diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_ast_lowering/src/pat.rs | 37 | ||||
| -rw-r--r-- | compiler/rustc_ast_passes/src/ast_validation.rs | 47 |
2 files changed, 34 insertions, 50 deletions
diff --git a/compiler/rustc_ast_lowering/src/pat.rs b/compiler/rustc_ast_lowering/src/pat.rs index 0a9b264aa42..ebae7798433 100644 --- a/compiler/rustc_ast_lowering/src/pat.rs +++ b/compiler/rustc_ast_lowering/src/pat.rs @@ -24,7 +24,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { let lower_sub = |this: &mut Self| sub.as_ref().map(|s| this.lower_pat(&*s)); break self.lower_pat_ident(pattern, binding_mode, ident, lower_sub); } - PatKind::Lit(ref e) => break hir::PatKind::Lit(self.lower_expr(e)), + PatKind::Lit(ref e) => { + break hir::PatKind::Lit(self.lower_expr_within_pat(e, false)); + } PatKind::TupleStruct(ref qself, ref path, ref pats) => { let qpath = self.lower_qpath( pattern.id, @@ -81,8 +83,8 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { } PatKind::Range(ref e1, ref e2, Spanned { node: ref end, .. }) => { break hir::PatKind::Range( - e1.as_deref().map(|e| self.lower_expr(e)), - e2.as_deref().map(|e| self.lower_expr(e)), + e1.as_deref().map(|e| self.lower_expr_within_pat(e, true)), + e2.as_deref().map(|e| self.lower_expr_within_pat(e, true)), self.lower_range_end(end, e2.is_some()), ); } @@ -314,4 +316,33 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { RangeEnd::Excluded | RangeEnd::Included(_) => hir::RangeEnd::Included, } } + + /// Matches `'-' lit | lit (cf. parser::Parser::parse_literal_maybe_minus)`, + /// or paths for ranges. + // + // FIXME: do we want to allow `expr -> pattern` conversion to create path expressions? + // That means making this work: + // + // ```rust,ignore (FIXME) + // struct S; + // macro_rules! m { + // ($a:expr) => { + // let $a = S; + // } + // } + // m!(S); + // ``` + fn lower_expr_within_pat(&mut self, expr: &Expr, allow_paths: bool) -> &'hir hir::Expr<'hir> { + match expr.kind { + ExprKind::Lit(..) | ExprKind::ConstBlock(..) | ExprKind::Err => {} + ExprKind::Path(..) if allow_paths => {} + ExprKind::Unary(UnOp::Neg, ref inner) if matches!(inner.kind, ExprKind::Lit(_)) => {} + _ => { + self.diagnostic() + .span_err(expr.span, "arbitrary expressions aren't allowed in patterns"); + return self.arena.alloc(self.expr_err(expr.span)); + } + } + self.lower_expr(expr) + } } diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs index 3c3ea2bfd35..6237a01f694 100644 --- a/compiler/rustc_ast_passes/src/ast_validation.rs +++ b/compiler/rustc_ast_passes/src/ast_validation.rs @@ -302,34 +302,6 @@ impl<'a> AstValidator<'a> { } } - /// Matches `'-' lit | lit (cf. parser::Parser::parse_literal_maybe_minus)`, - /// or paths for ranges. - // - // FIXME: do we want to allow `expr -> pattern` conversion to create path expressions? - // That means making this work: - // - // ```rust,ignore (FIXME) - // struct S; - // macro_rules! m { - // ($a:expr) => { - // let $a = S; - // } - // } - // m!(S); - // ``` - fn check_expr_within_pat(&self, expr: &Expr, allow_paths: bool) { - match expr.kind { - ExprKind::Lit(..) | ExprKind::ConstBlock(..) | ExprKind::Err => {} - ExprKind::Path(..) if allow_paths => {} - ExprKind::Unary(UnOp::Neg, ref inner) if matches!(inner.kind, ExprKind::Lit(_)) => {} - _ => self.err_handler().span_err( - expr.span, - "arbitrary expressions aren't allowed \ - in patterns", - ), - } - } - fn check_late_bound_lifetime_defs(&self, params: &[GenericParam]) { // Check only lifetime parameters are present and that the lifetime // parameters that are present have no bounds. @@ -1426,25 +1398,6 @@ impl<'a> Visitor<'a> for AstValidator<'a> { visit::walk_param_bound(self, bound) } - fn visit_pat(&mut self, pat: &'a Pat) { - match &pat.kind { - PatKind::Lit(expr) => { - self.check_expr_within_pat(expr, false); - } - PatKind::Range(start, end, _) => { - if let Some(expr) = start { - self.check_expr_within_pat(expr, true); - } - if let Some(expr) = end { - self.check_expr_within_pat(expr, true); - } - } - _ => {} - } - - visit::walk_pat(self, pat) - } - fn visit_poly_trait_ref(&mut self, t: &'a PolyTraitRef, m: &'a TraitBoundModifier) { self.check_late_bound_lifetime_defs(&t.bound_generic_params); visit::walk_poly_trait_ref(self, t, m); |