fix(engine): handle matches against any struct

apps/engine/lib/engine/search/indexer/extractors/struct_reference.ex

@@ -81,6 +81,12 @@ defmodule Engine.Search.Indexer.Extractors.StructReference do
     Analyzer.current_module(reducer.analysis, Reducer.position(reducer))
   end
 
+  # Any-struct pattern: %_{}
+  defp expand_alias(:_, _reducer), do: :ignored
+
+  # Struct pattern with variable binding: %struct_name{}
+  defp expand_alias(atom, _reducer) when is_atom(atom), do: :ignored
+
   defp expand_alias(alias, %Reducer{} = reducer) do
     {line, column} = reducer.position
 

apps/engine/test/engine/search/indexer/extractors/struct_reference_test.exs

@@ -55,6 +55,24 @@ defmodule Engine.Search.Indexer.Extractors.StructReferenceTest do
       assert decorate(doc, struct.range) == "variable = «%MyStruct{}»"
     end
 
+    test "in an any-struct match on the left side and struct on the right" do
+      {:ok, [struct], doc} = ~q[%_{} = %MyStruct{}] |> index()
+
+      assert struct.type == :struct
+      assert struct.subtype == :reference
+      assert struct.subject == Subject.module(MyStruct)
+      assert decorate(doc, struct.range) == "%_{} = «%MyStruct{}»"
+    end
+
+    test "in an any-struct match with binding on the left side and struct on the right" do
+      {:ok, [struct], doc} = ~q[%str_name{} = %MyStruct{}] |> index()
+
+      assert struct.type == :struct
+      assert struct.subtype == :reference
+      assert struct.subject == Subject.module(MyStruct)
+      assert decorate(doc, struct.range) == "%str_name{} = «%MyStruct{}»"
+    end
+
     test "in a struct reference in params" do
       {:ok, [struct], doc} =
         ~q[
@@ -69,6 +87,24 @@ defmodule Engine.Search.Indexer.Extractors.StructReferenceTest do
       assert decorate(doc, struct.range) == ~S[def my_fn(«%MyStruct{}» = first) do]
     end
 
+    test "in an any-struct pattern in params" do
+      assert {:ok, [], _doc} =
+               ~q[
+        def my_fn(%_{} = first) do
+        end
+        ]
+               |> index()
+    end
+
+    test "in an any-struct pattern with binding in params" do
+      assert {:ok, [], _doc} =
+               ~q[
+        def my_fn(%struct_name{} = first) do
+        end
+        ]
+               |> index()
+    end
+
     test "in nested struct references" do
       {:ok, [outer, inner], doc} =
         ~q[