bjoernager/rust
bjoernager/rust
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Migrate forbidden_let

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This commit is contained in:
finalchild 2022-08-17 23:51:01 +09:00
parent 4b695f7c4e
commit d6fdf14eb7
7 changed files with 45 additions and 18 deletions
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22
compiler/rustc_ast_passes/src/ast_validation.rs
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@ -27,6 +27,8 @@ use rustc_target::spec::abi;
use std::mem;
use std::ops::{Deref, DerefMut};
use crate::errors::ForbiddenLet;
const MORE_EXTERN: &str =
"for more information, visit https://doc.rust-lang.org/std/keyword.extern.html";
@ -117,23 +119,7 @@ impl<'a> AstValidator<'a> {
/// Emits an error banning the `let` expression provided in the given location.
fn ban_let_expr(&self, expr: &'a Expr, forbidden_let_reason: ForbiddenLetReason) {
let err = "`let` expressions are not supported here";
let mut diag = self.session.struct_span_err(expr.span, err);
diag.note("only supported directly in conditions of `if` and `while` expressions");
match forbidden_let_reason {
ForbiddenLetReason::GenericForbidden => {}
ForbiddenLetReason::NotSupportedOr(span) => {
diag.span_note(span, "`||` operators are not supported in let chain expressions");
}
ForbiddenLetReason::NotSupportedParentheses(span) => {
diag.span_note(
span,
"`let`s wrapped in parentheses are not supported in a context with let \
chains",
);
}
}
diag.emit();
self.session.emit_err(ForbiddenLet { span: expr.span, reason: forbidden_let_reason });
}
fn check_gat_where(
@ -1876,7 +1862,7 @@ pub fn check_crate(session: &Session, krate: &Crate, lints: &mut LintBuffer) ->
/// Used to forbid `let` expressions in certain syntactic locations.
#[derive(Clone, Copy)]
enum ForbiddenLetReason {
pub(crate) enum ForbiddenLetReason {
/// `let` is not valid and the source environment is not important
GenericForbidden,
/// A let chain with the `||` operator