1 files changed, 85 insertions, 45 deletions
diff --git a/crates/mbe/src/lib.rs b/crates/mbe/src/lib.rs
index 19543d777..f3d2da55a 100644
--- a/crates/mbe/src/lib.rs
+++ b/crates/mbe/src/lib.rs
@@ -4,7 +4,7 @@
 //! `TokenTree`s as well!
 mod parser;
-mod mbe_expander;
+mod expander;
 mod syntax_bridge;
 mod tt_iter;
 mod subtree_source;
@@ -12,18 +12,24 @@ mod subtree_source;
 #[cfg(test)]
 mod tests;
+#[cfg(test)]
+mod benchmark;
 use std::fmt;
+use test_utils::mark;
 pub use tt::{Delimiter, DelimiterKind, Punct};
 use crate::{
-    parser::{parse_pattern, parse_template, Op},
+    parser::{parse_pattern, parse_template, MetaTemplate, Op},
    tt_iter::TtIter,
 };
 #[derive(Debug, PartialEq, Eq)]
 pub enum ParseError {
+    UnexpectedToken(String),
    Expected(String),
+    InvalidRepeat,
    RepetitionEmptyTokenTree,
 }
@@ -33,7 +39,6 @@ pub enum ExpandError {
    UnexpectedToken,
    BindingError(String),
    ConversionError,
-    InvalidRepeat,
    ProcMacroError(tt::ExpansionError),
    UnresolvedProcMacro,
    Other(String),
@@ -52,7 +57,6 @@ impl fmt::Display for ExpandError {
            ExpandError::UnexpectedToken => f.write_str("unexpected token in input"),
            ExpandError::BindingError(e) => f.write_str(e),
            ExpandError::ConversionError => f.write_str("could not convert tokens"),
-            ExpandError::InvalidRepeat => f.write_str("invalid repeat expression"),
            ExpandError::ProcMacroError(e) => e.fmt(f),
            ExpandError::UnresolvedProcMacro => f.write_str("unresolved proc macro"),
            ExpandError::Other(e) => f.write_str(e),
@@ -61,8 +65,8 @@ impl fmt::Display for ExpandError {
 }
 pub use crate::syntax_bridge::{
-    ast_to_token_tree, parse_to_token_tree, syntax_node_to_token_tree, token_tree_to_syntax_node,
+    ast_to_token_tree, parse_exprs_with_sep, parse_to_token_tree, syntax_node_to_token_tree,
-    TokenMap,
+    token_tree_to_syntax_node, TokenMap,
 };
 /// This struct contains AST for a single `macro_rules` definition. What might
@@ -76,26 +80,18 @@ pub struct MacroRules {
    shift: Shift,
 }
+/// For Macro 2.0
 #[derive(Clone, Debug, PartialEq, Eq)]
-struct Rule {
+pub struct MacroDef {
-    lhs: MetaTemplate,
+    rules: Vec<Rule>,
-    rhs: MetaTemplate,
+    /// Highest id of the token we have in TokenMap
+    shift: Shift,
 }
 #[derive(Clone, Debug, PartialEq, Eq)]
-struct MetaTemplate {
+struct Rule {
-    delimiter: Option<Delimiter>,
+    lhs: MetaTemplate,
-    tokens: Vec<Result<Op, ExpandError>>,
+    rhs: MetaTemplate,
-}
-impl<'a> MetaTemplate {
-    fn iter(&self) -> impl Iterator<Item = &Result<Op, ExpandError>> {
-        self.tokens.iter()
-    }
-    fn delimiter_kind(&self) -> Option<DelimiterKind> {
-        self.delimiter.map(|it| it.kind)
-    }
 }
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
@@ -179,7 +175,7 @@ impl MacroRules {
        let mut src = TtIter::new(tt);
        let mut rules = Vec::new();
        while src.len() > 0 {
-            let rule = Rule::parse(&mut src)?;
+            let rule = Rule::parse(&mut src, true)?;
            rules.push(rule);
            if let Err(()) = src.expect_char(';') {
                if src.len() > 0 {
@@ -200,7 +196,58 @@ impl MacroRules {
        // apply shift
        let mut tt = tt.clone();
        self.shift.shift_all(&mut tt);
-        mbe_expander::expand(self, &tt)
+        expander::expand_rules(&self.rules, &tt)
+    }
+    pub fn map_id_down(&self, id: tt::TokenId) -> tt::TokenId {
+        self.shift.shift(id)
+    }
+    pub fn map_id_up(&self, id: tt::TokenId) -> (tt::TokenId, Origin) {
+        match self.shift.unshift(id) {
+            Some(id) => (id, Origin::Call),
+            None => (id, Origin::Def),
+        }
+    }
+}
+impl MacroDef {
+    pub fn parse(tt: &tt::Subtree) -> Result<MacroDef, ParseError> {
+        let mut src = TtIter::new(tt);
+        let mut rules = Vec::new();
+        if Some(tt::DelimiterKind::Brace) == tt.delimiter_kind() {
+            mark::hit!(parse_macro_def_rules);
+            while src.len() > 0 {
+                let rule = Rule::parse(&mut src, true)?;
+                rules.push(rule);
+                if let Err(()) = src.expect_char(';') {
+                    if src.len() > 0 {
+                        return Err(ParseError::Expected("expected `;`".to_string()));
+                    }
+                    break;
+                }
+            }
+        } else {
+            mark::hit!(parse_macro_def_simple);
+            let rule = Rule::parse(&mut src, false)?;
+            if src.len() != 0 {
+                return Err(ParseError::Expected("remain tokens in macro def".to_string()));
+            }
+            rules.push(rule);
+        }
+        for rule in rules.iter() {
+            validate(&rule.lhs)?;
+        }
+        Ok(MacroDef { rules, shift: Shift::new(tt) })
+    }
+    pub fn expand(&self, tt: &tt::Subtree) -> ExpandResult<tt::Subtree> {
+        // apply shift
+        let mut tt = tt.clone();
+        self.shift.shift_all(&mut tt);
+        expander::expand_rules(&self.rules, &tt)
    }
    pub fn map_id_down(&self, id: tt::TokenId) -> tt::TokenId {
@@ -216,57 +263,50 @@ impl MacroRules {
 }
 impl Rule {
-    fn parse(src: &mut TtIter) -> Result<Rule, ParseError> {
+    fn parse(src: &mut TtIter, expect_arrow: bool) -> Result<Rule, ParseError> {
        let lhs = src
            .expect_subtree()
            .map_err(|()| ParseError::Expected("expected subtree".to_string()))?;
-        src.expect_char('=').map_err(|()| ParseError::Expected("expected `=`".to_string()))?;
+        if expect_arrow {
-        src.expect_char('>').map_err(|()| ParseError::Expected("expected `>`".to_string()))?;
+            src.expect_char('=').map_err(|()| ParseError::Expected("expected `=`".to_string()))?;
+            src.expect_char('>').map_err(|()| ParseError::Expected("expected `>`".to_string()))?;
+        }
        let rhs = src
            .expect_subtree()
            .map_err(|()| ParseError::Expected("expected subtree".to_string()))?;
-        let lhs = MetaTemplate { tokens: parse_pattern(&lhs), delimiter: None };
+        let lhs = MetaTemplate(parse_pattern(&lhs)?);
-        let rhs = MetaTemplate { tokens: parse_template(&rhs), delimiter: None };
+        let rhs = MetaTemplate(parse_template(&rhs)?);
        Ok(crate::Rule { lhs, rhs })
    }
 }
-fn to_parse_error(e: &ExpandError) -> ParseError {
-    let msg = match e {
-        ExpandError::InvalidRepeat => "invalid repeat".to_string(),
-        _ => "invalid macro definition".to_string(),
-    };
-    ParseError::Expected(msg)
-}
 fn validate(pattern: &MetaTemplate) -> Result<(), ParseError> {
    for op in pattern.iter() {
-        let op = op.as_ref().map_err(|e| to_parse_error(&e))?;
        match op {
-            Op::Subtree(subtree) => validate(&subtree)?,
+            Op::Subtree { tokens, .. } => validate(&tokens)?,
-            Op::Repeat { subtree, separator, .. } => {
+            Op::Repeat { tokens: subtree, separator, .. } => {
                // Checks that no repetition which could match an empty token
                // https://github.com/rust-lang/rust/blob/a58b1ed44f5e06976de2bdc4d7dc81c36a96934f/src/librustc_expand/mbe/macro_rules.rs#L558
                if separator.is_none() {
                    if subtree.iter().all(|child_op| {
-                        match child_op.as_ref().map_err(to_parse_error) {
+                        match child_op {
-                            Ok(Op::Var { kind, .. }) => {
+                            Op::Var { kind, .. } => {
                                // vis is optional
                                if kind.as_ref().map_or(false, |it| it == "vis") {
                                    return true;
                                }
                            }
-                            Ok(Op::Repeat { kind, .. }) => {
+                            Op::Repeat { kind, .. } => {
                                return matches!(
                                    kind,
                                    parser::RepeatKind::ZeroOrMore | parser::RepeatKind::ZeroOrOne
                                )
                            }
-                            _ => {}
+                            Op::Leaf(_) => {}
+                            Op::Subtree { .. } => {}
                        }
                        false
                    }) {