Merge #3392

3392: Implement concat eager macro  r=matklad a=edwin0cheng

This PR implements the following things:

1. Add basic eager macro infrastructure by introducing `EagerCallId` such that the new `MacroCallId` is defined as :

```
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub enum MacroCallId {
    LazyMacro(LazyMacroId),
    EagerMacro(EagerMacroId),
}
```

2. Add `concat!` builtin macro.




Co-authored-by: Edwin Cheng <[email protected]>

Author: bors[bot]

crates/ra_hir_def/src/lib.rs

@@ -47,8 +47,8 @@ mod marks;
 use std::hash::Hash;
 
 use hir_expand::{
-    ast_id_map::FileAstId, db::AstDatabase, hygiene::Hygiene, AstId, HirFileId, InFile,
-    MacroCallId, MacroCallKind, MacroDefId,
+    ast_id_map::FileAstId, db::AstDatabase, eager::expand_eager_macro, hygiene::Hygiene, AstId,
+    HirFileId, InFile, MacroCallId, MacroCallKind, MacroDefId, MacroDefKind,
 };
 use ra_arena::{impl_arena_id, RawId};
 use ra_db::{impl_intern_key, salsa, CrateId};
@@ -459,8 +459,21 @@ impl AsMacroCall for AstIdWithPath<ast::MacroCall> {
         db: &impl AstDatabase,
         resolver: impl Fn(path::ModPath) -> Option<MacroDefId>,
     ) -> Option<MacroCallId> {
-        let def = resolver(self.path.clone())?;
-        Some(def.as_call_id(db, MacroCallKind::FnLike(self.ast_id)))
+        let def: MacroDefId = resolver(self.path.clone())?;
+
+        if let MacroDefKind::BuiltInEager(_) = def.kind {
+            let macro_call = InFile::new(self.ast_id.file_id, self.ast_id.to_node(db));
+            let hygiene = Hygiene::new(db, self.ast_id.file_id);
+
+            Some(
+                expand_eager_macro(db, macro_call, def, &|path: ast::Path| {
+                    resolver(path::ModPath::from_src(path, &hygiene)?)
+                })?
+                .into(),
+            )
+        } else {
+            Some(def.as_lazy_macro(db, MacroCallKind::FnLike(self.ast_id)).into())
+        }
     }
 }
 
@@ -471,6 +484,6 @@ impl AsMacroCall for AstIdWithPath<ast::ModuleItem> {
         resolver: impl Fn(path::ModPath) -> Option<MacroDefId>,
     ) -> Option<MacroCallId> {
         let def = resolver(self.path.clone())?;
-        Some(def.as_call_id(db, MacroCallKind::Attr(self.ast_id)))
+        Some(def.as_lazy_macro(db, MacroCallKind::Attr(self.ast_id)).into())
     }
 }

crates/ra_hir_expand/src/builtin_derive.rs

@@ -9,7 +9,7 @@ use ra_syntax::{
 };
 
 use crate::db::AstDatabase;
-use crate::{name, quote, MacroCallId, MacroDefId, MacroDefKind};
+use crate::{name, quote, LazyMacroId, MacroDefId, MacroDefKind};
 
 macro_rules! register_builtin {
     ( $($trait:ident => $expand:ident),* ) => {
@@ -22,7 +22,7 @@ macro_rules! register_builtin {
             pub fn expand(
                 &self,
                 db: &dyn AstDatabase,
-                id: MacroCallId,
+                id: LazyMacroId,
                 tt: &tt::Subtree,
             ) -> Result<tt::Subtree, mbe::ExpandError> {
                 let expander = match *self {
@@ -155,71 +155,71 @@ fn expand_simple_derive(
 
 fn copy_expand(
     _db: &dyn AstDatabase,
-    _id: MacroCallId,
+    _id: LazyMacroId,
     tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     expand_simple_derive(tt, quote! { std::marker::Copy })
 }
 
 fn clone_expand(
     _db: &dyn AstDatabase,
-    _id: MacroCallId,
+    _id: LazyMacroId,
     tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     expand_simple_derive(tt, quote! { std::clone::Clone })
 }
 
 fn default_expand(
     _db: &dyn AstDatabase,
-    _id: MacroCallId,
+    _id: LazyMacroId,
     tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     expand_simple_derive(tt, quote! { std::default::Default })
 }
 
 fn debug_expand(
     _db: &dyn AstDatabase,
-    _id: MacroCallId,
+    _id: LazyMacroId,
     tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     expand_simple_derive(tt, quote! { std::fmt::Debug })
 }
 
 fn hash_expand(
     _db: &dyn AstDatabase,
-    _id: MacroCallId,
+    _id: LazyMacroId,
     tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     expand_simple_derive(tt, quote! { std::hash::Hash })
 }
 
 fn eq_expand(
     _db: &dyn AstDatabase,
-    _id: MacroCallId,
+    _id: LazyMacroId,
     tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     expand_simple_derive(tt, quote! { std::cmp::Eq })
 }
 
 fn partial_eq_expand(
     _db: &dyn AstDatabase,
-    _id: MacroCallId,
+    _id: LazyMacroId,
     tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     expand_simple_derive(tt, quote! { std::cmp::PartialEq })
 }
 
 fn ord_expand(
     _db: &dyn AstDatabase,
-    _id: MacroCallId,
+    _id: LazyMacroId,
     tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     expand_simple_derive(tt, quote! { std::cmp::Ord })
 }
 
 fn partial_ord_expand(
     _db: &dyn AstDatabase,
-    _id: MacroCallId,
+    _id: LazyMacroId,
     tt: &tt::Subtree,
 ) -> Result<tt::Subtree, mbe::ExpandError> {
     expand_simple_derive(tt, quote! { std::cmp::PartialOrd })
@@ -228,7 +228,7 @@ fn partial_ord_expand(
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::{test_db::TestDB, AstId, MacroCallKind, MacroCallLoc};
+    use crate::{test_db::TestDB, AstId, MacroCallId, MacroCallKind, MacroCallLoc};
     use ra_db::{fixture::WithFixture, SourceDatabase};
 
     fn expand_builtin_derive(s: &str, expander: BuiltinDeriveExpander) -> String {
@@ -248,7 +248,7 @@ mod tests {
             kind: MacroCallKind::Attr(AstId::new(file_id.into(), ast_id_map.ast_id(&items[0]))),
         };
 
-        let id = db.intern_macro(loc);
+        let id: MacroCallId = db.intern_macro(loc).into();
         let parsed = db.parse_or_expand(id.as_file()).unwrap();
 
         // FIXME text() for syntax nodes parsed from token tree looks weird