From 20971602d538fd3a7936171708fba36349b6fe22 Mon Sep 17 00:00:00 2001 From: Shoyu Vanilla Date: Sun, 11 Aug 2024 22:48:37 +0900 Subject: [PATCH] feat: `min-exhaustive-patterns --- .../crates/hir-ty/src/diagnostics/expr.rs | 65 ++++++++++++++++--- .../diagnostics/match_check/pat_analysis.rs | 11 ++-- .../src/handlers/missing_match_arms.rs | 38 +++++++++++ .../src/handlers/non_exhaustive_let.rs | 32 +++++++++ 4 files changed, 131 insertions(+), 15 deletions(-) diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/expr.rs b/src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/expr.rs index 06c9b2e0e5b..6e5a7cce9c9 100644 --- a/src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/expr.rs +++ b/src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/expr.rs @@ -4,20 +4,25 @@ use std::fmt; +use chalk_solve::rust_ir::AdtKind; use either::Either; -use hir_def::lang_item::LangItem; -use hir_def::{resolver::HasResolver, AdtId, AssocItemId, DefWithBodyId, HasModule}; -use hir_def::{ItemContainerId, Lookup}; +use hir_def::{ + lang_item::LangItem, + resolver::{HasResolver, ValueNs}, + AdtId, AssocItemId, DefWithBodyId, HasModule, ItemContainerId, Lookup, +}; use intern::sym; use itertools::Itertools; use rustc_hash::FxHashSet; use rustc_pattern_analysis::constructor::Constructor; -use syntax::{ast, AstNode}; +use syntax::{ + ast::{self, UnaryOp}, + AstNode, +}; use tracing::debug; use triomphe::Arc; use typed_arena::Arena; -use crate::Interner; use crate::{ db::HirDatabase, diagnostics::match_check::{ @@ -25,7 +30,7 @@ pat_analysis::{self, DeconstructedPat, MatchCheckCtx, WitnessPat}, }, display::HirDisplay, - InferenceResult, Ty, TyExt, + Adjust, InferenceResult, Interner, Ty, TyExt, TyKind, }; pub(crate) use hir_def::{ @@ -236,7 +241,12 @@ fn validate_match( return; } - let report = match cx.compute_match_usefulness(m_arms.as_slice(), scrut_ty.clone()) { + let known_valid_scrutinee = Some(self.is_known_valid_scrutinee(scrutinee_expr, db)); + let report = match cx.compute_match_usefulness( + m_arms.as_slice(), + scrut_ty.clone(), + known_valid_scrutinee, + ) { Ok(report) => report, Err(()) => return, }; @@ -253,6 +263,45 @@ fn validate_match( } } + // [rustc's `is_known_valid_scrutinee`](https://github.com/rust-lang/rust/blob/c9bd03cb724e13cca96ad320733046cbdb16fbbe/compiler/rustc_mir_build/src/thir/pattern/check_match.rs#L288) + // + // While the above function in rustc uses thir exprs, r-a doesn't have them. + // So, the logic here is getting same result as "hir lowering + match with lowered thir" + // with "hir only" + fn is_known_valid_scrutinee(&self, scrutinee_expr: ExprId, db: &dyn HirDatabase) -> bool { + if self + .infer + .expr_adjustments + .get(&scrutinee_expr) + .is_some_and(|adjusts| adjusts.iter().any(|a| matches!(a.kind, Adjust::Deref(..)))) + { + return false; + } + + match &self.body[scrutinee_expr] { + Expr::UnaryOp { op: UnaryOp::Deref, .. } => false, + Expr::Path(path) => { + let value_or_partial = self + .owner + .resolver(db.upcast()) + .resolve_path_in_value_ns_fully(db.upcast(), path); + value_or_partial.map_or(true, |v| !matches!(v, ValueNs::StaticId(_))) + } + Expr::Field { expr, .. } => match self.infer.type_of_expr[*expr].kind(Interner) { + TyKind::Adt(adt, ..) + if db.adt_datum(self.owner.krate(db.upcast()), *adt).kind == AdtKind::Union => + { + false + } + _ => self.is_known_valid_scrutinee(*expr, db), + }, + Expr::Index { base, .. } => self.is_known_valid_scrutinee(*base, db), + Expr::Cast { expr, .. } => self.is_known_valid_scrutinee(*expr, db), + Expr::Missing => false, + _ => true, + } + } + fn validate_block(&mut self, db: &dyn HirDatabase, expr: &Expr) { let (Expr::Block { statements, .. } | Expr::Async { statements, .. } @@ -285,7 +334,7 @@ fn validate_block(&mut self, db: &dyn HirDatabase, expr: &Expr) { has_guard: false, arm_data: (), }; - let report = match cx.compute_match_usefulness(&[match_arm], ty.clone()) { + let report = match cx.compute_match_usefulness(&[match_arm], ty.clone(), None) { Ok(v) => v, Err(e) => { debug!(?e, "match usefulness error"); diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/match_check/pat_analysis.rs b/src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/match_check/pat_analysis.rs index a12e201cf3d..b57e290b482 100644 --- a/src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/match_check/pat_analysis.rs +++ b/src/tools/rust-analyzer/crates/hir-ty/src/diagnostics/match_check/pat_analysis.rs @@ -69,22 +69,20 @@ pub(crate) struct MatchCheckCtx<'db> { body: DefWithBodyId, pub(crate) db: &'db dyn HirDatabase, exhaustive_patterns: bool, - min_exhaustive_patterns: bool, } impl<'db> MatchCheckCtx<'db> { pub(crate) fn new(module: ModuleId, body: DefWithBodyId, db: &'db dyn HirDatabase) -> Self { let def_map = db.crate_def_map(module.krate()); let exhaustive_patterns = def_map.is_unstable_feature_enabled(&sym::exhaustive_patterns); - let min_exhaustive_patterns = - def_map.is_unstable_feature_enabled(&sym::min_exhaustive_patterns); - Self { module, body, db, exhaustive_patterns, min_exhaustive_patterns } + Self { module, body, db, exhaustive_patterns } } pub(crate) fn compute_match_usefulness( &self, arms: &[MatchArm<'db>], scrut_ty: Ty, + known_valid_scrutinee: Option, ) -> Result, ()> { if scrut_ty.contains_unknown() { return Err(()); @@ -95,8 +93,7 @@ pub(crate) fn compute_match_usefulness( } } - // FIXME: Determine place validity correctly. For now, err on the safe side. - let place_validity = PlaceValidity::MaybeInvalid; + let place_validity = PlaceValidity::from_bool(known_valid_scrutinee.unwrap_or(true)); // Measured to take ~100ms on modern hardware. let complexity_limit = Some(500000); compute_match_usefulness(self, arms, scrut_ty, place_validity, complexity_limit) @@ -328,7 +325,7 @@ fn is_exhaustive_patterns_feature_on(&self) -> bool { self.exhaustive_patterns } fn is_min_exhaustive_patterns_feature_on(&self) -> bool { - self.min_exhaustive_patterns + true } fn ctor_arity( diff --git a/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/missing_match_arms.rs b/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/missing_match_arms.rs index 97296278c3a..f39738f2fb8 100644 --- a/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/missing_match_arms.rs +++ b/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/missing_match_arms.rs @@ -1032,6 +1032,44 @@ fn exponential_match() { check_diagnostics_no_bails(&code); } + #[test] + fn min_exhaustive() { + check_diagnostics( + r#" +//- minicore: result +fn test(x: Result) { + match x { + Ok(_y) => {} + } +} +"#, + ); + check_diagnostics( + r#" +//- minicore: result +fn test(ptr: *const Result) { + unsafe { + match *ptr { + //^^^^ error: missing match arm: `Err(!)` not covered + Ok(_x) => {} + } + } +} +"#, + ); + check_diagnostics( + r#" +//- minicore: result +fn test(x: Result) { + match x { + //^ error: missing match arm: `Err(_)` not covered + Ok(_y) => {} + } +} +"#, + ); + } + mod rust_unstable { use super::*; diff --git a/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/non_exhaustive_let.rs b/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/non_exhaustive_let.rs index 5a6977c2553..9aace992ae1 100644 --- a/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/non_exhaustive_let.rs +++ b/src/tools/rust-analyzer/crates/ide-diagnostics/src/handlers/non_exhaustive_let.rs @@ -80,6 +80,38 @@ fn main() { //^^^^ error: non-exhaustive pattern: `Some(_)` not covered } } +"# + ); + } + + #[test] + fn min_exhaustive() { + check_diagnostics( + r#" +//- minicore: result +fn test(x: Result) { + let Ok(_y) = x; +} +"#, + ); + check_diagnostics( + r#" +//- minicore: result +fn test(ptr: *const Result) { + unsafe { + let Ok(_x) = *ptr; + //^^^^^^ error: non-exhaustive pattern: `Err(_)` not covered + } +} +"#, + ); + check_diagnostics( + r#" +//- minicore: result +fn test(x: Result) { + let Ok(_y) = x; + //^^^^^^ error: non-exhaustive pattern: `Err(_)` not covered +} "#, ); }