Merge #10514

10514: internal: clean up code duplication r=matklad a=matklad

bors r+
🤖

Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>

5 files changed, 45 insertions, 77 deletions

diff --git a/crates/hir_expand/src/db.rs b/crates/hir_expand/src/db.rs
index c87fb6a17d2..63b5022ae83 100644
--- a/crates/hir_expand/src/db.rs
+++ b/crates/hir_expand/src/db.rs
@@ -28,10 +28,8 @@ static TOKEN_LIMIT: Limit = Limit::new(524_288);
 
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub enum TokenExpander {
-    /// Old-style `macro_rules`.
-    MacroRules { mac: mbe::MacroRules, def_site_token_map: mbe::TokenMap },
-    /// AKA macros 2.0.
-    MacroDef { mac: mbe::MacroDef, def_site_token_map: mbe::TokenMap },
+    /// Old-style `macro_rules` or the new macros 2.0
+    DeclarativeMacro { mac: mbe::DeclarativeMacro, def_site_token_map: mbe::TokenMap },
     /// Stuff like `line!` and `file!`.
     Builtin(BuiltinFnLikeExpander),
     /// `global_allocator` and such.
@@ -50,8 +48,7 @@ impl TokenExpander {
         tt: &tt::Subtree,
     ) -> mbe::ExpandResult<tt::Subtree> {
         match self {
-            TokenExpander::MacroRules { mac, .. } => mac.expand(tt),
-            TokenExpander::MacroDef { mac, .. } => mac.expand(tt),
+            TokenExpander::DeclarativeMacro { mac, .. } => mac.expand(tt),
             TokenExpander::Builtin(it) => it.expand(db, id, tt),
             TokenExpander::BuiltinAttr(it) => it.expand(db, id, tt),
             TokenExpander::BuiltinDerive(it) => it.expand(db, id, tt),
@@ -66,8 +63,7 @@ impl TokenExpander {
 
     pub(crate) fn map_id_down(&self, id: tt::TokenId) -> tt::TokenId {
         match self {
-            TokenExpander::MacroRules { mac, .. } => mac.map_id_down(id),
-            TokenExpander::MacroDef { mac, .. } => mac.map_id_down(id),
+            TokenExpander::DeclarativeMacro { mac, .. } => mac.map_id_down(id),
             TokenExpander::Builtin(..)
             | TokenExpander::BuiltinAttr(..)
             | TokenExpander::BuiltinDerive(..)
@@ -77,8 +73,7 @@ impl TokenExpander {
 
     pub(crate) fn map_id_up(&self, id: tt::TokenId) -> (tt::TokenId, mbe::Origin) {
         match self {
-            TokenExpander::MacroRules { mac, .. } => mac.map_id_up(id),
-            TokenExpander::MacroDef { mac, .. } => mac.map_id_up(id),
+            TokenExpander::DeclarativeMacro { mac, .. } => mac.map_id_up(id),
             TokenExpander::Builtin(..)
             | TokenExpander::BuiltinAttr(..)
             | TokenExpander::BuiltinDerive(..)
@@ -368,24 +363,27 @@ fn macro_arg_text(db: &dyn AstDatabase, id: MacroCallId) -> Option<GreenNode> {
 
 fn macro_def(db: &dyn AstDatabase, id: MacroDefId) -> Result<Arc<TokenExpander>, mbe::ParseError> {
     match id.kind {
-        MacroDefKind::Declarative(ast_id) => match ast_id.to_node(db) {
-            ast::Macro::MacroRules(macro_rules) => {
-                let arg = macro_rules
-                    .token_tree()
-                    .ok_or_else(|| mbe::ParseError::Expected("expected a token tree".into()))?;
-                let (tt, def_site_token_map) = mbe::syntax_node_to_token_tree(arg.syntax());
-                let mac = mbe::MacroRules::parse(&tt)?;
-                Ok(Arc::new(TokenExpander::MacroRules { mac, def_site_token_map }))
-            }
-            ast::Macro::MacroDef(macro_def) => {
-                let arg = macro_def
-                    .body()
-                    .ok_or_else(|| mbe::ParseError::Expected("expected a token tree".into()))?;
-                let (tt, def_site_token_map) = mbe::syntax_node_to_token_tree(arg.syntax());
-                let mac = mbe::MacroDef::parse(&tt)?;
-                Ok(Arc::new(TokenExpander::MacroDef { mac, def_site_token_map }))
-            }
-        },
+        MacroDefKind::Declarative(ast_id) => {
+            let (mac, def_site_token_map) = match ast_id.to_node(db) {
+                ast::Macro::MacroRules(macro_rules) => {
+                    let arg = macro_rules
+                        .token_tree()
+                        .ok_or_else(|| mbe::ParseError::Expected("expected a token tree".into()))?;
+                    let (tt, def_site_token_map) = mbe::syntax_node_to_token_tree(arg.syntax());
+                    let mac = mbe::DeclarativeMacro::parse_macro_rules(&tt)?;
+                    (mac, def_site_token_map)
+                }
+                ast::Macro::MacroDef(macro_def) => {
+                    let arg = macro_def
+                        .body()
+                        .ok_or_else(|| mbe::ParseError::Expected("expected a token tree".into()))?;
+                    let (tt, def_site_token_map) = mbe::syntax_node_to_token_tree(arg.syntax());
+                    let mac = mbe::DeclarativeMacro::parse_macro2(&tt)?;
+                    (mac, def_site_token_map)
+                }
+            };
+            Ok(Arc::new(TokenExpander::DeclarativeMacro { mac, def_site_token_map }))
+        }
         MacroDefKind::BuiltIn(expander, _) => Ok(Arc::new(TokenExpander::Builtin(expander))),
         MacroDefKind::BuiltInAttr(expander, _) => {
             Ok(Arc::new(TokenExpander::BuiltinAttr(expander)))
diff --git a/crates/hir_expand/src/hygiene.rs b/crates/hir_expand/src/hygiene.rs
index b2879e37c35..51f14d684c1 100644
--- a/crates/hir_expand/src/hygiene.rs
+++ b/crates/hir_expand/src/hygiene.rs
@@ -160,11 +160,9 @@ impl HygieneInfo {
                     InFile::new(loc.kind.file_id(), loc.kind.arg(db)?.text_range().start()),
                 ),
                 mbe::Origin::Def => match (&*self.macro_def, &self.attr_input_or_mac_def_start) {
-                    (
-                        TokenExpander::MacroDef { def_site_token_map, .. }
-                        | TokenExpander::MacroRules { def_site_token_map, .. },
-                        Some(tt),
-                    ) => (def_site_token_map, *tt),
+                    (TokenExpander::DeclarativeMacro { def_site_token_map, .. }, Some(tt)) => {
+                        (def_site_token_map, *tt)
+                    }
                     _ => panic!("`Origin::Def` used with non-`macro_rules!` macro"),
                 },
             },
diff --git a/crates/hir_expand/src/lib.rs b/crates/hir_expand/src/lib.rs
index f227c7a7dd8..ee9a65b2669 100644
--- a/crates/hir_expand/src/lib.rs
+++ b/crates/hir_expand/src/lib.rs
@@ -465,11 +465,9 @@ impl ExpansionInfo {
             _ => match origin {
                 mbe::Origin::Call => (&self.macro_arg.1, self.arg.clone()),
                 mbe::Origin::Def => match (&*self.macro_def, &self.attr_input_or_mac_def) {
-                    (
-                        TokenExpander::MacroRules { def_site_token_map, .. }
-                        | TokenExpander::MacroDef { def_site_token_map, .. },
-                        Some(tt),
-                    ) => (def_site_token_map, tt.syntax().cloned()),
+                    (TokenExpander::DeclarativeMacro { def_site_token_map, .. }, Some(tt)) => {
+                        (def_site_token_map, tt.syntax().cloned())
+                    }
                     _ => panic!("`Origin::Def` used with non-`macro_rules!` macro"),
                 },
             },
diff --git a/crates/mbe/src/benchmark.rs b/crates/mbe/src/benchmark.rs
index cd5d76be3c0..a10f0e834df 100644
--- a/crates/mbe/src/benchmark.rs
+++ b/crates/mbe/src/benchmark.rs
@@ -9,7 +9,7 @@ use test_utils::{bench, bench_fixture, skip_slow_tests};
 
 use crate::{
     parser::{Op, RepeatKind, Separator},
-    syntax_node_to_token_tree, MacroRules,
+    syntax_node_to_token_tree, DeclarativeMacro,
 };
 
 #[test]
@@ -20,7 +20,7 @@ fn benchmark_parse_macro_rules() {
     let rules = macro_rules_fixtures_tt();
     let hash: usize = {
         let _pt = bench("mbe parse macro rules");
-        rules.values().map(|it| MacroRules::parse(it).unwrap().rules.len()).sum()
+        rules.values().map(|it| DeclarativeMacro::parse_macro_rules(it).unwrap().rules.len()).sum()
     };
     assert_eq!(hash, 1144);
 }
@@ -47,10 +47,10 @@ fn benchmark_expand_macro_rules() {
     assert_eq!(hash, 69413);
 }
 
-fn macro_rules_fixtures() -> FxHashMap<String, MacroRules> {
+fn macro_rules_fixtures() -> FxHashMap<String, DeclarativeMacro> {
     macro_rules_fixtures_tt()
         .into_iter()
-        .map(|(id, tt)| (id, MacroRules::parse(&tt).unwrap()))
+        .map(|(id, tt)| (id, DeclarativeMacro::parse_macro_rules(&tt).unwrap()))
         .collect()
 }
 
@@ -71,7 +71,7 @@ fn macro_rules_fixtures_tt() -> FxHashMap<String, tt::Subtree> {
 }
 
 /// Generate random invocation fixtures from rules
-fn invocation_fixtures(rules: &FxHashMap<String, MacroRules>) -> Vec<(String, tt::Subtree)> {
+fn invocation_fixtures(rules: &FxHashMap<String, DeclarativeMacro>) -> Vec<(String, tt::Subtree)> {
     let mut seed = 123456789;
     let mut res = Vec::new();
 
diff --git a/crates/mbe/src/lib.rs b/crates/mbe/src/lib.rs
index 6cd084eaeab..498a1b3323c 100644
--- a/crates/mbe/src/lib.rs
+++ b/crates/mbe/src/lib.rs
@@ -83,15 +83,7 @@ pub use crate::{
 /// `tt::TokenTree`, but there's a crucial difference: in macro rules, `$ident`
 /// and `$()*` have special meaning (see `Var` and `Repeat` data structures)
 #[derive(Clone, Debug, PartialEq, Eq)]
-pub struct MacroRules {
-    rules: Vec<Rule>,
-    /// Highest id of the token we have in TokenMap
-    shift: Shift,
-}
-
-/// For Macro 2.0
-#[derive(Clone, Debug, PartialEq, Eq)]
-pub struct MacroDef {
+pub struct DeclarativeMacro {
     rules: Vec<Rule>,
     /// Highest id of the token we have in TokenMap
     shift: Shift,
@@ -176,8 +168,9 @@ pub enum Origin {
     Call,
 }
 
-impl MacroRules {
-    pub fn parse(tt: &tt::Subtree) -> Result<MacroRules, ParseError> {
+impl DeclarativeMacro {
+    /// The old, `macro_rules! m {}` flavor.
+    pub fn parse_macro_rules(tt: &tt::Subtree) -> Result<DeclarativeMacro, ParseError> {
         // Note: this parsing can be implemented using mbe machinery itself, by
         // matching against `$($lhs:tt => $rhs:tt);*` pattern, but implementing
         // manually seems easier.
@@ -198,30 +191,11 @@ impl MacroRules {
             validate(&rule.lhs)?;
         }
 
-        Ok(MacroRules { 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)
+        Ok(DeclarativeMacro { rules, shift: Shift::new(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> {
+    /// The new, unstable `macro m {}` flavor.
+    pub fn parse_macro2(tt: &tt::Subtree) -> Result<DeclarativeMacro, ParseError> {
         let mut src = TtIter::new(tt);
         let mut rules = Vec::new();
 
@@ -251,7 +225,7 @@ impl MacroDef {
             validate(&rule.lhs)?;
         }
 
-        Ok(MacroDef { rules, shift: Shift::new(tt) })
+        Ok(DeclarativeMacro { rules, shift: Shift::new(tt) })
     }
 
     pub fn expand(&self, tt: &tt::Subtree) -> ExpandResult<tt::Subtree> {