb, ib);
729        } else {
730            self.word(";");
731        }
732    }
733
734    fn print_fn_full(&mut self, vis: &ast::Visibility, attrs: &[ast::Attribute], func: &ast::Fn) {
735        let ast::Fn { defaultness, ident, generics, sig, contract, body, define_opaque, eii_impl } =
736            func;
737
738        self.print_define_opaques(define_opaque.as_deref());
739
740        if let Some(eii_impl) = eii_impl {
741            self.print_eii_impl(eii_impl);
742        }
743
744        let body_cb_ib = body.as_ref().map(|body| (body, self.head("")));
745
746        self.print_visibility(vis);
747        self.print_defaultness(*defaultness);
748        self.print_fn(&sig.decl, sig.header, Some(*ident), generics);
749        if let Some(contract) = &contract {
750            self.nbsp();
751            self.print_contract(contract);
752        }
753        if let Some((body, (cb, ib))) = body_cb_ib {
754            if self.is_sdylib_interface {
755                self.word(";");
756                self.end(ib); // end inner head-block
757                self.end(cb); // end outer head-block
758                return;
759            }
760
761            self.nbsp();
762            self.print_block_with_attrs(body, attrs, cb, ib);
763        } else {
764            self.word(";");
765        }
766    }
767
768    fn print_eii_impl(&mut self, eii: &ast::EiiImpl) {
769        self.word("#[");
770        if let Safety::Unsafe(..) = eii.impl_safety {
771            self.word("unsafe");
772            self.popen();
773        }
774        self.print_path(&eii.eii_macro_path, false, 0);
775        if let Safety::Unsafe(..) = eii.impl_safety {
776            self.pclose();
777        }
778        self.word("]");
779        self.hardbreak();
780    }
781
782    fn print_define_opaques(&mut self, define_opaque: Option<&[(ast::NodeId, ast::Path)]>) {
783        if let Some(define_opaque) = define_opaque {
784            self.word("#[define_opaque(");
785            for (i, (_, path)) in define_opaque.iter().enumerate() {
786                if i != 0 {
787                    self.word_space(",");
788                }
789
790                self.print_path(path, false, 0);
791            }
792            self.word(")]");
793        }
794        self.hardbreak_if_not_bol();
795    }
796
797    fn print_contract(&mut self, contract: &ast::FnContract) {
798        if let Some(pred) = &contract.requires {
799            self.word("rustc_requires");
800            self.popen();
801            self.print_expr(pred, FixupContext::default());
802            self.pclose();
803        }
804        if let Some(pred) = &contract.ensures {
805            self.word("rustc_ensures");
806            self.popen();
807            self.print_expr(pred, FixupContext::default());
808            self.pclose();
809        }
810    }
811
812    pub(crate) fn print_fn(
813        &mut self,
814        decl: &ast::FnDecl,
815        header: ast::FnHeader,
816        ident: Option<Ident>,
817        generics: &ast::Generics,
818    ) {
819        self.print_fn_header_info(header);
820        if let Some(ident) = ident {
821            self.nbsp();
822            self.print_ident(ident);
823        }
824        self.print_generic_params(&generics.params);
825        self.print_fn_params_and_ret(decl, false);
826        self.print_where_clause(&generics.where_clause);
827    }
828
829    pub(crate) fn print_fn_params_and_ret(&mut self, decl: &ast::FnDecl, is_closure: bool) {
830        let (open, close) = if is_closure { ("|", "|") } else { ("(", ")") };
831        self.word(open);
832        self.commasep(Inconsistent, &decl.inputs, |s, param| s.print_param(param, is_closure));
833        self.word(close);
834        self.print_fn_ret_ty(&decl.output)
835    }
836
837    fn print_where_clause(&mut self, where_clause: &ast::WhereClause) {
838        let ast::WhereClause { has_where_token, ref predicates, span: _ } = *where_clause;
839        if predicates.is_empty() && !has_where_token {
840            return;
841        }
842
843        self.space();
844        self.word_space("where");
845
846        for (i, predicate) in predicates.iter().enumerate() {
847            if i != 0 {
848                self.word_space(",");
849            }
850
851            self.print_where_predicate(predicate);
852        }
853    }
854
855    pub fn print_where_predicate(&mut self, predicate: &ast::WherePredicate) {
856        let ast::WherePredicate { attrs, kind, id: _, span: _, is_placeholder: _ } = predicate;
857        self.print_outer_attributes(attrs);
858        match kind {
859            ast::WherePredicateKind::BoundPredicate(where_bound_predicate) => {
860                self.print_where_bound_predicate(where_bound_predicate);
861            }
862            ast::WherePredicateKind::RegionPredicate(ast::WhereRegionPredicate {
863                lifetime,
864                bounds,
865                ..
866            }) => {
867                self.print_lifetime(*lifetime);
868                self.word(":");
869                if !bounds.is_empty() {
870                    self.nbsp();
871                    self.print_lifetime_bounds(bounds);
872                }
873            }
874        }
875    }
876
877    pub(crate) fn print_where_bound_predicate(
878        &mut self,
879        where_bound_predicate: &ast::WhereBoundPredicate,
880    ) {
881        self.print_formal_generic_params(&where_bound_predicate.bound_generic_params);
882        self.print_type(&where_bound_predicate.bounded_ty);
883        self.word(":");
884        if !where_bound_predicate.bounds.is_empty() {
885            self.nbsp();
886            self.print_type_bounds(&where_bound_predicate.bounds);
887        }
888    }
889
890    fn print_use_tree(&mut self, tree: &ast::UseTree) {
891        match &tree.kind {
892            ast::UseTreeKind::Simple(rename) => {
893                self.print_path(&tree.prefix, false, 0);
894                if let &Some(rename) = rename {
895                    self.nbsp();
896                    self.word_nbsp("as");
897                    self.print_ident(rename);
898                }
899            }
900            ast::UseTreeKind::Glob(_) => {
901                if !tree.prefix.segments.is_empty() {
902                    self.print_path(&tree.prefix, false, 0);
903                    self.word("::");
904                }
905                self.word("*");
906            }
907            ast::UseTreeKind::Nested { items, .. } => {
908                if !tree.prefix.segments.is_empty() {
909                    self.print_path(&tree.prefix, false, 0);
910                    self.word("::");
911                }
912                if items.is_empty() {
913                    self.word("{}");
914                } else if let [(item, _)] = items.as_slice()
915                    && !item
916                        .prefix
917                        .segments
918                        .first()
919                        .is_some_and(|seg| seg.ident.name == rustc_span::symbol::kw::SelfLower)
920                {
921                    self.print_use_tree(item);
922                } else {
923                    let cb = self.cbox(INDENT_UNIT);
924                    self.word("{");
925                    self.zerobreak();
926                    let ib = self.ibox(0);
927                    for (idx, use_tree) in items.iter().enumerate() {
928                        let is_last = idx == items.len() - 1;
929                        self.print_use_tree(&use_tree.0);
930                        if !is_last {
931                            self.word(",");
932                            if let ast::UseTreeKind::Nested { .. } = use_tree.0.kind {
933                                self.hardbreak();
934                            } else {
935                                self.space();
936                            }
937                        }
938                    }
939                    self.end(ib);
940                    self.trailing_comma();
941                    self.offset(-INDENT_UNIT);
942                    self.word("}");
943                    self.end(cb);
944                }
945            }
946        }
947    }
948}