rust-lang · ChayimFriedman2 · Jun 12, 2025 · Jun 12, 2025
diff --git a/crates/hir-def/src/macro_expansion_tests/mod.rs b/crates/hir-def/src/macro_expansion_tests/mod.rs
@@ -14,7 +14,7 @@ mod builtin_fn_macro;
 mod mbe;
 mod proc_macros;
 
-use std::{iter, ops::Range, sync};
+use std::{any::TypeId, iter, ops::Range, sync};
 
 use base_db::RootQueryDb;
 use expect_test::Expect;
@@ -380,4 +380,8 @@ impl ProcMacroExpander for IdentityWhenValidProcMacroExpander {
             panic!("got invalid macro input: {:?}", parse.errors());
         }
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
diff --git a/crates/hir-expand/src/proc_macro.rs b/crates/hir-expand/src/proc_macro.rs
@@ -34,9 +34,7 @@ pub trait ProcMacroExpander: fmt::Debug + Send + Sync + RefUnwindSafe + Any {
         current_dir: String,
     ) -> Result<tt::TopSubtree, ProcMacroExpansionError>;
 
-    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
-        other.type_id() == self.type_id()
-    }
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool;
 }
 
 impl PartialEq for dyn ProcMacroExpander {

diff --git a/crates/load-cargo/src/lib.rs b/crates/load-cargo/src/lib.rs
@@ -2,7 +2,7 @@
 //! for incorporating changes.
 // Note, don't remove any public api from this. This API is consumed by external tools
 // to run rust-analyzer as a library.
-use std::{collections::hash_map::Entry, mem, path::Path, sync};
+use std::{any::Any, collections::hash_map::Entry, mem, path::Path, sync};
 
 use crossbeam_channel::{Receiver, unbounded};
 use hir_expand::proc_macro::{
@@ -512,6 +512,10 @@ impl ProcMacroExpander for Expander {
             Err(err) => Err(ProcMacroExpansionError::System(err.to_string())),
         }
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        (other as &dyn Any).downcast_ref::<Self>() == Some(self)
+    }
 }
 
 #[cfg(test)]

diff --git a/crates/test-fixture/src/lib.rs b/crates/test-fixture/src/lib.rs
@@ -1,5 +1,5 @@
 //! A set of high-level utility fixture methods to use in tests.
-use std::{mem, str::FromStr, sync};
+use std::{any::TypeId, mem, str::FromStr, sync};
 
 use base_db::{
     Crate, CrateDisplayName, CrateGraphBuilder, CrateName, CrateOrigin, CrateWorkspaceData,
@@ -677,6 +677,10 @@ impl ProcMacroExpander for IdentityProcMacroExpander {
     ) -> Result<TopSubtree, ProcMacroExpansionError> {
         Ok(subtree.clone())
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
 
 // Expands to a macro_rules! macro, for issue #18089.
@@ -708,6 +712,10 @@ impl ProcMacroExpander for Issue18089ProcMacroExpander {
             #subtree
         })
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
 
 // Pastes the attribute input as its output
@@ -728,6 +736,10 @@ impl ProcMacroExpander for AttributeInputReplaceProcMacroExpander {
             .cloned()
             .ok_or_else(|| ProcMacroExpansionError::Panic("Expected attribute input".into()))
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
 
 #[derive(Debug)]
@@ -759,6 +771,10 @@ impl ProcMacroExpander for Issue18840ProcMacroExpander {
         top_subtree_delimiter_mut.close = def_site;
         Ok(result)
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
 
 #[derive(Debug)]
@@ -790,6 +806,10 @@ impl ProcMacroExpander for MirrorProcMacroExpander {
         traverse(&mut builder, input.iter());
         Ok(builder.build())
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
 
 // Replaces every literal with an empty string literal and every identifier with its first letter,
@@ -830,6 +850,10 @@ impl ProcMacroExpander for ShortenProcMacroExpander {
             }
         }
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
 
 // Reads ident type within string quotes, for issue #17479.
@@ -855,6 +879,10 @@ impl ProcMacroExpander for Issue17479ProcMacroExpander {
             #symbol()
         })
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
 
 // Reads ident type within string quotes, for issue #17479.
@@ -906,6 +934,10 @@ impl ProcMacroExpander for Issue18898ProcMacroExpander {
             }
         })
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
 
 // Reads ident type within string quotes, for issue #17479.
@@ -933,6 +965,10 @@ impl ProcMacroExpander for DisallowCfgProcMacroExpander {
         }
         Ok(subtree.clone())
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }
 
 // Generates a new type by adding a suffix to the original name
@@ -987,4 +1023,8 @@ impl ProcMacroExpander for GenerateSuffixedTypeProcMacroExpander {
 
         Ok(ret)
     }
+
+    fn eq_dyn(&self, other: &dyn ProcMacroExpander) -> bool {
+        other.type_id() == TypeId::of::<Self>()
+    }
 }