php_ast/owned/
visitor.rs

1//! Visitor infrastructure for owned (lifetime-free) PHP AST traversal.
2//!
3//! This module mirrors [`crate::visitor`] but operates on the owned AST types
4//! in [`crate::owned`] rather than the arena-allocated types. Use it after
5//! calling [`php_rs_parser::parse()`] — no arena or lifetime management needed.
6//!
7//! # Example
8//!
9//! ```
10//! use php_ast::owned::visitor::{OwnedVisitor, walk_owned_expr};
11//! use php_ast::owned::{Expr, ExprKind};
12//! use std::ops::ControlFlow;
13//!
14//! struct VarCounter { count: usize }
15//!
16//! impl OwnedVisitor for VarCounter {
17//!     fn visit_expr(&mut self, expr: &Expr) -> ControlFlow<()> {
18//!         if matches!(&expr.kind, ExprKind::Variable(_)) {
19//!             self.count += 1;
20//!         }
21//!         walk_owned_expr(self, expr)
22//!     }
23//! }
24//! ```
25
26use std::ops::ControlFlow;
27
28use super::*;
29
30// =============================================================================
31// OwnedVisitor trait
32// =============================================================================
33
34/// Visitor trait for immutable traversal of owned (lifetime-free) AST nodes.
35///
36/// All methods return `ControlFlow<()>`:
37/// - `ControlFlow::Continue(())` — keep walking.
38/// - `ControlFlow::Break(())` — stop the entire traversal immediately.
39///
40/// Default implementations recurse into child nodes, so implementors only need
41/// to override the node types they care about.
42///
43/// To **skip** a subtree, override the method and return `Continue(())`
44/// without calling the corresponding `walk_owned_*` function.
45pub trait OwnedVisitor {
46    fn visit_program(&mut self, program: &Program) -> ControlFlow<()> {
47        walk_owned_program(self, program)
48    }
49
50    fn visit_stmt(&mut self, stmt: &Stmt) -> ControlFlow<()> {
51        walk_owned_stmt(self, stmt)
52    }
53
54    fn visit_block(&mut self, block: &Block) -> ControlFlow<()> {
55        walk_owned_block(self, block)
56    }
57
58    fn visit_expr(&mut self, expr: &Expr) -> ControlFlow<()> {
59        walk_owned_expr(self, expr)
60    }
61
62    fn visit_param(&mut self, param: &Param) -> ControlFlow<()> {
63        walk_owned_param(self, param)
64    }
65
66    fn visit_arg(&mut self, arg: &Arg) -> ControlFlow<()> {
67        walk_owned_arg(self, arg)
68    }
69
70    fn visit_class_member(&mut self, member: &ClassMember) -> ControlFlow<()> {
71        walk_owned_class_member(self, member)
72    }
73
74    fn visit_enum_member(&mut self, member: &EnumMember) -> ControlFlow<()> {
75        walk_owned_enum_member(self, member)
76    }
77
78    fn visit_property_hook(&mut self, hook: &PropertyHook) -> ControlFlow<()> {
79        walk_owned_property_hook(self, hook)
80    }
81
82    fn visit_type_hint(&mut self, type_hint: &TypeHint) -> ControlFlow<()> {
83        walk_owned_type_hint(self, type_hint)
84    }
85
86    fn visit_attribute(&mut self, attribute: &Attribute) -> ControlFlow<()> {
87        walk_owned_attribute(self, attribute)
88    }
89
90    fn visit_catch_clause(&mut self, catch: &CatchClause) -> ControlFlow<()> {
91        walk_owned_catch_clause(self, catch)
92    }
93
94    fn visit_match_arm(&mut self, arm: &MatchArm) -> ControlFlow<()> {
95        walk_owned_match_arm(self, arm)
96    }
97
98    fn visit_closure_use_var(&mut self, _var: &ClosureUseVar) -> ControlFlow<()> {
99        ControlFlow::Continue(())
100    }
101
102    fn visit_trait_use(&mut self, trait_use: &TraitUseDecl) -> ControlFlow<()> {
103        walk_owned_trait_use(self, trait_use)
104    }
105
106    fn visit_trait_adaptation(&mut self, _adaptation: &TraitAdaptation) -> ControlFlow<()> {
107        ControlFlow::Continue(())
108    }
109
110    fn visit_name(&mut self, _name: &Name) -> ControlFlow<()> {
111        ControlFlow::Continue(())
112    }
113
114    fn visit_comment(&mut self, _comment: &Comment) -> ControlFlow<()> {
115        ControlFlow::Continue(())
116    }
117}
118
119// =============================================================================
120// Walk functions
121// =============================================================================
122
123/// Calls [`OwnedVisitor::visit_name`] on `name`.
124///
125/// `Name` is a leaf node — there are no child nodes to recurse into.
126/// This function exists for symmetry with [`walk_owned_expr`] and friends so
127/// that an override of [`OwnedVisitor::visit_name`] can call the default
128/// behaviour by name.
129pub fn walk_owned_name<V: OwnedVisitor + ?Sized>(visitor: &mut V, name: &Name) -> ControlFlow<()> {
130    visitor.visit_name(name)
131}
132
133/// Calls [`OwnedVisitor::visit_comment`] for each comment in `comments`.
134pub fn walk_owned_comments<V: OwnedVisitor + ?Sized>(
135    visitor: &mut V,
136    comments: &[Comment],
137) -> ControlFlow<()> {
138    for comment in comments {
139        visitor.visit_comment(comment)?;
140    }
141    ControlFlow::Continue(())
142}
143
144/// Visits every top-level statement in `program`.
145pub fn walk_owned_program<V: OwnedVisitor + ?Sized>(
146    visitor: &mut V,
147    program: &Program,
148) -> ControlFlow<()> {
149    for stmt in program.stmts.iter() {
150        visitor.visit_stmt(stmt)?;
151    }
152    ControlFlow::Continue(())
153}
154
155/// Dispatches `stmt` to the appropriate child visitors based on its [`StmtKind`].
156pub fn walk_owned_block<V: OwnedVisitor + ?Sized>(
157    visitor: &mut V,
158    block: &Block,
159) -> ControlFlow<()> {
160    for stmt in block.stmts.iter() {
161        visitor.visit_stmt(stmt)?;
162    }
163    ControlFlow::Continue(())
164}
165
166pub fn walk_owned_stmt<V: OwnedVisitor + ?Sized>(visitor: &mut V, stmt: &Stmt) -> ControlFlow<()> {
167    match &stmt.kind {
168        StmtKind::Expression(expr) => {
169            visitor.visit_expr(expr)?;
170        }
171        StmtKind::Echo(exprs) => {
172            for expr in exprs.iter() {
173                visitor.visit_expr(expr)?;
174            }
175        }
176        StmtKind::Return(expr) => {
177            if let Some(expr) = expr {
178                visitor.visit_expr(expr)?;
179            }
180        }
181        StmtKind::Block(block) => {
182            visitor.visit_block(block)?;
183        }
184        StmtKind::If(if_stmt) => {
185            visitor.visit_expr(&if_stmt.condition)?;
186            visitor.visit_stmt(&if_stmt.then_branch)?;
187            for elseif in if_stmt.elseif_branches.iter() {
188                visitor.visit_expr(&elseif.condition)?;
189                visitor.visit_stmt(&elseif.body)?;
190            }
191            if let Some(else_branch) = &if_stmt.else_branch {
192                visitor.visit_stmt(else_branch)?;
193            }
194        }
195        StmtKind::While(while_stmt) => {
196            visitor.visit_expr(&while_stmt.condition)?;
197            visitor.visit_stmt(&while_stmt.body)?;
198        }
199        StmtKind::For(for_stmt) => {
200            for expr in for_stmt.init.iter() {
201                visitor.visit_expr(expr)?;
202            }
203            for expr in for_stmt.condition.iter() {
204                visitor.visit_expr(expr)?;
205            }
206            for expr in for_stmt.update.iter() {
207                visitor.visit_expr(expr)?;
208            }
209            visitor.visit_stmt(&for_stmt.body)?;
210        }
211        StmtKind::Foreach(foreach_stmt) => {
212            visitor.visit_expr(&foreach_stmt.expr)?;
213            if let Some(key) = &foreach_stmt.key {
214                visitor.visit_expr(key)?;
215            }
216            visitor.visit_expr(&foreach_stmt.value)?;
217            visitor.visit_stmt(&foreach_stmt.body)?;
218        }
219        StmtKind::DoWhile(do_while) => {
220            visitor.visit_stmt(&do_while.body)?;
221            visitor.visit_expr(&do_while.condition)?;
222        }
223        StmtKind::Function(func) => {
224            walk_owned_function_like(visitor, &func.attributes, &func.params, &func.return_type)?;
225            visitor.visit_block(&func.body)?;
226        }
227        StmtKind::Break(expr) | StmtKind::Continue(expr) => {
228            if let Some(expr) = expr {
229                visitor.visit_expr(expr)?;
230            }
231        }
232        StmtKind::Switch(switch_stmt) => {
233            visitor.visit_expr(&switch_stmt.expr)?;
234            for case in switch_stmt.body.cases.iter() {
235                if let Some(value) = &case.value {
236                    visitor.visit_expr(value)?;
237                }
238                for stmt in case.body.iter() {
239                    visitor.visit_stmt(stmt)?;
240                }
241            }
242        }
243        StmtKind::Throw(expr) => {
244            visitor.visit_expr(expr)?;
245        }
246        StmtKind::TryCatch(tc) => {
247            visitor.visit_block(&tc.body)?;
248            for catch in tc.catches.iter() {
249                visitor.visit_catch_clause(catch)?;
250            }
251            if let Some(finally) = &tc.finally {
252                visitor.visit_block(finally)?;
253            }
254        }
255        StmtKind::Declare(decl) => {
256            for (_, expr) in decl.directives.iter() {
257                visitor.visit_expr(expr)?;
258            }
259            if let Some(body) = &decl.body {
260                visitor.visit_stmt(body)?;
261            }
262        }
263        StmtKind::Unset(exprs) | StmtKind::Global(exprs) => {
264            for expr in exprs.iter() {
265                visitor.visit_expr(expr)?;
266            }
267        }
268        StmtKind::Class(class) => {
269            walk_owned_attributes(visitor, &class.attributes)?;
270            if let Some(extends) = &class.extends {
271                visitor.visit_name(extends)?;
272            }
273            for name in class.implements.iter() {
274                visitor.visit_name(name)?;
275            }
276            for member in class.body.members.iter() {
277                visitor.visit_class_member(member)?;
278            }
279        }
280        StmtKind::Interface(iface) => {
281            walk_owned_attributes(visitor, &iface.attributes)?;
282            for name in iface.extends.iter() {
283                visitor.visit_name(name)?;
284            }
285            for member in iface.body.members.iter() {
286                visitor.visit_class_member(member)?;
287            }
288        }
289        StmtKind::Trait(trait_decl) => {
290            walk_owned_attributes(visitor, &trait_decl.attributes)?;
291            for member in trait_decl.body.members.iter() {
292                visitor.visit_class_member(member)?;
293            }
294        }
295        StmtKind::Enum(enum_decl) => {
296            walk_owned_attributes(visitor, &enum_decl.attributes)?;
297            if let Some(scalar_type) = &enum_decl.scalar_type {
298                visitor.visit_name(scalar_type)?;
299            }
300            for name in enum_decl.implements.iter() {
301                visitor.visit_name(name)?;
302            }
303            for member in enum_decl.body.members.iter() {
304                visitor.visit_enum_member(member)?;
305            }
306        }
307        StmtKind::Namespace(ns) => {
308            if let NamespaceBody::Braced(block) = &ns.body {
309                visitor.visit_block(block)?;
310            }
311        }
312        StmtKind::Const(items) => {
313            for item in items.iter() {
314                walk_owned_attributes(visitor, &item.attributes)?;
315                visitor.visit_expr(&item.value)?;
316            }
317        }
318        StmtKind::StaticVar(vars) => {
319            for var in vars.iter() {
320                if let Some(default) = &var.default {
321                    visitor.visit_expr(default)?;
322                }
323            }
324        }
325        StmtKind::Use(decl) => {
326            for item in decl.uses.iter() {
327                visitor.visit_name(&item.name)?;
328            }
329        }
330        StmtKind::Goto(_)
331        | StmtKind::Label(_)
332        | StmtKind::Nop
333        | StmtKind::InlineHtml(_)
334        | StmtKind::HaltCompiler(_)
335        | StmtKind::Error => {}
336    }
337    ControlFlow::Continue(())
338}
339
340/// Dispatches `expr` to the appropriate child visitors based on its [`ExprKind`].
341pub fn walk_owned_expr<V: OwnedVisitor + ?Sized>(visitor: &mut V, expr: &Expr) -> ControlFlow<()> {
342    match &expr.kind {
343        ExprKind::Assign(assign) => {
344            visitor.visit_expr(&assign.target)?;
345            visitor.visit_expr(&assign.value)?;
346        }
347        ExprKind::Binary(binary) => {
348            visitor.visit_expr(&binary.left)?;
349            visitor.visit_expr(&binary.right)?;
350        }
351        ExprKind::UnaryPrefix(unary) => {
352            visitor.visit_expr(&unary.operand)?;
353        }
354        ExprKind::UnaryPostfix(unary) => {
355            visitor.visit_expr(&unary.operand)?;
356        }
357        ExprKind::Ternary(ternary) => {
358            visitor.visit_expr(&ternary.condition)?;
359            if let Some(then_expr) = &ternary.then_expr {
360                visitor.visit_expr(then_expr)?;
361            }
362            visitor.visit_expr(&ternary.else_expr)?;
363        }
364        ExprKind::NullCoalesce(nc) => {
365            visitor.visit_expr(&nc.left)?;
366            visitor.visit_expr(&nc.right)?;
367        }
368        ExprKind::FunctionCall(call) => {
369            visitor.visit_expr(&call.name)?;
370            for arg in call.args.iter() {
371                visitor.visit_arg(arg)?;
372            }
373        }
374        ExprKind::Array(elements) => {
375            for elem in elements.iter() {
376                if let Some(key) = &elem.key {
377                    visitor.visit_expr(key)?;
378                }
379                visitor.visit_expr(&elem.value)?;
380            }
381        }
382        ExprKind::ArrayAccess(access) => {
383            visitor.visit_expr(&access.array)?;
384            if let Some(index) = &access.index {
385                visitor.visit_expr(index)?;
386            }
387        }
388        ExprKind::Print(expr) => {
389            visitor.visit_expr(expr)?;
390        }
391        ExprKind::Parenthesized(expr) => {
392            visitor.visit_expr(expr)?;
393        }
394        ExprKind::Cast(_, expr) => {
395            visitor.visit_expr(expr)?;
396        }
397        ExprKind::ErrorSuppress(expr) => {
398            visitor.visit_expr(expr)?;
399        }
400        ExprKind::Isset(exprs) => {
401            for expr in exprs.iter() {
402                visitor.visit_expr(expr)?;
403            }
404        }
405        ExprKind::Empty(expr) => {
406            visitor.visit_expr(expr)?;
407        }
408        ExprKind::Include(_, expr) => {
409            visitor.visit_expr(expr)?;
410        }
411        ExprKind::Eval(expr) => {
412            visitor.visit_expr(expr)?;
413        }
414        ExprKind::Exit(expr) => {
415            if let Some(expr) = expr {
416                visitor.visit_expr(expr)?;
417            }
418        }
419        ExprKind::Clone(expr) => {
420            visitor.visit_expr(expr)?;
421        }
422        ExprKind::CloneWith(object, overrides) => {
423            visitor.visit_expr(object)?;
424            visitor.visit_expr(overrides)?;
425        }
426        ExprKind::New(new_expr) => {
427            visitor.visit_expr(&new_expr.class)?;
428            for arg in new_expr.args.iter() {
429                visitor.visit_arg(arg)?;
430            }
431        }
432        ExprKind::PropertyAccess(access) | ExprKind::NullsafePropertyAccess(access) => {
433            visitor.visit_expr(&access.object)?;
434            visitor.visit_expr(&access.property)?;
435        }
436        ExprKind::MethodCall(call) | ExprKind::NullsafeMethodCall(call) => {
437            visitor.visit_expr(&call.object)?;
438            visitor.visit_expr(&call.method)?;
439            for arg in call.args.iter() {
440                visitor.visit_arg(arg)?;
441            }
442        }
443        ExprKind::StaticPropertyAccess(access) | ExprKind::ClassConstAccess(access) => {
444            visitor.visit_expr(&access.class)?;
445            visitor.visit_expr(&access.member)?;
446        }
447        ExprKind::ClassConstAccessDynamic { class, member }
448        | ExprKind::StaticPropertyAccessDynamic { class, member } => {
449            visitor.visit_expr(class)?;
450            visitor.visit_expr(member)?;
451        }
452        ExprKind::StaticMethodCall(call) => {
453            visitor.visit_expr(&call.class)?;
454            visitor.visit_expr(&call.method)?;
455            for arg in call.args.iter() {
456                visitor.visit_arg(arg)?;
457            }
458        }
459        ExprKind::StaticDynMethodCall(call) => {
460            visitor.visit_expr(&call.class)?;
461            visitor.visit_expr(&call.method)?;
462            for arg in call.args.iter() {
463                visitor.visit_arg(arg)?;
464            }
465        }
466        ExprKind::Closure(closure) => {
467            walk_owned_function_like(
468                visitor,
469                &closure.attributes,
470                &closure.params,
471                &closure.return_type,
472            )?;
473            for use_var in closure.use_vars.iter() {
474                visitor.visit_closure_use_var(use_var)?;
475            }
476            visitor.visit_block(&closure.body)?;
477        }
478        ExprKind::ArrowFunction(arrow) => {
479            walk_owned_function_like(
480                visitor,
481                &arrow.attributes,
482                &arrow.params,
483                &arrow.return_type,
484            )?;
485            visitor.visit_expr(&arrow.body)?;
486        }
487        ExprKind::Match(match_expr) => {
488            visitor.visit_expr(&match_expr.subject)?;
489            for arm in match_expr.arms.iter() {
490                visitor.visit_match_arm(arm)?;
491            }
492        }
493        ExprKind::ThrowExpr(expr) => {
494            visitor.visit_expr(expr)?;
495        }
496        ExprKind::Yield(yield_expr) => {
497            if let Some(key) = &yield_expr.key {
498                visitor.visit_expr(key)?;
499            }
500            if let Some(value) = &yield_expr.value {
501                visitor.visit_expr(value)?;
502            }
503        }
504        ExprKind::AnonymousClass(class) => {
505            walk_owned_attributes(visitor, &class.attributes)?;
506            for member in class.body.members.iter() {
507                visitor.visit_class_member(member)?;
508            }
509        }
510        ExprKind::InterpolatedString(parts) | ExprKind::ShellExec(parts) => {
511            for part in parts.iter() {
512                if let StringPart::Expr(e) = part {
513                    visitor.visit_expr(e)?;
514                }
515            }
516        }
517        ExprKind::Heredoc { parts, .. } => {
518            for part in parts.iter() {
519                if let StringPart::Expr(e) = part {
520                    visitor.visit_expr(e)?;
521                }
522            }
523        }
524        ExprKind::VariableVariable(inner) => {
525            visitor.visit_expr(inner)?;
526        }
527        ExprKind::CallableCreate(cc) => match &cc.kind {
528            CallableCreateKind::Function(name) => visitor.visit_expr(name)?,
529            CallableCreateKind::Method { object, method }
530            | CallableCreateKind::NullsafeMethod { object, method } => {
531                visitor.visit_expr(object)?;
532                visitor.visit_expr(method)?;
533            }
534            CallableCreateKind::StaticMethod { class, method } => {
535                visitor.visit_expr(class)?;
536                visitor.visit_expr(method)?;
537            }
538        },
539        ExprKind::Int(_)
540        | ExprKind::Float(_)
541        | ExprKind::String(_)
542        | ExprKind::Bool(_)
543        | ExprKind::Null
544        | ExprKind::Omit
545        | ExprKind::Variable(_)
546        | ExprKind::Identifier(_)
547        | ExprKind::MagicConst(_)
548        | ExprKind::Nowdoc { .. }
549        | ExprKind::Error => {}
550    }
551    ControlFlow::Continue(())
552}
553
554/// Visits a function/method parameter's attributes, type hint, default, and hooks.
555pub fn walk_owned_param<V: OwnedVisitor + ?Sized>(
556    visitor: &mut V,
557    param: &Param,
558) -> ControlFlow<()> {
559    walk_owned_attributes(visitor, &param.attributes)?;
560    if let Some(type_hint) = &param.type_hint {
561        visitor.visit_type_hint(type_hint)?;
562    }
563    if let Some(default) = &param.default {
564        visitor.visit_expr(default)?;
565    }
566    for hook in param.hooks.iter() {
567        visitor.visit_property_hook(hook)?;
568    }
569    ControlFlow::Continue(())
570}
571
572/// Visits the value expression of a call argument.
573pub fn walk_owned_arg<V: OwnedVisitor + ?Sized>(visitor: &mut V, arg: &Arg) -> ControlFlow<()> {
574    visitor.visit_expr(&arg.value)
575}
576
577/// Dispatches a class member to its child visitors.
578pub fn walk_owned_class_member<V: OwnedVisitor + ?Sized>(
579    visitor: &mut V,
580    member: &ClassMember,
581) -> ControlFlow<()> {
582    match &member.kind {
583        ClassMemberKind::Property(prop) => {
584            walk_owned_property_decl(visitor, prop)?;
585        }
586        ClassMemberKind::Method(method) => {
587            walk_owned_method_decl(visitor, method)?;
588        }
589        ClassMemberKind::ClassConst(cc) => {
590            walk_owned_class_const_decl(visitor, cc)?;
591        }
592        ClassMemberKind::TraitUse(trait_use) => {
593            visitor.visit_trait_use(trait_use)?;
594        }
595    }
596    ControlFlow::Continue(())
597}
598
599/// Visits a property hook's attributes, parameters, and body.
600pub fn walk_owned_property_hook<V: OwnedVisitor + ?Sized>(
601    visitor: &mut V,
602    hook: &PropertyHook,
603) -> ControlFlow<()> {
604    walk_owned_attributes(visitor, &hook.attributes)?;
605    for param in hook.params.iter() {
606        visitor.visit_param(param)?;
607    }
608    match &hook.body {
609        PropertyHookBody::Block(block) => {
610            visitor.visit_block(block)?;
611        }
612        PropertyHookBody::Expression(expr) => {
613            visitor.visit_expr(expr)?;
614        }
615        PropertyHookBody::Abstract => {}
616    }
617    ControlFlow::Continue(())
618}
619
620/// Dispatches an enum member to its child visitors.
621pub fn walk_owned_enum_member<V: OwnedVisitor + ?Sized>(
622    visitor: &mut V,
623    member: &EnumMember,
624) -> ControlFlow<()> {
625    match &member.kind {
626        EnumMemberKind::Case(case) => {
627            walk_owned_attributes(visitor, &case.attributes)?;
628            if let Some(value) = &case.value {
629                visitor.visit_expr(value)?;
630            }
631        }
632        EnumMemberKind::Method(method) => {
633            walk_owned_method_decl(visitor, method)?;
634        }
635        EnumMemberKind::ClassConst(cc) => {
636            walk_owned_class_const_decl(visitor, cc)?;
637        }
638        EnumMemberKind::TraitUse(trait_use) => {
639            visitor.visit_trait_use(trait_use)?;
640        }
641    }
642    ControlFlow::Continue(())
643}
644
645/// Visits the inner types of a type hint.
646pub fn walk_owned_type_hint<V: OwnedVisitor + ?Sized>(
647    visitor: &mut V,
648    type_hint: &TypeHint,
649) -> ControlFlow<()> {
650    match &type_hint.kind {
651        TypeHintKind::Nullable(inner) => {
652            visitor.visit_type_hint(inner)?;
653        }
654        TypeHintKind::Union(types) | TypeHintKind::Intersection(types) => {
655            for ty in types.iter() {
656                visitor.visit_type_hint(ty)?;
657            }
658        }
659        TypeHintKind::Named(name) => {
660            visitor.visit_name(name)?;
661        }
662        TypeHintKind::Keyword(_, _) => {}
663    }
664    ControlFlow::Continue(())
665}
666
667/// Visits an attribute's name and argument expressions.
668pub fn walk_owned_attribute<V: OwnedVisitor + ?Sized>(
669    visitor: &mut V,
670    attribute: &Attribute,
671) -> ControlFlow<()> {
672    visitor.visit_name(&attribute.name)?;
673    for arg in attribute.args.iter() {
674        visitor.visit_arg(arg)?;
675    }
676    ControlFlow::Continue(())
677}
678
679/// Visits a catch clause's type names and body statements.
680pub fn walk_owned_catch_clause<V: OwnedVisitor + ?Sized>(
681    visitor: &mut V,
682    catch: &CatchClause,
683) -> ControlFlow<()> {
684    for ty in catch.types.iter() {
685        visitor.visit_name(ty)?;
686    }
687    visitor.visit_block(&catch.body)?;
688    ControlFlow::Continue(())
689}
690
691/// Visits a match arm's condition expressions and body expression.
692pub fn walk_owned_match_arm<V: OwnedVisitor + ?Sized>(
693    visitor: &mut V,
694    arm: &MatchArm,
695) -> ControlFlow<()> {
696    if let Some(conditions) = &arm.conditions {
697        for cond in conditions.iter() {
698            visitor.visit_expr(cond)?;
699        }
700    }
701    visitor.visit_expr(&arm.body)
702}
703
704/// Visits a trait use declaration's names and adaptations.
705pub fn walk_owned_trait_use<V: OwnedVisitor + ?Sized>(
706    visitor: &mut V,
707    trait_use: &TraitUseDecl,
708) -> ControlFlow<()> {
709    for name in trait_use.traits.iter() {
710        visitor.visit_name(name)?;
711    }
712    for adaptation in trait_use.adaptations.iter() {
713        visitor.visit_trait_adaptation(adaptation)?;
714    }
715    ControlFlow::Continue(())
716}
717
718// =============================================================================
719// Internal helpers
720// =============================================================================
721
722fn walk_owned_function_like<V: OwnedVisitor + ?Sized>(
723    visitor: &mut V,
724    attributes: &[Attribute],
725    params: &[Param],
726    return_type: &Option<TypeHint>,
727) -> ControlFlow<()> {
728    walk_owned_attributes(visitor, attributes)?;
729    for param in params.iter() {
730        visitor.visit_param(param)?;
731    }
732    if let Some(ret) = return_type {
733        visitor.visit_type_hint(ret)?;
734    }
735    ControlFlow::Continue(())
736}
737
738fn walk_owned_method_decl<V: OwnedVisitor + ?Sized>(
739    visitor: &mut V,
740    method: &MethodDecl,
741) -> ControlFlow<()> {
742    walk_owned_function_like(
743        visitor,
744        &method.attributes,
745        &method.params,
746        &method.return_type,
747    )?;
748    if let Some(body) = &method.body {
749        visitor.visit_block(body)?;
750    }
751    ControlFlow::Continue(())
752}
753
754fn walk_owned_class_const_decl<V: OwnedVisitor + ?Sized>(
755    visitor: &mut V,
756    cc: &ClassConstDecl,
757) -> ControlFlow<()> {
758    walk_owned_attributes(visitor, &cc.attributes)?;
759    if let Some(type_hint) = &cc.type_hint {
760        visitor.visit_type_hint(type_hint)?;
761    }
762    visitor.visit_expr(&cc.value)
763}
764
765fn walk_owned_property_decl<V: OwnedVisitor + ?Sized>(
766    visitor: &mut V,
767    prop: &PropertyDecl,
768) -> ControlFlow<()> {
769    walk_owned_attributes(visitor, &prop.attributes)?;
770    if let Some(type_hint) = &prop.type_hint {
771        visitor.visit_type_hint(type_hint)?;
772    }
773    if let Some(default) = &prop.default {
774        visitor.visit_expr(default)?;
775    }
776    for hook in prop.hooks.iter() {
777        visitor.visit_property_hook(hook)?;
778    }
779    ControlFlow::Continue(())
780}
781
782fn walk_owned_attributes<V: OwnedVisitor + ?Sized>(
783    visitor: &mut V,
784    attributes: &[Attribute],
785) -> ControlFlow<()> {
786    for attr in attributes.iter() {
787        visitor.visit_attribute(attr)?;
788    }
789    ControlFlow::Continue(())
790}
791
792// =============================================================================
793// OwnedScopeVisitor — scope-aware traversal
794// =============================================================================
795
796/// Lexical scope context for owned AST traversal.
797///
798/// Like [`crate::visitor::Scope`] but uses `Option<String>` instead of
799/// `Option<&str>` so the owned visitor has no lifetime parameters.
800#[derive(Debug, Clone, Default)]
801pub struct OwnedScope {
802    /// Current namespace, or `None` for the global namespace.
803    pub namespace: Option<String>,
804    /// Name of the immediately enclosing class-like declaration, or `None`.
805    pub class_name: Option<String>,
806    /// Name of the immediately enclosing named function or method, or `None`.
807    pub function_name: Option<String>,
808}
809
810/// A scope-aware variant of [`OwnedVisitor`].
811///
812/// Every visit method receives an [`OwnedScope`] describing the lexical context
813/// at that node. Drive traversal with [`OwnedScopeWalker`].
814pub trait OwnedScopeVisitor {
815    fn visit_program(&mut self, _program: &Program, _scope: &OwnedScope) -> ControlFlow<()> {
816        ControlFlow::Continue(())
817    }
818    fn visit_stmt(&mut self, _stmt: &Stmt, _scope: &OwnedScope) -> ControlFlow<()> {
819        ControlFlow::Continue(())
820    }
821    fn visit_expr(&mut self, _expr: &Expr, _scope: &OwnedScope) -> ControlFlow<()> {
822        ControlFlow::Continue(())
823    }
824    fn visit_param(&mut self, _param: &Param, _scope: &OwnedScope) -> ControlFlow<()> {
825        ControlFlow::Continue(())
826    }
827    fn visit_arg(&mut self, _arg: &Arg, _scope: &OwnedScope) -> ControlFlow<()> {
828        ControlFlow::Continue(())
829    }
830    fn visit_class_member(
831        &mut self,
832        _member: &ClassMember,
833        _scope: &OwnedScope,
834    ) -> ControlFlow<()> {
835        ControlFlow::Continue(())
836    }
837    fn visit_enum_member(&mut self, _member: &EnumMember, _scope: &OwnedScope) -> ControlFlow<()> {
838        ControlFlow::Continue(())
839    }
840    fn visit_property_hook(
841        &mut self,
842        _hook: &PropertyHook,
843        _scope: &OwnedScope,
844    ) -> ControlFlow<()> {
845        ControlFlow::Continue(())
846    }
847    fn visit_type_hint(&mut self, _type_hint: &TypeHint, _scope: &OwnedScope) -> ControlFlow<()> {
848        ControlFlow::Continue(())
849    }
850    fn visit_attribute(&mut self, _attribute: &Attribute, _scope: &OwnedScope) -> ControlFlow<()> {
851        ControlFlow::Continue(())
852    }
853    fn visit_catch_clause(&mut self, _catch: &CatchClause, _scope: &OwnedScope) -> ControlFlow<()> {
854        ControlFlow::Continue(())
855    }
856    fn visit_match_arm(&mut self, _arm: &MatchArm, _scope: &OwnedScope) -> ControlFlow<()> {
857        ControlFlow::Continue(())
858    }
859    fn visit_closure_use_var(
860        &mut self,
861        _var: &ClosureUseVar,
862        _scope: &OwnedScope,
863    ) -> ControlFlow<()> {
864        ControlFlow::Continue(())
865    }
866    fn visit_trait_use(
867        &mut self,
868        _trait_use: &TraitUseDecl,
869        _scope: &OwnedScope,
870    ) -> ControlFlow<()> {
871        ControlFlow::Continue(())
872    }
873    fn visit_trait_adaptation(
874        &mut self,
875        _adaptation: &TraitAdaptation,
876        _scope: &OwnedScope,
877    ) -> ControlFlow<()> {
878        ControlFlow::Continue(())
879    }
880    fn visit_comment(&mut self, _comment: &Comment, _scope: &OwnedScope) -> ControlFlow<()> {
881        ControlFlow::Continue(())
882    }
883}
884
885/// Drives an [`OwnedScopeVisitor`] over an owned AST, maintaining [`OwnedScope`] automatically.
886pub struct OwnedScopeWalker<V> {
887    inner: V,
888    scope: OwnedScope,
889}
890
891impl<V> OwnedScopeWalker<V> {
892    /// Creates a new walker wrapping `inner`.
893    pub fn new(inner: V) -> Self {
894        Self {
895            inner,
896            scope: OwnedScope::default(),
897        }
898    }
899
900    /// Consumes the walker and returns the inner visitor.
901    pub fn into_inner(self) -> V {
902        self.inner
903    }
904
905    /// Returns a reference to the inner visitor.
906    pub fn inner(&self) -> &V {
907        &self.inner
908    }
909
910    /// Returns a mutable reference to the inner visitor.
911    pub fn inner_mut(&mut self) -> &mut V {
912        &mut self.inner
913    }
914}
915
916impl<V: OwnedScopeVisitor> OwnedScopeWalker<V> {
917    /// Walks `program`, calling [`OwnedScopeVisitor`] methods with scope context.
918    pub fn walk(&mut self, program: &Program) -> ControlFlow<()> {
919        self.visit_program(program)
920    }
921}
922
923fn owned_name_repr(name: &Name) -> Option<String> {
924    if name.parts.is_empty() {
925        return None;
926    }
927    Some(
928        name.parts
929            .iter()
930            .map(|s| s.as_ref())
931            .collect::<Vec<_>>()
932            .join("\\"),
933    )
934}
935
936impl<V: OwnedScopeVisitor> OwnedVisitor for OwnedScopeWalker<V> {
937    fn visit_program(&mut self, program: &Program) -> ControlFlow<()> {
938        self.inner.visit_program(program, &self.scope)?;
939        walk_owned_program(self, program)
940    }
941
942    fn visit_stmt(&mut self, stmt: &Stmt) -> ControlFlow<()> {
943        self.inner.visit_stmt(stmt, &self.scope)?;
944        match &stmt.kind {
945            StmtKind::Function(func) => {
946                let fn_name = func.name.as_ref().map(|n| n.to_string());
947                let prev_fn = std::mem::replace(&mut self.scope.function_name, fn_name);
948                walk_owned_stmt(self, stmt)?;
949                self.scope.function_name = prev_fn;
950            }
951            StmtKind::Class(class) => {
952                let class_name = class
953                    .name
954                    .as_ref()
955                    .and_then(|ident| ident.as_ref())
956                    .map(|s| s.to_string());
957                let prev_class = std::mem::replace(&mut self.scope.class_name, class_name);
958                let prev_fn = self.scope.function_name.take();
959                walk_owned_stmt(self, stmt)?;
960                self.scope.class_name = prev_class;
961                self.scope.function_name = prev_fn;
962            }
963            StmtKind::Interface(iface) => {
964                let iface_name = iface.name.as_ref().map(|n| n.to_string());
965                let prev_class = std::mem::replace(&mut self.scope.class_name, iface_name);
966                let prev_fn = self.scope.function_name.take();
967                walk_owned_stmt(self, stmt)?;
968                self.scope.class_name = prev_class;
969                self.scope.function_name = prev_fn;
970            }
971            StmtKind::Trait(trait_decl) => {
972                let trait_name = trait_decl.name.as_ref().map(|n| n.to_string());
973                let prev_class = std::mem::replace(&mut self.scope.class_name, trait_name);
974                let prev_fn = self.scope.function_name.take();
975                walk_owned_stmt(self, stmt)?;
976                self.scope.class_name = prev_class;
977                self.scope.function_name = prev_fn;
978            }
979            StmtKind::Enum(enum_decl) => {
980                let enum_name = enum_decl.name.as_ref().map(|n| n.to_string());
981                let prev_class = std::mem::replace(&mut self.scope.class_name, enum_name);
982                let prev_fn = self.scope.function_name.take();
983                walk_owned_stmt(self, stmt)?;
984                self.scope.class_name = prev_class;
985                self.scope.function_name = prev_fn;
986            }
987            StmtKind::Namespace(ns) => {
988                let ns_str = ns.name.as_ref().and_then(owned_name_repr);
989                match &ns.body {
990                    NamespaceBody::Braced(_) => {
991                        let prev_ns = std::mem::replace(&mut self.scope.namespace, ns_str);
992                        let prev_class = self.scope.class_name.take();
993                        let prev_fn = self.scope.function_name.take();
994                        walk_owned_stmt(self, stmt)?;
995                        self.scope.namespace = prev_ns;
996                        self.scope.class_name = prev_class;
997                        self.scope.function_name = prev_fn;
998                    }
999                    NamespaceBody::Simple => {
1000                        self.scope.namespace = ns_str;
1001                        self.scope.class_name = None;
1002                        self.scope.function_name = None;
1003                    }
1004                }
1005            }
1006            _ => {
1007                walk_owned_stmt(self, stmt)?;
1008            }
1009        }
1010        ControlFlow::Continue(())
1011    }
1012
1013    fn visit_expr(&mut self, expr: &Expr) -> ControlFlow<()> {
1014        self.inner.visit_expr(expr, &self.scope)?;
1015        match &expr.kind {
1016            ExprKind::Closure(_) | ExprKind::ArrowFunction(_) => {
1017                let prev_fn = self.scope.function_name.take();
1018                walk_owned_expr(self, expr)?;
1019                self.scope.function_name = prev_fn;
1020            }
1021            ExprKind::AnonymousClass(_) => {
1022                let prev_class = self.scope.class_name.take();
1023                let prev_fn = self.scope.function_name.take();
1024                walk_owned_expr(self, expr)?;
1025                self.scope.class_name = prev_class;
1026                self.scope.function_name = prev_fn;
1027            }
1028            _ => {
1029                walk_owned_expr(self, expr)?;
1030            }
1031        }
1032        ControlFlow::Continue(())
1033    }
1034
1035    fn visit_class_member(&mut self, member: &ClassMember) -> ControlFlow<()> {
1036        self.inner.visit_class_member(member, &self.scope)?;
1037        if let ClassMemberKind::Method(method) = &member.kind {
1038            let fn_name = method.name.as_ref().map(|n| n.to_string());
1039            let prev_fn = std::mem::replace(&mut self.scope.function_name, fn_name);
1040            walk_owned_class_member(self, member)?;
1041            self.scope.function_name = prev_fn;
1042        } else {
1043            walk_owned_class_member(self, member)?;
1044        }
1045        ControlFlow::Continue(())
1046    }
1047
1048    fn visit_enum_member(&mut self, member: &EnumMember) -> ControlFlow<()> {
1049        self.inner.visit_enum_member(member, &self.scope)?;
1050        if let EnumMemberKind::Method(method) = &member.kind {
1051            let fn_name = method.name.as_ref().map(|n| n.to_string());
1052            let prev_fn = std::mem::replace(&mut self.scope.function_name, fn_name);
1053            walk_owned_enum_member(self, member)?;
1054            self.scope.function_name = prev_fn;
1055        } else {
1056            walk_owned_enum_member(self, member)?;
1057        }
1058        ControlFlow::Continue(())
1059    }
1060
1061    fn visit_param(&mut self, param: &Param) -> ControlFlow<()> {
1062        self.inner.visit_param(param, &self.scope)?;
1063        walk_owned_param(self, param)
1064    }
1065
1066    fn visit_arg(&mut self, arg: &Arg) -> ControlFlow<()> {
1067        self.inner.visit_arg(arg, &self.scope)?;
1068        walk_owned_arg(self, arg)
1069    }
1070
1071    fn visit_property_hook(&mut self, hook: &PropertyHook) -> ControlFlow<()> {
1072        self.inner.visit_property_hook(hook, &self.scope)?;
1073        walk_owned_property_hook(self, hook)
1074    }
1075
1076    fn visit_type_hint(&mut self, type_hint: &TypeHint) -> ControlFlow<()> {
1077        self.inner.visit_type_hint(type_hint, &self.scope)?;
1078        walk_owned_type_hint(self, type_hint)
1079    }
1080
1081    fn visit_attribute(&mut self, attribute: &Attribute) -> ControlFlow<()> {
1082        self.inner.visit_attribute(attribute, &self.scope)?;
1083        walk_owned_attribute(self, attribute)
1084    }
1085
1086    fn visit_catch_clause(&mut self, catch: &CatchClause) -> ControlFlow<()> {
1087        self.inner.visit_catch_clause(catch, &self.scope)?;
1088        walk_owned_catch_clause(self, catch)
1089    }
1090
1091    fn visit_match_arm(&mut self, arm: &MatchArm) -> ControlFlow<()> {
1092        self.inner.visit_match_arm(arm, &self.scope)?;
1093        walk_owned_match_arm(self, arm)
1094    }
1095
1096    fn visit_closure_use_var(&mut self, var: &ClosureUseVar) -> ControlFlow<()> {
1097        self.inner.visit_closure_use_var(var, &self.scope)
1098    }
1099
1100    fn visit_trait_use(&mut self, trait_use: &TraitUseDecl) -> ControlFlow<()> {
1101        self.inner.visit_trait_use(trait_use, &self.scope)?;
1102        walk_owned_trait_use(self, trait_use)
1103    }
1104
1105    fn visit_trait_adaptation(&mut self, adaptation: &TraitAdaptation) -> ControlFlow<()> {
1106        self.inner.visit_trait_adaptation(adaptation, &self.scope)
1107    }
1108
1109    fn visit_comment(&mut self, comment: &Comment) -> ControlFlow<()> {
1110        self.inner.visit_comment(comment, &self.scope)
1111    }
1112}
1113
1114// =============================================================================
1115// Tests
1116// =============================================================================
1117
1118#[cfg(test)]
1119mod tests {
1120    use super::*;
1121    use crate::ast::{AssignOp, BinaryOp};
1122    use crate::Span;
1123
1124    fn dummy_var(name: &str) -> Expr {
1125        Expr {
1126            kind: ExprKind::Variable(Box::from(name)),
1127            span: Span::DUMMY,
1128        }
1129    }
1130
1131    fn dummy_int(n: i64) -> Expr {
1132        Expr {
1133            kind: ExprKind::Int(n),
1134            span: Span::DUMMY,
1135        }
1136    }
1137
1138    fn binary(left: Expr, op: BinaryOp, right: Expr) -> Expr {
1139        Expr {
1140            kind: ExprKind::Binary(BinaryExpr {
1141                left: Box::new(left),
1142                op,
1143                right: Box::new(right),
1144            }),
1145            span: Span::DUMMY,
1146        }
1147    }
1148
1149    fn expr_stmt(e: Expr) -> Stmt {
1150        Stmt {
1151            kind: StmtKind::Expression(Box::new(e)),
1152            span: Span::DUMMY,
1153        }
1154    }
1155
1156    fn block_of(stmts: impl IntoIterator<Item = Stmt>) -> Box<Block> {
1157        Box::new(Block {
1158            stmts: stmts.into_iter().collect(),
1159            span: Span::DUMMY,
1160        })
1161    }
1162
1163    fn program(stmts: impl IntoIterator<Item = Stmt>) -> Program {
1164        Program {
1165            stmts: stmts.into_iter().collect(),
1166            span: Span::DUMMY,
1167        }
1168    }
1169
1170    struct VarCounter {
1171        count: usize,
1172    }
1173
1174    impl OwnedVisitor for VarCounter {
1175        fn visit_expr(&mut self, expr: &Expr) -> ControlFlow<()> {
1176            if matches!(&expr.kind, ExprKind::Variable(_)) {
1177                self.count += 1;
1178            }
1179            walk_owned_expr(self, expr)
1180        }
1181    }
1182
1183    #[test]
1184    fn counts_variables() {
1185        // $x = $y + $z;
1186        let p = program([expr_stmt(Expr {
1187            kind: ExprKind::Assign(AssignExpr {
1188                target: Box::new(dummy_var("x")),
1189                op: AssignOp::Assign,
1190                value: Box::new(binary(dummy_var("y"), BinaryOp::Add, dummy_var("z"))),
1191                by_ref: false,
1192            }),
1193            span: Span::DUMMY,
1194        })]);
1195        let mut v = VarCounter { count: 0 };
1196        let _ = v.visit_program(&p);
1197        assert_eq!(v.count, 3);
1198    }
1199
1200    #[test]
1201    fn early_termination() {
1202        // $a + $b;
1203        let p = program([expr_stmt(binary(
1204            dummy_var("a"),
1205            BinaryOp::Add,
1206            dummy_var("b"),
1207        ))]);
1208
1209        struct FindFirst {
1210            found: Option<String>,
1211        }
1212        impl OwnedVisitor for FindFirst {
1213            fn visit_expr(&mut self, expr: &Expr) -> ControlFlow<()> {
1214                if let ExprKind::Variable(name) = &expr.kind {
1215                    self.found = Some(name.to_string());
1216                    return ControlFlow::Break(());
1217                }
1218                walk_owned_expr(self, expr)
1219            }
1220        }
1221
1222        let mut finder = FindFirst { found: None };
1223        let r = finder.visit_program(&p);
1224        assert!(r.is_break());
1225        assert_eq!(finder.found.as_deref(), Some("a"));
1226    }
1227
1228    #[test]
1229    fn skip_subtree() {
1230        // 1 + 2; function foo() { 3 + 4; }
1231        let top = binary(dummy_int(1), BinaryOp::Add, dummy_int(2));
1232        let inner = binary(dummy_int(3), BinaryOp::Add, dummy_int(4));
1233        let func = Stmt {
1234            kind: StmtKind::Function(Box::new(FunctionDecl {
1235                name: Some(Box::from("foo")),
1236                params: Box::from([]),
1237                body: block_of([expr_stmt(inner)]),
1238                return_type: None,
1239                by_ref: false,
1240                attributes: Box::from([]),
1241                doc_comment: None,
1242            })),
1243            span: Span::DUMMY,
1244        };
1245        let p = program([expr_stmt(top), func]);
1246
1247        struct SkipFunctions {
1248            expr_count: usize,
1249        }
1250        impl OwnedVisitor for SkipFunctions {
1251            fn visit_expr(&mut self, expr: &Expr) -> ControlFlow<()> {
1252                self.expr_count += 1;
1253                walk_owned_expr(self, expr)
1254            }
1255            fn visit_stmt(&mut self, stmt: &Stmt) -> ControlFlow<()> {
1256                if matches!(&stmt.kind, StmtKind::Function(_)) {
1257                    return ControlFlow::Continue(());
1258                }
1259                walk_owned_stmt(self, stmt)
1260            }
1261        }
1262
1263        let mut v = SkipFunctions { expr_count: 0 };
1264        let _ = v.visit_program(&p);
1265        // Only top-level: binary(1, 2) = 3 exprs
1266        assert_eq!(v.expr_count, 3);
1267    }
1268
1269    #[test]
1270    fn scope_walker_tracks_class_and_method() {
1271        // class Foo { public function bar() { $x; } }
1272        let method = ClassMember {
1273            kind: ClassMemberKind::Method(MethodDecl {
1274                name: Some(Box::from("bar")),
1275                visibility: Some(crate::ast::Visibility::Public),
1276                is_static: false,
1277                is_abstract: false,
1278                is_final: false,
1279                by_ref: false,
1280                params: Box::from([]),
1281                return_type: None,
1282                body: Some(block_of([expr_stmt(dummy_var("x"))])),
1283                attributes: Box::from([]),
1284                doc_comment: None,
1285            }),
1286            span: Span::DUMMY,
1287        };
1288        let class_stmt = Stmt {
1289            kind: StmtKind::Class(Box::new(ClassDecl {
1290                name: Some(Some(Box::from("Foo"))),
1291                modifiers: crate::ast::ClassModifiers::default(),
1292                extends: None,
1293                implements: Box::from([]),
1294                body: ClassBody {
1295                    members: [method].into_iter().collect(),
1296                    span: Span::DUMMY,
1297                },
1298                attributes: Box::from([]),
1299                doc_comment: None,
1300            })),
1301            span: Span::DUMMY,
1302        };
1303        let p = program([class_stmt]);
1304
1305        struct MethodCollector {
1306            methods: Vec<String>,
1307        }
1308        impl OwnedScopeVisitor for MethodCollector {
1309            fn visit_class_member(
1310                &mut self,
1311                member: &ClassMember,
1312                scope: &OwnedScope,
1313            ) -> ControlFlow<()> {
1314                if let ClassMemberKind::Method(m) = &member.kind {
1315                    self.methods.push(format!(
1316                        "{}::{}",
1317                        scope.class_name.as_deref().unwrap_or("<anon>"),
1318                        m.name.as_deref().unwrap_or("<error>"),
1319                    ));
1320                }
1321                ControlFlow::Continue(())
1322            }
1323        }
1324
1325        let mut walker = OwnedScopeWalker::new(MethodCollector { methods: vec![] });
1326        let _ = walker.walk(&p);
1327        assert_eq!(walker.into_inner().methods, ["Foo::bar"]);
1328    }
1329}
php_ast/owned/visitor.rs

php_ast/owned/
visitor.rs
