Add block matcher

crates/ra_mbe/src/lib.rs

@@ -731,4 +731,16 @@ MACRO_ITEMS@[0; 40)
         }
 "#, r#"extern crate a ; mod b ; mod c {} use d ; const E : i32 = 0 ; static F : i32 = 0 ; impl G {} struct H ; enum I {Foo} trait J {} fn h () {} extern {} type T = u8 ;"#);
     }
+
+    #[test]
+    fn test_block() {
+        let rules = create_rules(
+            r#"
+        macro_rules! foo {
+            ($ i:block) => { fn foo() $ i }
+        }
+"#,
+        );
+        assert_expansion(&rules, "foo! { { 1; } }", "fn foo () {1 ;}");
+    }
 }

crates/ra_mbe/src/mbe_expander.rs

@@ -161,6 +161,11 @@ fn match_lhs(pattern: &crate::Subtree, input: &mut TtCursor) -> Result<Bindings,
                             let pat = input.eat_stmt().ok_or(ExpandError::UnexpectedToken)?.clone();
                             res.inner.insert(text.clone(), Binding::Simple(pat.into()));
                         }
+                        "block" => {
+                            let block =
+                                input.eat_block().ok_or(ExpandError::UnexpectedToken)?.clone();
+                            res.inner.insert(text.clone(), Binding::Simple(block.into()));
+                        }
                         "item" => {
                             let item =
                                 input.eat_item().ok_or(ExpandError::UnexpectedToken)?.clone();

crates/ra_mbe/src/subtree_parser.rs

@@ -46,6 +46,10 @@ impl<'a> Parser<'a> {
         self.parse(|src, sink| ra_parser::parse_stmt(src, sink, false))
     }
 
+    pub fn parse_block(self) -> Option<tt::TokenTree> {
+        self.parse(ra_parser::parse_block)
+    }
+
     pub fn parse_item(self) -> Option<tt::TokenTree> {
         self.parse(ra_parser::parse_item)
     }

crates/ra_mbe/src/tt_cursor.rs

@@ -104,6 +104,11 @@ impl<'a> TtCursor<'a> {
         parser.parse_stmt()
     }
 
+    pub(crate) fn eat_block(&mut self) -> Option<tt::TokenTree> {
+        let parser = Parser::new(&mut self.pos, self.subtree);
+        parser.parse_block()
+    }
+
     pub(crate) fn eat_item(&mut self) -> Option<tt::TokenTree> {
         let parser = Parser::new(&mut self.pos, self.subtree);
         parser.parse_item()

crates/ra_parser/src/grammar.rs

@@ -95,6 +95,10 @@ pub(crate) fn stmt(p: &mut Parser, with_semi: bool) {
     expressions::stmt(p, with_semi)
 }
 
+pub(crate) fn block(p: &mut Parser) {
+    expressions::block(p);
+}
+
 pub(crate) fn item(p: &mut Parser) {
     items::item_or_macro(p, true, items::ItemFlavor::Mod)
 }

crates/ra_parser/src/lib.rs

@@ -93,6 +93,11 @@ pub fn parse_stmt(token_source: &dyn TokenSource, tree_sink: &mut dyn TreeSink,
     parse_from_tokens(token_source, tree_sink, |p| grammar::stmt(p, with_semi));
 }
 
+/// Parse given tokens into the given sink as a block
+pub fn parse_block(token_source: &dyn TokenSource, tree_sink: &mut dyn TreeSink) {
+    parse_from_tokens(token_source, tree_sink, grammar::block);
+}
+
 /// Parse given tokens into the given sink as an item
 pub fn parse_item(token_source: &dyn TokenSource, tree_sink: &mut dyn TreeSink) {
     parse_from_tokens(token_source, tree_sink, grammar::item);