From 910532ea4559684e16d4acbd058c643599fe9536 Mon Sep 17 00:00:00 2001 From: Austin Bonander Date: Thu, 20 Apr 2017 16:13:13 -0700 Subject: Don't panic if an attribute macro fails to resolve at crate root Adds temporary regression test; this ideally should work as-is (#41430) Closes #41211 --- src/libsyntax/ext/expand.rs | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'src/libsyntax') diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs index 680bd7599ac..842398ea02b 100644 --- a/src/libsyntax/ext/expand.rs +++ b/src/libsyntax/ext/expand.rs @@ -205,6 +205,8 @@ impl<'a, 'b> MacroExpander<'a, 'b> { module.directory.pop(); self.cx.current_expansion.module = Rc::new(module); + let orig_mod_span = krate.module.inner; + let krate_item = Expansion::Items(SmallVector::one(P(ast::Item { attrs: krate.attrs, span: krate.span, @@ -214,11 +216,19 @@ impl<'a, 'b> MacroExpander<'a, 'b> { vis: ast::Visibility::Public, }))); - match self.expand(krate_item).make_items().pop().unwrap().unwrap() { - ast::Item { attrs, node: ast::ItemKind::Mod(module), .. } => { + match self.expand(krate_item).make_items().pop().map(P::unwrap) { + Some(ast::Item { attrs, node: ast::ItemKind::Mod(module), .. }) => { krate.attrs = attrs; krate.module = module; }, + None => { + // Resolution failed so we return an empty expansion + krate.attrs = vec![]; + krate.module = ast::Mod { + inner: orig_mod_span, + items: vec![], + }; + }, _ => unreachable!(), }; -- cgit 1.4.1-3-g733a5