discriminant -> scrutinee

This commit is contained in:
Mazdak Farrokhzad 2019-12-30 12:48:48 +01:00
parent f8d2cce0ce
commit 63dc0e41db
4 changed files with 27 additions and 27 deletions

View file

@ -607,7 +607,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
source,
ref prior_arms,
last_ty,
discrim_hir_id,
scrut_hir_id,
..
}) => match source {
hir::MatchSource::IfLetDesugar { .. } => {
@ -616,16 +616,16 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
}
hir::MatchSource::TryDesugar => {
if let Some(ty::error::ExpectedFound { expected, .. }) = exp_found {
let discrim_expr = self.tcx.hir().expect_expr(discrim_hir_id);
let discrim_ty = if let hir::ExprKind::Call(_, args) = &discrim_expr.kind {
let scrut_expr = self.tcx.hir().expect_expr(scrut_hir_id);
let scrut_ty = if let hir::ExprKind::Call(_, args) = &scrut_expr.kind {
let arg_expr = args.first().expect("try desugaring call w/out arg");
self.in_progress_tables
.and_then(|tables| tables.borrow().expr_ty_opt(arg_expr))
} else {
bug!("try desugaring w/out call expr as discriminant");
bug!("try desugaring w/out call expr as scrutinee");
};
match discrim_ty {
match scrut_ty {
Some(ty) if expected == ty => {
let source_map = self.tcx.sess.source_map();
err.span_suggestion(

View file

@ -315,7 +315,7 @@ pub struct MatchExpressionArmCause<'tcx> {
pub source: hir::MatchSource,
pub prior_arms: Vec<Span>,
pub last_ty: Ty<'tcx>,
pub discrim_hir_id: hir::HirId,
pub scrut_hir_id: hir::HirId,
}
#[derive(Clone, Debug, PartialEq, Eq, Hash)]

View file

@ -511,14 +511,14 @@ impl<'a, 'tcx> Lift<'tcx> for traits::ObligationCauseCode<'a> {
source,
ref prior_arms,
last_ty,
discrim_hir_id,
scrut_hir_id,
}) => tcx.lift(&last_ty).map(|last_ty| {
super::MatchExpressionArm(box super::MatchExpressionArmCause {
arm_span,
source,
prior_arms: prior_arms.clone(),
last_ty,
discrim_hir_id,
scrut_hir_id,
})
}),
super::Pattern { span, root_ty, origin_expr } => {

View file

@ -11,7 +11,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
pub fn check_match(
&self,
expr: &'tcx hir::Expr<'tcx>,
discrim: &'tcx hir::Expr<'tcx>,
scrut: &'tcx hir::Expr<'tcx>,
arms: &'tcx [hir::Arm<'tcx>],
expected: Expectation<'tcx>,
match_src: hir::MatchSource,
@ -27,7 +27,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
};
// Type check the descriminant and get its type.
let discrim_ty = if force_scrutinee_bool {
let scrut_ty = if force_scrutinee_bool {
// Here we want to ensure:
//
// 1. That default match bindings are *not* accepted in the condition of an
@ -36,9 +36,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
// 2. By expecting `bool` for `expr` we get nice diagnostics for e.g. `if x = y { .. }`.
//
// FIXME(60707): Consider removing hack with principled solution.
self.check_expr_has_type_or_error(discrim, self.tcx.types.bool, |_| {})
self.check_expr_has_type_or_error(scrut, self.tcx.types.bool, |_| {})
} else {
self.demand_discriminant_type(arms, discrim)
self.demand_scrutinee_type(arms, scrut)
};
// If there are no arms, that is a diverging match; a special case.
@ -51,7 +51,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
// Otherwise, we have to union together the types that the
// arms produce and so forth.
let discrim_diverges = self.diverges.get();
let scrut_diverges = self.diverges.get();
self.diverges.set(Diverges::Maybe);
// rust-lang/rust#55810: Typecheck patterns first (via eager
@ -61,7 +61,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
.map(|arm| {
let mut all_pats_diverge = Diverges::WarnedAlways;
self.diverges.set(Diverges::Maybe);
self.check_pat_top(&arm.pat, discrim_ty, Some(discrim.span), true);
self.check_pat_top(&arm.pat, scrut_ty, Some(scrut.span), true);
all_pats_diverge &= self.diverges.get();
// As discussed with @eddyb, this is for disabling unreachable_code
@ -157,7 +157,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
source: match_src,
prior_arms: other_arms.clone(),
last_ty: prior_arm_ty.unwrap(),
discrim_hir_id: discrim.hir_id,
scrut_hir_id: scrut.hir_id,
}),
),
};
@ -186,8 +186,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
};
}
// We won't diverge unless the discriminant or all arms diverge.
self.diverges.set(discrim_diverges | all_arms_diverge);
// We won't diverge unless the scrutinee or all arms diverge.
self.diverges.set(scrut_diverges | all_arms_diverge);
coercion.complete(self)
}
@ -388,14 +388,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
)
}
fn demand_discriminant_type(
fn demand_scrutinee_type(
&self,
arms: &'tcx [hir::Arm<'tcx>],
discrim: &'tcx hir::Expr<'tcx>,
scrut: &'tcx hir::Expr<'tcx>,
) -> Ty<'tcx> {
// Not entirely obvious: if matches may create ref bindings, we want to
// use the *precise* type of the discriminant, *not* some supertype, as
// the "discriminant type" (issue #23116).
// use the *precise* type of the scrutinee, *not* some supertype, as
// the "scrutinee type" (issue #23116).
//
// arielb1 [writes here in this comment thread][c] that there
// is certainly *some* potential danger, e.g., for an example
@ -454,17 +454,17 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
});
if let Some(m) = contains_ref_bindings {
self.check_expr_with_needs(discrim, Needs::maybe_mut_place(m))
self.check_expr_with_needs(scrut, Needs::maybe_mut_place(m))
} else {
// ...but otherwise we want to use any supertype of the
// discriminant. This is sort of a workaround, see note (*) in
// scrutinee. This is sort of a workaround, see note (*) in
// `check_pat` for some details.
let discrim_ty = self.next_ty_var(TypeVariableOrigin {
let scrut_ty = self.next_ty_var(TypeVariableOrigin {
kind: TypeVariableOriginKind::TypeInference,
span: discrim.span,
span: scrut.span,
});
self.check_expr_has_type_or_error(discrim, discrim_ty, |_| {});
discrim_ty
self.check_expr_has_type_or_error(scrut, scrut_ty, |_| {});
scrut_ty
}
}
}