diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_hir_typeck/src/_match.rs | 99 | ||||
| -rw-r--r-- | compiler/rustc_hir_typeck/src/coercion.rs | 46 | ||||
| -rw-r--r-- | compiler/rustc_hir_typeck/src/expr.rs | 14 | ||||
| -rw-r--r-- | compiler/rustc_infer/src/infer/mod.rs | 15 | ||||
| -rw-r--r-- | compiler/rustc_middle/src/traits/mod.rs | 18 | ||||
| -rw-r--r-- | compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs | 61 | ||||
| -rw-r--r-- | compiler/rustc_trait_selection/src/error_reporting/infer/note_and_explain.rs | 42 | ||||
| -rw-r--r-- | compiler/rustc_trait_selection/src/error_reporting/infer/suggest.rs | 24 |
8 files changed, 132 insertions, 187 deletions
diff --git a/compiler/rustc_hir_typeck/src/_match.rs b/compiler/rustc_hir_typeck/src/_match.rs index 4ac260cb15f..6467adb54da 100644 --- a/compiler/rustc_hir_typeck/src/_match.rs +++ b/compiler/rustc_hir_typeck/src/_match.rs @@ -1,12 +1,12 @@ use rustc_errors::{Applicability, Diag}; use rustc_hir::def::{CtorOf, DefKind, Res}; use rustc_hir::def_id::LocalDefId; -use rustc_hir::{self as hir, ExprKind, PatKind}; +use rustc_hir::{self as hir, ExprKind, HirId, PatKind}; use rustc_hir_pretty::ty_to_string; use rustc_middle::ty::{self, Ty}; use rustc_span::Span; use rustc_trait_selection::traits::{ - IfExpressionCause, MatchExpressionArmCause, ObligationCause, ObligationCauseCode, + MatchExpressionArmCause, ObligationCause, ObligationCauseCode, }; use tracing::{debug, instrument}; @@ -414,105 +414,16 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { pub(crate) fn if_cause( &self, - span: Span, - cond_span: Span, - then_expr: &'tcx hir::Expr<'tcx>, + expr_id: HirId, else_expr: &'tcx hir::Expr<'tcx>, - then_ty: Ty<'tcx>, - else_ty: Ty<'tcx>, tail_defines_return_position_impl_trait: Option<LocalDefId>, ) -> ObligationCause<'tcx> { - let mut outer_span = if self.tcx.sess.source_map().is_multiline(span) { - // The `if`/`else` isn't in one line in the output, include some context to make it - // clear it is an if/else expression: - // ``` - // LL | let x = if true { - // | _____________- - // LL || 10i32 - // || ----- expected because of this - // LL || } else { - // LL || 10u32 - // || ^^^^^ expected `i32`, found `u32` - // LL || }; - // ||_____- `if` and `else` have incompatible types - // ``` - Some(span) - } else { - // The entire expression is in one line, only point at the arms - // ``` - // LL | let x = if true { 10i32 } else { 10u32 }; - // | ----- ^^^^^ expected `i32`, found `u32` - // | | - // | expected because of this - // ``` - None - }; - - let (error_sp, else_id) = if let ExprKind::Block(block, _) = &else_expr.kind { - let block = block.innermost_block(); - - // Avoid overlapping spans that aren't as readable: - // ``` - // 2 | let x = if true { - // | _____________- - // 3 | | 3 - // | | - expected because of this - // 4 | | } else { - // | |____________^ - // 5 | || - // 6 | || }; - // | || ^ - // | ||_____| - // | |______if and else have incompatible types - // | expected integer, found `()` - // ``` - // by not pointing at the entire expression: - // ``` - // 2 | let x = if true { - // | ------- `if` and `else` have incompatible types - // 3 | 3 - // | - expected because of this - // 4 | } else { - // | ____________^ - // 5 | | - // 6 | | }; - // | |_____^ expected integer, found `()` - // ``` - if block.expr.is_none() - && block.stmts.is_empty() - && let Some(outer_span) = &mut outer_span - && let Some(cond_span) = cond_span.find_ancestor_inside(*outer_span) - { - *outer_span = outer_span.with_hi(cond_span.hi()) - } - - (self.find_block_span(block), block.hir_id) - } else { - (else_expr.span, else_expr.hir_id) - }; - - let then_id = if let ExprKind::Block(block, _) = &then_expr.kind { - let block = block.innermost_block(); - // Exclude overlapping spans - if block.expr.is_none() && block.stmts.is_empty() { - outer_span = None; - } - block.hir_id - } else { - then_expr.hir_id - }; + let error_sp = self.find_block_span_from_hir_id(else_expr.hir_id); // Finally construct the cause: self.cause( error_sp, - ObligationCauseCode::IfExpression(Box::new(IfExpressionCause { - else_id, - then_id, - then_ty, - else_ty, - outer_span, - tail_defines_return_position_impl_trait, - })), + ObligationCauseCode::IfExpression { expr_id, tail_defines_return_position_impl_trait }, ) } diff --git a/compiler/rustc_hir_typeck/src/coercion.rs b/compiler/rustc_hir_typeck/src/coercion.rs index 0ce0bc313c7..a9367415263 100644 --- a/compiler/rustc_hir_typeck/src/coercion.rs +++ b/compiler/rustc_hir_typeck/src/coercion.rs @@ -46,8 +46,7 @@ use rustc_hir_analysis::hir_ty_lowering::HirTyLowerer; use rustc_infer::infer::relate::RelateResult; use rustc_infer::infer::{Coercion, DefineOpaqueTypes, InferOk, InferResult}; use rustc_infer::traits::{ - IfExpressionCause, ImplSource, MatchExpressionArmCause, Obligation, PredicateObligation, - PredicateObligations, SelectionError, + MatchExpressionArmCause, Obligation, PredicateObligation, PredicateObligations, SelectionError, }; use rustc_middle::span_bug; use rustc_middle::ty::adjustment::{ @@ -59,7 +58,7 @@ use rustc_span::{BytePos, DUMMY_SP, DesugaringKind, Span}; use rustc_trait_selection::infer::InferCtxtExt as _; use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt; use rustc_trait_selection::traits::{ - self, NormalizeExt, ObligationCause, ObligationCauseCode, ObligationCtxt, + self, ImplSource, NormalizeExt, ObligationCause, ObligationCauseCode, ObligationCtxt, }; use smallvec::{SmallVec, smallvec}; use tracing::{debug, instrument}; @@ -1719,14 +1718,17 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> { ); } } - ObligationCauseCode::IfExpression(box IfExpressionCause { - then_id, - else_id, - then_ty, - else_ty, + ObligationCauseCode::IfExpression { + expr_id, tail_defines_return_position_impl_trait: Some(rpit_def_id), - .. - }) => { + } => { + let hir::Node::Expr(hir::Expr { + kind: hir::ExprKind::If(_, then_expr, Some(else_expr)), + .. + }) = fcx.tcx.hir_node(expr_id) + else { + unreachable!(); + }; err = fcx.err_ctxt().report_mismatched_types( cause, fcx.param_env, @@ -1734,24 +1736,12 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> { found, coercion_error, ); - let then_span = fcx.find_block_span_from_hir_id(then_id); - let else_span = fcx.find_block_span_from_hir_id(else_id); - // don't suggest wrapping either blocks in `if .. {} else {}` - let is_empty_arm = |id| { - let hir::Node::Block(blk) = fcx.tcx.hir_node(id) else { - return false; - }; - if blk.expr.is_some() || !blk.stmts.is_empty() { - return false; - } - let Some((_, hir::Node::Expr(expr))) = - fcx.tcx.hir_parent_iter(id).nth(1) - else { - return false; - }; - matches!(expr.kind, hir::ExprKind::If(..)) - }; - if !is_empty_arm(then_id) && !is_empty_arm(else_id) { + let then_span = fcx.find_block_span_from_hir_id(then_expr.hir_id); + let else_span = fcx.find_block_span_from_hir_id(else_expr.hir_id); + // Don't suggest wrapping whole block in `Box::new`. + if then_span != then_expr.span && else_span != else_expr.span { + let then_ty = fcx.typeck_results.borrow().expr_ty(then_expr); + let else_ty = fcx.typeck_results.borrow().expr_ty(else_expr); self.suggest_boxing_tail_for_return_position_impl_trait( fcx, &mut err, diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs index 2bc9dadb665..3a0d57dca12 100644 --- a/compiler/rustc_hir_typeck/src/expr.rs +++ b/compiler/rustc_hir_typeck/src/expr.rs @@ -583,7 +583,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { ascribed_ty } ExprKind::If(cond, then_expr, opt_else_expr) => { - self.check_expr_if(cond, then_expr, opt_else_expr, expr.span, expected) + self.check_expr_if(expr.hir_id, cond, then_expr, opt_else_expr, expr.span, expected) } ExprKind::DropTemps(e) => self.check_expr_with_expectation(e, expected), ExprKind::Array(args) => self.check_expr_array(args, expected, expr), @@ -1343,6 +1343,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { // or 'if-else' expression. fn check_expr_if( &self, + expr_id: HirId, cond_expr: &'tcx hir::Expr<'tcx>, then_expr: &'tcx hir::Expr<'tcx>, opt_else_expr: Option<&'tcx hir::Expr<'tcx>>, @@ -1382,15 +1383,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { let tail_defines_return_position_impl_trait = self.return_position_impl_trait_from_match_expectation(orig_expected); - let if_cause = self.if_cause( - sp, - cond_expr.span, - then_expr, - else_expr, - then_ty, - else_ty, - tail_defines_return_position_impl_trait, - ); + let if_cause = + self.if_cause(expr_id, else_expr, tail_defines_return_position_impl_trait); coerce.coerce(self, &if_cause, else_expr, else_ty); diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs index e9b58eb959b..491efba9eb0 100644 --- a/compiler/rustc_infer/src/infer/mod.rs +++ b/compiler/rustc_infer/src/infer/mod.rs @@ -35,7 +35,7 @@ use rustc_middle::ty::{ PseudoCanonicalInput, Term, TermKind, Ty, TyCtxt, TyVid, TypeFoldable, TypeFolder, TypeSuperFoldable, TypeVisitable, TypeVisitableExt, TypingEnv, TypingMode, fold_regions, }; -use rustc_span::{Span, Symbol}; +use rustc_span::{DUMMY_SP, Span, Symbol}; use snapshot::undo_log::InferCtxtUndoLogs; use tracing::{debug, instrument}; use type_variable::TypeVariableOrigin; @@ -1557,15 +1557,16 @@ impl<'tcx> InferCtxt<'tcx> { } } - /// Given a [`hir::HirId`] for a block, get the span of its last expression - /// or statement, peeling off any inner blocks. + /// Given a [`hir::HirId`] for a block (or an expr of a block), get the span + /// of its last expression or statement, peeling off any inner blocks. pub fn find_block_span_from_hir_id(&self, hir_id: hir::HirId) -> Span { match self.tcx.hir_node(hir_id) { - hir::Node::Block(blk) => self.find_block_span(blk), - // The parser was in a weird state if either of these happen, but - // it's better not to panic. + hir::Node::Block(blk) + | hir::Node::Expr(&hir::Expr { kind: hir::ExprKind::Block(blk, _), .. }) => { + self.find_block_span(blk) + } hir::Node::Expr(e) => e.span, - _ => rustc_span::DUMMY_SP, + _ => DUMMY_SP, } } } diff --git a/compiler/rustc_middle/src/traits/mod.rs b/compiler/rustc_middle/src/traits/mod.rs index d877bd5c626..1a5a9765ce7 100644 --- a/compiler/rustc_middle/src/traits/mod.rs +++ b/compiler/rustc_middle/src/traits/mod.rs @@ -332,7 +332,11 @@ pub enum ObligationCauseCode<'tcx> { }, /// Computing common supertype in an if expression - IfExpression(Box<IfExpressionCause<'tcx>>), + IfExpression { + expr_id: HirId, + // Is the expectation of this match expression an RPIT? + tail_defines_return_position_impl_trait: Option<LocalDefId>, + }, /// Computing common supertype of an if expression with no else counter-part IfExpressionWithNoElse, @@ -550,18 +554,6 @@ pub struct PatternOriginExpr { pub peeled_prefix_suggestion_parentheses: bool, } -#[derive(Copy, Clone, Debug, PartialEq, Eq)] -#[derive(TypeFoldable, TypeVisitable, HashStable, TyEncodable, TyDecodable)] -pub struct IfExpressionCause<'tcx> { - pub then_id: HirId, - pub else_id: HirId, - pub then_ty: Ty<'tcx>, - pub else_ty: Ty<'tcx>, - pub outer_span: Option<Span>, - // Is the expectation of this match expression an RPIT? - pub tail_defines_return_position_impl_trait: Option<LocalDefId>, -} - #[derive(Clone, Debug, PartialEq, Eq, HashStable, TyEncodable, TyDecodable)] #[derive(TypeVisitable, TypeFoldable)] pub struct DerivedCause<'tcx> { diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs index 2c16672d786..bc464b099e2 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs @@ -82,9 +82,7 @@ use crate::infer; use crate::infer::relate::{self, RelateResult, TypeRelation}; use crate::infer::{InferCtxt, InferCtxtExt as _, TypeTrace, ValuePairs}; use crate::solve::deeply_normalize_for_diagnostics; -use crate::traits::{ - IfExpressionCause, MatchExpressionArmCause, ObligationCause, ObligationCauseCode, -}; +use crate::traits::{MatchExpressionArmCause, ObligationCause, ObligationCauseCode}; mod note_and_explain; mod suggest; @@ -613,18 +611,28 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { } } }, - ObligationCauseCode::IfExpression(box IfExpressionCause { - then_id, - else_id, - then_ty, - else_ty, - outer_span, - .. - }) => { - let then_span = self.find_block_span_from_hir_id(then_id); - let else_span = self.find_block_span_from_hir_id(else_id); - if let hir::Node::Expr(e) = self.tcx.hir_node(else_id) - && let hir::ExprKind::If(_cond, _then, None) = e.kind + ObligationCauseCode::IfExpression { expr_id, .. } => { + let hir::Node::Expr(&hir::Expr { + kind: hir::ExprKind::If(cond_expr, then_expr, Some(else_expr)), + span: expr_span, + .. + }) = self.tcx.hir_node(expr_id) + else { + return; + }; + let then_span = self.find_block_span_from_hir_id(then_expr.hir_id); + let then_ty = self + .typeck_results + .as_ref() + .expect("if expression only expected inside FnCtxt") + .expr_ty(then_expr); + let else_span = self.find_block_span_from_hir_id(else_expr.hir_id); + let else_ty = self + .typeck_results + .as_ref() + .expect("if expression only expected inside FnCtxt") + .expr_ty(else_expr); + if let hir::ExprKind::If(_cond, _then, None) = else_expr.kind && else_ty.is_unit() { // Account for `let x = if a { 1 } else if b { 2 };` @@ -632,9 +640,32 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> { err.note("consider adding an `else` block that evaluates to the expected type"); } err.span_label(then_span, "expected because of this"); + + let outer_span = if self.tcx.sess.source_map().is_multiline(expr_span) { + if then_span.hi() == expr_span.hi() || else_span.hi() == expr_span.hi() { + // Point at condition only if either block has the same end point as + // the whole expression, since that'll cause awkward overlapping spans. + Some(expr_span.shrink_to_lo().to(cond_expr.peel_drop_temps().span)) + } else { + Some(expr_span) + } + } else { + None + }; if let Some(sp) = outer_span { err.span_label(sp, "`if` and `else` have incompatible types"); } + + let then_id = if let hir::ExprKind::Block(then_blk, _) = then_expr.kind { + then_blk.hir_id + } else { + then_expr.hir_id + }; + let else_id = if let hir::ExprKind::Block(else_blk, _) = else_expr.kind { + else_blk.hir_id + } else { + else_expr.hir_id + }; if let Some(subdiag) = self.suggest_remove_semi_or_return_binding( Some(then_id), then_ty, diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/note_and_explain.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/note_and_explain.rs index be508c8cee1..0a4a9144c94 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/infer/note_and_explain.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/infer/note_and_explain.rs @@ -420,19 +420,33 @@ impl<T> Trait<T> for X { } // If two if arms can be coerced to a trait object, provide a structured // suggestion. - let ObligationCauseCode::IfExpression(cause) = cause.code() else { + let ObligationCauseCode::IfExpression { expr_id, .. } = cause.code() else { return; }; - let hir::Node::Block(blk) = self.tcx.hir_node(cause.then_id) else { - return; - }; - let Some(then) = blk.expr else { - return; - }; - let hir::Node::Block(blk) = self.tcx.hir_node(cause.else_id) else { - return; - }; - let Some(else_) = blk.expr else { + let hir::Node::Expr(&hir::Expr { + kind: + hir::ExprKind::If( + _, + &hir::Expr { + kind: + hir::ExprKind::Block( + &hir::Block { expr: Some(then), .. }, + _, + ), + .. + }, + Some(&hir::Expr { + kind: + hir::ExprKind::Block( + &hir::Block { expr: Some(else_), .. }, + _, + ), + .. + }), + ), + .. + }) = self.tcx.hir_node(*expr_id) + else { return; }; let expected = match values.found.kind() { @@ -486,8 +500,10 @@ impl<T> Trait<T> for X { } } (ty::Adt(_, _), ty::Adt(def, args)) - if let ObligationCauseCode::IfExpression(cause) = cause.code() - && let hir::Node::Block(blk) = self.tcx.hir_node(cause.then_id) + if let ObligationCauseCode::IfExpression { expr_id, .. } = cause.code() + && let hir::Node::Expr(if_expr) = self.tcx.hir_node(*expr_id) + && let hir::ExprKind::If(_, then_expr, _) = if_expr.kind + && let hir::ExprKind::Block(blk, _) = then_expr.kind && let Some(then) = blk.expr && def.is_box() && let boxed_ty = args.type_at(0) diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/suggest.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/suggest.rs index 3804c13acce..c0daf08ce07 100644 --- a/compiler/rustc_trait_selection/src/error_reporting/infer/suggest.rs +++ b/compiler/rustc_trait_selection/src/error_reporting/infer/suggest.rs @@ -8,9 +8,7 @@ use rustc_errors::{Applicability, Diag}; use rustc_hir as hir; use rustc_hir::def::Res; use rustc_hir::{MatchSource, Node}; -use rustc_middle::traits::{ - IfExpressionCause, MatchExpressionArmCause, ObligationCause, ObligationCauseCode, -}; +use rustc_middle::traits::{MatchExpressionArmCause, ObligationCause, ObligationCauseCode}; use rustc_middle::ty::error::TypeError; use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::{self as ty, GenericArgKind, IsSuggestable, Ty, TypeVisitableExt}; @@ -196,8 +194,14 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { (Some(exp), Some(found)) if self.same_type_modulo_infer(exp, found) => match cause .code() { - ObligationCauseCode::IfExpression(box IfExpressionCause { then_id, .. }) => { - let then_span = self.find_block_span_from_hir_id(*then_id); + ObligationCauseCode::IfExpression { expr_id, .. } => { + let hir::Node::Expr(hir::Expr { + kind: hir::ExprKind::If(_, then_expr, _), .. + }) = self.tcx.hir_node(*expr_id) + else { + return; + }; + let then_span = self.find_block_span_from_hir_id(then_expr.hir_id); Some(ConsiderAddingAwait::BothFuturesSugg { first: then_span.shrink_to_hi(), second: exp_span.shrink_to_hi(), @@ -232,8 +236,14 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { span: then_span.shrink_to_hi(), }) } - ObligationCauseCode::IfExpression(box IfExpressionCause { then_id, .. }) => { - let then_span = self.find_block_span_from_hir_id(*then_id); + ObligationCauseCode::IfExpression { expr_id, .. } => { + let hir::Node::Expr(hir::Expr { + kind: hir::ExprKind::If(_, then_expr, _), .. + }) = self.tcx.hir_node(*expr_id) + else { + return; + }; + let then_span = self.find_block_span_from_hir_id(then_expr.hir_id); Some(ConsiderAddingAwait::FutureSugg { span: then_span.shrink_to_hi() }) } ObligationCauseCode::MatchExpressionArm(box MatchExpressionArmCause { |