From 10ecb11ff569e37c588b35861065191ad607b0bb Mon Sep 17 00:00:00 2001 From: Edwin Cheng Date: Tue, 14 May 2019 07:59:28 +0800 Subject: [PATCH] Error out non single root token tree conversion --- crates/ra_mbe/src/syntax_bridge.rs | 46 ++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/crates/ra_mbe/src/syntax_bridge.rs b/crates/ra_mbe/src/syntax_bridge.rs index 73a0780dafe..5e6a6f2a136 100644 --- a/crates/ra_mbe/src/syntax_bridge.rs +++ b/crates/ra_mbe/src/syntax_bridge.rs @@ -50,6 +50,10 @@ pub fn token_tree_to_expr(tt: &tt::Subtree) -> Result, Expand let token_source = SubtreeTokenSource::new(tt); let mut tree_sink = TtTreeSink::new(token_source.querier()); ra_parser::parse_expr(&token_source, &mut tree_sink); + if tree_sink.roots.len() != 1 { + return Err(ExpandError::ConversionError); + } + let syntax = tree_sink.inner.finish(); ast::Expr::cast(&syntax) .map(|m| m.to_owned()) @@ -61,6 +65,10 @@ pub fn token_tree_to_pat(tt: &tt::Subtree) -> Result, ExpandEr let token_source = SubtreeTokenSource::new(tt); let mut tree_sink = TtTreeSink::new(token_source.querier()); ra_parser::parse_pat(&token_source, &mut tree_sink); + if tree_sink.roots.len() != 1 { + return Err(ExpandError::ConversionError); + } + let syntax = tree_sink.inner.finish(); ast::Pat::cast(&syntax).map(|m| m.to_owned()).ok_or_else(|| ExpandError::ConversionError) } @@ -70,6 +78,9 @@ pub fn token_tree_to_ty(tt: &tt::Subtree) -> Result, Expan let token_source = SubtreeTokenSource::new(tt); let mut tree_sink = TtTreeSink::new(token_source.querier()); ra_parser::parse_ty(&token_source, &mut tree_sink); + if tree_sink.roots.len() != 1 { + return Err(ExpandError::ConversionError); + } let syntax = tree_sink.inner.finish(); ast::TypeRef::cast(&syntax).map(|m| m.to_owned()).ok_or_else(|| ExpandError::ConversionError) } @@ -81,6 +92,9 @@ pub fn token_tree_to_macro_stmts( let token_source = SubtreeTokenSource::new(tt); let mut tree_sink = TtTreeSink::new(token_source.querier()); ra_parser::parse_macro_stmts(&token_source, &mut tree_sink); + if tree_sink.roots.len() != 1 { + return Err(ExpandError::ConversionError); + } let syntax = tree_sink.inner.finish(); ast::MacroStmts::cast(&syntax).map(|m| m.to_owned()).ok_or_else(|| ExpandError::ConversionError) } @@ -92,6 +106,9 @@ pub fn token_tree_to_macro_items( let token_source = SubtreeTokenSource::new(tt); let mut tree_sink = TtTreeSink::new(token_source.querier()); ra_parser::parse_macro_items(&token_source, &mut tree_sink); + if tree_sink.roots.len() != 1 { + return Err(ExpandError::ConversionError); + } let syntax = tree_sink.inner.finish(); ast::MacroItems::cast(&syntax).map(|m| m.to_owned()).ok_or_else(|| ExpandError::ConversionError) } @@ -268,6 +285,10 @@ struct TtTreeSink<'a, Q: Querier> { text_pos: TextUnit, token_pos: usize, inner: SyntaxTreeBuilder, + + // Number of roots + // Use for detect ill-form tree which is not single root + roots: smallvec::SmallVec<[usize; 1]>, } impl<'a, Q: Querier> TtTreeSink<'a, Q> { @@ -278,6 +299,7 @@ impl<'a, Q: Querier> TtTreeSink<'a, Q> { text_pos: 0.into(), token_pos: 0, inner: SyntaxTreeBuilder::default(), + roots: smallvec::SmallVec::new(), } } } @@ -323,10 +345,16 @@ impl<'a, Q: Querier> TreeSink for TtTreeSink<'a, Q> { fn start_node(&mut self, kind: SyntaxKind) { self.inner.start_node(kind); + + match self.roots.last_mut() { + None | Some(0) => self.roots.push(1), + Some(ref mut n) => **n += 1, + }; } fn finish_node(&mut self) { self.inner.finish_node(); + *self.roots.last_mut().unwrap() -= 1; } fn error(&mut self, error: ParseError) { @@ -375,4 +403,22 @@ mod tests { assert_eq!(query.token(2 + 15 + 3).1, "\"rust1\""); assert_eq!(query.token(2 + 15 + 3).0, STRING); } + + #[test] + fn stmts_token_trees_to_expr_is_err() { + let rules = create_rules( + r#" + macro_rules! stmts { + () => { + let a = 0; + let b = 0; + let c = 0; + let d = 0; + } + } + "#, + ); + let expansion = expand(&rules, "stmts!()"); + assert!(token_tree_to_expr(&expansion).is_err()); + } }