From 33d637f2ddb5e5eab6d5dfaf75042dfc1a58d241 Mon Sep 17 00:00:00 2001 From: Florian Diebold Date: Fri, 17 Jan 2020 16:59:02 +0100 Subject: Fix inference for shift operators Fixes #2602. --- crates/ra_hir_ty/src/infer/expr.rs | 4 ++-- crates/ra_hir_ty/src/op.rs | 15 ++++++++++++--- crates/ra_hir_ty/src/tests/simple.rs | 21 +++++++++++++++++++++ 3 files changed, 35 insertions(+), 5 deletions(-) (limited to 'crates/ra_hir_ty') diff --git a/crates/ra_hir_ty/src/infer/expr.rs b/crates/ra_hir_ty/src/infer/expr.rs index d6a17e469..31259a01d 100644 --- a/crates/ra_hir_ty/src/infer/expr.rs +++ b/crates/ra_hir_ty/src/infer/expr.rs @@ -386,11 +386,11 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> { let lhs_ty = self.infer_expr(*lhs, &lhs_expectation); // FIXME: find implementation of trait corresponding to operation // symbol and resolve associated `Output` type - let rhs_expectation = op::binary_op_rhs_expectation(*op, lhs_ty); + let rhs_expectation = op::binary_op_rhs_expectation(*op, lhs_ty.clone()); let rhs_ty = self.infer_expr(*rhs, &Expectation::has_type(rhs_expectation)); // FIXME: similar as above, return ty is often associated trait type - op::binary_op_return_ty(*op, rhs_ty) + op::binary_op_return_ty(*op, lhs_ty, rhs_ty) } _ => Ty::Unknown, }, diff --git a/crates/ra_hir_ty/src/op.rs b/crates/ra_hir_ty/src/op.rs index 09c47a76d..ae253ca04 100644 --- a/crates/ra_hir_ty/src/op.rs +++ b/crates/ra_hir_ty/src/op.rs @@ -1,13 +1,21 @@ -//! FIXME: write short doc here -use hir_def::expr::{BinaryOp, CmpOp}; +//! Helper functions for binary operator type inference. +use hir_def::expr::{ArithOp, BinaryOp, CmpOp}; use super::{InferTy, Ty, TypeCtor}; use crate::ApplicationTy; -pub(super) fn binary_op_return_ty(op: BinaryOp, rhs_ty: Ty) -> Ty { +pub(super) fn binary_op_return_ty(op: BinaryOp, lhs_ty: Ty, rhs_ty: Ty) -> Ty { match op { BinaryOp::LogicOp(_) | BinaryOp::CmpOp(_) => Ty::simple(TypeCtor::Bool), BinaryOp::Assignment { .. } => Ty::unit(), + BinaryOp::ArithOp(ArithOp::Shl) | BinaryOp::ArithOp(ArithOp::Shr) => match lhs_ty { + Ty::Apply(ApplicationTy { ctor, .. }) => match ctor { + TypeCtor::Int(..) | TypeCtor::Float(..) => lhs_ty, + _ => Ty::Unknown, + }, + Ty::Infer(InferTy::IntVar(..)) | Ty::Infer(InferTy::FloatVar(..)) => lhs_ty, + _ => Ty::Unknown, + }, BinaryOp::ArithOp(_) => match rhs_ty { Ty::Apply(ApplicationTy { ctor, .. }) => match ctor { TypeCtor::Int(..) | TypeCtor::Float(..) => rhs_ty, @@ -36,6 +44,7 @@ pub(super) fn binary_op_rhs_expectation(op: BinaryOp, lhs_ty: Ty) -> Ty { _ => Ty::Unknown, } } + BinaryOp::ArithOp(ArithOp::Shl) | BinaryOp::ArithOp(ArithOp::Shr) => Ty::Unknown, BinaryOp::CmpOp(CmpOp::Ord { .. }) | BinaryOp::Assignment { op: Some(_) } | BinaryOp::ArithOp(_) => match lhs_ty { diff --git a/crates/ra_hir_ty/src/tests/simple.rs b/crates/ra_hir_ty/src/tests/simple.rs index f7e042c12..b7204ec00 100644 --- a/crates/ra_hir_ty/src/tests/simple.rs +++ b/crates/ra_hir_ty/src/tests/simple.rs @@ -613,6 +613,27 @@ fn test() -> bool { ); } +#[test] +fn infer_shift_op() { + assert_snapshot!( + infer(r#" +fn test() { + 1u32 << 5u8; + 1u32 >> 5u8; +} +"#), + @r###" + [11; 48) '{ ...5u8; }': () + [17; 21) '1u32': u32 + [17; 28) '1u32 << 5u8': u32 + [25; 28) '5u8': u8 + [34; 38) '1u32': u32 + [34; 45) '1u32 >> 5u8': u32 + [42; 45) '5u8': u8 + "### + ); +} + #[test] fn infer_field_autoderef() { assert_snapshot!( -- cgit v1.2.3