Handle fatal errors when parsing doctests

This commit is contained in:
Eduardo Broto 2020-12-15 23:18:03 +01:00
parent 6c83e5684d
commit 39bcf8e554
3 changed files with 66 additions and 53 deletions

View File

@ -451,66 +451,72 @@ fn check_doc<'a, Events: Iterator<Item = (pulldown_cmark::Event<'a>, Range<usize
}
fn check_code(cx: &LateContext<'_>, text: &str, span: Span) {
fn has_needless_main(code: &str) -> bool {
let filename = FileName::anon_source_code(code);
fn has_needless_main(cx: &LateContext<'_>, code: &str) -> bool {
rustc_driver::catch_fatal_errors(|| {
rustc_span::with_session_globals(cx.tcx.sess.edition(), || {
let filename = FileName::anon_source_code(code);
let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
let emitter = EmitterWriter::new(box io::sink(), None, false, false, false, None, false);
let handler = Handler::with_emitter(false, None, box emitter);
let sess = ParseSess::with_span_handler(handler, sm);
let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
let emitter = EmitterWriter::new(box io::sink(), None, false, false, false, None, false);
let handler = Handler::with_emitter(false, None, box emitter);
let sess = ParseSess::with_span_handler(handler, sm);
let mut parser = match maybe_new_parser_from_source_str(&sess, filename, code.into()) {
Ok(p) => p,
Err(errs) => {
for mut err in errs {
err.cancel();
}
return false;
},
};
let mut relevant_main_found = false;
loop {
match parser.parse_item() {
Ok(Some(item)) => match &item.kind {
// Tests with one of these items are ignored
ItemKind::Static(..)
| ItemKind::Const(..)
| ItemKind::ExternCrate(..)
| ItemKind::ForeignMod(..) => return false,
// We found a main function ...
ItemKind::Fn(_, sig, _, Some(block)) if item.ident.name == sym::main => {
let is_async = matches!(sig.header.asyncness, Async::Yes { .. });
let returns_nothing = match &sig.decl.output {
FnRetTy::Default(..) => true,
FnRetTy::Ty(ty) if ty.kind.is_unit() => true,
_ => false,
};
if returns_nothing && !is_async && !block.stmts.is_empty() {
// This main function should be linted, but only if there are no other functions
relevant_main_found = true;
} else {
// This main function should not be linted, we're done
return false;
let mut parser = match maybe_new_parser_from_source_str(&sess, filename, code.into()) {
Ok(p) => p,
Err(errs) => {
for mut err in errs {
err.cancel();
}
return false;
},
// Another function was found; this case is ignored too
ItemKind::Fn(..) => return false,
_ => {},
},
Ok(None) => break,
Err(mut e) => {
e.cancel();
return false;
},
}
}
};
relevant_main_found
let mut relevant_main_found = false;
loop {
match parser.parse_item() {
Ok(Some(item)) => match &item.kind {
// Tests with one of these items are ignored
ItemKind::Static(..)
| ItemKind::Const(..)
| ItemKind::ExternCrate(..)
| ItemKind::ForeignMod(..) => return false,
// We found a main function ...
ItemKind::Fn(_, sig, _, Some(block)) if item.ident.name == sym::main => {
let is_async = matches!(sig.header.asyncness, Async::Yes { .. });
let returns_nothing = match &sig.decl.output {
FnRetTy::Default(..) => true,
FnRetTy::Ty(ty) if ty.kind.is_unit() => true,
_ => false,
};
if returns_nothing && !is_async && !block.stmts.is_empty() {
// This main function should be linted, but only if there are no other functions
relevant_main_found = true;
} else {
// This main function should not be linted, we're done
return false;
}
},
// Another function was found; this case is ignored too
ItemKind::Fn(..) => return false,
_ => {},
},
Ok(None) => break,
Err(mut e) => {
e.cancel();
return false;
},
}
}
relevant_main_found
})
})
.ok()
.unwrap_or_default()
}
if has_needless_main(text) {
if has_needless_main(cx, text) {
span_lint(cx, NEEDLESS_DOCTEST_MAIN, span, "needless `fn main` in doctest");
}
}

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@ -27,6 +27,7 @@ extern crate rustc_ast;
extern crate rustc_ast_pretty;
extern crate rustc_attr;
extern crate rustc_data_structures;
extern crate rustc_driver;
extern crate rustc_errors;
extern crate rustc_hir;
extern crate rustc_hir_pretty;

View File

@ -128,6 +128,12 @@ fn bad_doctests() {}
/// ```
fn no_false_positives() {}
/// Yields a parse error when interpreted as rust code:
/// ```
/// r#"hi"
/// ```
fn issue_6022() {}
fn main() {
bad_doctests();
no_false_positives();