diff options
| -rw-r--r-- | src/librustc/hir/mod.rs | 4 | ||||
| -rw-r--r-- | src/librustc_mir/borrow_check/conflict_errors.rs | 30 | ||||
| -rw-r--r-- | src/librustc_mir/borrow_check/error_reporting.rs | 45 | ||||
| -rw-r--r-- | src/test/ui/async-await/async-borrowck-escaping-block-error.stderr | 2 |
4 files changed, 55 insertions, 26 deletions
diff --git a/src/librustc/hir/mod.rs b/src/librustc/hir/mod.rs index e72f46682ce..7350f89018b 100644 --- a/src/librustc/hir/mod.rs +++ b/src/librustc/hir/mod.rs @@ -1366,6 +1366,10 @@ impl Body { hir_id: self.value.hir_id, } } + + pub fn generator_kind(&self) -> Option<GeneratorKind> { + self.generator_kind + } } /// The type of source expression that caused this generator to be created. diff --git a/src/librustc_mir/borrow_check/conflict_errors.rs b/src/librustc_mir/borrow_check/conflict_errors.rs index 2f9df7bd77e..098258994f4 100644 --- a/src/librustc_mir/borrow_check/conflict_errors.rs +++ b/src/librustc_mir/borrow_check/conflict_errors.rs @@ -1,5 +1,6 @@ use rustc::hir; use rustc::hir::def_id::DefId; +use rustc::hir::{AsyncGeneratorKind, GeneratorKind}; use rustc::mir::{ self, AggregateKind, BindingForm, BorrowKind, ClearCrossCrate, ConstraintCategory, Local, LocalDecl, LocalKind, Location, Operand, Place, PlaceBase, PlaceRef, ProjectionElem, Rvalue, @@ -788,7 +789,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { .. }, ) if borrow_spans.for_closure() => self.report_escaping_closure_capture( - borrow_spans.args_or_use(), + borrow_spans, borrow_span, region_name, category, @@ -806,7 +807,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { }, ) if borrow_spans.for_generator() => self.report_escaping_closure_capture( - borrow_spans.args_or_use(), + borrow_spans, borrow_span, region_name, category, @@ -1195,7 +1196,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { fn report_escaping_closure_capture( &mut self, - args_span: Span, + use_span: UseSpans, var_span: Span, fr_name: &RegionName, category: ConstraintCategory, @@ -1203,7 +1204,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { captured_var: &str, ) -> DiagnosticBuilder<'cx> { let tcx = self.infcx.tcx; - + let args_span = use_span.args_or_use(); let mut err = self.cannot_capture_in_long_lived_closure( args_span, captured_var, @@ -1223,12 +1224,25 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { }, Err(_) => "move |<args>| <body>".to_string() }; - + let kind = match use_span.generator_kind() { + Some(generator_kind) => match generator_kind { + GeneratorKind::Async(async_kind) => match async_kind { + AsyncGeneratorKind::Block => "async block", + AsyncGeneratorKind::Closure => "async closure", + _ => bug!("async block/closure expected, but async funtion found."), + }, + GeneratorKind::Gen => "generator", + } + None => "closure", + }; err.span_suggestion( args_span, - &format!("to force the closure to take ownership of {} (and any \ - other referenced variables), use the `move` keyword", - captured_var), + &format!( + "to force the {} to take ownership of {} (and any \ + other referenced variables), use the `move` keyword", + kind, + captured_var + ), suggestion, Applicability::MachineApplicable, ); diff --git a/src/librustc_mir/borrow_check/error_reporting.rs b/src/librustc_mir/borrow_check/error_reporting.rs index dc7e4b22065..5e0727d5157 100644 --- a/src/librustc_mir/borrow_check/error_reporting.rs +++ b/src/librustc_mir/borrow_check/error_reporting.rs @@ -1,6 +1,7 @@ use rustc::hir; use rustc::hir::def::Namespace; use rustc::hir::def_id::DefId; +use rustc::hir::GeneratorKind; use rustc::mir::{ AggregateKind, Constant, Field, Local, LocalKind, Location, Operand, Place, PlaceBase, PlaceRef, ProjectionElem, Rvalue, Statement, StatementKind, @@ -14,7 +15,7 @@ use syntax_pos::Span; use syntax::symbol::sym; use super::borrow_set::BorrowData; -use super::{MirBorrowckCtxt}; +use super::MirBorrowckCtxt; use crate::dataflow::move_paths::{InitLocation, LookupResult}; pub(super) struct IncludingDowncast(pub(super) bool); @@ -604,7 +605,7 @@ pub(super) enum UseSpans { // The access is caused by capturing a variable for a closure. ClosureUse { // This is true if the captured variable was from a generator. - is_generator: bool, + generator_kind: Option<GeneratorKind>, // The span of the args of the closure, including the `move` keyword if // it's present. args_span: Span, @@ -631,6 +632,13 @@ impl UseSpans { } } + pub(super) fn generator_kind(self) -> Option<GeneratorKind> { + match self { + UseSpans::ClosureUse { generator_kind, .. } => generator_kind, + _ => None, + } + } + // Add a span label to the arguments of the closure, if it exists. pub(super) fn args_span_label( self, @@ -656,7 +664,7 @@ impl UseSpans { /// Returns `false` if this place is not used in a closure. pub(super) fn for_closure(&self) -> bool { match *self { - UseSpans::ClosureUse { is_generator, .. } => !is_generator, + UseSpans::ClosureUse { generator_kind, .. } => generator_kind.is_none(), _ => false, } } @@ -664,7 +672,7 @@ impl UseSpans { /// Returns `false` if this place is not used in a generator. pub(super) fn for_generator(&self) -> bool { match *self { - UseSpans::ClosureUse { is_generator, .. } => is_generator, + UseSpans::ClosureUse { generator_kind, .. } => generator_kind.is_some(), _ => false, } } @@ -672,7 +680,7 @@ impl UseSpans { /// Describe the span associated with a use of a place. pub(super) fn describe(&self) -> String { match *self { - UseSpans::ClosureUse { is_generator, .. } => if is_generator { + UseSpans::ClosureUse { generator_kind, .. } => if generator_kind.is_some() { " in generator".to_string() } else { " in closure".to_string() @@ -794,19 +802,20 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { if let StatementKind::Assign( box(_, Rvalue::Aggregate(ref kind, ref places)) ) = stmt.kind { - let (def_id, is_generator) = match kind { - box AggregateKind::Closure(def_id, _) => (def_id, false), - box AggregateKind::Generator(def_id, _, _) => (def_id, true), + let def_id = match kind { + box AggregateKind::Closure(def_id, _) + | box AggregateKind::Generator(def_id, _, _) => def_id, _ => return OtherUse(stmt.source_info.span), }; debug!( - "move_spans: def_id={:?} is_generator={:?} places={:?}", - def_id, is_generator, places + "move_spans: def_id={:?} places={:?}", + def_id, places ); - if let Some((args_span, var_span)) = self.closure_span(*def_id, moved_place, places) { + if let Some((args_span, generator_kind, var_span)) + = self.closure_span(*def_id, moved_place, places) { return ClosureUse { - is_generator, + generator_kind, args_span, var_span, }; @@ -857,11 +866,11 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { "borrow_spans: def_id={:?} is_generator={:?} places={:?}", def_id, is_generator, places ); - if let Some((args_span, var_span)) = self.closure_span( + if let Some((args_span, generator_kind, var_span)) = self.closure_span( *def_id, Place::from(target).as_ref(), places ) { return ClosureUse { - is_generator, + generator_kind, args_span, var_span, }; @@ -884,7 +893,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { def_id: DefId, target_place: PlaceRef<'cx, 'tcx>, places: &Vec<Operand<'tcx>>, - ) -> Option<(Span, Span)> { + ) -> Option<(Span, Option<GeneratorKind>, Span)> { debug!( "closure_span: def_id={:?} target_place={:?} places={:?}", def_id, target_place, places @@ -893,14 +902,16 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> { let expr = &self.infcx.tcx.hir().expect_expr(hir_id).kind; debug!("closure_span: hir_id={:?} expr={:?}", hir_id, expr); if let hir::ExprKind::Closure( - .., args_span, _ + .., body_id, args_span, _ ) = expr { for (upvar, place) in self.infcx.tcx.upvars(def_id)?.values().zip(places) { match place { Operand::Copy(place) | Operand::Move(place) if target_place == place.as_ref() => { debug!("closure_span: found captured local {:?}", place); - return Some((*args_span, upvar.span)); + let body = self.infcx.tcx.hir().body(*body_id); + let generator_kind = body.generator_kind(); + return Some((*args_span, generator_kind, upvar.span)); }, _ => {} } diff --git a/src/test/ui/async-await/async-borrowck-escaping-block-error.stderr b/src/test/ui/async-await/async-borrowck-escaping-block-error.stderr index af17ecc86fb..0eb3971d14a 100644 --- a/src/test/ui/async-await/async-borrowck-escaping-block-error.stderr +++ b/src/test/ui/async-await/async-borrowck-escaping-block-error.stderr @@ -12,7 +12,7 @@ note: generator is returned here | LL | fn foo() -> Box<impl std::future::Future<Output = u32>> { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -help: to force the closure to take ownership of `x` (and any other referenced variables), use the `move` keyword +help: to force the async block to take ownership of `x` (and any other referenced variables), use the `move` keyword | LL | Box::new(async move { x } ) | ^^^^^^^^^^ |