Merge #1168

1168: Add all remaining mbe matchers r=matklad a=edwin0cheng

This PR adds following  mbe matchers:

* block
* meta
* tt
* literal
* vis

Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>

crates/ra_mbe/src/lib.rs

@@ -731,4 +731,95 @@ 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 ;}");
+    }
+
+    #[test]
+    fn test_meta() {
+        let rules = create_rules(
+            r#"
+        macro_rules! foo {
+            ($ i:meta) => (
+                #[$ i]
+                fn bar() {}
+            )
+        }
+"#,
+        );
+        assert_expansion(
+            &rules,
+            r#"foo! { cfg(target_os = "windows") }"#,
+            r#"# [cfg (target_os = "windows")] fn bar () {}"#,
+        );
+    }
+
+    #[test]
+    fn test_tt_block() {
+        let rules = create_rules(
+            r#"
+        macro_rules! foo {
+            ($ i:tt) => { fn foo() $ i }
+        }
+"#,
+        );
+        assert_expansion(&rules, r#"foo! { { 1; } }"#, r#"fn foo () {1 ;}"#);
+    }
+
+    #[test]
+    fn test_tt_group() {
+        let rules = create_rules(
+            r#"
+        macro_rules! foo {
+             ($($ i:tt)*) => { $($ i)* }
+        }
+"#,
+        );
+        assert_expansion(&rules, r#"foo! { fn foo() {} }"#, r#"fn foo () {}"#);
+    }
+
+    #[test]
+    fn test_lifetime() {
+        let rules = create_rules(
+            r#"
+        macro_rules! foo {
+              ($ lt:lifetime) => { struct Ref<$ lt>{ s: &$ lt str } }
+        }
+"#,
+        );
+        assert_expansion(&rules, r#"foo!{'a}"#, r#"struct Ref < 'a > {s : & 'a str}"#);
+    }
+
+    #[test]
+    fn test_literal() {
+        let rules = create_rules(
+            r#"
+        macro_rules! foo {
+              ($ type:ty $ lit:literal) => { const VALUE: $ type = $ lit;};
+        }
+"#,
+        );
+        assert_expansion(&rules, r#"foo!(u8 0)"#, r#"const VALUE : u8 = 0 ;"#);
+    }
+
+    #[test]
+    fn test_vis() {
+        let rules = create_rules(
+            r#"
+        macro_rules! foo {
+              ($ vis:vis $ name:ident) => { $ vis fn $ name() {}};
+        }
+"#,
+        );
+        assert_expansion(&rules, r#"foo!(pub foo);"#, r#"pub fn foo () {}"#);
+    }
 }

crates/ra_mbe/src/mbe_expander.rs

@@ -161,11 +161,43 @@ 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()));
+                        }
+                        "meta" => {
+                            let meta =
+                                input.eat_meta().ok_or(ExpandError::UnexpectedToken)?.clone();
+                            res.inner.insert(text.clone(), Binding::Simple(meta.into()));
+                        }
+                        "tt" => {
+                            let token = input.eat().ok_or(ExpandError::UnexpectedToken)?.clone();
+                            res.inner.insert(text.clone(), Binding::Simple(token.into()));
+                        }
                         "item" => {
                             let item =
                                 input.eat_item().ok_or(ExpandError::UnexpectedToken)?.clone();
                             res.inner.insert(text.clone(), Binding::Simple(item.into()));
                         }
+                        "lifetime" => {
+                            let lifetime =
+                                input.eat_lifetime().ok_or(ExpandError::UnexpectedToken)?.clone();
+                            res.inner.insert(text.clone(), Binding::Simple(lifetime.into()));
+                        }
+                        "literal" => {
+                            let literal =
+                                input.eat_literal().ok_or(ExpandError::UnexpectedToken)?.clone();
+                            res.inner.insert(
+                                text.clone(),
+                                Binding::Simple(tt::Leaf::from(literal).into()),
+                            );
+                        }
+                        "vis" => {
+                            let vis = input.eat_vis().ok_or(ExpandError::UnexpectedToken)?.clone();
+                            res.inner.insert(text.clone(), Binding::Simple(vis.into()));
+                        }
+
                         _ => return Err(ExpandError::UnexpectedToken),
                     }
                 }

crates/ra_mbe/src/subtree_parser.rs

@@ -46,10 +46,22 @@ 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_meta(self) -> Option<tt::TokenTree> {
+        self.parse(ra_parser::parse_meta)
+    }
+
     pub fn parse_item(self) -> Option<tt::TokenTree> {
         self.parse(ra_parser::parse_item)
     }
 
+    pub fn parse_vis(self) -> Option<tt::TokenTree> {
+        self.parse(ra_parser::parse_vis)
+    }
+
     fn parse<F>(self, f: F) -> Option<tt::TokenTree>
     where
         F: FnOnce(&dyn TokenSource, &mut dyn TreeSink),

crates/ra_mbe/src/syntax_bridge.rs

@@ -157,7 +157,10 @@ fn convert_tt(
                         );
                     }
                 } else {
-                    let child = if token.kind().is_keyword() || token.kind() == IDENT {
+                    let child: tt::TokenTree = if token.kind().is_keyword()
+                        || token.kind() == IDENT
+                        || token.kind() == LIFETIME
+                    {
                         let relative_range = token.range() - global_offset;
                         let id = token_map.alloc(relative_range);
                         let text = token.text().clone();

crates/ra_mbe/src/tt_cursor.rs

@@ -41,6 +41,13 @@ impl<'a> TtCursor<'a> {
         }
     }
 
+    pub(crate) fn at_literal(&mut self) -> Option<&'a tt::Literal> {
+        match self.current() {
+            Some(tt::TokenTree::Leaf(tt::Leaf::Literal(i))) => Some(i),
+            _ => None,
+        }
+    }
+
     pub(crate) fn bump(&mut self) {
         self.pos += 1;
     }
@@ -79,6 +86,13 @@ impl<'a> TtCursor<'a> {
         })
     }
 
+    pub(crate) fn eat_literal(&mut self) -> Option<&'a tt::Literal> {
+        self.at_literal().map(|i| {
+            self.bump();
+            i
+        })
+    }
+
     pub(crate) fn eat_path(&mut self) -> Option<tt::TokenTree> {
         let parser = Parser::new(&mut self.pos, self.subtree);
         parser.parse_path()
@@ -104,11 +118,37 @@ 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_meta(&mut self) -> Option<tt::TokenTree> {
+        let parser = Parser::new(&mut self.pos, self.subtree);
+        parser.parse_meta()
+    }
+
     pub(crate) fn eat_item(&mut self) -> Option<tt::TokenTree> {
         let parser = Parser::new(&mut self.pos, self.subtree);
         parser.parse_item()
     }
 
+    pub(crate) fn eat_lifetime(&mut self) -> Option<tt::TokenTree> {
+        // check if it start from "`"
+        if let Some(ident) = self.at_ident() {
+            if ident.text.chars().next()? != '\'' {
+                return None;
+            }
+        }
+
+        self.eat_ident().cloned().map(|ident| tt::Leaf::from(ident).into())
+    }
+
+    pub(crate) fn eat_vis(&mut self) -> Option<tt::TokenTree> {
+        let parser = Parser::new(&mut self.pos, self.subtree);
+        parser.parse_vis()
+    }
+
     pub(crate) fn expect_char(&mut self, char: char) -> Result<(), ParseError> {
         if self.at_char(char) {
             self.bump();

crates/ra_parser/src/grammar.rs

@@ -95,6 +95,37 @@ 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);
+}
+
+// Parse a meta item , which excluded [], e.g : #[ MetaItem ]
+pub(crate) fn meta_item(p: &mut Parser) {
+    fn is_delimiter(p: &mut Parser) -> bool {
+        match p.current() {
+            L_CURLY | L_PAREN | L_BRACK => true,
+            _ => false,
+        }
+    }
+
+    if is_delimiter(p) {
+        items::token_tree(p);
+        return;
+    }
+
+    let m = p.start();
+    while !p.at(EOF) {
+        if is_delimiter(p) {
+            items::token_tree(p);
+            break;
+        } else {
+            p.bump();
+        }
+    }
+
+    m.complete(p, TOKEN_TREE);
+}
+
 pub(crate) fn item(p: &mut Parser) {
     items::item_or_macro(p, true, items::ItemFlavor::Mod)
 }
@@ -136,7 +167,7 @@ impl BlockLike {
     }
 }
 
-fn opt_visibility(p: &mut Parser) -> bool {
+pub(crate) fn opt_visibility(p: &mut Parser) -> bool {
     match p.current() {
         PUB_KW => {
             let m = p.start();

crates/ra_parser/src/lib.rs

@@ -93,11 +93,27 @@ 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);
+}
+
+pub fn parse_meta(token_source: &dyn TokenSource, tree_sink: &mut dyn TreeSink) {
+    parse_from_tokens(token_source, tree_sink, grammar::meta_item);
+}
+
 /// 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);
 }
 
+/// Parse given tokens into the given sink as an visibility qualifier
+pub fn parse_vis(token_source: &dyn TokenSource, tree_sink: &mut dyn TreeSink) {
+    parse_from_tokens(token_source, tree_sink, |p| {
+        grammar::opt_visibility(p);
+    });
+}
+
 pub fn parse_macro_items(token_source: &dyn TokenSource, tree_sink: &mut dyn TreeSink) {
     parse_from_tokens(token_source, tree_sink, grammar::macro_items);
 }