From 360de5ba71a631a118a088dba7c975e9ae592452 Mon Sep 17 00:00:00 2001
From: Edwin Cheng <edwin0cheng@gmail.com>
Date: Sat, 21 Dec 2019 05:02:31 +0800
Subject: [PATCH 1/2] Recursive collect macros in impl items

---
 crates/ra_hir_def/src/data.rs        | 38 ++++++++++++++++++++--------
 crates/ra_hir_ty/src/tests/macros.rs | 23 +++++++++++++++++
 2 files changed, 51 insertions(+), 10 deletions(-)

diff --git a/crates/ra_hir_def/src/data.rs b/crates/ra_hir_def/src/data.rs
index b0a3f17845..6a65633aef 100644
--- a/crates/ra_hir_def/src/data.rs
+++ b/crates/ra_hir_def/src/data.rs
@@ -226,21 +226,39 @@ fn collect_impl_items_in_macros(
     let mut res = Vec::new();
 
     for m in impl_block.value.syntax().children().filter_map(ast::MacroCall::cast) {
-        if let Some((mark, items)) = expander.enter_expand(db, m) {
-            let items: InFile<ast::MacroItems> = expander.to_source(items);
-            expander.exit(db, mark);
-            res.extend(collect_impl_items(
-                db,
-                items.value.items().filter_map(|it| ImplItem::cast(it.syntax().clone())),
-                items.file_id,
-                id,
-            ));
-        }
+        res.extend(collect_impl_items_in_macro(db, &mut expander, m, id))
     }
 
     res
 }
 
+fn collect_impl_items_in_macro(
+    db: &impl DefDatabase,
+    expander: &mut Expander,
+    m: ast::MacroCall,
+    id: ImplId,
+) -> Vec<AssocItemId> {
+    if let Some((mark, items)) = expander.enter_expand(db, m) {
+        let items: InFile<ast::MacroItems> = expander.to_source(items);
+        let mut res = collect_impl_items(
+            db,
+            items.value.items().filter_map(|it| ImplItem::cast(it.syntax().clone())),
+            items.file_id,
+            id,
+        );
+        // Recursive collect macros
+        // Note that ast::ModuleItem do not include ast::MacroCall
+        // We cannot use ModuleItemOwner::items here
+        for it in items.value.syntax().children().filter_map(ast::MacroCall::cast) {
+            res.extend(collect_impl_items_in_macro(db, expander, it, id))
+        }
+        expander.exit(db, mark);
+        res
+    } else {
+        Vec::new()
+    }
+}
+
 fn collect_impl_items(
     db: &impl DefDatabase,
     impl_items: impl Iterator<Item = ImplItem>,
diff --git a/crates/ra_hir_ty/src/tests/macros.rs b/crates/ra_hir_ty/src/tests/macros.rs
index 7fdbf996f4..69c695cc8f 100644
--- a/crates/ra_hir_ty/src/tests/macros.rs
+++ b/crates/ra_hir_ty/src/tests/macros.rs
@@ -201,6 +201,29 @@ fn test() { S.foo()<|>; }
     assert_eq!(t, "u128");
 }
 
+#[test]
+fn infer_impl_items_generated_by_macros_chain() {
+    let t = type_at(
+        r#"
+//- /main.rs
+macro_rules! m_inner {
+    () => {fn foo(&self) -> u128 {0}}
+}
+macro_rules! m {
+    () => {m_inner!();}
+}
+
+struct S;
+impl S {
+    m!();
+}
+
+fn test() { S.foo()<|>; }
+"#,
+    );
+    assert_eq!(t, "u128");
+}
+
 #[test]
 fn infer_macro_with_dollar_crate_is_correct_in_expr() {
     let (db, pos) = TestDB::with_position(

From c1166697a74bca690443525ced8cd8bc08894779 Mon Sep 17 00:00:00 2001
From: Edwin Cheng <edwin0cheng@gmail.com>
Date: Sat, 21 Dec 2019 05:16:29 +0800
Subject: [PATCH 2/2] Add a limit for protect against infinite recursion

---
 crates/ra_hir_def/src/data.rs | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/crates/ra_hir_def/src/data.rs b/crates/ra_hir_def/src/data.rs
index 6a65633aef..1aa9a9b7d7 100644
--- a/crates/ra_hir_def/src/data.rs
+++ b/crates/ra_hir_def/src/data.rs
@@ -225,8 +225,11 @@ fn collect_impl_items_in_macros(
     let mut expander = Expander::new(db, impl_block.file_id, module_id);
     let mut res = Vec::new();
 
+    // We set a limit to protect against infinite recursion
+    let limit = 100;
+
     for m in impl_block.value.syntax().children().filter_map(ast::MacroCall::cast) {
-        res.extend(collect_impl_items_in_macro(db, &mut expander, m, id))
+        res.extend(collect_impl_items_in_macro(db, &mut expander, m, id, limit))
     }
 
     res
@@ -237,7 +240,12 @@ fn collect_impl_items_in_macro(
     expander: &mut Expander,
     m: ast::MacroCall,
     id: ImplId,
+    limit: usize,
 ) -> Vec<AssocItemId> {
+    if limit == 0 {
+        return Vec::new();
+    }
+
     if let Some((mark, items)) = expander.enter_expand(db, m) {
         let items: InFile<ast::MacroItems> = expander.to_source(items);
         let mut res = collect_impl_items(
@@ -250,7 +258,7 @@ fn collect_impl_items_in_macro(
         // Note that ast::ModuleItem do not include ast::MacroCall
         // We cannot use ModuleItemOwner::items here
         for it in items.value.syntax().children().filter_map(ast::MacroCall::cast) {
-            res.extend(collect_impl_items_in_macro(db, expander, it, id))
+            res.extend(collect_impl_items_in_macro(db, expander, it, id, limit - 1))
         }
         expander.exit(db, mark);
         res