rust/crates/hir_def/src/body/lower.rs
2021-06-21 16:40:21 +02:00

1027 lines
43 KiB
Rust

//! Transforms `ast::Expr` into an equivalent `hir_def::expr::Expr`
//! representation.
use std::{mem, sync::Arc};
use either::Either;
use hir_expand::{
ast_id_map::{AstIdMap, FileAstId},
hygiene::Hygiene,
name::{name, AsName, Name},
ExpandError, HirFileId, InFile,
};
use la_arena::Arena;
use profile::Count;
use syntax::{
ast::{
self, ArgListOwner, ArrayExprKind, AstChildren, LiteralKind, LoopBodyOwner, NameOwner,
SlicePatComponents,
},
AstNode, AstPtr, SyntaxNodePtr,
};
use crate::{
adt::StructKind,
body::{Body, BodySourceMap, Expander, LabelSource, PatPtr, SyntheticSyntax},
body::{BodyDiagnostic, ExprSource, PatSource},
builtin_type::{BuiltinFloat, BuiltinInt, BuiltinUint},
db::DefDatabase,
expr::{
dummy_expr_id, ArithOp, Array, BinaryOp, BindingAnnotation, CmpOp, Expr, ExprId, Label,
LabelId, Literal, LogicOp, MatchArm, Ordering, Pat, PatId, RecordFieldPat, RecordLitField,
Statement,
},
intern::Interned,
item_scope::BuiltinShadowMode,
path::{GenericArgs, Path},
type_ref::{Mutability, Rawness, TypeRef},
AdtId, BlockLoc, ModuleDefId, UnresolvedMacro,
};
pub struct LowerCtx<'a> {
pub db: &'a dyn DefDatabase,
hygiene: Hygiene,
file_id: Option<HirFileId>,
source_ast_id_map: Option<Arc<AstIdMap>>,
}
impl<'a> LowerCtx<'a> {
pub fn new(db: &'a dyn DefDatabase, file_id: HirFileId) -> Self {
LowerCtx {
db,
hygiene: Hygiene::new(db.upcast(), file_id),
file_id: Some(file_id),
source_ast_id_map: Some(db.ast_id_map(file_id)),
}
}
pub fn with_hygiene(db: &'a dyn DefDatabase, hygiene: &Hygiene) -> Self {
LowerCtx { db, hygiene: hygiene.clone(), file_id: None, source_ast_id_map: None }
}
pub(crate) fn hygiene(&self) -> &Hygiene {
&self.hygiene
}
pub(crate) fn file_id(&self) -> HirFileId {
self.file_id.unwrap()
}
pub(crate) fn lower_path(&self, ast: ast::Path) -> Option<Path> {
Path::from_src(ast, self)
}
pub(crate) fn ast_id<N: AstNode>(&self, item: &N) -> Option<FileAstId<N>> {
self.source_ast_id_map.as_ref().map(|ast_id_map| ast_id_map.ast_id(item))
}
}
pub(super) fn lower(
db: &dyn DefDatabase,
expander: Expander,
params: Option<ast::ParamList>,
body: Option<ast::Expr>,
) -> (Body, BodySourceMap) {
ExprCollector {
db,
source_map: BodySourceMap::default(),
body: Body {
exprs: Arena::default(),
pats: Arena::default(),
labels: Arena::default(),
params: Vec::new(),
body_expr: dummy_expr_id(),
block_scopes: Vec::new(),
_c: Count::new(),
},
expander,
statements_in_scope: Vec::new(),
}
.collect(params, body)
}
struct ExprCollector<'a> {
db: &'a dyn DefDatabase,
expander: Expander,
body: Body,
source_map: BodySourceMap,
statements_in_scope: Vec<Statement>,
}
impl ExprCollector<'_> {
fn collect(
mut self,
param_list: Option<ast::ParamList>,
body: Option<ast::Expr>,
) -> (Body, BodySourceMap) {
if let Some(param_list) = param_list {
if let Some(self_param) = param_list.self_param() {
let ptr = AstPtr::new(&self_param);
let param_pat = self.alloc_pat(
Pat::Bind {
name: name![self],
mode: BindingAnnotation::new(
self_param.mut_token().is_some() && self_param.amp_token().is_none(),
false,
),
subpat: None,
},
Either::Right(ptr),
);
self.body.params.push(param_pat);
}
for param in param_list.params() {
let pat = match param.pat() {
None => continue,
Some(pat) => pat,
};
let param_pat = self.collect_pat(pat);
self.body.params.push(param_pat);
}
};
self.body.body_expr = self.collect_expr_opt(body);
(self.body, self.source_map)
}
fn ctx(&self) -> LowerCtx<'_> {
LowerCtx::new(self.db, self.expander.current_file_id)
}
fn alloc_expr(&mut self, expr: Expr, ptr: AstPtr<ast::Expr>) -> ExprId {
let src = self.expander.to_source(ptr);
let id = self.make_expr(expr, Ok(src.clone()));
self.source_map.expr_map.insert(src, id);
id
}
// desugared exprs don't have ptr, that's wrong and should be fixed
// somehow.
fn alloc_expr_desugared(&mut self, expr: Expr) -> ExprId {
self.make_expr(expr, Err(SyntheticSyntax))
}
fn unit(&mut self) -> ExprId {
self.alloc_expr_desugared(Expr::Tuple { exprs: Vec::new() })
}
fn missing_expr(&mut self) -> ExprId {
self.alloc_expr_desugared(Expr::Missing)
}
fn make_expr(&mut self, expr: Expr, src: Result<ExprSource, SyntheticSyntax>) -> ExprId {
let id = self.body.exprs.alloc(expr);
self.source_map.expr_map_back.insert(id, src);
id
}
fn alloc_pat(&mut self, pat: Pat, ptr: PatPtr) -> PatId {
let src = self.expander.to_source(ptr);
let id = self.make_pat(pat, Ok(src.clone()));
self.source_map.pat_map.insert(src, id);
id
}
fn missing_pat(&mut self) -> PatId {
self.make_pat(Pat::Missing, Err(SyntheticSyntax))
}
fn make_pat(&mut self, pat: Pat, src: Result<PatSource, SyntheticSyntax>) -> PatId {
let id = self.body.pats.alloc(pat);
self.source_map.pat_map_back.insert(id, src);
id
}
fn alloc_label(&mut self, label: Label, ptr: AstPtr<ast::Label>) -> LabelId {
let src = self.expander.to_source(ptr);
let id = self.make_label(label, src.clone());
self.source_map.label_map.insert(src, id);
id
}
fn make_label(&mut self, label: Label, src: LabelSource) -> LabelId {
let id = self.body.labels.alloc(label);
self.source_map.label_map_back.insert(id, src);
id
}
fn collect_expr(&mut self, expr: ast::Expr) -> ExprId {
self.maybe_collect_expr(expr).unwrap_or_else(|| self.missing_expr())
}
/// Returns `None` if and only if the expression is `#[cfg]`d out.
fn maybe_collect_expr(&mut self, expr: ast::Expr) -> Option<ExprId> {
let syntax_ptr = AstPtr::new(&expr);
self.check_cfg(&expr)?;
Some(match expr {
ast::Expr::IfExpr(e) => {
let then_branch = self.collect_block_opt(e.then_branch());
let else_branch = e.else_branch().map(|b| match b {
ast::ElseBranch::Block(it) => self.collect_block(it),
ast::ElseBranch::IfExpr(elif) => {
let expr: ast::Expr = ast::Expr::cast(elif.syntax().clone()).unwrap();
self.collect_expr(expr)
}
});
let condition = match e.condition() {
None => self.missing_expr(),
Some(condition) => match condition.pat() {
None => self.collect_expr_opt(condition.expr()),
// if let -- desugar to match
Some(pat) => {
let pat = self.collect_pat(pat);
let match_expr = self.collect_expr_opt(condition.expr());
let placeholder_pat = self.missing_pat();
let arms = vec![
MatchArm { pat, expr: then_branch, guard: None },
MatchArm {
pat: placeholder_pat,
expr: else_branch.unwrap_or_else(|| self.unit()),
guard: None,
},
];
return Some(
self.alloc_expr(Expr::Match { expr: match_expr, arms }, syntax_ptr),
);
}
},
};
self.alloc_expr(Expr::If { condition, then_branch, else_branch }, syntax_ptr)
}
ast::Expr::EffectExpr(e) => match e.effect() {
ast::Effect::Try(_) => {
let body = self.collect_block_opt(e.block_expr());
self.alloc_expr(Expr::TryBlock { body }, syntax_ptr)
}
ast::Effect::Unsafe(_) => {
let body = self.collect_block_opt(e.block_expr());
self.alloc_expr(Expr::Unsafe { body }, syntax_ptr)
}
// FIXME: we need to record these effects somewhere...
ast::Effect::Label(label) => {
let label = self.collect_label(label);
match e.block_expr() {
Some(block) => {
let res = self.collect_block(block);
match &mut self.body.exprs[res] {
Expr::Block { label: block_label, .. } => {
*block_label = Some(label);
}
_ => unreachable!(),
}
res
}
None => self.missing_expr(),
}
}
// FIXME: we need to record these effects somewhere...
ast::Effect::Async(_) => {
let body = self.collect_block_opt(e.block_expr());
self.alloc_expr(Expr::Async { body }, syntax_ptr)
}
ast::Effect::Const(_) => {
let body = self.collect_block_opt(e.block_expr());
self.alloc_expr(Expr::Const { body }, syntax_ptr)
}
},
ast::Expr::BlockExpr(e) => self.collect_block(e),
ast::Expr::LoopExpr(e) => {
let label = e.label().map(|label| self.collect_label(label));
let body = self.collect_block_opt(e.loop_body());
self.alloc_expr(Expr::Loop { body, label }, syntax_ptr)
}
ast::Expr::WhileExpr(e) => {
let label = e.label().map(|label| self.collect_label(label));
let body = self.collect_block_opt(e.loop_body());
let condition = match e.condition() {
None => self.missing_expr(),
Some(condition) => match condition.pat() {
None => self.collect_expr_opt(condition.expr()),
// if let -- desugar to match
Some(pat) => {
cov_mark::hit!(infer_resolve_while_let);
let pat = self.collect_pat(pat);
let match_expr = self.collect_expr_opt(condition.expr());
let placeholder_pat = self.missing_pat();
let break_ =
self.alloc_expr_desugared(Expr::Break { expr: None, label: None });
let arms = vec![
MatchArm { pat, expr: body, guard: None },
MatchArm { pat: placeholder_pat, expr: break_, guard: None },
];
let match_expr =
self.alloc_expr_desugared(Expr::Match { expr: match_expr, arms });
return Some(
self.alloc_expr(Expr::Loop { body: match_expr, label }, syntax_ptr),
);
}
},
};
self.alloc_expr(Expr::While { condition, body, label }, syntax_ptr)
}
ast::Expr::ForExpr(e) => {
let label = e.label().map(|label| self.collect_label(label));
let iterable = self.collect_expr_opt(e.iterable());
let pat = self.collect_pat_opt(e.pat());
let body = self.collect_block_opt(e.loop_body());
self.alloc_expr(Expr::For { iterable, pat, body, label }, syntax_ptr)
}
ast::Expr::CallExpr(e) => {
let callee = self.collect_expr_opt(e.expr());
let args = if let Some(arg_list) = e.arg_list() {
arg_list.args().filter_map(|e| self.maybe_collect_expr(e)).collect()
} else {
Vec::new()
};
self.alloc_expr(Expr::Call { callee, args }, syntax_ptr)
}
ast::Expr::MethodCallExpr(e) => {
let receiver = self.collect_expr_opt(e.receiver());
let args = if let Some(arg_list) = e.arg_list() {
arg_list.args().filter_map(|e| self.maybe_collect_expr(e)).collect()
} else {
Vec::new()
};
let method_name = e.name_ref().map(|nr| nr.as_name()).unwrap_or_else(Name::missing);
let generic_args = e
.generic_arg_list()
.and_then(|it| GenericArgs::from_ast(&self.ctx(), it))
.map(Box::new);
self.alloc_expr(
Expr::MethodCall { receiver, method_name, args, generic_args },
syntax_ptr,
)
}
ast::Expr::MatchExpr(e) => {
let expr = self.collect_expr_opt(e.expr());
let arms = if let Some(match_arm_list) = e.match_arm_list() {
match_arm_list
.arms()
.filter_map(|arm| {
self.check_cfg(&arm).map(|()| MatchArm {
pat: self.collect_pat_opt(arm.pat()),
expr: self.collect_expr_opt(arm.expr()),
guard: arm
.guard()
.and_then(|guard| guard.expr())
.map(|e| self.collect_expr(e)),
})
})
.collect()
} else {
Vec::new()
};
self.alloc_expr(Expr::Match { expr, arms }, syntax_ptr)
}
ast::Expr::PathExpr(e) => {
let path = e
.path()
.and_then(|path| self.expander.parse_path(self.db, path))
.map(Expr::Path)
.unwrap_or(Expr::Missing);
self.alloc_expr(path, syntax_ptr)
}
ast::Expr::ContinueExpr(e) => self.alloc_expr(
Expr::Continue { label: e.lifetime().map(|l| Name::new_lifetime(&l)) },
syntax_ptr,
),
ast::Expr::BreakExpr(e) => {
let expr = e.expr().map(|e| self.collect_expr(e));
self.alloc_expr(
Expr::Break { expr, label: e.lifetime().map(|l| Name::new_lifetime(&l)) },
syntax_ptr,
)
}
ast::Expr::ParenExpr(e) => {
let inner = self.collect_expr_opt(e.expr());
// make the paren expr point to the inner expression as well
let src = self.expander.to_source(syntax_ptr);
self.source_map.expr_map.insert(src, inner);
inner
}
ast::Expr::ReturnExpr(e) => {
let expr = e.expr().map(|e| self.collect_expr(e));
self.alloc_expr(Expr::Return { expr }, syntax_ptr)
}
ast::Expr::YieldExpr(e) => {
let expr = e.expr().map(|e| self.collect_expr(e));
self.alloc_expr(Expr::Yield { expr }, syntax_ptr)
}
ast::Expr::RecordExpr(e) => {
let path =
e.path().and_then(|path| self.expander.parse_path(self.db, path)).map(Box::new);
let record_lit = if let Some(nfl) = e.record_expr_field_list() {
let fields = nfl
.fields()
.filter_map(|field| {
self.check_cfg(&field)?;
let name = field.field_name()?.as_name();
let expr = match field.expr() {
Some(e) => self.collect_expr(e),
None => self.missing_expr(),
};
let src = self.expander.to_source(AstPtr::new(&field));
self.source_map.field_map.insert(src.clone(), expr);
self.source_map.field_map_back.insert(expr, src);
Some(RecordLitField { name, expr })
})
.collect();
let spread = nfl.spread().map(|s| self.collect_expr(s));
Expr::RecordLit { path, fields, spread }
} else {
Expr::RecordLit { path, fields: Vec::new(), spread: None }
};
self.alloc_expr(record_lit, syntax_ptr)
}
ast::Expr::FieldExpr(e) => {
let expr = self.collect_expr_opt(e.expr());
let name = match e.field_access() {
Some(kind) => kind.as_name(),
_ => Name::missing(),
};
self.alloc_expr(Expr::Field { expr, name }, syntax_ptr)
}
ast::Expr::AwaitExpr(e) => {
let expr = self.collect_expr_opt(e.expr());
self.alloc_expr(Expr::Await { expr }, syntax_ptr)
}
ast::Expr::TryExpr(e) => {
let expr = self.collect_expr_opt(e.expr());
self.alloc_expr(Expr::Try { expr }, syntax_ptr)
}
ast::Expr::CastExpr(e) => {
let expr = self.collect_expr_opt(e.expr());
let type_ref = Interned::new(TypeRef::from_ast_opt(&self.ctx(), e.ty()));
self.alloc_expr(Expr::Cast { expr, type_ref }, syntax_ptr)
}
ast::Expr::RefExpr(e) => {
let expr = self.collect_expr_opt(e.expr());
let raw_tok = e.raw_token().is_some();
let mutability = if raw_tok {
if e.mut_token().is_some() {
Mutability::Mut
} else if e.const_token().is_some() {
Mutability::Shared
} else {
unreachable!("parser only remaps to raw_token() if matching mutability token follows")
}
} else {
Mutability::from_mutable(e.mut_token().is_some())
};
let rawness = Rawness::from_raw(raw_tok);
self.alloc_expr(Expr::Ref { expr, rawness, mutability }, syntax_ptr)
}
ast::Expr::PrefixExpr(e) => {
let expr = self.collect_expr_opt(e.expr());
if let Some(op) = e.op_kind() {
self.alloc_expr(Expr::UnaryOp { expr, op }, syntax_ptr)
} else {
self.alloc_expr(Expr::Missing, syntax_ptr)
}
}
ast::Expr::ClosureExpr(e) => {
let mut args = Vec::new();
let mut arg_types = Vec::new();
if let Some(pl) = e.param_list() {
for param in pl.params() {
let pat = self.collect_pat_opt(param.pat());
let type_ref =
param.ty().map(|it| Interned::new(TypeRef::from_ast(&self.ctx(), it)));
args.push(pat);
arg_types.push(type_ref);
}
}
let ret_type = e
.ret_type()
.and_then(|r| r.ty())
.map(|it| Interned::new(TypeRef::from_ast(&self.ctx(), it)));
let body = self.collect_expr_opt(e.body());
self.alloc_expr(Expr::Lambda { args, arg_types, ret_type, body }, syntax_ptr)
}
ast::Expr::BinExpr(e) => {
let lhs = self.collect_expr_opt(e.lhs());
let rhs = self.collect_expr_opt(e.rhs());
let op = e.op_kind().map(BinaryOp::from);
self.alloc_expr(Expr::BinaryOp { lhs, rhs, op }, syntax_ptr)
}
ast::Expr::TupleExpr(e) => {
let exprs = e.fields().map(|expr| self.collect_expr(expr)).collect();
self.alloc_expr(Expr::Tuple { exprs }, syntax_ptr)
}
ast::Expr::BoxExpr(e) => {
let expr = self.collect_expr_opt(e.expr());
self.alloc_expr(Expr::Box { expr }, syntax_ptr)
}
ast::Expr::ArrayExpr(e) => {
let kind = e.kind();
match kind {
ArrayExprKind::ElementList(e) => {
let exprs = e.map(|expr| self.collect_expr(expr)).collect();
self.alloc_expr(Expr::Array(Array::ElementList(exprs)), syntax_ptr)
}
ArrayExprKind::Repeat { initializer, repeat } => {
let initializer = self.collect_expr_opt(initializer);
let repeat = self.collect_expr_opt(repeat);
self.alloc_expr(
Expr::Array(Array::Repeat { initializer, repeat }),
syntax_ptr,
)
}
}
}
ast::Expr::Literal(e) => self.alloc_expr(Expr::Literal(e.kind().into()), syntax_ptr),
ast::Expr::IndexExpr(e) => {
let base = self.collect_expr_opt(e.base());
let index = self.collect_expr_opt(e.index());
self.alloc_expr(Expr::Index { base, index }, syntax_ptr)
}
ast::Expr::RangeExpr(e) => {
let lhs = e.start().map(|lhs| self.collect_expr(lhs));
let rhs = e.end().map(|rhs| self.collect_expr(rhs));
match e.op_kind() {
Some(range_type) => {
self.alloc_expr(Expr::Range { lhs, rhs, range_type }, syntax_ptr)
}
None => self.alloc_expr(Expr::Missing, syntax_ptr),
}
}
ast::Expr::MacroCall(e) => {
let macro_ptr = AstPtr::new(&e);
let mut ids = vec![];
self.collect_macro_call(e, macro_ptr, true, |this, expansion| {
ids.push(match expansion {
Some(it) => this.collect_expr(it),
None => this.alloc_expr(Expr::Missing, syntax_ptr.clone()),
})
});
ids[0]
}
ast::Expr::MacroStmts(e) => {
e.statements().for_each(|s| self.collect_stmt(s));
let tail = e
.expr()
.map(|e| self.collect_expr(e))
.unwrap_or_else(|| self.alloc_expr(Expr::Missing, syntax_ptr.clone()));
self.alloc_expr(Expr::MacroStmts { tail }, syntax_ptr)
}
})
}
fn collect_macro_call<F: FnMut(&mut Self, Option<T>), T: ast::AstNode>(
&mut self,
e: ast::MacroCall,
syntax_ptr: AstPtr<ast::MacroCall>,
is_error_recoverable: bool,
mut collector: F,
) {
// File containing the macro call. Expansion errors will be attached here.
let outer_file = self.expander.current_file_id;
let macro_call = self.expander.to_source(AstPtr::new(&e));
let res = self.expander.enter_expand(self.db, e);
let res = match res {
Ok(res) => res,
Err(UnresolvedMacro { path }) => {
self.source_map.diagnostics.push(BodyDiagnostic::UnresolvedMacroCall {
node: InFile::new(outer_file, syntax_ptr),
path,
});
collector(self, None);
return;
}
};
match &res.err {
Some(ExpandError::UnresolvedProcMacro) => {
self.source_map.diagnostics.push(BodyDiagnostic::UnresolvedProcMacro {
node: InFile::new(outer_file, syntax_ptr),
});
}
Some(err) => {
self.source_map.diagnostics.push(BodyDiagnostic::MacroError {
node: InFile::new(outer_file, syntax_ptr),
message: err.to_string(),
});
}
None => {}
}
match res.value {
Some((mark, expansion)) => {
// FIXME: Statements are too complicated to recover from error for now.
// It is because we don't have any hygiene for local variable expansion right now.
if !is_error_recoverable && res.err.is_some() {
self.expander.exit(self.db, mark);
collector(self, None);
} else {
self.source_map.expansions.insert(macro_call, self.expander.current_file_id);
let id = collector(self, Some(expansion));
self.expander.exit(self.db, mark);
id
}
}
None => collector(self, None),
}
}
fn collect_expr_opt(&mut self, expr: Option<ast::Expr>) -> ExprId {
if let Some(expr) = expr {
self.collect_expr(expr)
} else {
self.missing_expr()
}
}
fn collect_stmt(&mut self, s: ast::Stmt) {
match s {
ast::Stmt::LetStmt(stmt) => {
if self.check_cfg(&stmt).is_none() {
return;
}
let pat = self.collect_pat_opt(stmt.pat());
let type_ref =
stmt.ty().map(|it| Interned::new(TypeRef::from_ast(&self.ctx(), it)));
let initializer = stmt.initializer().map(|e| self.collect_expr(e));
self.statements_in_scope.push(Statement::Let { pat, type_ref, initializer });
}
ast::Stmt::ExprStmt(stmt) => {
if self.check_cfg(&stmt).is_none() {
return;
}
let has_semi = stmt.semicolon_token().is_some();
// Note that macro could be expended to multiple statements
if let Some(ast::Expr::MacroCall(m)) = stmt.expr() {
let macro_ptr = AstPtr::new(&m);
let syntax_ptr = AstPtr::new(&stmt.expr().unwrap());
self.collect_macro_call(
m,
macro_ptr,
false,
|this, expansion| match expansion {
Some(expansion) => {
let statements: ast::MacroStmts = expansion;
statements.statements().for_each(|stmt| this.collect_stmt(stmt));
if let Some(expr) = statements.expr() {
let expr = this.collect_expr(expr);
this.statements_in_scope
.push(Statement::Expr { expr, has_semi });
}
}
None => {
let expr = this.alloc_expr(Expr::Missing, syntax_ptr.clone());
this.statements_in_scope.push(Statement::Expr { expr, has_semi });
}
},
);
} else {
let expr = self.collect_expr_opt(stmt.expr());
self.statements_in_scope.push(Statement::Expr { expr, has_semi });
}
}
ast::Stmt::Item(item) => {
self.check_cfg(&item);
}
}
}
fn collect_block(&mut self, block: ast::BlockExpr) -> ExprId {
let ast_id = self.expander.ast_id(&block);
let block_loc =
BlockLoc { ast_id, module: self.expander.def_map.module_id(self.expander.module) };
let block_id = self.db.intern_block(block_loc);
let (module, def_map) = match self.db.block_def_map(block_id) {
Some(def_map) => {
self.body.block_scopes.push(block_id);
(def_map.root(), def_map)
}
None => (self.expander.module, self.expander.def_map.clone()),
};
let prev_def_map = mem::replace(&mut self.expander.def_map, def_map);
let prev_local_module = mem::replace(&mut self.expander.module, module);
let prev_statements = std::mem::take(&mut self.statements_in_scope);
block.statements().for_each(|s| self.collect_stmt(s));
block.tail_expr().and_then(|e| {
let expr = self.maybe_collect_expr(e)?;
self.statements_in_scope.push(Statement::Expr { expr, has_semi: false });
Some(())
});
let mut tail = None;
if let Some(Statement::Expr { expr, has_semi: false }) = self.statements_in_scope.last() {
tail = Some(*expr);
self.statements_in_scope.pop();
}
let tail = tail;
let statements = std::mem::replace(&mut self.statements_in_scope, prev_statements);
let syntax_node_ptr = AstPtr::new(&block.into());
let expr_id = self.alloc_expr(
Expr::Block { id: block_id, statements, tail, label: None },
syntax_node_ptr,
);
self.expander.def_map = prev_def_map;
self.expander.module = prev_local_module;
expr_id
}
fn collect_block_opt(&mut self, expr: Option<ast::BlockExpr>) -> ExprId {
if let Some(block) = expr {
self.collect_block(block)
} else {
self.missing_expr()
}
}
fn collect_label(&mut self, ast_label: ast::Label) -> LabelId {
let label = Label {
name: ast_label.lifetime().as_ref().map_or_else(Name::missing, Name::new_lifetime),
};
self.alloc_label(label, AstPtr::new(&ast_label))
}
fn collect_pat(&mut self, pat: ast::Pat) -> PatId {
let pattern = match &pat {
ast::Pat::IdentPat(bp) => {
let name = bp.name().map(|nr| nr.as_name()).unwrap_or_else(Name::missing);
let annotation =
BindingAnnotation::new(bp.mut_token().is_some(), bp.ref_token().is_some());
let subpat = bp.pat().map(|subpat| self.collect_pat(subpat));
if annotation == BindingAnnotation::Unannotated && subpat.is_none() {
// This could also be a single-segment path pattern. To
// decide that, we need to try resolving the name.
let (resolved, _) = self.expander.def_map.resolve_path(
self.db,
self.expander.module,
&name.clone().into(),
BuiltinShadowMode::Other,
);
match resolved.take_values() {
Some(ModuleDefId::ConstId(_)) => Pat::Path(name.into()),
Some(ModuleDefId::EnumVariantId(_)) => {
// this is only really valid for unit variants, but
// shadowing other enum variants with a pattern is
// an error anyway
Pat::Path(name.into())
}
Some(ModuleDefId::AdtId(AdtId::StructId(s)))
if self.db.struct_data(s).variant_data.kind() != StructKind::Record =>
{
// Funnily enough, record structs *can* be shadowed
// by pattern bindings (but unit or tuple structs
// can't).
Pat::Path(name.into())
}
// shadowing statics is an error as well, so we just ignore that case here
_ => Pat::Bind { name, mode: annotation, subpat },
}
} else {
Pat::Bind { name, mode: annotation, subpat }
}
}
ast::Pat::TupleStructPat(p) => {
let path =
p.path().and_then(|path| self.expander.parse_path(self.db, path)).map(Box::new);
let (args, ellipsis) = self.collect_tuple_pat(p.fields());
Pat::TupleStruct { path, args, ellipsis }
}
ast::Pat::RefPat(p) => {
let pat = self.collect_pat_opt(p.pat());
let mutability = Mutability::from_mutable(p.mut_token().is_some());
Pat::Ref { pat, mutability }
}
ast::Pat::PathPat(p) => {
let path =
p.path().and_then(|path| self.expander.parse_path(self.db, path)).map(Box::new);
path.map(Pat::Path).unwrap_or(Pat::Missing)
}
ast::Pat::OrPat(p) => {
let pats = p.pats().map(|p| self.collect_pat(p)).collect();
Pat::Or(pats)
}
ast::Pat::ParenPat(p) => return self.collect_pat_opt(p.pat()),
ast::Pat::TuplePat(p) => {
let (args, ellipsis) = self.collect_tuple_pat(p.fields());
Pat::Tuple { args, ellipsis }
}
ast::Pat::WildcardPat(_) => Pat::Wild,
ast::Pat::RecordPat(p) => {
let path =
p.path().and_then(|path| self.expander.parse_path(self.db, path)).map(Box::new);
let args: Vec<_> = p
.record_pat_field_list()
.expect("every struct should have a field list")
.fields()
.filter_map(|f| {
let ast_pat = f.pat()?;
let pat = self.collect_pat(ast_pat);
let name = f.field_name()?.as_name();
Some(RecordFieldPat { name, pat })
})
.collect();
let ellipsis = p
.record_pat_field_list()
.expect("every struct should have a field list")
.dotdot_token()
.is_some();
Pat::Record { path, args, ellipsis }
}
ast::Pat::SlicePat(p) => {
let SlicePatComponents { prefix, slice, suffix } = p.components();
// FIXME properly handle `RestPat`
Pat::Slice {
prefix: prefix.into_iter().map(|p| self.collect_pat(p)).collect(),
slice: slice.map(|p| self.collect_pat(p)),
suffix: suffix.into_iter().map(|p| self.collect_pat(p)).collect(),
}
}
ast::Pat::LiteralPat(lit) => {
if let Some(ast_lit) = lit.literal() {
let expr = Expr::Literal(ast_lit.kind().into());
let expr_ptr = AstPtr::new(&ast::Expr::Literal(ast_lit));
let expr_id = self.alloc_expr(expr, expr_ptr);
Pat::Lit(expr_id)
} else {
Pat::Missing
}
}
ast::Pat::RestPat(_) => {
// `RestPat` requires special handling and should not be mapped
// to a Pat. Here we are using `Pat::Missing` as a fallback for
// when `RestPat` is mapped to `Pat`, which can easily happen
// when the source code being analyzed has a malformed pattern
// which includes `..` in a place where it isn't valid.
Pat::Missing
}
ast::Pat::BoxPat(boxpat) => {
let inner = self.collect_pat_opt(boxpat.pat());
Pat::Box { inner }
}
ast::Pat::ConstBlockPat(const_block_pat) => {
if let Some(expr) = const_block_pat.block_expr() {
let expr_id = self.collect_block(expr);
Pat::ConstBlock(expr_id)
} else {
Pat::Missing
}
}
ast::Pat::MacroPat(mac) => match mac.macro_call() {
Some(call) => {
let macro_ptr = AstPtr::new(&call);
let mut pat = None;
self.collect_macro_call(call, macro_ptr, true, |this, expanded_pat| {
pat = Some(this.collect_pat_opt(expanded_pat));
});
match pat {
Some(pat) => return pat,
None => Pat::Missing,
}
}
None => Pat::Missing,
},
// FIXME: implement
ast::Pat::RangePat(_) => Pat::Missing,
};
let ptr = AstPtr::new(&pat);
self.alloc_pat(pattern, Either::Left(ptr))
}
fn collect_pat_opt(&mut self, pat: Option<ast::Pat>) -> PatId {
if let Some(pat) = pat {
self.collect_pat(pat)
} else {
self.missing_pat()
}
}
fn collect_tuple_pat(&mut self, args: AstChildren<ast::Pat>) -> (Vec<PatId>, Option<usize>) {
// Find the location of the `..`, if there is one. Note that we do not
// consider the possibility of there being multiple `..` here.
let ellipsis = args.clone().position(|p| matches!(p, ast::Pat::RestPat(_)));
// We want to skip the `..` pattern here, since we account for it above.
let args = args
.filter(|p| !matches!(p, ast::Pat::RestPat(_)))
.map(|p| self.collect_pat(p))
.collect();
(args, ellipsis)
}
/// Returns `None` (and emits diagnostics) when `owner` if `#[cfg]`d out, and `Some(())` when
/// not.
fn check_cfg(&mut self, owner: &dyn ast::AttrsOwner) -> Option<()> {
match self.expander.parse_attrs(self.db, owner).cfg() {
Some(cfg) => {
if self.expander.cfg_options().check(&cfg) != Some(false) {
return Some(());
}
self.source_map.diagnostics.push(BodyDiagnostic::InactiveCode {
node: InFile::new(
self.expander.current_file_id,
SyntaxNodePtr::new(owner.syntax()),
),
cfg,
opts: self.expander.cfg_options().clone(),
});
None
}
None => Some(()),
}
}
}
impl From<ast::BinOp> for BinaryOp {
fn from(ast_op: ast::BinOp) -> Self {
match ast_op {
ast::BinOp::BooleanOr => BinaryOp::LogicOp(LogicOp::Or),
ast::BinOp::BooleanAnd => BinaryOp::LogicOp(LogicOp::And),
ast::BinOp::EqualityTest => BinaryOp::CmpOp(CmpOp::Eq { negated: false }),
ast::BinOp::NegatedEqualityTest => BinaryOp::CmpOp(CmpOp::Eq { negated: true }),
ast::BinOp::LesserEqualTest => {
BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Less, strict: false })
}
ast::BinOp::GreaterEqualTest => {
BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Greater, strict: false })
}
ast::BinOp::LesserTest => {
BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Less, strict: true })
}
ast::BinOp::GreaterTest => {
BinaryOp::CmpOp(CmpOp::Ord { ordering: Ordering::Greater, strict: true })
}
ast::BinOp::Addition => BinaryOp::ArithOp(ArithOp::Add),
ast::BinOp::Multiplication => BinaryOp::ArithOp(ArithOp::Mul),
ast::BinOp::Subtraction => BinaryOp::ArithOp(ArithOp::Sub),
ast::BinOp::Division => BinaryOp::ArithOp(ArithOp::Div),
ast::BinOp::Remainder => BinaryOp::ArithOp(ArithOp::Rem),
ast::BinOp::LeftShift => BinaryOp::ArithOp(ArithOp::Shl),
ast::BinOp::RightShift => BinaryOp::ArithOp(ArithOp::Shr),
ast::BinOp::BitwiseXor => BinaryOp::ArithOp(ArithOp::BitXor),
ast::BinOp::BitwiseOr => BinaryOp::ArithOp(ArithOp::BitOr),
ast::BinOp::BitwiseAnd => BinaryOp::ArithOp(ArithOp::BitAnd),
ast::BinOp::Assignment => BinaryOp::Assignment { op: None },
ast::BinOp::AddAssign => BinaryOp::Assignment { op: Some(ArithOp::Add) },
ast::BinOp::DivAssign => BinaryOp::Assignment { op: Some(ArithOp::Div) },
ast::BinOp::MulAssign => BinaryOp::Assignment { op: Some(ArithOp::Mul) },
ast::BinOp::RemAssign => BinaryOp::Assignment { op: Some(ArithOp::Rem) },
ast::BinOp::ShlAssign => BinaryOp::Assignment { op: Some(ArithOp::Shl) },
ast::BinOp::ShrAssign => BinaryOp::Assignment { op: Some(ArithOp::Shr) },
ast::BinOp::SubAssign => BinaryOp::Assignment { op: Some(ArithOp::Sub) },
ast::BinOp::BitOrAssign => BinaryOp::Assignment { op: Some(ArithOp::BitOr) },
ast::BinOp::BitAndAssign => BinaryOp::Assignment { op: Some(ArithOp::BitAnd) },
ast::BinOp::BitXorAssign => BinaryOp::Assignment { op: Some(ArithOp::BitXor) },
}
}
}
impl From<ast::LiteralKind> for Literal {
fn from(ast_lit_kind: ast::LiteralKind) -> Self {
match ast_lit_kind {
// FIXME: these should have actual values filled in, but unsure on perf impact
LiteralKind::IntNumber(lit) => {
if let builtin @ Some(_) = lit.suffix().and_then(BuiltinFloat::from_suffix) {
Literal::Float(Default::default(), builtin)
} else if let builtin @ Some(_) =
lit.suffix().and_then(|it| BuiltinInt::from_suffix(it))
{
Literal::Int(lit.value().unwrap_or(0) as i128, builtin)
} else {
let builtin = lit.suffix().and_then(|it| BuiltinUint::from_suffix(it));
Literal::Uint(lit.value().unwrap_or(0), builtin)
}
}
LiteralKind::FloatNumber(lit) => {
let ty = lit.suffix().and_then(|it| BuiltinFloat::from_suffix(it));
Literal::Float(Default::default(), ty)
}
LiteralKind::ByteString(bs) => {
let text = bs.value().map(Vec::from).unwrap_or_else(Default::default);
Literal::ByteString(text)
}
LiteralKind::String(_) => Literal::String(Default::default()),
LiteralKind::Byte => Literal::Uint(Default::default(), Some(BuiltinUint::U8)),
LiteralKind::Bool(val) => Literal::Bool(val),
LiteralKind::Char => Literal::Char(Default::default()),
}
}
}