Make top-level rustc_parse functions fallible.

Currently we have an awkward mix of fallible and infallible functions: ``` new_parser_from_source_str maybe_new_parser_from_source_str new_parser_from_file (maybe_new_parser_from_file) // missing (new_parser_from_source_file) // missing maybe_new_parser_from_source_file source_str_to_stream maybe_source_file_to_stream ``` We could add the two missing functions, but instead this commit removes of all the infallible ones and renames the fallible ones leaving us with these which are all fallible: ``` new_parser_from_source_str new_parser_from_file new_parser_from_source_file source_str_to_stream source_file_to_stream ``` This requires making `unwrap_or_emit_fatal` public so callers of formerly infallible functions can still work. This does make some of the call sites slightly more verbose, but I think it's worth it for the simpler API. Also, there are two `catch_unwind` calls and one `catch_fatal_errors` call in this diff that become removable thanks this change. (I will do that in a follow-up PR.)
rust-lang · Jun 5, 2024 · 5962aa9 · 5962aa9
1 parent eeefcd6
commit 5962aa9
Showing 1 changed file with 6 additions and 4 deletions.
diff --git a/src/parse/parser.rs b/src/parse/parser.rs
@@ -4,7 4,8 @@ use std::path::{Path, PathBuf};
 use rustc_ast::token::TokenKind;
 use rustc_ast::{ast, attr, ptr};
 use rustc_errors::Diag;
-use rustc_parse::{new_parser_from_file, parser::Parser as RawParser};
 use rustc_parse::parser::Parser as RawParser;
 use rustc_parse::{new_parser_from_file, unwrap_or_emit_fatal};
 use rustc_span::{sym, Span};
 use thin_vec::ThinVec;
 
@@ -68,10 69,10 @@ impl<'a> ParserBuilder<'a> {
  ) -> Result<rustc_parse::parser::Parser<'a>, Option<Vec<Diag<'a>>>> {
  match input {
  Input::File(ref file) => catch_unwind(AssertUnwindSafe(move || {
- new_parser_from_file(psess, file, None)
  unwrap_or_emit_fatal(new_parser_from_file(psess, file, None))
  }))
  .map_err(|_| None),
- Input::Text(text) => rustc_parse::maybe_new_parser_from_source_str(
  Input::Text(text) => rustc_parse::new_parser_from_source_str(
  psess,
  rustc_span::FileName::Custom("stdin".to_owned()),
  text,
@@ -111,7 112,8 @@ impl<'a> Parser<'a> {
  span: Span,
  ) -> Result<(ast::AttrVec, ThinVec<ptr::P<ast::Item>>, Span), ParserError> {
  let result = catch_unwind(AssertUnwindSafe(|| {
- let mut parser = new_parser_from_file(psess.inner(), path, Some(span));
  let mut parser =
  unwrap_or_emit_fatal(new_parser_from_file(psess.inner(), path, Some(span)));
  match parser.parse_mod(&TokenKind::Eof) {
  Ok((a, i, spans)) => Some((a, i, spans.inner_span)),
  Err(e) => {