Revert "Teach parser to understand fake anonymous enum syntax" and related commits

Revert "review comment: Remove AST AnonTy"

This reverts commit 020cca8d36.

Revert "Ensure macros are not affected"

This reverts commit 12d18e4031.

Revert "Emit fewer errors on patterns with possible type ascription"

This reverts commit c847a01a3b.

Revert "Teach parser to understand fake anonymous enum syntax"

This reverts commit 2d82420665.
This commit is contained in:
Michael Goulet 2023-01-30 18:08:50 +00:00
parent 131f0c6df6
commit e4b2936983
9 changed files with 47 additions and 266 deletions

View file

@ -2394,7 +2394,7 @@ impl<'a> Parser<'a> {
/// Some special error handling for the "top-level" patterns in a match arm,
/// `for` loop, `let`, &c. (in contrast to subpatterns within such).
pub(crate) fn maybe_recover_colon_colon_in_pat_typo_or_anon_enum(
pub(crate) fn maybe_recover_colon_colon_in_pat_typo(
&mut self,
mut first_pat: P<Pat>,
expected: Option<Expected>,
@ -2405,41 +2405,26 @@ impl<'a> Parser<'a> {
if !matches!(first_pat.kind, PatKind::Ident(_, _, None) | PatKind::Path(..))
|| !self.look_ahead(1, |token| token.is_ident() && !token.is_reserved_ident())
{
let mut snapshot_type = self.create_snapshot_for_diagnostic();
snapshot_type.bump(); // `:`
match snapshot_type.parse_ty() {
Err(inner_err) => {
inner_err.cancel();
}
Ok(ty) => {
let Err(mut err) = self.expected_one_of_not_found(&[], &[]) else {
return first_pat;
};
err.span_label(ty.span, "specifying the type of a pattern isn't supported");
self.restore_snapshot(snapshot_type);
let span = first_pat.span.to(ty.span);
first_pat = self.mk_pat(span, PatKind::Wild);
err.emit();
}
}
return first_pat;
}
// The pattern looks like it might be a path with a `::` -> `:` typo:
// `match foo { bar:baz => {} }`
let colon_span = self.token.span;
let span = self.token.span;
// We only emit "unexpected `:`" error here if we can successfully parse the
// whole pattern correctly in that case.
let mut snapshot_pat = self.create_snapshot_for_diagnostic();
let mut snapshot_type = self.create_snapshot_for_diagnostic();
let snapshot = self.create_snapshot_for_diagnostic();
// Create error for "unexpected `:`".
match self.expected_one_of_not_found(&[], &[]) {
Err(mut err) => {
snapshot_pat.bump(); // Skip the `:`.
snapshot_type.bump(); // Skip the `:`.
match snapshot_pat.parse_pat_no_top_alt(expected) {
self.bump(); // Skip the `:`.
match self.parse_pat_no_top_alt(expected) {
Err(inner_err) => {
// Carry on as if we had not done anything, callers will emit a
// reasonable error.
inner_err.cancel();
err.cancel();
self.restore_snapshot(snapshot);
}
Ok(mut pat) => {
// We've parsed the rest of the pattern.
@ -2503,8 +2488,8 @@ impl<'a> Parser<'a> {
_ => {}
}
if show_sugg {
err.span_suggestion_verbose(
colon_span.until(self.look_ahead(1, |t| t.span)),
err.span_suggestion(
span,
"maybe write a path separator here",
"::",
Applicability::MaybeIncorrect,
@ -2512,24 +2497,13 @@ impl<'a> Parser<'a> {
} else {
first_pat = self.mk_pat(new_span, PatKind::Wild);
}
self.restore_snapshot(snapshot_pat);
err.emit();
}
}
match snapshot_type.parse_ty() {
Err(inner_err) => {
inner_err.cancel();
}
Ok(ty) => {
err.span_label(ty.span, "specifying the type of a pattern isn't supported");
self.restore_snapshot(snapshot_type);
let new_span = first_pat.span.to(ty.span);
first_pat = self.mk_pat(new_span, PatKind::Wild);
}
}
err.emit();
}
_ => {
// Carry on as if we had not done anything. This should be unreachable.
self.restore_snapshot(snapshot);
}
};
first_pat