crates/hir_def/src/body/lower.rs

   1 //! Transforms `ast::Expr` into an equivalent `hir_def::expr::Expr`
   2 //! representation.
   3
   4 use std::{any::type_name, mem, sync::Arc};
   5
   6 use either::Either;
   7 use hir_expand::{
   8     hygiene::Hygiene,
   9     name::{name, AsName, Name},
  10     ExpandError, HirFileId, MacroDefId, MacroDefKind,
  11 };
  12 use la_arena::Arena;
  13 use profile::Count;
  14 use rustc_hash::FxHashMap;
  15 use syntax::{
  16     ast::{
  17         self, ArgListOwner, ArrayExprKind, AstChildren, LiteralKind, LoopBodyOwner, NameOwner,
  18         SlicePatComponents,
  19     },
  20     AstNode, AstPtr, SyntaxNodePtr,
  21 };
  22
  23 use crate::{
  24     adt::StructKind,
  25     body::{Body, BodySourceMap, Expander, LabelSource, PatPtr, SyntheticSyntax},
  26     builtin_type::{BuiltinFloat, BuiltinInt, BuiltinUint},
  27     db::DefDatabase,
  28     diagnostics::{InactiveCode, MacroError, UnresolvedProcMacro},
  29     expr::{
  30         dummy_expr_id, ArithOp, Array, BinaryOp, BindingAnnotation, CmpOp, Expr, ExprId, Label,
  31         LabelId, Literal, LogicOp, MatchArm, Ordering, Pat, PatId, RecordFieldPat, RecordLitField,
  32         Statement,
  33     },
  34     item_scope::BuiltinShadowMode,
  35     item_tree::{ItemTree, ItemTreeId, ItemTreeNode},
  36     path::{GenericArgs, Path},
  37     type_ref::{Mutability, Rawness, TypeRef},
  38     AdtId, BlockLoc, ConstLoc, ContainerId, DefWithBodyId, EnumLoc, FunctionLoc, Intern,
  39     ModuleDefId, StaticLoc, StructLoc, TraitLoc, TypeAliasLoc, UnionLoc,
  40 };
  41
  42 use super::{diagnostics::BodyDiagnostic, ExprSource, PatSource};
  43
  44 pub(crate) struct LowerCtx {
  45     hygiene: Hygiene,
  46 }
  47
  48 impl LowerCtx {
  49     pub(crate) fn new(db: &dyn DefDatabase, file_id: HirFileId) -> Self {
  50         LowerCtx { hygiene: Hygiene::new(db.upcast(), file_id) }
  51     }
  52     pub(crate) fn with_hygiene(hygiene: &Hygiene) -> Self {
  53         LowerCtx { hygiene: hygiene.clone() }
  54     }
  55
  56     pub(crate) fn lower_path(&self, ast: ast::Path) -> Option<Path> {
  57         Path::from_src(ast, &self.hygiene)
  58     }
  59 }
  60
  61 pub(super) fn lower(
  62     db: &dyn DefDatabase,
  63     def: DefWithBodyId,
  64     expander: Expander,
  65     params: Option<ast::ParamList>,
  66     body: Option<ast::Expr>,
  67 ) -> (Body, BodySourceMap) {
  68     let item_tree = db.item_tree(expander.current_file_id);
  69     ExprCollector {
  70         db,
  71         def,
  72         source_map: BodySourceMap::default(),
  73         body: Body {
  74             exprs: Arena::default(),
  75             pats: Arena::default(),
  76             labels: Arena::default(),
  77             params: Vec::new(),
  78             body_expr: dummy_expr_id(),
  79             item_scope: Default::default(),
  80             _c: Count::new(),
  81         },
  82         item_trees: {
  83             let mut map = FxHashMap::default();
  84             map.insert(expander.current_file_id, item_tree);
  85             map
  86         },
  87         expander,
  88     }
  89     .collect(params, body)
  90 }
  91
  92 struct ExprCollector<'a> {
  93     db: &'a dyn DefDatabase,
  94     def: DefWithBodyId,
  95     expander: Expander,
  96     body: Body,
  97     source_map: BodySourceMap,
  98
  99     item_trees: FxHashMap<HirFileId, Arc<ItemTree>>,
 100 }
 101
 102 impl ExprCollector<'_> {
 103     fn collect(
 104         mut self,
 105         param_list: Option<ast::ParamList>,
 106         body: Option<ast::Expr>,
 107     ) -> (Body, BodySourceMap) {
 108         if let Some(param_list) = param_list {
 109             if let Some(self_param) = param_list.self_param() {
 110                 let ptr = AstPtr::new(&self_param);
 111                 let param_pat = self.alloc_pat(
 112                     Pat::Bind {
 113                         name: name![self],
 114                         mode: BindingAnnotation::new(
 115                             self_param.mut_token().is_some() && self_param.amp_token().is_none(),
 116                             false,
 117                         ),
 118                         subpat: None,
 119                     },
 120                     Either::Right(ptr),
 121                 );
 122                 self.body.params.push(param_pat);
 123             }
 124
 125             for param in param_list.params() {
 126                 let pat = match param.pat() {
 127                     None => continue,
 128                     Some(pat) => pat,
 129                 };
 130                 let param_pat = self.collect_pat(pat);
 131                 self.body.params.push(param_pat);
 132             }
 133         };
 134
 135         self.body.body_expr = self.collect_expr_opt(body);
 136         (self.body, self.source_map)
 137     }
 138
 139     fn ctx(&self) -> LowerCtx {
 140         LowerCtx::new(self.db, self.expander.current_file_id)
 141     }
 142
 143     fn alloc_expr(&mut self, expr: Expr, ptr: AstPtr<ast::Expr>) -> ExprId {
 144         let src = self.expander.to_source(ptr);
 145         let id = self.make_expr(expr, Ok(src.clone()));
 146         self.source_map.expr_map.insert(src, id);
 147         id
 148     }
 149     // desugared exprs don't have ptr, that's wrong and should be fixed
 150     // somehow.
 151     fn alloc_expr_desugared(&mut self, expr: Expr) -> ExprId {
 152         self.make_expr(expr, Err(SyntheticSyntax))
 153     }
 154     fn unit(&mut self) -> ExprId {
 155         self.alloc_expr_desugared(Expr::Tuple { exprs: Vec::new() })
 156     }
 157     fn missing_expr(&mut self) -> ExprId {
 158         self.alloc_expr_desugared(Expr::Missing)
 159     }
 160     fn make_expr(&mut self, expr: Expr, src: Result<ExprSource, SyntheticSyntax>) -> ExprId {
 161         let id = self.body.exprs.alloc(expr);
 162         self.source_map.expr_map_back.insert(id, src);
 163         id
 164     }
 165
 166     fn alloc_pat(&mut self, pat: Pat, ptr: PatPtr) -> PatId {
 167         let src = self.expander.to_source(ptr);
 168         let id = self.make_pat(pat, Ok(src.clone()));
 169         self.source_map.pat_map.insert(src, id);
 170         id
 171     }
 172     fn missing_pat(&mut self) -> PatId {
 173         self.make_pat(Pat::Missing, Err(SyntheticSyntax))
 174     }
 175     fn make_pat(&mut self, pat: Pat, src: Result<PatSource, SyntheticSyntax>) -> PatId {
 176         let id = self.body.pats.alloc(pat);
 177         self.source_map.pat_map_back.insert(id, src);
 178         id
 179     }
 180
 181     fn alloc_label(&mut self, label: Label, ptr: AstPtr<ast::Label>) -> LabelId {
 182         let src = self.expander.to_source(ptr);
 183         let id = self.make_label(label, src.clone());
 184         self.source_map.label_map.insert(src, id);
 185         id
 186     }
 187     fn make_label(&mut self, label: Label, src: LabelSource) -> LabelId {
 188         let id = self.body.labels.alloc(label);
 189         self.source_map.label_map_back.insert(id, src);
 190         id
 191     }
 192
 193     fn collect_expr(&mut self, expr: ast::Expr) -> ExprId {
 194         let syntax_ptr = AstPtr::new(&expr);
 195         if self.check_cfg(&expr).is_none() {
 196             return self.missing_expr();
 197         }
 198
 199         match expr {
 200             ast::Expr::IfExpr(e) => {
 201                 let then_branch = self.collect_block_opt(e.then_branch());
 202
 203                 let else_branch = e.else_branch().map(|b| match b {
 204                     ast::ElseBranch::Block(it) => self.collect_block(it),
 205                     ast::ElseBranch::IfExpr(elif) => {
 206                         let expr: ast::Expr = ast::Expr::cast(elif.syntax().clone()).unwrap();
 207                         self.collect_expr(expr)
 208                     }
 209                 });
 210
 211                 let condition = match e.condition() {
 212                     None => self.missing_expr(),
 213                     Some(condition) => match condition.pat() {
 214                         None => self.collect_expr_opt(condition.expr()),
 215                         // if let -- desugar to match
 216                         Some(pat) => {
 217                             let pat = self.collect_pat(pat);
 218                             let match_expr = self.collect_expr_opt(condition.expr());
 219                             let placeholder_pat = self.missing_pat();
 220                             let arms = vec![
 221                                 MatchArm { pat, expr: then_branch, guard: None },
 222                                 MatchArm {
 223                                     pat: placeholder_pat,
 224                                     expr: else_branch.unwrap_or_else(|| self.unit()),
 225                                     guard: None,
 226                                 },
 227                             ];
 228                             return self
 229                                 .alloc_expr(Expr::Match { expr: match_expr, arms }, syntax_ptr);
 230                         }
 231                     },
 232                 };
 233
 234                 self.alloc_expr(Expr::If { condition, then_branch, else_branch }, syntax_ptr)
 235             }
 236             ast::Expr::EffectExpr(e) => match e.effect() {
 237                 ast::Effect::Try(_) => {
 238                     let body = self.collect_block_opt(e.block_expr());
 239                     self.alloc_expr(Expr::TryBlock { body }, syntax_ptr)
 240                 }
 241                 ast::Effect::Unsafe(_) => {
 242                     let body = self.collect_block_opt(e.block_expr());
 243                     self.alloc_expr(Expr::Unsafe { body }, syntax_ptr)
 244                 }
 245                 // FIXME: we need to record these effects somewhere...
 246                 ast::Effect::Label(label) => {
 247                     let label = self.collect_label(label);
 248                     match e.block_expr() {
 249                         Some(block) => {
 250                             let res = self.collect_block(block);
 251                             match &mut self.body.exprs[res] {
 252                                 Expr::Block { label: block_label, .. } => {
 253                                     *block_label = Some(label);
 254                                 }
 255                                 _ => unreachable!(),
 256                             }
 257                             res
 258                         }
 259                         None => self.missing_expr(),
 260                     }
 261                 }
 262                 // FIXME: we need to record these effects somewhere...
 263                 ast::Effect::Async(_) => {
 264                     let body = self.collect_block_opt(e.block_expr());
 265                     self.alloc_expr(Expr::Async { body }, syntax_ptr)
 266                 }
 267                 ast::Effect::Const(_) => {
 268                     let body = self.collect_block_opt(e.block_expr());
 269                     self.alloc_expr(Expr::Const { body }, syntax_ptr)
 270                 }
 271             },
 272             ast::Expr::BlockExpr(e) => self.collect_block(e),
 273             ast::Expr::LoopExpr(e) => {
 274                 let label = e.label().map(|label| self.collect_label(label));
 275                 let body = self.collect_block_opt(e.loop_body());
 276                 self.alloc_expr(Expr::Loop { body, label }, syntax_ptr)
 277             }
 278             ast::Expr::WhileExpr(e) => {
 279                 let label = e.label().map(|label| self.collect_label(label));
 280                 let body = self.collect_block_opt(e.loop_body());
 281
 282                 let condition = match e.condition() {
 283                     None => self.missing_expr(),
 284                     Some(condition) => match condition.pat() {
 285                         None => self.collect_expr_opt(condition.expr()),
 286                         // if let -- desugar to match
 287                         Some(pat) => {
 288                             cov_mark::hit!(infer_resolve_while_let);
 289                             let pat = self.collect_pat(pat);
 290                             let match_expr = self.collect_expr_opt(condition.expr());
 291                             let placeholder_pat = self.missing_pat();
 292                             let break_ =
 293                                 self.alloc_expr_desugared(Expr::Break { expr: None, label: None });
 294                             let arms = vec![
 295                                 MatchArm { pat, expr: body, guard: None },
 296                                 MatchArm { pat: placeholder_pat, expr: break_, guard: None },
 297                             ];
 298                             let match_expr =
 299                                 self.alloc_expr_desugared(Expr::Match { expr: match_expr, arms });
 300                             return self
 301                                 .alloc_expr(Expr::Loop { body: match_expr, label }, syntax_ptr);
 302                         }
 303                     },
 304                 };
 305
 306                 self.alloc_expr(Expr::While { condition, body, label }, syntax_ptr)
 307             }
 308             ast::Expr::ForExpr(e) => {
 309                 let label = e.label().map(|label| self.collect_label(label));
 310                 let iterable = self.collect_expr_opt(e.iterable());
 311                 let pat = self.collect_pat_opt(e.pat());
 312                 let body = self.collect_block_opt(e.loop_body());
 313                 self.alloc_expr(Expr::For { iterable, pat, body, label }, syntax_ptr)
 314             }
 315             ast::Expr::CallExpr(e) => {
 316                 let callee = self.collect_expr_opt(e.expr());
 317                 let args = if let Some(arg_list) = e.arg_list() {
 318                     arg_list.args().map(|e| self.collect_expr(e)).collect()
 319                 } else {
 320                     Vec::new()
 321                 };
 322                 self.alloc_expr(Expr::Call { callee, args }, syntax_ptr)
 323             }
 324             ast::Expr::MethodCallExpr(e) => {
 325                 let receiver = self.collect_expr_opt(e.receiver());
 326                 let args = if let Some(arg_list) = e.arg_list() {
 327                     arg_list.args().map(|e| self.collect_expr(e)).collect()
 328                 } else {
 329                     Vec::new()
 330                 };
 331                 let method_name = e.name_ref().map(|nr| nr.as_name()).unwrap_or_else(Name::missing);
 332                 let generic_args =
 333                     e.generic_arg_list().and_then(|it| GenericArgs::from_ast(&self.ctx(), it));
 334                 self.alloc_expr(
 335                     Expr::MethodCall { receiver, method_name, args, generic_args },
 336                     syntax_ptr,
 337                 )
 338             }
 339             ast::Expr::MatchExpr(e) => {
 340                 let expr = self.collect_expr_opt(e.expr());
 341                 let arms = if let Some(match_arm_list) = e.match_arm_list() {
 342                     match_arm_list
 343                         .arms()
 344                         .filter_map(|arm| {
 345                             self.check_cfg(&arm).map(|()| MatchArm {
 346                                 pat: self.collect_pat_opt(arm.pat()),
 347                                 expr: self.collect_expr_opt(arm.expr()),
 348                                 guard: arm
 349                                     .guard()
 350                                     .and_then(|guard| guard.expr())
 351                                     .map(|e| self.collect_expr(e)),
 352                             })
 353                         })
 354                         .collect()
 355                 } else {
 356                     Vec::new()
 357                 };
 358                 self.alloc_expr(Expr::Match { expr, arms }, syntax_ptr)
 359             }
 360             ast::Expr::PathExpr(e) => {
 361                 let path = e
 362                     .path()
 363                     .and_then(|path| self.expander.parse_path(path))
 364                     .map(Expr::Path)
 365                     .unwrap_or(Expr::Missing);
 366                 self.alloc_expr(path, syntax_ptr)
 367             }
 368             ast::Expr::ContinueExpr(e) => self.alloc_expr(
 369                 Expr::Continue { label: e.lifetime().map(|l| Name::new_lifetime(&l)) },
 370                 syntax_ptr,
 371             ),
 372             ast::Expr::BreakExpr(e) => {
 373                 let expr = e.expr().map(|e| self.collect_expr(e));
 374                 self.alloc_expr(
 375                     Expr::Break { expr, label: e.lifetime().map(|l| Name::new_lifetime(&l)) },
 376                     syntax_ptr,
 377                 )
 378             }
 379             ast::Expr::ParenExpr(e) => {
 380                 let inner = self.collect_expr_opt(e.expr());
 381                 // make the paren expr point to the inner expression as well
 382                 let src = self.expander.to_source(syntax_ptr);
 383                 self.source_map.expr_map.insert(src, inner);
 384                 inner
 385             }
 386             ast::Expr::ReturnExpr(e) => {
 387                 let expr = e.expr().map(|e| self.collect_expr(e));
 388                 self.alloc_expr(Expr::Return { expr }, syntax_ptr)
 389             }
 390             ast::Expr::YieldExpr(e) => {
 391                 let expr = e.expr().map(|e| self.collect_expr(e));
 392                 self.alloc_expr(Expr::Yield { expr }, syntax_ptr)
 393             }
 394             ast::Expr::RecordExpr(e) => {
 395                 let path = e.path().and_then(|path| self.expander.parse_path(path));
 396                 let mut field_ptrs = Vec::new();
 397                 let record_lit = if let Some(nfl) = e.record_expr_field_list() {
 398                     let fields = nfl
 399                         .fields()
 400                         .inspect(|field| field_ptrs.push(AstPtr::new(field)))
 401                         .filter_map(|field| {
 402                             self.check_cfg(&field)?;
 403
 404                             let name = field.field_name()?.as_name();
 405
 406                             Some(RecordLitField {
 407                                 name,
 408                                 expr: match field.expr() {
 409                                     Some(e) => self.collect_expr(e),
 410                                     None => self.missing_expr(),
 411                                 },
 412                             })
 413                         })
 414                         .collect();
 415                     let spread = nfl.spread().map(|s| self.collect_expr(s));
 416                     Expr::RecordLit { path, fields, spread }
 417                 } else {
 418                     Expr::RecordLit { path, fields: Vec::new(), spread: None }
 419                 };
 420
 421                 let res = self.alloc_expr(record_lit, syntax_ptr);
 422                 for (i, ptr) in field_ptrs.into_iter().enumerate() {
 423                     let src = self.expander.to_source(ptr);
 424                     self.source_map.field_map.insert((res, i), src);
 425                 }
 426                 res
 427             }
 428             ast::Expr::FieldExpr(e) => {
 429                 let expr = self.collect_expr_opt(e.expr());
 430                 let name = match e.field_access() {
 431                     Some(kind) => kind.as_name(),
 432                     _ => Name::missing(),
 433                 };
 434                 self.alloc_expr(Expr::Field { expr, name }, syntax_ptr)
 435             }
 436             ast::Expr::AwaitExpr(e) => {
 437                 let expr = self.collect_expr_opt(e.expr());
 438                 self.alloc_expr(Expr::Await { expr }, syntax_ptr)
 439             }
 440             ast::Expr::TryExpr(e) => {
 441                 let expr = self.collect_expr_opt(e.expr());
 442                 self.alloc_expr(Expr::Try { expr }, syntax_ptr)
 443             }
 444             ast::Expr::CastExpr(e) => {
 445                 let expr = self.collect_expr_opt(e.expr());
 446                 let type_ref = TypeRef::from_ast_opt(&self.ctx(), e.ty());
 447                 self.alloc_expr(Expr::Cast { expr, type_ref }, syntax_ptr)
 448             }
 449             ast::Expr::RefExpr(e) => {
 450                 let expr = self.collect_expr_opt(e.expr());
 451                 let raw_tok = e.raw_token().is_some();
 452                 let mutability = if raw_tok {
 453                     if e.mut_token().is_some() {
 454                         Mutability::Mut
 455                     } else if e.const_token().is_some() {
 456                         Mutability::Shared
 457                     } else {
 458                         unreachable!("parser only remaps to raw_token() if matching mutability token follows")
 459                     }
 460                 } else {
 461                     Mutability::from_mutable(e.mut_token().is_some())
 462                 };
 463                 let rawness = Rawness::from_raw(raw_tok);
 464                 self.alloc_expr(Expr::Ref { expr, rawness, mutability }, syntax_ptr)
 465             }
 466             ast::Expr::PrefixExpr(e) => {
 467                 let expr = self.collect_expr_opt(e.expr());
 468                 if let Some(op) = e.op_kind() {
 469                     self.alloc_expr(Expr::UnaryOp { expr, op }, syntax_ptr)
 470                 } else {
 471                     self.alloc_expr(Expr::Missing, syntax_ptr)
 472                 }
 473             }
 474             ast::Expr::ClosureExpr(e) => {
 475                 let mut args = Vec::new();
 476                 let mut arg_types = Vec::new();
 477                 if let Some(pl) = e.param_list() {
 478                     for param in pl.params() {
 479                         let pat = self.collect_pat_opt(param.pat());
 480                         let type_ref = param.ty().map(|it| TypeRef::from_ast(&self.ctx(), it));
 481                         args.push(pat);
 482                         arg_types.push(type_ref);
 483                     }
 484                 }
 485                 let ret_type =
 486                     e.ret_type().and_then(|r| r.ty()).map(|it| TypeRef::from_ast(&self.ctx(), it));
 487                 let body = self.collect_expr_opt(e.body());
 488                 self.alloc_expr(Expr::Lambda { args, arg_types, ret_type, body }, syntax_ptr)
 489             }
 490             ast::Expr::BinExpr(e) => {
 491                 let lhs = self.collect_expr_opt(e.lhs());
 492                 let rhs = self.collect_expr_opt(e.rhs());
 493                 let op = e.op_kind().map(BinaryOp::from);
 494                 self.alloc_expr(Expr::BinaryOp { lhs, rhs, op }, syntax_ptr)
 495             }
 496             ast::Expr::TupleExpr(e) => {
 497                 let exprs = e.fields().map(|expr| self.collect_expr(expr)).collect();
 498                 self.alloc_expr(Expr::Tuple { exprs }, syntax_ptr)
 499             }
 500             ast::Expr::BoxExpr(e) => {
 501                 let expr = self.collect_expr_opt(e.expr());
 502                 self.alloc_expr(Expr::Box { expr }, syntax_ptr)
 503             }
 504
 505             ast::Expr::ArrayExpr(e) => {
 506                 let kind = e.kind();
 507
 508                 match kind {
 509                     ArrayExprKind::ElementList(e) => {
 510                         let exprs = e.map(|expr| self.collect_expr(expr)).collect();
 511                         self.alloc_expr(Expr::Array(Array::ElementList(exprs)), syntax_ptr)
 512                     }
 513                     ArrayExprKind::Repeat { initializer, repeat } => {
 514                         let initializer = self.collect_expr_opt(initializer);
 515                         let repeat = self.collect_expr_opt(repeat);
 516                         self.alloc_expr(
 517                             Expr::Array(Array::Repeat { initializer, repeat }),
 518                             syntax_ptr,
 519                         )
 520                     }
 521                 }
 522             }
 523
 524             ast::Expr::Literal(e) => self.alloc_expr(Expr::Literal(e.kind().into()), syntax_ptr),
 525             ast::Expr::IndexExpr(e) => {
 526                 let base = self.collect_expr_opt(e.base());
 527                 let index = self.collect_expr_opt(e.index());
 528                 self.alloc_expr(Expr::Index { base, index }, syntax_ptr)
 529             }
 530             ast::Expr::RangeExpr(e) => {
 531                 let lhs = e.start().map(|lhs| self.collect_expr(lhs));
 532                 let rhs = e.end().map(|rhs| self.collect_expr(rhs));
 533                 match e.op_kind() {
 534                     Some(range_type) => {
 535                         self.alloc_expr(Expr::Range { lhs, rhs, range_type }, syntax_ptr)
 536                     }
 537                     None => self.alloc_expr(Expr::Missing, syntax_ptr),
 538                 }
 539             }
 540             ast::Expr::MacroCall(e) => {
 541                 let mut ids = vec![];
 542                 self.collect_macro_call(e, syntax_ptr.clone(), |this, expansion| {
 543                     ids.push(match expansion {
 544                         Some(it) => this.collect_expr(it),
 545                         None => this.alloc_expr(Expr::Missing, syntax_ptr.clone()),
 546                     })
 547                 });
 548                 ids[0]
 549             }
 550         }
 551     }
 552
 553     fn collect_macro_call<F: FnMut(&mut Self, Option<T>), T: ast::AstNode>(
 554         &mut self,
 555         e: ast::MacroCall,
 556         syntax_ptr: AstPtr<ast::Expr>,
 557         mut collector: F,
 558     ) {
 559         // File containing the macro call. Expansion errors will be attached here.
 560         let outer_file = self.expander.current_file_id;
 561
 562         let macro_call = self.expander.to_source(AstPtr::new(&e));
 563         let res = self.expander.enter_expand(self.db, e);
 564
 565         match &res.err {
 566             Some(ExpandError::UnresolvedProcMacro) => {
 567                 self.source_map.diagnostics.push(BodyDiagnostic::UnresolvedProcMacro(
 568                     UnresolvedProcMacro {
 569                         file: outer_file,
 570                         node: syntax_ptr.into(),
 571                         precise_location: None,
 572                         macro_name: None,
 573                     },
 574                 ));
 575             }
 576             Some(err) => {
 577                 self.source_map.diagnostics.push(BodyDiagnostic::MacroError(MacroError {
 578                     file: outer_file,
 579                     node: syntax_ptr.into(),
 580                     message: err.to_string(),
 581                 }));
 582             }
 583             None => {}
 584         }
 585
 586         match res.value {
 587             Some((mark, expansion)) => {
 588                 // FIXME: Statements are too complicated to recover from error for now.
 589                 // It is because we don't have any hygiene for local variable expansion right now.
 590                 if T::can_cast(syntax::SyntaxKind::MACRO_STMTS) && res.err.is_some() {
 591                     self.expander.exit(self.db, mark);
 592                     collector(self, None);
 593                 } else {
 594                     self.source_map.expansions.insert(macro_call, self.expander.current_file_id);
 595
 596                     let item_tree = self.db.item_tree(self.expander.current_file_id);
 597                     self.item_trees.insert(self.expander.current_file_id, item_tree);
 598
 599                     let id = collector(self, Some(expansion));
 600                     self.expander.exit(self.db, mark);
 601                     id
 602                 }
 603             }
 604             None => collector(self, None),
 605         }
 606     }
 607
 608     fn find_inner_item<N: ItemTreeNode>(&self, ast: &N::Source) -> Option<ItemTreeId<N>> {
 609         let id = self.expander.ast_id(ast);
 610         let tree = &self.item_trees[&id.file_id];
 611
 612         // FIXME: This probably breaks with `use` items, since they produce multiple item tree nodes
 613
 614         // Root file (non-macro).
 615         let item_tree_id = tree
 616             .all_inner_items()
 617             .chain(tree.top_level_items().iter().copied())
 618             .filter_map(|mod_item| mod_item.downcast::<N>())
 619             .find(|tree_id| tree[*tree_id].ast_id().upcast() == id.value.upcast())
 620             .or_else(|| {
 621                 log::debug!(
 622                     "couldn't find inner {} item for {:?} (AST: `{}` - {:?})",
 623                     type_name::<N>(),
 624                     id,
 625                     ast.syntax(),
 626                     ast.syntax(),
 627                 );
 628                 None
 629             })?;
 630
 631         Some(ItemTreeId::new(id.file_id, item_tree_id))
 632     }
 633
 634     fn collect_expr_opt(&mut self, expr: Option<ast::Expr>) -> ExprId {
 635         if let Some(expr) = expr {
 636             self.collect_expr(expr)
 637         } else {
 638             self.missing_expr()
 639         }
 640     }
 641
 642     fn collect_stmt(&mut self, s: ast::Stmt) -> Option<Vec<Statement>> {
 643         let stmt =
 644             match s {
 645                 ast::Stmt::LetStmt(stmt) => {
 646                     self.check_cfg(&stmt)?;
 647
 648                     let pat = self.collect_pat_opt(stmt.pat());
 649                     let type_ref = stmt.ty().map(|it| TypeRef::from_ast(&self.ctx(), it));
 650                     let initializer = stmt.initializer().map(|e| self.collect_expr(e));
 651                     vec![Statement::Let { pat, type_ref, initializer }]
 652                 }
 653                 ast::Stmt::ExprStmt(stmt) => {
 654                     self.check_cfg(&stmt)?;
 655
 656                     // Note that macro could be expended to multiple statements
 657                     if let Some(ast::Expr::MacroCall(m)) = stmt.expr() {
 658                         let syntax_ptr = AstPtr::new(&stmt.expr().unwrap());
 659                         let mut stmts = vec![];
 660
 661                         self.collect_macro_call(m, syntax_ptr.clone(), |this, expansion| {
 662                             match expansion {
 663                                 Some(expansion) => {
 664                                     let statements: ast::MacroStmts = expansion;
 665                                     this.collect_stmts_items(statements.statements());
 666
 667                                     statements.statements().for_each(|stmt| {
 668                                         if let Some(mut r) = this.collect_stmt(stmt) {
 669                                             stmts.append(&mut r);
 670                                         }
 671                                     });
 672                                     if let Some(expr) = statements.expr() {
 673                                         stmts.push(Statement::Expr(this.collect_expr(expr)));
 674                                     }
 675                                 }
 676                                 None => {
 677                                     stmts.push(Statement::Expr(
 678                                         this.alloc_expr(Expr::Missing, syntax_ptr.clone()),
 679                                     ));
 680                                 }
 681                             }
 682                         });
 683                         stmts
 684                     } else {
 685                         vec![Statement::Expr(self.collect_expr_opt(stmt.expr()))]
 686                     }
 687                 }
 688                 ast::Stmt::Item(item) => {
 689                     self.check_cfg(&item)?;
 690
 691                     return None;
 692                 }
 693             };
 694
 695         Some(stmt)
 696     }
 697
 698     fn collect_block(&mut self, block: ast::BlockExpr) -> ExprId {
 699         let ast_id = self.expander.ast_id(&block);
 700         let block_loc =
 701             BlockLoc { ast_id, module: self.expander.def_map.module_id(self.expander.module) };
 702         let block_id = self.db.intern_block(block_loc);
 703         let opt_def_map = self.db.block_def_map(block_id);
 704         let has_def_map = opt_def_map.is_some();
 705         let def_map = opt_def_map.unwrap_or_else(|| self.expander.def_map.clone());
 706         let module = if has_def_map { def_map.root() } else { self.expander.module };
 707         let prev_def_map = mem::replace(&mut self.expander.def_map, def_map);
 708         let prev_local_module = mem::replace(&mut self.expander.module, module);
 709
 710         self.collect_stmts_items(block.statements());
 711         let statements =
 712             block.statements().filter_map(|s| self.collect_stmt(s)).flatten().collect();
 713         let tail = block.tail_expr().map(|e| self.collect_expr(e));
 714         let syntax_node_ptr = AstPtr::new(&block.into());
 715         let expr_id = self.alloc_expr(
 716             Expr::Block { id: block_id, statements, tail, label: None },
 717             syntax_node_ptr,
 718         );
 719
 720         self.expander.def_map = prev_def_map;
 721         self.expander.module = prev_local_module;
 722         expr_id
 723     }
 724
 725     fn collect_stmts_items(&mut self, stmts: ast::AstChildren<ast::Stmt>) {
 726         let container = ContainerId::DefWithBodyId(self.def);
 727
 728         let items = stmts
 729             .filter_map(|stmt| match stmt {
 730                 ast::Stmt::Item(it) => Some(it),
 731                 ast::Stmt::LetStmt(_) | ast::Stmt::ExprStmt(_) => None,
 732             })
 733             .filter_map(|item| {
 734                 let (def, name): (ModuleDefId, Option<ast::Name>) = match item {
 735                     ast::Item::Fn(def) => {
 736                         let id = self.find_inner_item(&def)?;
 737                         (
 738                             FunctionLoc { container: container.into(), id }.intern(self.db).into(),
 739                             def.name(),
 740                         )
 741                     }
 742                     ast::Item::TypeAlias(def) => {
 743                         let id = self.find_inner_item(&def)?;
 744                         (
 745                             TypeAliasLoc { container: container.into(), id }.intern(self.db).into(),
 746                             def.name(),
 747                         )
 748                     }
 749                     ast::Item::Const(def) => {
 750                         let id = self.find_inner_item(&def)?;
 751                         (
 752                             ConstLoc { container: container.into(), id }.intern(self.db).into(),
 753                             def.name(),
 754                         )
 755                     }
 756                     ast::Item::Static(def) => {
 757                         let id = self.find_inner_item(&def)?;
 758                         (StaticLoc { container, id }.intern(self.db).into(), def.name())
 759                     }
 760                     ast::Item::Struct(def) => {
 761                         let id = self.find_inner_item(&def)?;
 762                         (StructLoc { container, id }.intern(self.db).into(), def.name())
 763                     }
 764                     ast::Item::Enum(def) => {
 765                         let id = self.find_inner_item(&def)?;
 766                         (EnumLoc { container, id }.intern(self.db).into(), def.name())
 767                     }
 768                     ast::Item::Union(def) => {
 769                         let id = self.find_inner_item(&def)?;
 770                         (UnionLoc { container, id }.intern(self.db).into(), def.name())
 771                     }
 772                     ast::Item::Trait(def) => {
 773                         let id = self.find_inner_item(&def)?;
 774                         (TraitLoc { container, id }.intern(self.db).into(), def.name())
 775                     }
 776                     ast::Item::ExternBlock(_) => return None, // FIXME: collect from extern blocks
 777                     ast::Item::Impl(_)
 778                     | ast::Item::Use(_)
 779                     | ast::Item::ExternCrate(_)
 780                     | ast::Item::Module(_)
 781                     | ast::Item::MacroCall(_) => return None,
 782                     ast::Item::MacroRules(def) => {
 783                         return Some(Either::Right(ast::Macro::from(def)));
 784                     }
 785                     ast::Item::MacroDef(def) => {
 786                         return Some(Either::Right(ast::Macro::from(def)));
 787                     }
 788                 };
 789
 790                 Some(Either::Left((def, name)))
 791             })
 792             .collect::<Vec<_>>();
 793
 794         for either in items {
 795             match either {
 796                 Either::Left((def, name)) => {
 797                     self.body.item_scope.define_def(def);
 798                     if let Some(name) = name {
 799                         let vis = crate::visibility::Visibility::Public; // FIXME determine correctly
 800                         let has_constructor = match def {
 801                             ModuleDefId::AdtId(AdtId::StructId(s)) => {
 802                                 self.db.struct_data(s).variant_data.kind() != StructKind::Record
 803                             }
 804                             _ => true,
 805                         };
 806                         self.body.item_scope.push_res(
 807                             name.as_name(),
 808                             crate::per_ns::PerNs::from_def(def, vis, has_constructor),
 809                         );
 810                     }
 811                 }
 812                 Either::Right(e) => {
 813                     let mac = MacroDefId {
 814                         krate: self.expander.def_map.krate(),
 815                         ast_id: Some(self.expander.ast_id(&e)),
 816                         kind: MacroDefKind::Declarative,
 817                         local_inner: false,
 818                     };
 819                     if let Some(name) = e.name() {
 820                         self.body.item_scope.define_legacy_macro(name.as_name(), mac);
 821                     }
 822                 }
 823             }
 824         }
 825     }
 826
 827     fn collect_block_opt(&mut self, expr: Option<ast::BlockExpr>) -> ExprId {
 828         if let Some(block) = expr {
 829             self.collect_block(block)
 830         } else {
 831             self.missing_expr()
 832         }
 833     }
 834
 835     fn collect_label(&mut self, ast_label: ast::Label) -> LabelId {
 836         let label = Label {
 837             name: ast_label.lifetime().as_ref().map_or_else(Name::missing, Name::new_lifetime),
 838         };
 839         self.alloc_label(label, AstPtr::new(&ast_label))
 840     }
 841
 842     fn collect_pat(&mut self, pat: ast::Pat) -> PatId {
 843         let pattern = match &pat {
 844             ast::Pat::IdentPat(bp) => {
 845                 let name = bp.name().map(|nr| nr.as_name()).unwrap_or_else(Name::missing);
 846                 let annotation =
 847                     BindingAnnotation::new(bp.mut_token().is_some(), bp.ref_token().is_some());
 848                 let subpat = bp.pat().map(|subpat| self.collect_pat(subpat));
 849                 if annotation == BindingAnnotation::Unannotated && subpat.is_none() {
 850                     // This could also be a single-segment path pattern. To
 851                     // decide that, we need to try resolving the name.
 852                     let (resolved, _) = self.expander.def_map.resolve_path(
 853                         self.db,
 854                         self.expander.module,
 855                         &name.clone().into(),
 856                         BuiltinShadowMode::Other,
 857                     );
 858                     match resolved.take_values() {
 859                         Some(ModuleDefId::ConstId(_)) => Pat::Path(name.into()),
 860                         Some(ModuleDefId::EnumVariantId(_)) => {
 861                             // this is only really valid for unit variants, but
 862                             // shadowing other enum variants with a pattern is
 863                             // an error anyway
 864                             Pat::Path(name.into())
 865                         }
 866                         Some(ModuleDefId::AdtId(AdtId::StructId(s)))
 867                             if self.db.struct_data(s).variant_data.kind() != StructKind::Record =>
 868                         {
 869                             // Funnily enough, record structs *can* be shadowed
 870                             // by pattern bindings (but unit or tuple structs
 871                             // can't).
 872                             Pat::Path(name.into())
 873                         }
 874                         // shadowing statics is an error as well, so we just ignore that case here
 875                         _ => Pat::Bind { name, mode: annotation, subpat },
 876                     }
 877                 } else {
 878                     Pat::Bind { name, mode: annotation, subpat }
 879                 }
 880             }
 881             ast::Pat::TupleStructPat(p) => {
 882                 let path = p.path().and_then(|path| self.expander.parse_path(path));
 883                 let (args, ellipsis) = self.collect_tuple_pat(p.fields());
 884                 Pat::TupleStruct { path, args, ellipsis }
 885             }
 886             ast::Pat::RefPat(p) => {
 887                 let pat = self.collect_pat_opt(p.pat());
 888                 let mutability = Mutability::from_mutable(p.mut_token().is_some());
 889                 Pat::Ref { pat, mutability }
 890             }
 891             ast::Pat::PathPat(p) => {
 892                 let path = p.path().and_then(|path| self.expander.parse_path(path));
 893                 path.map(Pat::Path).unwrap_or(Pat::Missing)
 894             }
 895             ast::Pat::OrPat(p) => {
 896                 let pats = p.pats().map(|p| self.collect_pat(p)).collect();
 897                 Pat::Or(pats)
 898             }
 899             ast::Pat::ParenPat(p) => return self.collect_pat_opt(p.pat()),
 900             ast::Pat::TuplePat(p) => {
 901                 let (args, ellipsis) = self.collect_tuple_pat(p.fields());
 902                 Pat::Tuple { args, ellipsis }
 903             }
 904             ast::Pat::WildcardPat(_) => Pat::Wild,
 905             ast::Pat::RecordPat(p) => {
 906                 let path = p.path().and_then(|path| self.expander.parse_path(path));
 907                 let args: Vec<_> = p
 908                     .record_pat_field_list()
 909                     .expect("every struct should have a field list")
 910                     .fields()
 911                     .filter_map(|f| {
 912                         let ast_pat = f.pat()?;
 913                         let pat = self.collect_pat(ast_pat);
 914                         let name = f.field_name()?.as_name();
 915                         Some(RecordFieldPat { name, pat })
 916                     })
 917                     .collect();
 918
 919                 let ellipsis = p
 920                     .record_pat_field_list()
 921                     .expect("every struct should have a field list")
 922                     .dotdot_token()
 923                     .is_some();
 924
 925                 Pat::Record { path, args, ellipsis }
 926             }
 927             ast::Pat::SlicePat(p) => {
 928                 let SlicePatComponents { prefix, slice, suffix } = p.components();
 929
 930                 // FIXME properly handle `RestPat`
 931                 Pat::Slice {
 932                     prefix: prefix.into_iter().map(|p| self.collect_pat(p)).collect(),
 933                     slice: slice.map(|p| self.collect_pat(p)),
 934                     suffix: suffix.into_iter().map(|p| self.collect_pat(p)).collect(),
 935                 }
 936             }
 937             ast::Pat::LiteralPat(lit) => {
 938                 if let Some(ast_lit) = lit.literal() {
 939                     let expr = Expr::Literal(ast_lit.kind().into());
 940                     let expr_ptr = AstPtr::new(&ast::Expr::Literal(ast_lit));
 941                     let expr_id = self.alloc_expr(expr, expr_ptr);
 942                     Pat::Lit(expr_id)
 943                 } else {
 944                     Pat::Missing
 945                 }
 946             }
 947             ast::Pat::RestPat(_) => {
 948                 // `RestPat` requires special handling and should not be mapped
 949                 // to a Pat. Here we are using `Pat::Missing` as a fallback for
 950                 // when `RestPat` is mapped to `Pat`, which can easily happen
 951                 // when the source code being analyzed has a malformed pattern
 952                 // which includes `..` in a place where it isn't valid.
 953
 954                 Pat::Missing
 955             }
 956             ast::Pat::BoxPat(boxpat) => {
 957                 let inner = self.collect_pat_opt(boxpat.pat());
 958                 Pat::Box { inner }
 959             }
 960             ast::Pat::ConstBlockPat(const_block_pat) => {
 961                 if let Some(expr) = const_block_pat.block_expr() {
 962                     let expr_id = self.collect_block(expr);
 963                     Pat::ConstBlock(expr_id)
 964                 } else {
 965                     Pat::Missing
 966                 }
 967             }
 968             // FIXME: implement
 969             ast::Pat::RangePat(_) | ast::Pat::MacroPat(_) => Pat::Missing,
 970         };
 971         let ptr = AstPtr::new(&pat);
 972         self.alloc_pat(pattern, Either::Left(ptr))
 973     }
 974
 975     fn collect_pat_opt(&mut self, pat: Option<ast::Pat>) -> PatId {
 976         if let Some(pat) = pat {
 977             self.collect_pat(pat)
 978         } else {
 979             self.missing_pat()
 980         }
 981     }
 982
 983     fn collect_tuple_pat(&mut self, args: AstChildren<ast::Pat>) -> (Vec<PatId>, Option<usize>) {
 984         // Find the location of the `..`, if there is one. Note that we do not
 985         // consider the possibility of there being multiple `..` here.
 986         let ellipsis = args.clone().position(|p| matches!(p, ast::Pat::RestPat(_)));
 987         // We want to skip the `..` pattern here, since we account for it above.
 988         let args = args
 989             .filter(|p| !matches!(p, ast::Pat::RestPat(_)))
 990             .map(|p| self.collect_pat(p))
 991             .collect();
 992
 993         (args, ellipsis)
 994     }
 995
 996     /// Returns `None` (and emits diagnostics) when `owner` if `#[cfg]`d out, and `Some(())` when
 997     /// not.
 998     fn check_cfg(&mut self, owner: &dyn ast::AttrsOwner) -> Option<()> {
 999         match self.expander.parse_attrs(self.db, owner).cfg() {
1000             Some(cfg) => {
1001                 if self.expander.cfg_options().check(&cfg) != Some(false) {
1002                     return Some(());
1003                 }
1004
1005                 self.source_map.diagnostics.push(BodyDiagnostic::InactiveCode(InactiveCode {
1006                     file: self.expander.current_file_id,
1007                     node: SyntaxNodePtr::new(owner.syntax()),
1008                     cfg,
1009                     opts: self.expander.cfg_options().clone(),
1010                 }));
1011
1012                 None
1013             }
1014             None => Some(()),
1015         }
1016     }
1017 }
1018
1019 impl From<ast::BinOp> for BinaryOp {
1020     fn from(ast_op: ast::BinOp) -> Self {
1021         match ast_op {
1022             ast::BinOp::BooleanOr => BinaryOp::LogicOp(LogicOp::Or),
1023             ast::BinOp::BooleanAnd => BinaryOp::LogicOp(LogicOp::And),
1024             ast::BinOp::EqualityTest => BinaryOp::CmpOp(CmpOp::Eq { negated: false }),
1025             ast::BinOp::NegatedEqualityTest => BinaryOp::CmpOp(CmpOp::Eq { negated: true }),
1026             ast::BinOp::LesserEqualTest => {
1027                 BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Less, strict: false })
1028             }
1029             ast::BinOp::GreaterEqualTest => {
1030                 BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Greater, strict: false })
1031             }
1032             ast::BinOp::LesserTest => {
1033                 BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Less, strict: true })
1034             }
1035             ast::BinOp::GreaterTest => {
1036                 BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Greater, strict: true })
1037             }
1038             ast::BinOp::Addition => BinaryOp::ArithOp(ArithOp::Add),
1039             ast::BinOp::Multiplication => BinaryOp::ArithOp(ArithOp::Mul),
1040             ast::BinOp::Subtraction => BinaryOp::ArithOp(ArithOp::Sub),
1041             ast::BinOp::Division => BinaryOp::ArithOp(ArithOp::Div),
1042             ast::BinOp::Remainder => BinaryOp::ArithOp(ArithOp::Rem),
1043             ast::BinOp::LeftShift => BinaryOp::ArithOp(ArithOp::Shl),
1044             ast::BinOp::RightShift => BinaryOp::ArithOp(ArithOp::Shr),
1045             ast::BinOp::BitwiseXor => BinaryOp::ArithOp(ArithOp::BitXor),
1046             ast::BinOp::BitwiseOr => BinaryOp::ArithOp(ArithOp::BitOr),
1047             ast::BinOp::BitwiseAnd => BinaryOp::ArithOp(ArithOp::BitAnd),
1048             ast::BinOp::Assignment => BinaryOp::Assignment { op: None },
1049             ast::BinOp::AddAssign => BinaryOp::Assignment { op: Some(ArithOp::Add) },
1050             ast::BinOp::DivAssign => BinaryOp::Assignment { op: Some(ArithOp::Div) },
1051             ast::BinOp::MulAssign => BinaryOp::Assignment { op: Some(ArithOp::Mul) },
1052             ast::BinOp::RemAssign => BinaryOp::Assignment { op: Some(ArithOp::Rem) },
1053             ast::BinOp::ShlAssign => BinaryOp::Assignment { op: Some(ArithOp::Shl) },
1054             ast::BinOp::ShrAssign => BinaryOp::Assignment { op: Some(ArithOp::Shr) },
1055             ast::BinOp::SubAssign => BinaryOp::Assignment { op: Some(ArithOp::Sub) },
1056             ast::BinOp::BitOrAssign => BinaryOp::Assignment { op: Some(ArithOp::BitOr) },
1057             ast::BinOp::BitAndAssign => BinaryOp::Assignment { op: Some(ArithOp::BitAnd) },
1058             ast::BinOp::BitXorAssign => BinaryOp::Assignment { op: Some(ArithOp::BitXor) },
1059         }
1060     }
1061 }
1062
1063 impl From<ast::LiteralKind> for Literal {
1064     fn from(ast_lit_kind: ast::LiteralKind) -> Self {
1065         match ast_lit_kind {
1066             LiteralKind::IntNumber(lit) => {
1067                 if let builtin @ Some(_) = lit.suffix().and_then(BuiltinFloat::from_suffix) {
1068                     return Literal::Float(Default::default(), builtin);
1069                 } else if let builtin @ Some(_) =
1070                     lit.suffix().and_then(|it| BuiltinInt::from_suffix(&it))
1071                 {
1072                     Literal::Int(Default::default(), builtin)
1073                 } else {
1074                     let builtin = lit.suffix().and_then(|it| BuiltinUint::from_suffix(&it));
1075                     Literal::Uint(Default::default(), builtin)
1076                 }
1077             }
1078             LiteralKind::FloatNumber(lit) => {
1079                 let ty = lit.suffix().and_then(|it| BuiltinFloat::from_suffix(&it));
1080                 Literal::Float(Default::default(), ty)
1081             }
1082             LiteralKind::ByteString(_) => Literal::ByteString(Default::default()),
1083             LiteralKind::String(_) => Literal::String(Default::default()),
1084             LiteralKind::Byte => Literal::Uint(Default::default(), Some(BuiltinUint::U8)),
1085             LiteralKind::Bool(val) => Literal::Bool(val),
1086             LiteralKind::Char => Literal::Char(Default::default()),
1087         }
1088     }
1089 }