From 4a7071d0f83c9caa1811c587314461c422f54827 Mon Sep 17 00:00:00 2001
From: Soutaro Matsumoto <matsumoto@soutaro.com>
Date: Tue, 5 Apr 2022 11:23:22 +0900
Subject: [PATCH] Toplevel constant must have the lowlevel precedence

---
 lib/rbs/resolver/constant_resolver.rb       |  7 +++++--
 test/rbs/resolver/constant_resolver_test.rb | 23 +++++++++++++++++++++
 2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/lib/rbs/resolver/constant_resolver.rb b/lib/rbs/resolver/constant_resolver.rb
index 9c670111b..02b1aac86 100644
--- a/lib/rbs/resolver/constant_resolver.rb
+++ b/lib/rbs/resolver/constant_resolver.rb
@@ -106,12 +106,17 @@ def load_context_constants(context)
         # @type var consts: Hash[Symbol, Constant]
         consts = {}
 
+        # Toplevel constants has the lowest precedence
+        consts.merge!(table.toplevel)
         if context
           if last = context[1]
+            # Ancestor constants has the next precedence
             constants_from_ancestors(last, constants: consts)
           end
         end
+        # Context (module nesting) constants has the next precedence
         constants_from_context(context, constants: consts) or return
+        # The constant itself comes the last
         constants_itself(context, constants: consts)
 
         context_constants_cache[context] = consts
@@ -152,8 +157,6 @@ def constants_from_context(context, constants:)
             consts = table.children(last) or return false
             constants.merge!(consts)
           end
-        else
-          constants.merge!(table.toplevel)
         end
 
         true
diff --git a/test/rbs/resolver/constant_resolver_test.rb b/test/rbs/resolver/constant_resolver_test.rb
index 7b7fd0ef5..de88b6b1f 100644
--- a/test/rbs/resolver/constant_resolver_test.rb
+++ b/test/rbs/resolver/constant_resolver_test.rb
@@ -282,4 +282,27 @@ class Stuff
       end
     end
   end
+
+  def test_reference_constant_toplevel
+    SignatureManager.new do |manager|
+      manager.files[Pathname("foo.rbs")] = <<EOF
+CONST: Integer
+
+class Foo
+  CONST: String
+end
+
+class Bar < Foo
+end
+EOF
+      manager.build do |env|
+        builder = DefinitionBuilder.new(env: env)
+        resolver = Resolver::ConstantResolver.new(builder: builder)
+
+        resolver.resolve(:CONST, context: [nil, TypeName("::Bar")]).tap do |constant|
+          assert_equal "::Foo::CONST", constant.name.to_s
+        end
+      end
+    end
+  end
 end