From ddcb370bc6c2de76c2a2f8b6cfb46a7b6ec553e6 Mon Sep 17 00:00:00 2001 From: Nicholas Nethercote Date: Fri, 20 Dec 2024 10:15:05 +1100 Subject: Tighten up assignment operator representations. In the AST, currently we use `BinOpKind` within `ExprKind::AssignOp` and `AssocOp::AssignOp`, even though this allows some nonsensical combinations. E.g. there is no `&&=` operator. Likewise for HIR and THIR. This commit introduces `AssignOpKind` which only includes the ten assignable operators, and uses it in `ExprKind::AssignOp` and `AssocOp::AssignOp`. (And does similar things for `hir::ExprKind` and `thir::ExprKind`.) This avoids the possibility of nonsensical combinations, as seen by the removal of the `bug!` case in `lang_item_for_binop`. The commit is mostly plumbing, including: - Adds an `impl From for BinOpKind` (AST) and `impl From for BinOp` (MIR/THIR). - `BinOpCategory` can now be created from both `BinOpKind` and `AssignOpKind`. - Replaces the `IsAssign` type with `Op`, which has more information and a few methods. - `suggest_swapping_lhs_and_rhs`: moves the condition to the call site, it's easier that way. - `check_expr_inner`: had to factor out some code into a separate method. I'm on the fence about whether avoiding the nonsensical combinations is worth the extra code. --- compiler/rustc_parse/src/parser/expr.rs | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'compiler/rustc_parse/src/parser') diff --git a/compiler/rustc_parse/src/parser/expr.rs b/compiler/rustc_parse/src/parser/expr.rs index e1e6b93abf3..841d967d934 100644 --- a/compiler/rustc_parse/src/parser/expr.rs +++ b/compiler/rustc_parse/src/parser/expr.rs @@ -14,10 +14,10 @@ use rustc_ast::util::classify; use rustc_ast::util::parser::{AssocOp, ExprPrecedence, Fixity, prec_let_scrutinee_needs_par}; use rustc_ast::visit::{Visitor, walk_expr}; use rustc_ast::{ - self as ast, AnonConst, Arm, AttrStyle, AttrVec, BinOp, BinOpKind, BlockCheckMode, CaptureBy, - ClosureBinder, DUMMY_NODE_ID, Expr, ExprField, ExprKind, FnDecl, FnRetTy, Label, MacCall, - MetaItemLit, Movability, Param, RangeLimits, StmtKind, Ty, TyKind, UnOp, UnsafeBinderCastKind, - YieldKind, + self as ast, AnonConst, Arm, AssignOp, AssignOpKind, AttrStyle, AttrVec, BinOp, BinOpKind, + BlockCheckMode, CaptureBy, ClosureBinder, DUMMY_NODE_ID, Expr, ExprField, ExprKind, FnDecl, + FnRetTy, Label, MacCall, MetaItemLit, Movability, Param, RangeLimits, StmtKind, Ty, TyKind, + UnOp, UnsafeBinderCastKind, YieldKind, }; use rustc_data_structures::stack::ensure_sufficient_stack; use rustc_errors::{Applicability, Diag, PResult, StashKey, Subdiagnostic}; @@ -359,7 +359,7 @@ impl<'a> Parser<'a> { ( Some( AssocOp::Binary(BinOpKind::Shr | BinOpKind::Gt | BinOpKind::Ge) - | AssocOp::AssignOp(BinOpKind::Shr), + | AssocOp::AssignOp(AssignOpKind::ShrAssign), ), _, ) if self.restrictions.contains(Restrictions::CONST_EXPR) => { @@ -3914,8 +3914,8 @@ impl<'a> Parser<'a> { self.dcx().emit_err(errors::LeftArrowOperator { span }); } - fn mk_assign_op(&self, binop: BinOp, lhs: P, rhs: P) -> ExprKind { - ExprKind::AssignOp(binop, lhs, rhs) + fn mk_assign_op(&self, assign_op: AssignOp, lhs: P, rhs: P) -> ExprKind { + ExprKind::AssignOp(assign_op, lhs, rhs) } fn mk_range( -- cgit 1.4.1-3-g733a5