ra_ap_hir_expand/
lib.rs

1//! `hir_expand` deals with macro expansion.
2//!
3//! Specifically, it implements a concept of `MacroFile` -- a file whose syntax
4//! tree originates not from the text of some `FileId`, but from some macro
5//! expansion.
6#![cfg_attr(feature = "in-rust-tree", feature(rustc_private))]
7
8pub use intern;
9
10pub mod attrs;
11pub mod builtin;
12pub mod change;
13pub mod db;
14pub mod declarative;
15pub mod eager;
16pub mod files;
17pub mod hygiene;
18pub mod inert_attr_macro;
19pub mod mod_path;
20pub mod name;
21pub mod proc_macro;
22pub mod span_map;
23
24mod cfg_process;
25mod fixup;
26mod prettify_macro_expansion_;
27
28use attrs::collect_attrs;
29use rustc_hash::FxHashMap;
30use salsa::plumbing::{AsId, FromId};
31use stdx::TupleExt;
32use triomphe::Arc;
33
34use core::fmt;
35use std::hash::Hash;
36
37use base_db::Crate;
38use either::Either;
39use span::{Edition, ErasedFileAstId, FileAstId, Span, SpanAnchor, SyntaxContext};
40use syntax::{
41    SyntaxNode, SyntaxToken, TextRange, TextSize,
42    ast::{self, AstNode},
43};
44
45use crate::{
46    attrs::AttrId,
47    builtin::{
48        BuiltinAttrExpander, BuiltinDeriveExpander, BuiltinFnLikeExpander, EagerExpander,
49        include_input_to_file_id,
50    },
51    db::ExpandDatabase,
52    mod_path::ModPath,
53    proc_macro::{CustomProcMacroExpander, ProcMacroKind},
54    span_map::{ExpansionSpanMap, SpanMap},
55};
56
57pub use crate::{
58    cfg_process::check_cfg_attr_value,
59    files::{AstId, ErasedAstId, FileRange, InFile, InMacroFile, InRealFile},
60    prettify_macro_expansion_::prettify_macro_expansion,
61};
62
63pub use base_db::EditionedFileId;
64pub use mbe::{DeclarativeMacro, ValueResult};
65
66pub mod tt {
67    pub use span::Span;
68    pub use tt::{DelimiterKind, IdentIsRaw, LitKind, Spacing, token_to_literal};
69
70    pub type Delimiter = ::tt::Delimiter<Span>;
71    pub type DelimSpan = ::tt::DelimSpan<Span>;
72    pub type Subtree = ::tt::Subtree<Span>;
73    pub type Leaf = ::tt::Leaf<Span>;
74    pub type Literal = ::tt::Literal<Span>;
75    pub type Punct = ::tt::Punct<Span>;
76    pub type Ident = ::tt::Ident<Span>;
77    pub type TokenTree = ::tt::TokenTree<Span>;
78    pub type TopSubtree = ::tt::TopSubtree<Span>;
79    pub type TopSubtreeBuilder = ::tt::TopSubtreeBuilder<Span>;
80    pub type TokenTreesView<'a> = ::tt::TokenTreesView<'a, Span>;
81    pub type SubtreeView<'a> = ::tt::SubtreeView<'a, Span>;
82    pub type TtElement<'a> = ::tt::iter::TtElement<'a, Span>;
83    pub type TtIter<'a> = ::tt::iter::TtIter<'a, Span>;
84}
85
86#[macro_export]
87macro_rules! impl_intern_lookup {
88    ($db:ident, $id:ident, $loc:ident, $intern:ident, $lookup:ident) => {
89        impl $crate::Intern for $loc {
90            type Database = dyn $db;
91            type ID = $id;
92            fn intern(self, db: &Self::Database) -> Self::ID {
93                db.$intern(self)
94            }
95        }
96
97        impl $crate::Lookup for $id {
98            type Database = dyn $db;
99            type Data = $loc;
100            fn lookup(&self, db: &Self::Database) -> Self::Data {
101                db.$lookup(*self)
102            }
103        }
104    };
105}
106
107// ideally these would be defined in base-db, but the orphan rule doesn't let us
108pub trait Intern {
109    type Database: ?Sized;
110    type ID;
111    fn intern(self, db: &Self::Database) -> Self::ID;
112}
113
114pub trait Lookup {
115    type Database: ?Sized;
116    type Data;
117    fn lookup(&self, db: &Self::Database) -> Self::Data;
118}
119
120impl_intern_lookup!(
121    ExpandDatabase,
122    MacroCallId,
123    MacroCallLoc,
124    intern_macro_call,
125    lookup_intern_macro_call
126);
127
128pub type ExpandResult<T> = ValueResult<T, ExpandError>;
129
130#[derive(Debug, PartialEq, Eq, Clone, Hash)]
131pub struct ExpandError {
132    inner: Arc<(ExpandErrorKind, Span)>,
133}
134
135impl ExpandError {
136    pub fn new(span: Span, kind: ExpandErrorKind) -> Self {
137        ExpandError { inner: Arc::new((kind, span)) }
138    }
139    pub fn other(span: Span, msg: impl Into<Box<str>>) -> Self {
140        ExpandError { inner: Arc::new((ExpandErrorKind::Other(msg.into()), span)) }
141    }
142    pub fn kind(&self) -> &ExpandErrorKind {
143        &self.inner.0
144    }
145    pub fn span(&self) -> Span {
146        self.inner.1
147    }
148
149    pub fn render_to_string(&self, db: &dyn ExpandDatabase) -> RenderedExpandError {
150        self.inner.0.render_to_string(db)
151    }
152}
153
154#[derive(Debug, PartialEq, Eq, Clone, Hash)]
155pub enum ExpandErrorKind {
156    /// Attribute macro expansion is disabled.
157    ProcMacroAttrExpansionDisabled,
158    MissingProcMacroExpander(Crate),
159    /// The macro for this call is disabled.
160    MacroDisabled,
161    /// The macro definition has errors.
162    MacroDefinition,
163    Mbe(mbe::ExpandErrorKind),
164    RecursionOverflow,
165    Other(Box<str>),
166    ProcMacroPanic(Box<str>),
167}
168
169pub struct RenderedExpandError {
170    pub message: String,
171    pub error: bool,
172    pub kind: &'static str,
173}
174
175impl fmt::Display for RenderedExpandError {
176    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
177        write!(f, "{}", self.message)
178    }
179}
180
181impl RenderedExpandError {
182    const GENERAL_KIND: &str = "macro-error";
183    const DISABLED: &str = "proc-macro-disabled";
184    const ATTR_EXP_DISABLED: &str = "attribute-expansion-disabled";
185}
186
187impl ExpandErrorKind {
188    pub fn render_to_string(&self, db: &dyn ExpandDatabase) -> RenderedExpandError {
189        match self {
190            ExpandErrorKind::ProcMacroAttrExpansionDisabled => RenderedExpandError {
191                message: "procedural attribute macro expansion is disabled".to_owned(),
192                error: false,
193                kind: RenderedExpandError::ATTR_EXP_DISABLED,
194            },
195            ExpandErrorKind::MacroDisabled => RenderedExpandError {
196                message: "proc-macro is explicitly disabled".to_owned(),
197                error: false,
198                kind: RenderedExpandError::DISABLED,
199            },
200            &ExpandErrorKind::MissingProcMacroExpander(def_crate) => {
201                match db.proc_macros_for_crate(def_crate).as_ref().and_then(|it| it.get_error()) {
202                    Some((e, hard_err)) => RenderedExpandError {
203                        message: e.to_owned(),
204                        error: hard_err,
205                        kind: RenderedExpandError::GENERAL_KIND,
206                    },
207                    None => RenderedExpandError {
208                        message: format!(
209                            "internal error: proc-macro map is missing error entry for crate {def_crate:?}"
210                        ),
211                        error: true,
212                        kind: RenderedExpandError::GENERAL_KIND,
213                    },
214                }
215            }
216            ExpandErrorKind::MacroDefinition => RenderedExpandError {
217                message: "macro definition has parse errors".to_owned(),
218                error: true,
219                kind: RenderedExpandError::GENERAL_KIND,
220            },
221            ExpandErrorKind::Mbe(e) => RenderedExpandError {
222                message: e.to_string(),
223                error: true,
224                kind: RenderedExpandError::GENERAL_KIND,
225            },
226            ExpandErrorKind::RecursionOverflow => RenderedExpandError {
227                message: "overflow expanding the original macro".to_owned(),
228                error: true,
229                kind: RenderedExpandError::GENERAL_KIND,
230            },
231            ExpandErrorKind::Other(e) => RenderedExpandError {
232                message: (**e).to_owned(),
233                error: true,
234                kind: RenderedExpandError::GENERAL_KIND,
235            },
236            ExpandErrorKind::ProcMacroPanic(e) => RenderedExpandError {
237                message: format!("proc-macro panicked: {e}"),
238                error: true,
239                kind: RenderedExpandError::GENERAL_KIND,
240            },
241        }
242    }
243}
244
245impl From<mbe::ExpandError> for ExpandError {
246    fn from(mbe: mbe::ExpandError) -> Self {
247        ExpandError { inner: Arc::new((ExpandErrorKind::Mbe(mbe.inner.1.clone()), mbe.inner.0)) }
248    }
249}
250#[derive(Debug, Clone, PartialEq, Eq, Hash)]
251pub struct MacroCallLoc {
252    pub def: MacroDefId,
253    pub krate: Crate,
254    pub kind: MacroCallKind,
255    pub ctxt: SyntaxContext,
256}
257
258#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
259pub struct MacroDefId {
260    pub krate: Crate,
261    pub edition: Edition,
262    pub kind: MacroDefKind,
263    pub local_inner: bool,
264    pub allow_internal_unsafe: bool,
265}
266
267#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
268pub enum MacroDefKind {
269    Declarative(AstId<ast::Macro>),
270    BuiltIn(AstId<ast::Macro>, BuiltinFnLikeExpander),
271    BuiltInAttr(AstId<ast::Macro>, BuiltinAttrExpander),
272    BuiltInDerive(AstId<ast::Macro>, BuiltinDeriveExpander),
273    BuiltInEager(AstId<ast::Macro>, EagerExpander),
274    ProcMacro(AstId<ast::Fn>, CustomProcMacroExpander, ProcMacroKind),
275}
276
277impl MacroDefKind {
278    #[inline]
279    pub fn is_declarative(&self) -> bool {
280        matches!(self, MacroDefKind::Declarative(..))
281    }
282
283    pub fn erased_ast_id(&self) -> ErasedAstId {
284        match *self {
285            MacroDefKind::ProcMacro(id, ..) => id.erase(),
286            MacroDefKind::BuiltIn(id, _)
287            | MacroDefKind::BuiltInAttr(id, _)
288            | MacroDefKind::BuiltInDerive(id, _)
289            | MacroDefKind::BuiltInEager(id, _)
290            | MacroDefKind::Declarative(id, ..) => id.erase(),
291        }
292    }
293}
294
295#[derive(Debug, Clone, PartialEq, Eq, Hash)]
296pub struct EagerCallInfo {
297    /// The expanded argument of the eager macro.
298    arg: Arc<tt::TopSubtree>,
299    /// Call id of the eager macro's input file (this is the macro file for its fully expanded input).
300    arg_id: MacroCallId,
301    error: Option<ExpandError>,
302    /// The call site span of the eager macro
303    span: Span,
304}
305
306#[derive(Debug, Clone, PartialEq, Eq, Hash)]
307pub enum MacroCallKind {
308    FnLike {
309        ast_id: AstId<ast::MacroCall>,
310        expand_to: ExpandTo,
311        /// Some if this is a macro call for an eager macro. Note that this is `None`
312        /// for the eager input macro file.
313        // FIXME: This is being interned, subtrees can vary quickly differing just slightly causing
314        // leakage problems here
315        eager: Option<Arc<EagerCallInfo>>,
316    },
317    Derive {
318        ast_id: AstId<ast::Adt>,
319        /// Syntactical index of the invoking `#[derive]` attribute.
320        ///
321        /// Outer attributes are counted first, then inner attributes. This does not support
322        /// out-of-line modules, which may have attributes spread across 2 files!
323        derive_attr_index: AttrId,
324        /// Index of the derive macro in the derive attribute
325        derive_index: u32,
326        /// The "parent" macro call.
327        /// We will resolve the same token tree for all derive macros in the same derive attribute.
328        derive_macro_id: MacroCallId,
329    },
330    Attr {
331        ast_id: AstId<ast::Item>,
332        // FIXME: This shouldn't be here, we can derive this from `invoc_attr_index`
333        // but we need to fix the `cfg_attr` handling first.
334        attr_args: Option<Arc<tt::TopSubtree>>,
335        /// Syntactical index of the invoking `#[attribute]`.
336        ///
337        /// Outer attributes are counted first, then inner attributes. This does not support
338        /// out-of-line modules, which may have attributes spread across 2 files!
339        invoc_attr_index: AttrId,
340    },
341}
342
343impl HirFileId {
344    pub fn edition(self, db: &dyn ExpandDatabase) -> Edition {
345        match self {
346            HirFileId::FileId(file_id) => file_id.editioned_file_id(db).edition(),
347            HirFileId::MacroFile(m) => db.lookup_intern_macro_call(m).def.edition,
348        }
349    }
350    pub fn original_file(self, db: &dyn ExpandDatabase) -> EditionedFileId {
351        let mut file_id = self;
352        loop {
353            match file_id {
354                HirFileId::FileId(id) => break id,
355                HirFileId::MacroFile(macro_call_id) => {
356                    file_id = db.lookup_intern_macro_call(macro_call_id).kind.file_id()
357                }
358            }
359        }
360    }
361
362    pub fn original_file_respecting_includes(mut self, db: &dyn ExpandDatabase) -> EditionedFileId {
363        loop {
364            match self {
365                HirFileId::FileId(id) => break id,
366                HirFileId::MacroFile(file) => {
367                    let loc = db.lookup_intern_macro_call(file);
368                    if loc.def.is_include() {
369                        if let MacroCallKind::FnLike { eager: Some(eager), .. } = &loc.kind {
370                            if let Ok(it) = include_input_to_file_id(db, file, &eager.arg) {
371                                break it;
372                            }
373                        }
374                    }
375                    self = loc.kind.file_id();
376                }
377            }
378        }
379    }
380
381    pub fn original_call_node(self, db: &dyn ExpandDatabase) -> Option<InRealFile<SyntaxNode>> {
382        let mut call = db.lookup_intern_macro_call(self.macro_file()?).to_node(db);
383        loop {
384            match call.file_id {
385                HirFileId::FileId(file_id) => {
386                    break Some(InRealFile { file_id, value: call.value });
387                }
388                HirFileId::MacroFile(macro_call_id) => {
389                    call = db.lookup_intern_macro_call(macro_call_id).to_node(db);
390                }
391            }
392        }
393    }
394
395    pub fn as_builtin_derive_attr_node(
396        &self,
397        db: &dyn ExpandDatabase,
398    ) -> Option<InFile<ast::Attr>> {
399        let macro_file = self.macro_file()?;
400        let loc = db.lookup_intern_macro_call(macro_file);
401        let attr = match loc.def.kind {
402            MacroDefKind::BuiltInDerive(..) => loc.to_node(db),
403            _ => return None,
404        };
405        Some(attr.with_value(ast::Attr::cast(attr.value.clone())?))
406    }
407}
408
409#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
410pub enum MacroKind {
411    /// `macro_rules!` or Macros 2.0 macro.
412    Declarative,
413    /// A built-in function-like macro.
414    DeclarativeBuiltIn,
415    /// A custom derive.
416    Derive,
417    /// A builtin-in derive.
418    DeriveBuiltIn,
419    /// A procedural attribute macro.
420    Attr,
421    /// A built-in attribute macro.
422    AttrBuiltIn,
423    /// A function-like procedural macro.
424    ProcMacro,
425}
426
427impl MacroCallId {
428    pub fn call_node(self, db: &dyn ExpandDatabase) -> InFile<SyntaxNode> {
429        db.lookup_intern_macro_call(self).to_node(db)
430    }
431    pub fn expansion_level(self, db: &dyn ExpandDatabase) -> u32 {
432        let mut level = 0;
433        let mut macro_file = self;
434        loop {
435            let loc = db.lookup_intern_macro_call(macro_file);
436
437            level += 1;
438            macro_file = match loc.kind.file_id() {
439                HirFileId::FileId(_) => break level,
440                HirFileId::MacroFile(it) => it,
441            };
442        }
443    }
444    pub fn parent(self, db: &dyn ExpandDatabase) -> HirFileId {
445        db.lookup_intern_macro_call(self).kind.file_id()
446    }
447
448    /// Return expansion information if it is a macro-expansion file
449    pub fn expansion_info(self, db: &dyn ExpandDatabase) -> ExpansionInfo {
450        ExpansionInfo::new(db, self)
451    }
452
453    pub fn kind(self, db: &dyn ExpandDatabase) -> MacroKind {
454        match db.lookup_intern_macro_call(self).def.kind {
455            MacroDefKind::Declarative(..) => MacroKind::Declarative,
456            MacroDefKind::BuiltIn(..) | MacroDefKind::BuiltInEager(..) => {
457                MacroKind::DeclarativeBuiltIn
458            }
459            MacroDefKind::BuiltInDerive(..) => MacroKind::DeriveBuiltIn,
460            MacroDefKind::ProcMacro(_, _, ProcMacroKind::CustomDerive) => MacroKind::Derive,
461            MacroDefKind::ProcMacro(_, _, ProcMacroKind::Attr) => MacroKind::Attr,
462            MacroDefKind::ProcMacro(_, _, ProcMacroKind::Bang) => MacroKind::ProcMacro,
463            MacroDefKind::BuiltInAttr(..) => MacroKind::AttrBuiltIn,
464        }
465    }
466
467    pub fn is_include_macro(self, db: &dyn ExpandDatabase) -> bool {
468        db.lookup_intern_macro_call(self).def.is_include()
469    }
470
471    pub fn is_include_like_macro(self, db: &dyn ExpandDatabase) -> bool {
472        db.lookup_intern_macro_call(self).def.is_include_like()
473    }
474
475    pub fn is_env_or_option_env(self, db: &dyn ExpandDatabase) -> bool {
476        db.lookup_intern_macro_call(self).def.is_env_or_option_env()
477    }
478
479    pub fn is_eager(self, db: &dyn ExpandDatabase) -> bool {
480        let loc = db.lookup_intern_macro_call(self);
481        matches!(loc.def.kind, MacroDefKind::BuiltInEager(..))
482    }
483
484    pub fn eager_arg(self, db: &dyn ExpandDatabase) -> Option<MacroCallId> {
485        let loc = db.lookup_intern_macro_call(self);
486        match &loc.kind {
487            MacroCallKind::FnLike { eager, .. } => eager.as_ref().map(|it| it.arg_id),
488            _ => None,
489        }
490    }
491
492    pub fn is_derive_attr_pseudo_expansion(self, db: &dyn ExpandDatabase) -> bool {
493        let loc = db.lookup_intern_macro_call(self);
494        loc.def.is_attribute_derive()
495    }
496}
497
498impl MacroDefId {
499    pub fn make_call(
500        self,
501        db: &dyn ExpandDatabase,
502        krate: Crate,
503        kind: MacroCallKind,
504        ctxt: SyntaxContext,
505    ) -> MacroCallId {
506        db.intern_macro_call(MacroCallLoc { def: self, krate, kind, ctxt })
507    }
508
509    pub fn definition_range(&self, db: &dyn ExpandDatabase) -> InFile<TextRange> {
510        match self.kind {
511            MacroDefKind::Declarative(id)
512            | MacroDefKind::BuiltIn(id, _)
513            | MacroDefKind::BuiltInAttr(id, _)
514            | MacroDefKind::BuiltInDerive(id, _)
515            | MacroDefKind::BuiltInEager(id, _) => {
516                id.with_value(db.ast_id_map(id.file_id).get(id.value).text_range())
517            }
518            MacroDefKind::ProcMacro(id, _, _) => {
519                id.with_value(db.ast_id_map(id.file_id).get(id.value).text_range())
520            }
521        }
522    }
523
524    pub fn ast_id(&self) -> Either<AstId<ast::Macro>, AstId<ast::Fn>> {
525        match self.kind {
526            MacroDefKind::ProcMacro(id, ..) => Either::Right(id),
527            MacroDefKind::Declarative(id)
528            | MacroDefKind::BuiltIn(id, _)
529            | MacroDefKind::BuiltInAttr(id, _)
530            | MacroDefKind::BuiltInDerive(id, _)
531            | MacroDefKind::BuiltInEager(id, _) => Either::Left(id),
532        }
533    }
534
535    pub fn is_proc_macro(&self) -> bool {
536        matches!(self.kind, MacroDefKind::ProcMacro(..))
537    }
538
539    pub fn is_attribute(&self) -> bool {
540        matches!(
541            self.kind,
542            MacroDefKind::BuiltInAttr(..) | MacroDefKind::ProcMacro(_, _, ProcMacroKind::Attr)
543        )
544    }
545
546    pub fn is_derive(&self) -> bool {
547        matches!(
548            self.kind,
549            MacroDefKind::BuiltInDerive(..)
550                | MacroDefKind::ProcMacro(_, _, ProcMacroKind::CustomDerive)
551        )
552    }
553
554    pub fn is_fn_like(&self) -> bool {
555        matches!(
556            self.kind,
557            MacroDefKind::BuiltIn(..)
558                | MacroDefKind::ProcMacro(_, _, ProcMacroKind::Bang)
559                | MacroDefKind::BuiltInEager(..)
560                | MacroDefKind::Declarative(..)
561        )
562    }
563
564    pub fn is_attribute_derive(&self) -> bool {
565        matches!(self.kind, MacroDefKind::BuiltInAttr(_, expander) if expander.is_derive())
566    }
567
568    pub fn is_include(&self) -> bool {
569        matches!(self.kind, MacroDefKind::BuiltInEager(_, expander) if expander.is_include())
570    }
571
572    pub fn is_include_like(&self) -> bool {
573        matches!(self.kind, MacroDefKind::BuiltInEager(_, expander) if expander.is_include_like())
574    }
575
576    pub fn is_env_or_option_env(&self) -> bool {
577        matches!(self.kind, MacroDefKind::BuiltInEager(_, expander) if expander.is_env_or_option_env())
578    }
579}
580
581impl MacroCallLoc {
582    pub fn to_node(&self, db: &dyn ExpandDatabase) -> InFile<SyntaxNode> {
583        match self.kind {
584            MacroCallKind::FnLike { ast_id, .. } => {
585                ast_id.with_value(ast_id.to_node(db).syntax().clone())
586            }
587            MacroCallKind::Derive { ast_id, derive_attr_index, .. } => {
588                // FIXME: handle `cfg_attr`
589                ast_id.with_value(ast_id.to_node(db)).map(|it| {
590                    collect_attrs(&it)
591                        .nth(derive_attr_index.ast_index())
592                        .and_then(|it| match it.1 {
593                            Either::Left(attr) => Some(attr.syntax().clone()),
594                            Either::Right(_) => None,
595                        })
596                        .unwrap_or_else(|| it.syntax().clone())
597                })
598            }
599            MacroCallKind::Attr { ast_id, invoc_attr_index, .. } => {
600                if self.def.is_attribute_derive() {
601                    // FIXME: handle `cfg_attr`
602                    ast_id.with_value(ast_id.to_node(db)).map(|it| {
603                        collect_attrs(&it)
604                            .nth(invoc_attr_index.ast_index())
605                            .and_then(|it| match it.1 {
606                                Either::Left(attr) => Some(attr.syntax().clone()),
607                                Either::Right(_) => None,
608                            })
609                            .unwrap_or_else(|| it.syntax().clone())
610                    })
611                } else {
612                    ast_id.with_value(ast_id.to_node(db).syntax().clone())
613                }
614            }
615        }
616    }
617
618    pub fn to_node_item(&self, db: &dyn ExpandDatabase) -> InFile<ast::Item> {
619        match self.kind {
620            MacroCallKind::FnLike { ast_id, .. } => {
621                InFile::new(ast_id.file_id, ast_id.map(FileAstId::upcast).to_node(db))
622            }
623            MacroCallKind::Derive { ast_id, .. } => {
624                InFile::new(ast_id.file_id, ast_id.map(FileAstId::upcast).to_node(db))
625            }
626            MacroCallKind::Attr { ast_id, .. } => InFile::new(ast_id.file_id, ast_id.to_node(db)),
627        }
628    }
629
630    fn expand_to(&self) -> ExpandTo {
631        match self.kind {
632            MacroCallKind::FnLike { expand_to, .. } => expand_to,
633            MacroCallKind::Derive { .. } => ExpandTo::Items,
634            MacroCallKind::Attr { .. } if self.def.is_attribute_derive() => ExpandTo::Items,
635            MacroCallKind::Attr { .. } => {
636                // FIXME(stmt_expr_attributes)
637                ExpandTo::Items
638            }
639        }
640    }
641
642    pub fn include_file_id(
643        &self,
644        db: &dyn ExpandDatabase,
645        macro_call_id: MacroCallId,
646    ) -> Option<EditionedFileId> {
647        if self.def.is_include() {
648            if let MacroCallKind::FnLike { eager: Some(eager), .. } = &self.kind {
649                if let Ok(it) = include_input_to_file_id(db, macro_call_id, &eager.arg) {
650                    return Some(it);
651                }
652            }
653        }
654
655        None
656    }
657}
658
659impl MacroCallKind {
660    pub fn descr(&self) -> &'static str {
661        match self {
662            MacroCallKind::FnLike { .. } => "macro call",
663            MacroCallKind::Derive { .. } => "derive macro",
664            MacroCallKind::Attr { .. } => "attribute macro",
665        }
666    }
667
668    /// Returns the file containing the macro invocation.
669    pub fn file_id(&self) -> HirFileId {
670        match *self {
671            MacroCallKind::FnLike { ast_id: InFile { file_id, .. }, .. }
672            | MacroCallKind::Derive { ast_id: InFile { file_id, .. }, .. }
673            | MacroCallKind::Attr { ast_id: InFile { file_id, .. }, .. } => file_id,
674        }
675    }
676
677    pub fn erased_ast_id(&self) -> ErasedFileAstId {
678        match *self {
679            MacroCallKind::FnLike { ast_id: InFile { value, .. }, .. } => value.erase(),
680            MacroCallKind::Derive { ast_id: InFile { value, .. }, .. } => value.erase(),
681            MacroCallKind::Attr { ast_id: InFile { value, .. }, .. } => value.erase(),
682        }
683    }
684
685    /// Returns the original file range that best describes the location of this macro call.
686    ///
687    /// Unlike `MacroCallKind::original_call_range`, this also spans the item of attributes and derives.
688    pub fn original_call_range_with_body(self, db: &dyn ExpandDatabase) -> FileRange {
689        let mut kind = self;
690        let file_id = loop {
691            match kind.file_id() {
692                HirFileId::MacroFile(file) => {
693                    kind = db.lookup_intern_macro_call(file).kind;
694                }
695                HirFileId::FileId(file_id) => break file_id,
696            }
697        };
698
699        let range = match kind {
700            MacroCallKind::FnLike { ast_id, .. } => ast_id.to_ptr(db).text_range(),
701            MacroCallKind::Derive { ast_id, .. } => ast_id.to_ptr(db).text_range(),
702            MacroCallKind::Attr { ast_id, .. } => ast_id.to_ptr(db).text_range(),
703        };
704
705        FileRange { range, file_id }
706    }
707
708    /// Returns the original file range that best describes the location of this macro call.
709    ///
710    /// Here we try to roughly match what rustc does to improve diagnostics: fn-like macros
711    /// get the whole `ast::MacroCall`, attribute macros get the attribute's range, and derives
712    /// get only the specific derive that is being referred to.
713    pub fn original_call_range(self, db: &dyn ExpandDatabase) -> FileRange {
714        let mut kind = self;
715        let file_id = loop {
716            match kind.file_id() {
717                HirFileId::MacroFile(file) => {
718                    kind = db.lookup_intern_macro_call(file).kind;
719                }
720                HirFileId::FileId(file_id) => break file_id,
721            }
722        };
723
724        let range = match kind {
725            MacroCallKind::FnLike { ast_id, .. } => ast_id.to_ptr(db).text_range(),
726            MacroCallKind::Derive { ast_id, derive_attr_index, .. } => {
727                // FIXME: should be the range of the macro name, not the whole derive
728                // FIXME: handle `cfg_attr`
729                collect_attrs(&ast_id.to_node(db))
730                    .nth(derive_attr_index.ast_index())
731                    .expect("missing derive")
732                    .1
733                    .expect_left("derive is a doc comment?")
734                    .syntax()
735                    .text_range()
736            }
737            // FIXME: handle `cfg_attr`
738            MacroCallKind::Attr { ast_id, invoc_attr_index, .. } => {
739                collect_attrs(&ast_id.to_node(db))
740                    .nth(invoc_attr_index.ast_index())
741                    .expect("missing attribute")
742                    .1
743                    .expect_left("attribute macro is a doc comment?")
744                    .syntax()
745                    .text_range()
746            }
747        };
748
749        FileRange { range, file_id }
750    }
751
752    fn arg(&self, db: &dyn ExpandDatabase) -> InFile<Option<SyntaxNode>> {
753        match self {
754            MacroCallKind::FnLike { ast_id, .. } => {
755                ast_id.to_in_file_node(db).map(|it| Some(it.token_tree()?.syntax().clone()))
756            }
757            MacroCallKind::Derive { ast_id, .. } => {
758                ast_id.to_in_file_node(db).syntax().cloned().map(Some)
759            }
760            MacroCallKind::Attr { ast_id, .. } => {
761                ast_id.to_in_file_node(db).syntax().cloned().map(Some)
762            }
763        }
764    }
765}
766
767/// ExpansionInfo mainly describes how to map text range between src and expanded macro
768// FIXME: can be expensive to create, we should check the use sites and maybe replace them with
769// simpler function calls if the map is only used once
770#[derive(Clone, Debug, PartialEq, Eq)]
771pub struct ExpansionInfo {
772    expanded: InMacroFile<SyntaxNode>,
773    /// The argument TokenTree or item for attributes
774    arg: InFile<Option<SyntaxNode>>,
775    exp_map: Arc<ExpansionSpanMap>,
776    arg_map: SpanMap,
777    loc: MacroCallLoc,
778}
779
780impl ExpansionInfo {
781    pub fn expanded(&self) -> InMacroFile<SyntaxNode> {
782        self.expanded.clone()
783    }
784
785    pub fn arg(&self) -> InFile<Option<&SyntaxNode>> {
786        self.arg.as_ref().map(|it| it.as_ref())
787    }
788
789    pub fn call_file(&self) -> HirFileId {
790        self.arg.file_id
791    }
792
793    pub fn is_attr(&self) -> bool {
794        matches!(
795            self.loc.def.kind,
796            MacroDefKind::BuiltInAttr(..) | MacroDefKind::ProcMacro(_, _, ProcMacroKind::Attr)
797        )
798    }
799
800    /// Maps the passed in file range down into a macro expansion if it is the input to a macro call.
801    ///
802    /// Note this does a linear search through the entire backing vector of the spanmap.
803    // FIXME: Consider adding a reverse map to ExpansionInfo to get rid of the linear search which
804    // potentially results in quadratic look ups (notably this might improve semantic highlighting perf)
805    pub fn map_range_down_exact(
806        &self,
807        span: Span,
808    ) -> Option<InMacroFile<impl Iterator<Item = (SyntaxToken, SyntaxContext)> + '_>> {
809        let tokens = self.exp_map.ranges_with_span_exact(span).flat_map(move |(range, ctx)| {
810            self.expanded.value.covering_element(range).into_token().zip(Some(ctx))
811        });
812
813        Some(InMacroFile::new(self.expanded.file_id, tokens))
814    }
815
816    /// Maps the passed in file range down into a macro expansion if it is the input to a macro call.
817    /// Unlike [`map_range_down_exact`], this will consider spans that contain the given span.
818    ///
819    /// Note this does a linear search through the entire backing vector of the spanmap.
820    pub fn map_range_down(
821        &self,
822        span: Span,
823    ) -> Option<InMacroFile<impl Iterator<Item = (SyntaxToken, SyntaxContext)> + '_>> {
824        let tokens = self.exp_map.ranges_with_span(span).flat_map(move |(range, ctx)| {
825            self.expanded.value.covering_element(range).into_token().zip(Some(ctx))
826        });
827
828        Some(InMacroFile::new(self.expanded.file_id, tokens))
829    }
830
831    /// Looks up the span at the given offset.
832    pub fn span_for_offset(
833        &self,
834        db: &dyn ExpandDatabase,
835        offset: TextSize,
836    ) -> (FileRange, SyntaxContext) {
837        debug_assert!(self.expanded.value.text_range().contains(offset));
838        span_for_offset(db, &self.exp_map, offset)
839    }
840
841    /// Maps up the text range out of the expansion hierarchy back into the original file its from.
842    pub fn map_node_range_up(
843        &self,
844        db: &dyn ExpandDatabase,
845        range: TextRange,
846    ) -> Option<(FileRange, SyntaxContext)> {
847        debug_assert!(self.expanded.value.text_range().contains_range(range));
848        map_node_range_up(db, &self.exp_map, range)
849    }
850
851    /// Maps up the text range out of the expansion into is macro call.
852    pub fn map_range_up_once(
853        &self,
854        db: &dyn ExpandDatabase,
855        token: TextRange,
856    ) -> InFile<smallvec::SmallVec<[TextRange; 1]>> {
857        debug_assert!(self.expanded.value.text_range().contains_range(token));
858        let span = self.exp_map.span_at(token.start());
859        match &self.arg_map {
860            SpanMap::RealSpanMap(_) => {
861                let file_id = EditionedFileId::from_span(db, span.anchor.file_id).into();
862                let anchor_offset =
863                    db.ast_id_map(file_id).get_erased(span.anchor.ast_id).text_range().start();
864                InFile { file_id, value: smallvec::smallvec![span.range + anchor_offset] }
865            }
866            SpanMap::ExpansionSpanMap(arg_map) => {
867                let arg_range = self
868                    .arg
869                    .value
870                    .as_ref()
871                    .map_or_else(|| TextRange::empty(TextSize::from(0)), |it| it.text_range());
872                InFile::new(
873                    self.arg.file_id,
874                    arg_map
875                        .ranges_with_span_exact(span)
876                        .filter(|(range, _)| range.intersect(arg_range).is_some())
877                        .map(TupleExt::head)
878                        .collect(),
879                )
880            }
881        }
882    }
883
884    pub fn new(db: &dyn ExpandDatabase, macro_file: MacroCallId) -> ExpansionInfo {
885        let _p = tracing::info_span!("ExpansionInfo::new").entered();
886        let loc = db.lookup_intern_macro_call(macro_file);
887
888        let arg_tt = loc.kind.arg(db);
889        let arg_map = db.span_map(arg_tt.file_id);
890
891        let (parse, exp_map) = db.parse_macro_expansion(macro_file).value;
892        let expanded = InMacroFile { file_id: macro_file, value: parse.syntax_node() };
893
894        ExpansionInfo { expanded, loc, arg: arg_tt, exp_map, arg_map }
895    }
896}
897
898/// Maps up the text range out of the expansion hierarchy back into the original file its from only
899/// considering the root spans contained.
900/// Unlike [`map_node_range_up`], this will not return `None` if any anchors or syntax contexts differ.
901pub fn map_node_range_up_rooted(
902    db: &dyn ExpandDatabase,
903    exp_map: &ExpansionSpanMap,
904    range: TextRange,
905) -> Option<FileRange> {
906    let mut spans = exp_map.spans_for_range(range).filter(|span| span.ctx.is_root());
907    let Span { range, anchor, ctx: _ } = spans.next()?;
908    let mut start = range.start();
909    let mut end = range.end();
910
911    for span in spans {
912        if span.anchor != anchor {
913            return None;
914        }
915        start = start.min(span.range.start());
916        end = end.max(span.range.end());
917    }
918    let file_id = EditionedFileId::from_span(db, anchor.file_id);
919    let anchor_offset =
920        db.ast_id_map(file_id.into()).get_erased(anchor.ast_id).text_range().start();
921    Some(FileRange { file_id, range: TextRange::new(start, end) + anchor_offset })
922}
923
924/// Maps up the text range out of the expansion hierarchy back into the original file its from.
925///
926/// this will return `None` if any anchors or syntax contexts differ.
927pub fn map_node_range_up(
928    db: &dyn ExpandDatabase,
929    exp_map: &ExpansionSpanMap,
930    range: TextRange,
931) -> Option<(FileRange, SyntaxContext)> {
932    let mut spans = exp_map.spans_for_range(range);
933    let Span { range, anchor, ctx } = spans.next()?;
934    let mut start = range.start();
935    let mut end = range.end();
936
937    for span in spans {
938        if span.anchor != anchor || span.ctx != ctx {
939            return None;
940        }
941        start = start.min(span.range.start());
942        end = end.max(span.range.end());
943    }
944    let file_id = EditionedFileId::from_span(db, anchor.file_id);
945    let anchor_offset =
946        db.ast_id_map(file_id.into()).get_erased(anchor.ast_id).text_range().start();
947    Some((FileRange { file_id, range: TextRange::new(start, end) + anchor_offset }, ctx))
948}
949
950/// Maps up the text range out of the expansion hierarchy back into the original file its from.
951/// This version will aggregate the ranges of all spans with the same anchor and syntax context.
952pub fn map_node_range_up_aggregated(
953    db: &dyn ExpandDatabase,
954    exp_map: &ExpansionSpanMap,
955    range: TextRange,
956) -> FxHashMap<(SpanAnchor, SyntaxContext), TextRange> {
957    let mut map = FxHashMap::default();
958    for span in exp_map.spans_for_range(range) {
959        let range = map.entry((span.anchor, span.ctx)).or_insert_with(|| span.range);
960        *range = TextRange::new(
961            range.start().min(span.range.start()),
962            range.end().max(span.range.end()),
963        );
964    }
965    for ((anchor, _), range) in &mut map {
966        let file_id = EditionedFileId::from_span(db, anchor.file_id);
967        let anchor_offset =
968            db.ast_id_map(file_id.into()).get_erased(anchor.ast_id).text_range().start();
969        *range += anchor_offset;
970    }
971    map
972}
973
974/// Looks up the span at the given offset.
975pub fn span_for_offset(
976    db: &dyn ExpandDatabase,
977    exp_map: &ExpansionSpanMap,
978    offset: TextSize,
979) -> (FileRange, SyntaxContext) {
980    let span = exp_map.span_at(offset);
981    let file_id = EditionedFileId::from_span(db, span.anchor.file_id);
982    let anchor_offset =
983        db.ast_id_map(file_id.into()).get_erased(span.anchor.ast_id).text_range().start();
984    (FileRange { file_id, range: span.range + anchor_offset }, span.ctx)
985}
986
987/// In Rust, macros expand token trees to token trees. When we want to turn a
988/// token tree into an AST node, we need to figure out what kind of AST node we
989/// want: something like `foo` can be a type, an expression, or a pattern.
990///
991/// Naively, one would think that "what this expands to" is a property of a
992/// particular macro: macro `m1` returns an item, while macro `m2` returns an
993/// expression, etc. That's not the case -- macros are polymorphic in the
994/// result, and can expand to any type of the AST node.
995///
996/// What defines the actual AST node is the syntactic context of the macro
997/// invocation. As a contrived example, in `let T![*] = T![*];` the first `T`
998/// expands to a pattern, while the second one expands to an expression.
999///
1000/// `ExpandTo` captures this bit of information about a particular macro call
1001/// site.
1002#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
1003pub enum ExpandTo {
1004    Statements,
1005    Items,
1006    Pattern,
1007    Type,
1008    Expr,
1009}
1010
1011impl ExpandTo {
1012    pub fn from_call_site(call: &ast::MacroCall) -> ExpandTo {
1013        use syntax::SyntaxKind::*;
1014
1015        let syn = call.syntax();
1016
1017        let parent = match syn.parent() {
1018            Some(it) => it,
1019            None => return ExpandTo::Statements,
1020        };
1021
1022        // FIXME: macros in statement position are treated as expression statements, they should
1023        // probably be their own statement kind. The *grand*parent indicates what's valid.
1024        if parent.kind() == MACRO_EXPR
1025            && parent
1026                .parent()
1027                .is_some_and(|p| matches!(p.kind(), EXPR_STMT | STMT_LIST | MACRO_STMTS))
1028        {
1029            return ExpandTo::Statements;
1030        }
1031
1032        match parent.kind() {
1033            MACRO_ITEMS | SOURCE_FILE | ITEM_LIST => ExpandTo::Items,
1034            MACRO_STMTS | EXPR_STMT | STMT_LIST => ExpandTo::Statements,
1035            MACRO_PAT => ExpandTo::Pattern,
1036            MACRO_TYPE => ExpandTo::Type,
1037
1038            ARG_LIST | ARRAY_EXPR | AWAIT_EXPR | BIN_EXPR | BREAK_EXPR | CALL_EXPR | CAST_EXPR
1039            | CLOSURE_EXPR | FIELD_EXPR | FOR_EXPR | IF_EXPR | INDEX_EXPR | LET_EXPR
1040            | MATCH_ARM | MATCH_EXPR | MATCH_GUARD | METHOD_CALL_EXPR | PAREN_EXPR | PATH_EXPR
1041            | PREFIX_EXPR | RANGE_EXPR | RECORD_EXPR_FIELD | REF_EXPR | RETURN_EXPR | TRY_EXPR
1042            | TUPLE_EXPR | WHILE_EXPR | MACRO_EXPR => ExpandTo::Expr,
1043            _ => {
1044                // Unknown , Just guess it is `Items`
1045                ExpandTo::Items
1046            }
1047        }
1048    }
1049}
1050
1051intern::impl_internable!(ModPath, attrs::AttrInput);
1052
1053#[salsa_macros::interned(no_lifetime, debug)]
1054#[doc(alias = "MacroFileId")]
1055pub struct MacroCallId {
1056    pub loc: MacroCallLoc,
1057}
1058
1059impl From<span::MacroCallId> for MacroCallId {
1060    #[inline]
1061    fn from(value: span::MacroCallId) -> Self {
1062        MacroCallId::from_id(value.0)
1063    }
1064}
1065
1066impl From<MacroCallId> for span::MacroCallId {
1067    #[inline]
1068    fn from(value: MacroCallId) -> span::MacroCallId {
1069        span::MacroCallId(value.as_id())
1070    }
1071}
1072
1073#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, salsa_macros::Supertype)]
1074pub enum HirFileId {
1075    FileId(EditionedFileId),
1076    MacroFile(MacroCallId),
1077}
1078
1079impl From<EditionedFileId> for HirFileId {
1080    #[inline]
1081    fn from(file_id: EditionedFileId) -> Self {
1082        HirFileId::FileId(file_id)
1083    }
1084}
1085
1086impl From<MacroCallId> for HirFileId {
1087    #[inline]
1088    fn from(file_id: MacroCallId) -> Self {
1089        HirFileId::MacroFile(file_id)
1090    }
1091}
1092
1093impl HirFileId {
1094    #[inline]
1095    pub fn macro_file(self) -> Option<MacroCallId> {
1096        match self {
1097            HirFileId::FileId(_) => None,
1098            HirFileId::MacroFile(it) => Some(it),
1099        }
1100    }
1101
1102    #[inline]
1103    pub fn is_macro(self) -> bool {
1104        matches!(self, HirFileId::MacroFile(_))
1105    }
1106
1107    #[inline]
1108    pub fn file_id(self) -> Option<EditionedFileId> {
1109        match self {
1110            HirFileId::FileId(it) => Some(it),
1111            HirFileId::MacroFile(_) => None,
1112        }
1113    }
1114}
1115
1116impl PartialEq<EditionedFileId> for HirFileId {
1117    fn eq(&self, &other: &EditionedFileId) -> bool {
1118        *self == HirFileId::from(other)
1119    }
1120}
1121impl PartialEq<HirFileId> for EditionedFileId {
1122    fn eq(&self, &other: &HirFileId) -> bool {
1123        other == HirFileId::from(*self)
1124    }
1125}
ra_ap_hir_expand/lib.rs

ra_ap_hir_expand/
lib.rs
