Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-expand/src/db.rs')
| -rw-r--r-- | crates/hir-expand/src/db.rs | 479 |
1 files changed, 311 insertions, 168 deletions
diff --git a/crates/hir-expand/src/db.rs b/crates/hir-expand/src/db.rs index 78b2db7306..309c0930d1 100644 --- a/crates/hir-expand/src/db.rs +++ b/crates/hir-expand/src/db.rs @@ -1,9 +1,9 @@ //! Defines database & queries for macro expansion. -use base_db::{salsa, Edition, SourceDatabase}; +use base_db::{salsa, CrateId, Edition, SourceDatabase}; use either::Either; use limit::Limit; -use mbe::syntax_node_to_token_tree; +use mbe::{syntax_node_to_token_tree, ValueResult}; use rustc_hash::FxHashSet; use syntax::{ ast::{self, HasAttrs, HasDocComments}, @@ -13,7 +13,7 @@ use triomphe::Arc; use crate::{ ast_id_map::AstIdMap, builtin_attr_macro::pseudo_derive_attr_expansion, - builtin_fn_macro::EagerExpander, fixup, hygiene::HygieneFrame, tt, BuiltinAttrExpander, + builtin_fn_macro::EagerExpander, fixup, hygiene::HygieneFrame, tt, AstId, BuiltinAttrExpander, BuiltinDeriveExpander, BuiltinFnLikeExpander, EagerCallInfo, ExpandError, ExpandResult, ExpandTo, HirFileId, HirFileIdRepr, MacroCallId, MacroCallKind, MacroCallLoc, MacroDefId, MacroDefKind, MacroFile, ProcMacroExpander, @@ -28,61 +28,67 @@ use crate::{ static TOKEN_LIMIT: Limit = Limit::new(1_048_576); #[derive(Debug, Clone, Eq, PartialEq)] +/// Old-style `macro_rules` or the new macros 2.0 +pub struct DeclarativeMacroExpander { + pub mac: mbe::DeclarativeMacro, + pub def_site_token_map: mbe::TokenMap, +} + +impl DeclarativeMacroExpander { + pub fn expand(&self, tt: tt::Subtree) -> ExpandResult<tt::Subtree> { + match self.mac.err() { + Some(e) => ExpandResult::new( + tt::Subtree::empty(), + ExpandError::other(format!("invalid macro definition: {e}")), + ), + None => self.mac.expand(tt).map_err(Into::into), + } + } + + pub fn map_id_down(&self, token_id: tt::TokenId) -> tt::TokenId { + self.mac.map_id_down(token_id) + } + + pub fn map_id_up(&self, token_id: tt::TokenId) -> (tt::TokenId, mbe::Origin) { + self.mac.map_id_up(token_id) + } +} + +#[derive(Debug, Clone, Eq, PartialEq)] pub enum TokenExpander { - /// Old-style `macro_rules` or the new macros 2.0 - DeclarativeMacro { mac: mbe::DeclarativeMacro, def_site_token_map: mbe::TokenMap }, + DeclarativeMacro(Arc<DeclarativeMacroExpander>), /// Stuff like `line!` and `file!`. - Builtin(BuiltinFnLikeExpander), + BuiltIn(BuiltinFnLikeExpander), /// Built-in eagerly expanded fn-like macros (`include!`, `concat!`, etc.) - BuiltinEager(EagerExpander), + BuiltInEager(EagerExpander), /// `global_allocator` and such. - BuiltinAttr(BuiltinAttrExpander), + BuiltInAttr(BuiltinAttrExpander), /// `derive(Copy)` and such. - BuiltinDerive(BuiltinDeriveExpander), + BuiltInDerive(BuiltinDeriveExpander), /// The thing we love the most here in rust-analyzer -- procedural macros. ProcMacro(ProcMacroExpander), } +// FIXME: Get rid of these methods impl TokenExpander { - fn expand( - &self, - db: &dyn ExpandDatabase, - id: MacroCallId, - tt: &tt::Subtree, - ) -> ExpandResult<tt::Subtree> { - match self { - TokenExpander::DeclarativeMacro { mac, .. } => mac.expand(tt).map_err(Into::into), - TokenExpander::Builtin(it) => it.expand(db, id, tt).map_err(Into::into), - TokenExpander::BuiltinEager(it) => it.expand(db, id, tt).map_err(Into::into), - TokenExpander::BuiltinAttr(it) => it.expand(db, id, tt), - TokenExpander::BuiltinDerive(it) => it.expand(db, id, tt), - TokenExpander::ProcMacro(_) => { - // We store the result in salsa db to prevent non-deterministic behavior in - // some proc-macro implementation - // See #4315 for details - db.expand_proc_macro(id) - } - } - } - pub(crate) fn map_id_down(&self, id: tt::TokenId) -> tt::TokenId { match self { - TokenExpander::DeclarativeMacro { mac, .. } => mac.map_id_down(id), - TokenExpander::Builtin(..) - | TokenExpander::BuiltinEager(..) - | TokenExpander::BuiltinAttr(..) - | TokenExpander::BuiltinDerive(..) + TokenExpander::DeclarativeMacro(expander) => expander.map_id_down(id), + TokenExpander::BuiltIn(..) + | TokenExpander::BuiltInEager(..) + | TokenExpander::BuiltInAttr(..) + | TokenExpander::BuiltInDerive(..) | TokenExpander::ProcMacro(..) => id, } } pub(crate) fn map_id_up(&self, id: tt::TokenId) -> (tt::TokenId, mbe::Origin) { match self { - TokenExpander::DeclarativeMacro { mac, .. } => mac.map_id_up(id), - TokenExpander::Builtin(..) - | TokenExpander::BuiltinEager(..) - | TokenExpander::BuiltinAttr(..) - | TokenExpander::BuiltinDerive(..) + TokenExpander::DeclarativeMacro(expander) => expander.map_id_up(id), + TokenExpander::BuiltIn(..) + | TokenExpander::BuiltInEager(..) + | TokenExpander::BuiltInAttr(..) + | TokenExpander::BuiltInDerive(..) | TokenExpander::ProcMacro(..) => (id, mbe::Origin::Call), } } @@ -118,14 +124,26 @@ pub trait ExpandDatabase: SourceDatabase { fn macro_arg( &self, id: MacroCallId, - ) -> Option<Arc<(tt::Subtree, mbe::TokenMap, fixup::SyntaxFixupUndoInfo)>>; + ) -> ValueResult< + Option<Arc<(tt::Subtree, mbe::TokenMap, fixup::SyntaxFixupUndoInfo)>>, + Arc<Box<[SyntaxError]>>, + >; /// Extracts syntax node, corresponding to a macro call. That's a firewall /// query, only typing in the macro call itself changes the returned /// subtree. - fn macro_arg_text(&self, id: MacroCallId) -> Option<GreenNode>; - /// Gets the expander for this macro. This compiles declarative macros, and - /// just fetches procedural ones. - fn macro_def(&self, id: MacroDefId) -> Result<Arc<TokenExpander>, mbe::ParseError>; + fn macro_arg_node( + &self, + id: MacroCallId, + ) -> ValueResult<Option<GreenNode>, Arc<Box<[SyntaxError]>>>; + /// Fetches the expander for this macro. + #[salsa::transparent] + fn macro_expander(&self, id: MacroDefId) -> TokenExpander; + /// Fetches (and compiles) the expander of this decl macro. + fn decl_macro_expander( + &self, + def_crate: CrateId, + id: AstId<ast::Macro>, + ) -> Arc<DeclarativeMacroExpander>; /// Expand macro call to a token tree. // This query is LRU cached @@ -141,8 +159,8 @@ pub trait ExpandDatabase: SourceDatabase { /// Special case of the previous query for procedural macros. We can't LRU /// proc macros, since they are not deterministic in general, and /// non-determinism breaks salsa in a very, very, very bad way. - /// @edwin0cheng heroically debugged this once! - fn expand_proc_macro(&self, call: MacroCallId) -> ExpandResult<tt::Subtree>; + /// @edwin0cheng heroically debugged this once! See #4315 for details + fn expand_proc_macro(&self, call: MacroCallId) -> ExpandResult<Arc<tt::Subtree>>; /// Firewall query that returns the errors from the `parse_macro_expansion` query. fn parse_macro_expansion_error( &self, @@ -163,7 +181,6 @@ pub fn expand_speculative( token_to_map: SyntaxToken, ) -> Option<(SyntaxNode, SyntaxToken)> { let loc = db.lookup_intern_macro_call(actual_macro_call); - let macro_def = db.macro_def(loc.def).ok()?; let token_range = token_to_map.text_range(); // Build the subtree and token mapping for the speculative args @@ -221,7 +238,12 @@ pub fn expand_speculative( None => { let range = token_range.checked_sub(speculative_args.text_range().start())?; let token_id = spec_args_tmap.token_by_range(range)?; - macro_def.map_id_down(token_id) + match loc.def.kind { + MacroDefKind::Declarative(it) => { + db.decl_macro_expander(loc.krate, it).map_id_down(token_id) + } + _ => token_id, + } } }; @@ -235,7 +257,17 @@ pub fn expand_speculative( MacroDefKind::BuiltInAttr(BuiltinAttrExpander::Derive, _) => { pseudo_derive_attr_expansion(&tt, attr_arg.as_ref()?) } - _ => macro_def.expand(db, actual_macro_call, &tt), + MacroDefKind::BuiltInDerive(expander, ..) => { + // this cast is a bit sus, can we avoid losing the typedness here? + let adt = ast::Adt::cast(speculative_args.clone()).unwrap(); + expander.expand(db, actual_macro_call, &adt, &spec_args_tmap) + } + MacroDefKind::Declarative(it) => db.decl_macro_expander(loc.krate, it).expand(tt), + MacroDefKind::BuiltIn(it, _) => it.expand(db, actual_macro_call, &tt).map_err(Into::into), + MacroDefKind::BuiltInEager(it, _) => { + it.expand(db, actual_macro_call, &tt).map_err(Into::into) + } + MacroDefKind::BuiltInAttr(it, _) => it.expand(db, actual_macro_call, &tt), }; let expand_to = macro_expand_to(db, actual_macro_call); @@ -297,17 +329,31 @@ fn parse_macro_expansion( ExpandResult { value: (parse, Arc::new(rev_token_map)), err } } +fn parse_macro_expansion_error( + db: &dyn ExpandDatabase, + macro_call_id: MacroCallId, +) -> ExpandResult<Box<[SyntaxError]>> { + db.parse_macro_expansion(MacroFile { macro_call_id }) + .map(|it| it.0.errors().to_vec().into_boxed_slice()) +} + fn macro_arg( db: &dyn ExpandDatabase, id: MacroCallId, -) -> Option<Arc<(tt::Subtree, mbe::TokenMap, fixup::SyntaxFixupUndoInfo)>> { +) -> ValueResult< + Option<Arc<(tt::Subtree, mbe::TokenMap, fixup::SyntaxFixupUndoInfo)>>, + Arc<Box<[SyntaxError]>>, +> { let loc = db.lookup_intern_macro_call(id); - if let Some(EagerCallInfo { arg, arg_id: Some(_), error: _ }) = loc.eager.as_deref() { - return Some(Arc::new((arg.0.clone(), arg.1.clone(), Default::default()))); + if let Some(EagerCallInfo { arg, arg_id: _, error: _ }) = loc.eager.as_deref() { + return ValueResult::ok(Some(Arc::new((arg.0.clone(), arg.1.clone(), Default::default())))); } - let arg = db.macro_arg_text(id)?; + let ValueResult { value, err } = db.macro_arg_node(id); + let Some(arg) = value else { + return ValueResult { value: None, err }; + }; let node = SyntaxNode::new_root(arg); let censor = censor_for_macro_input(&loc, &node); @@ -325,9 +371,16 @@ fn macro_arg( // proc macros expect their inputs without parentheses, MBEs expect it with them included tt.delimiter = tt::Delimiter::unspecified(); } - Some(Arc::new((tt, tmap, fixups.undo_info))) + let val = Some(Arc::new((tt, tmap, fixups.undo_info))); + match err { + Some(err) => ValueResult::new(val, err), + None => ValueResult::ok(val), + } } +/// Certain macro calls expect some nodes in the input to be preprocessed away, namely: +/// - derives expect all `#[derive(..)]` invocations up to the currently invoked one to be stripped +/// - attributes expect the invoking attribute to be stripped fn censor_for_macro_input(loc: &MacroCallLoc, node: &SyntaxNode) -> FxHashSet<SyntaxNode> { // FIXME: handle `cfg_attr` (|| { @@ -364,9 +417,44 @@ fn censor_for_macro_input(loc: &MacroCallLoc, node: &SyntaxNode) -> FxHashSet<Sy .unwrap_or_default() } -fn macro_arg_text(db: &dyn ExpandDatabase, id: MacroCallId) -> Option<GreenNode> { +fn macro_arg_node( + db: &dyn ExpandDatabase, + id: MacroCallId, +) -> ValueResult<Option<GreenNode>, Arc<Box<[SyntaxError]>>> { + let err = || -> Arc<Box<[_]>> { + Arc::new(Box::new([SyntaxError::new_at_offset( + "invalid macro call".to_owned(), + syntax::TextSize::from(0), + )])) + }; let loc = db.lookup_intern_macro_call(id); - let arg = loc.kind.arg(db)?; + let arg = if let MacroDefKind::BuiltInEager(..) = loc.def.kind { + let res = if let Some(EagerCallInfo { arg, .. }) = loc.eager.as_deref() { + Some(mbe::token_tree_to_syntax_node(&arg.0, mbe::TopEntryPoint::Expr).0) + } else { + loc.kind + .arg(db) + .and_then(|arg| ast::TokenTree::cast(arg.value)) + .map(|tt| tt.reparse_as_expr().to_syntax()) + }; + + match res { + Some(res) if res.errors().is_empty() => res.syntax_node(), + Some(res) => { + return ValueResult::new( + Some(res.syntax_node().green().into()), + // Box::<[_]>::from(res.errors()), not stable yet + Arc::new(res.errors().to_vec().into_boxed_slice()), + ); + } + None => return ValueResult::only_err(err()), + } + } else { + match loc.kind.arg(db) { + Some(res) => res.value, + None => return ValueResult::only_err(err()), + } + }; if matches!(loc.kind, MacroCallKind::FnLike { .. }) { let first = arg.first_child_or_token().map_or(T![.], |it| it.kind()); let last = arg.last_child_or_token().map_or(T![.], |it| it.kind()); @@ -381,101 +469,146 @@ fn macro_arg_text(db: &dyn ExpandDatabase, id: MacroCallId) -> Option<GreenNode> // Some day, we'll have explicit recursion counters for all // recursive things, at which point this code might be removed. cov_mark::hit!(issue9358_bad_macro_stack_overflow); - return None; + return ValueResult::only_err(Arc::new(Box::new([SyntaxError::new( + "unbalanced token tree".to_owned(), + arg.text_range(), + )]))); } } - if let Some(EagerCallInfo { arg, .. }) = loc.eager.as_deref() { - Some( - mbe::token_tree_to_syntax_node(&arg.0, mbe::TopEntryPoint::Expr) - .0 - .syntax_node() - .green() - .into(), - ) - } else { - Some(arg.green().into()) - } + ValueResult::ok(Some(arg.green().into())) } -fn macro_def( +fn decl_macro_expander( db: &dyn ExpandDatabase, - id: MacroDefId, -) -> Result<Arc<TokenExpander>, mbe::ParseError> { + def_crate: CrateId, + id: AstId<ast::Macro>, +) -> Arc<DeclarativeMacroExpander> { + let is_2021 = db.crate_graph()[def_crate].edition >= Edition::Edition2021; + let (mac, def_site_token_map) = match id.to_node(db) { + ast::Macro::MacroRules(macro_rules) => match macro_rules.token_tree() { + Some(arg) => { + let (tt, def_site_token_map) = mbe::syntax_node_to_token_tree(arg.syntax()); + let mac = mbe::DeclarativeMacro::parse_macro_rules(&tt, is_2021); + (mac, def_site_token_map) + } + None => ( + mbe::DeclarativeMacro::from_err( + mbe::ParseError::Expected("expected a token tree".into()), + is_2021, + ), + Default::default(), + ), + }, + ast::Macro::MacroDef(macro_def) => match macro_def.body() { + Some(arg) => { + let (tt, def_site_token_map) = mbe::syntax_node_to_token_tree(arg.syntax()); + let mac = mbe::DeclarativeMacro::parse_macro2(&tt, is_2021); + (mac, def_site_token_map) + } + None => ( + mbe::DeclarativeMacro::from_err( + mbe::ParseError::Expected("expected a token tree".into()), + is_2021, + ), + Default::default(), + ), + }, + }; + Arc::new(DeclarativeMacroExpander { mac, def_site_token_map }) +} + +fn macro_expander(db: &dyn ExpandDatabase, id: MacroDefId) -> TokenExpander { match id.kind { MacroDefKind::Declarative(ast_id) => { - let is_2021 = db.crate_graph()[id.krate].edition >= Edition::Edition2021; - let (mac, def_site_token_map) = match ast_id.to_node(db) { - ast::Macro::MacroRules(macro_rules) => { - let arg = macro_rules - .token_tree() - .ok_or_else(|| mbe::ParseError::Expected("expected a token tree".into()))?; - let (tt, def_site_token_map) = mbe::syntax_node_to_token_tree(arg.syntax()); - let mac = mbe::DeclarativeMacro::parse_macro_rules(&tt, is_2021)?; - (mac, def_site_token_map) - } - ast::Macro::MacroDef(macro_def) => { - let arg = macro_def - .body() - .ok_or_else(|| mbe::ParseError::Expected("expected a token tree".into()))?; - let (tt, def_site_token_map) = mbe::syntax_node_to_token_tree(arg.syntax()); - let mac = mbe::DeclarativeMacro::parse_macro2(&tt, is_2021)?; - (mac, def_site_token_map) - } - }; - Ok(Arc::new(TokenExpander::DeclarativeMacro { mac, def_site_token_map })) - } - MacroDefKind::BuiltIn(expander, _) => Ok(Arc::new(TokenExpander::Builtin(expander))), - MacroDefKind::BuiltInAttr(expander, _) => { - Ok(Arc::new(TokenExpander::BuiltinAttr(expander))) + TokenExpander::DeclarativeMacro(db.decl_macro_expander(id.krate, ast_id)) } - MacroDefKind::BuiltInDerive(expander, _) => { - Ok(Arc::new(TokenExpander::BuiltinDerive(expander))) - } - MacroDefKind::BuiltInEager(expander, ..) => { - Ok(Arc::new(TokenExpander::BuiltinEager(expander))) - } - MacroDefKind::ProcMacro(expander, ..) => Ok(Arc::new(TokenExpander::ProcMacro(expander))), + MacroDefKind::BuiltIn(expander, _) => TokenExpander::BuiltIn(expander), + MacroDefKind::BuiltInAttr(expander, _) => TokenExpander::BuiltInAttr(expander), + MacroDefKind::BuiltInDerive(expander, _) => TokenExpander::BuiltInDerive(expander), + MacroDefKind::BuiltInEager(expander, ..) => TokenExpander::BuiltInEager(expander), + MacroDefKind::ProcMacro(expander, ..) => TokenExpander::ProcMacro(expander), } } fn macro_expand(db: &dyn ExpandDatabase, id: MacroCallId) -> ExpandResult<Arc<tt::Subtree>> { let _p = profile::span("macro_expand"); let loc = db.lookup_intern_macro_call(id); - if let Some(EagerCallInfo { arg, arg_id: None, error }) = loc.eager.as_deref() { - // This is an input expansion for an eager macro. These are already pre-expanded - return ExpandResult { value: Arc::new(arg.0.clone()), err: error.clone() }; - } - let expander = match db.macro_def(loc.def) { - Ok(it) => it, - // FIXME: We should make sure to enforce a variant that invalid macro - // definitions do not get expanders that could reach this call path! - Err(err) => { - return ExpandResult { - value: Arc::new(tt::Subtree { - delimiter: tt::Delimiter::UNSPECIFIED, - token_trees: vec![], - }), - err: Some(ExpandError::other(format!("invalid macro definition: {err}"))), - } + + let ExpandResult { value: tt, mut err } = match loc.def.kind { + MacroDefKind::ProcMacro(..) => return db.expand_proc_macro(id), + MacroDefKind::BuiltInDerive(expander, ..) => { + let arg = db.macro_arg_node(id).value.unwrap(); + + let node = SyntaxNode::new_root(arg); + let censor = censor_for_macro_input(&loc, &node); + let mut fixups = fixup::fixup_syntax(&node); + fixups.replace.extend(censor.into_iter().map(|node| (node.into(), Vec::new()))); + let (tmap, _) = mbe::syntax_node_to_token_map_with_modifications( + &node, + fixups.token_map, + fixups.next_id, + fixups.replace, + fixups.append, + ); + + // this cast is a bit sus, can we avoid losing the typedness here? + let adt = ast::Adt::cast(node).unwrap(); + let mut res = expander.expand(db, id, &adt, &tmap); + fixup::reverse_fixups(&mut res.value, &tmap, &fixups.undo_info); + res + } + _ => { + let ValueResult { value, err } = db.macro_arg(id); + let Some(macro_arg) = value else { + return ExpandResult { + value: Arc::new(tt::Subtree { + delimiter: tt::Delimiter::UNSPECIFIED, + token_trees: Vec::new(), + }), + // FIXME: We should make sure to enforce an invariant that invalid macro + // calls do not reach this call path! + err: Some(ExpandError::other("invalid token tree")), + }; + }; + + let (arg, arg_tm, undo_info) = &*macro_arg; + let mut res = match loc.def.kind { + MacroDefKind::Declarative(id) => { + db.decl_macro_expander(loc.def.krate, id).expand(arg.clone()) + } + MacroDefKind::BuiltIn(it, _) => it.expand(db, id, &arg).map_err(Into::into), + // This might look a bit odd, but we do not expand the inputs to eager macros here. + // Eager macros inputs are expanded, well, eagerly when we collect the macro calls. + // That kind of expansion uses the ast id map of an eager macros input though which goes through + // the HirFileId machinery. As eager macro inputs are assigned a macro file id that query + // will end up going through here again, whereas we want to just want to inspect the raw input. + // As such we just return the input subtree here. + MacroDefKind::BuiltInEager(..) if loc.eager.is_none() => { + let mut arg = arg.clone(); + fixup::reverse_fixups(&mut arg, arg_tm, undo_info); + + return ExpandResult { + value: Arc::new(arg), + err: err.map(|err| { + let mut buf = String::new(); + for err in &**err { + use std::fmt::Write; + _ = write!(buf, "{}, ", err); + } + buf.pop(); + buf.pop(); + ExpandError::other(buf) + }), + }; + } + MacroDefKind::BuiltInEager(it, _) => it.expand(db, id, &arg).map_err(Into::into), + MacroDefKind::BuiltInAttr(it, _) => it.expand(db, id, &arg), + _ => unreachable!(), + }; + fixup::reverse_fixups(&mut res.value, arg_tm, undo_info); + res } }; - let Some(macro_arg) = db.macro_arg(id) else { - return ExpandResult { - value: Arc::new( - tt::Subtree { - delimiter: tt::Delimiter::UNSPECIFIED, - token_trees: Vec::new(), - }, - ), - // FIXME: We should make sure to enforce a variant that invalid macro - // calls do not reach this call path! - err: Some(ExpandError::other( - "invalid token tree" - )), - }; - }; - let (arg_tt, arg_tm, undo_info) = &*macro_arg; - let ExpandResult { value: mut tt, mut err } = expander.expand(db, id, arg_tt); if let Some(EagerCallInfo { error, .. }) = loc.eager.as_deref() { // FIXME: We should report both errors! @@ -483,48 +616,29 @@ fn macro_expand(db: &dyn ExpandDatabase, id: MacroCallId) -> ExpandResult<Arc<tt } // Set a hard limit for the expanded tt - let count = tt.count(); - if TOKEN_LIMIT.check(count).is_err() { - return ExpandResult { - value: Arc::new(tt::Subtree { - delimiter: tt::Delimiter::UNSPECIFIED, - token_trees: vec![], - }), - err: Some(ExpandError::other(format!( - "macro invocation exceeds token limit: produced {} tokens, limit is {}", - count, - TOKEN_LIMIT.inner(), - ))), - }; + if let Err(value) = check_tt_count(&tt) { + return value; } - fixup::reverse_fixups(&mut tt, arg_tm, undo_info); - ExpandResult { value: Arc::new(tt), err } } -fn parse_macro_expansion_error( - db: &dyn ExpandDatabase, - macro_call_id: MacroCallId, -) -> ExpandResult<Box<[SyntaxError]>> { - db.parse_macro_expansion(MacroFile { macro_call_id }) - .map(|it| it.0.errors().to_vec().into_boxed_slice()) -} - -fn expand_proc_macro(db: &dyn ExpandDatabase, id: MacroCallId) -> ExpandResult<tt::Subtree> { +fn expand_proc_macro(db: &dyn ExpandDatabase, id: MacroCallId) -> ExpandResult<Arc<tt::Subtree>> { let loc = db.lookup_intern_macro_call(id); - let Some(macro_arg) = db.macro_arg(id) else { + let Some(macro_arg) = db.macro_arg(id).value else { return ExpandResult { - value: tt::Subtree { + value: Arc::new(tt::Subtree { delimiter: tt::Delimiter::UNSPECIFIED, token_trees: Vec::new(), - }, - err: Some(ExpandError::other( - "invalid token tree" - )), + }), + // FIXME: We should make sure to enforce an invariant that invalid macro + // calls do not reach this call path! + err: Some(ExpandError::other("invalid token tree")), }; }; + let (arg_tt, arg_tm, undo_info) = &*macro_arg; + let expander = match loc.def.kind { MacroDefKind::ProcMacro(expander, ..) => expander, _ => unreachable!(), @@ -533,13 +647,23 @@ fn expand_proc_macro(db: &dyn ExpandDatabase, id: MacroCallId) -> ExpandResult<t let attr_arg = match &loc.kind { MacroCallKind::Attr { attr_args, .. } => { let mut attr_args = attr_args.0.clone(); - mbe::Shift::new(¯o_arg.0).shift_all(&mut attr_args); + mbe::Shift::new(arg_tt).shift_all(&mut attr_args); Some(attr_args) } _ => None, }; - expander.expand(db, loc.def.krate, loc.krate, ¯o_arg.0, attr_arg.as_ref()) + let ExpandResult { value: mut tt, err } = + expander.expand(db, loc.def.krate, loc.krate, arg_tt, attr_arg.as_ref()); + + // Set a hard limit for the expanded tt + if let Err(value) = check_tt_count(&tt) { + return value; + } + + fixup::reverse_fixups(&mut tt, arg_tm, undo_info); + + ExpandResult { value: Arc::new(tt), err } } fn hygiene_frame(db: &dyn ExpandDatabase, file_id: HirFileId) -> Arc<HygieneFrame> { @@ -563,3 +687,22 @@ fn token_tree_to_syntax_node( }; mbe::token_tree_to_syntax_node(tt, entry_point) } + +fn check_tt_count(tt: &tt::Subtree) -> Result<(), ExpandResult<Arc<tt::Subtree>>> { + let count = tt.count(); + if TOKEN_LIMIT.check(count).is_err() { + Err(ExpandResult { + value: Arc::new(tt::Subtree { + delimiter: tt::Delimiter::UNSPECIFIED, + token_trees: vec![], + }), + err: Some(ExpandError::other(format!( + "macro invocation exceeds token limit: produced {} tokens, limit is {}", + count, + TOKEN_LIMIT.inner(), + ))), + }) + } else { + Ok(()) + } +} |