Add expr, pat, ty and macro_stmts

1 files changed, 41 insertions, 5 deletions

diff --git a/crates/ra_mbe/src/syntax_bridge.rs b/crates/ra_mbe/src/syntax_bridge.rs
index 19e09be80..6af3b1995 100644
--- a/crates/ra_mbe/src/syntax_bridge.rs
+++ b/crates/ra_mbe/src/syntax_bridge.rs
@@ -32,11 +32,11 @@ pub fn syntax_node_to_token_tree(node: &SyntaxNode) -> Option<(tt::Subtree, Toke
 
 // The following items are what `rustc` macro can be parsed into :
 // link: https://github.com/rust-lang/rust/blob/9ebf47851a357faa4cd97f4b1dc7835f6376e639/src/libsyntax/ext/expand.rs#L141
-// * Expr(P<ast::Expr>)
-// * Pat(P<ast::Pat>)
-// * Ty(P<ast::Ty>)
-// * Stmts(SmallVec<[ast::Stmt; 1]>)
-// * Items(SmallVec<[P<ast::Item>; 1]>)
+// * Expr(P<ast::Expr>)                     -> token_tree_to_expr
+// * Pat(P<ast::Pat>)                       -> token_tree_to_pat
+// * Ty(P<ast::Ty>)                         -> token_tree_to_ty
+// * Stmts(SmallVec<[ast::Stmt; 1]>)        -> token_tree_to_stmts
+// * Items(SmallVec<[P<ast::Item>; 1]>)     -> token_tree_to_items
 //
 // * TraitItems(SmallVec<[ast::TraitItem; 1]>)
 // * ImplItems(SmallVec<[ast::ImplItem; 1]>)
@@ -44,6 +44,42 @@ pub fn syntax_node_to_token_tree(node: &SyntaxNode) -> Option<(tt::Subtree, Toke
 //
 //
 
+/// Parses the token tree (result of macro expansion) to an expression
+pub fn token_tree_to_expr(tt: &tt::Subtree) -> TreeArc<ast::Expr> {
+    let token_source = SubtreeTokenSource::new(tt);
+    let mut tree_sink = TtTreeSink::new(token_source.querier());
+    ra_parser::parse_expr(&token_source, &mut tree_sink);
+    let syntax = tree_sink.inner.finish();
+    ast::Expr::cast(&syntax).unwrap().to_owned()
+}
+
+/// Parses the token tree (result of macro expansion) to a Pattern
+pub fn token_tree_to_pat(tt: &tt::Subtree) -> TreeArc<ast::Pat> {
+    let token_source = SubtreeTokenSource::new(tt);
+    let mut tree_sink = TtTreeSink::new(token_source.querier());
+    ra_parser::parse_pat(&token_source, &mut tree_sink);
+    let syntax = tree_sink.inner.finish();
+    ast::Pat::cast(&syntax).unwrap().to_owned()
+}
+
+/// Parses the token tree (result of macro expansion) to a Type
+pub fn token_tree_to_ty(tt: &tt::Subtree) -> TreeArc<ast::TypeRef> {
+    let token_source = SubtreeTokenSource::new(tt);
+    let mut tree_sink = TtTreeSink::new(token_source.querier());
+    ra_parser::parse_ty(&token_source, &mut tree_sink);
+    let syntax = tree_sink.inner.finish();
+    ast::TypeRef::cast(&syntax).unwrap().to_owned()
+}
+
+/// Parses the token tree (result of macro expansion) as a sequence of stmts
+pub fn token_tree_to_macro_stmts(tt: &tt::Subtree) -> TreeArc<ast::MacroStmts> {
+    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);
+    let syntax = tree_sink.inner.finish();
+    ast::MacroStmts::cast(&syntax).unwrap().to_owned()
+}
+
 /// Parses the token tree (result of macro expansion) as a sequence of items
 pub fn token_tree_to_macro_items(tt: &tt::Subtree) -> TreeArc<ast::MacroItems> {
     let token_source = SubtreeTokenSource::new(tt);