rust/crates/ra_hir/src/expr.rs
2019-11-26 14:29:12 +03:00

147 lines
4.5 KiB
Rust

//! FIXME: write short doc here
use std::sync::Arc;
use hir_def::{path::known, resolver::HasResolver, AdtId};
use hir_expand::diagnostics::DiagnosticSink;
use ra_syntax::ast;
use ra_syntax::AstPtr;
use rustc_hash::FxHashSet;
use crate::{
db::HirDatabase,
diagnostics::{MissingFields, MissingOkInTailExpr},
ty::{ApplicationTy, InferenceResult, Ty, TypeCtor},
Adt, Function, Name, Path,
};
pub use hir_def::{
body::{
scope::{ExprScopes, ScopeEntry, ScopeId},
Body, BodySourceMap, ExprPtr, ExprSource, PatPtr, PatSource,
},
expr::{
ArithOp, Array, BinaryOp, BindingAnnotation, CmpOp, Expr, ExprId, Literal, LogicOp,
MatchArm, Ordering, Pat, PatId, RecordFieldPat, RecordLitField, Statement, UnaryOp,
},
};
pub(crate) struct ExprValidator<'a, 'b: 'a> {
func: Function,
infer: Arc<InferenceResult>,
sink: &'a mut DiagnosticSink<'b>,
}
impl<'a, 'b> ExprValidator<'a, 'b> {
pub(crate) fn new(
func: Function,
infer: Arc<InferenceResult>,
sink: &'a mut DiagnosticSink<'b>,
) -> ExprValidator<'a, 'b> {
ExprValidator { func, infer, sink }
}
pub(crate) fn validate_body(&mut self, db: &impl HirDatabase) {
let body = self.func.body(db);
for e in body.exprs.iter() {
if let (id, Expr::RecordLit { path, fields, spread }) = e {
self.validate_record_literal(id, path, fields, *spread, db);
}
}
let body_expr = &body[body.body_expr];
if let Expr::Block { statements: _, tail: Some(t) } = body_expr {
self.validate_results_in_tail_expr(body.body_expr, *t, db);
}
}
fn validate_record_literal(
&mut self,
id: ExprId,
_path: &Option<Path>,
fields: &[RecordLitField],
spread: Option<ExprId>,
db: &impl HirDatabase,
) {
if spread.is_some() {
return;
}
let struct_def = match self.infer[id].as_adt() {
Some((Adt::Struct(s), _)) => s,
_ => return,
};
let lit_fields: FxHashSet<_> = fields.iter().map(|f| &f.name).collect();
let missed_fields: Vec<Name> = struct_def
.fields(db)
.iter()
.filter_map(|f| {
let name = f.name(db);
if lit_fields.contains(&name) {
None
} else {
Some(name)
}
})
.collect();
if missed_fields.is_empty() {
return;
}
let source_map = self.func.body_source_map(db);
if let Some(source_ptr) = source_map.expr_syntax(id) {
if let Some(expr) = source_ptr.value.a() {
let root = source_ptr.file_syntax(db);
if let ast::Expr::RecordLit(record_lit) = expr.to_node(&root) {
if let Some(field_list) = record_lit.record_field_list() {
self.sink.push(MissingFields {
file: source_ptr.file_id,
field_list: AstPtr::new(&field_list),
missed_fields,
})
}
}
}
}
}
fn validate_results_in_tail_expr(
&mut self,
body_id: ExprId,
id: ExprId,
db: &impl HirDatabase,
) {
// the mismatch will be on the whole block currently
let mismatch = match self.infer.type_mismatch_for_expr(body_id) {
Some(m) => m,
None => return,
};
let std_result_path = known::std_result_result();
let resolver = self.func.id.resolver(db);
let std_result_enum = match resolver.resolve_known_enum(db, &std_result_path) {
Some(it) => it,
_ => return,
};
let std_result_ctor = TypeCtor::Adt(AdtId::EnumId(std_result_enum));
let params = match &mismatch.expected {
Ty::Apply(ApplicationTy { ctor, parameters }) if ctor == &std_result_ctor => parameters,
_ => return,
};
if params.len() == 2 && &params[0] == &mismatch.actual {
let source_map = self.func.body_source_map(db);
if let Some(source_ptr) = source_map.expr_syntax(id) {
if let Some(expr) = source_ptr.value.a() {
self.sink.push(MissingOkInTailExpr { file: source_ptr.file_id, expr });
}
}
}
}
}