From a31e1e789918073deabaff90a542d7d99e3c262d Mon Sep 17 00:00:00 2001
From: "Stanislav (Stas) Katkov" <git@skatkov.com>
Date: Sat, 29 Aug 2026 16:59:47 +0200
Subject: [PATCH 1/8] RBS cache during scan

---
 lib/rdoc/parser/rbs.rb       | 44 ++++++++++++++--
 test/rdoc/parser/rbs_test.rb | 97 ++++++++++++++++++++++++++++++++++++
 2 files changed, 138 insertions(+), 3 deletions(-)

diff --git a/lib/rdoc/parser/rbs.rb b/lib/rdoc/parser/rbs.rb
index 107e6d0219..29dc60f680 100644
--- a/lib/rdoc/parser/rbs.rb
+++ b/lib/rdoc/parser/rbs.rb
@@ -11,6 +11,8 @@ class RDoc::Parser::RBS < RDoc::Parser
   parse_files_matching RBS_FILE_EXTENSION
 
   def scan
+    @attributes_by_context = {}
+    @methods_by_context = {}
     _, _, decls = ::RBS::Parser.parse_signature(@content)
     decls.each do |decl|
       parse_decl decl, @top_level
@@ -90,12 +92,32 @@ def attr_rw_matches?(existing_rw, new_rw)
     existing_rw.each_char.any? { |rw| new_rw.include? rw }
   end
 
+  def attribute_index(context)
+    @attributes_by_context[context] ||= context.attributes.each_with_object({}) do |attribute, index|
+      index[[attribute.name, attribute.singleton]] ||= attribute
+    end
+  end
+
+  def find_attribute(context, name, singleton)
+    attribute_index(context)[[name, singleton]]
+  end
+
+  def method_index(context)
+    @methods_by_context[context] ||= context.method_list.each_with_object({}) do |method, index|
+      index[[method.name, !!method.singleton]] ||= method
+    end
+  end
+
+  def find_method(context, name, singleton)
+    method_index(context)[[name, singleton]]
+  end
+
   def merge_attribute_methods(context, name, rw, singleton, comment, type_signature_lines)
     method_names = []
     method_names << name if rw.include?('R')
     method_names << "#{name}=" if rw.include?('W')
 
-    methods = method_names.map { |method_name| context.find_method(method_name, singleton) }
+    methods = method_names.map { |method_name| find_method(context, method_name, singleton) }
     methods.compact.each do |method|
       merge_documentation method, comment, type_signature_lines
     end
@@ -135,7 +157,7 @@ def parse_attr_decl(decl, context)
     type_signature_lines = [decl.type.to_s]
     name = decl.name.to_s
     singleton = decl.kind == :singleton
-    if attribute = context.find_attribute(name, singleton)
+    if attribute = find_attribute(context, name, singleton)
       merge_documentation attribute, comment, type_signature_lines if
         attr_rw_matches? attribute.rw, rw
       return
@@ -154,7 +176,11 @@ def parse_attr_decl(decl, context)
     record_object_location attribute, decl.location
     attribute.type_signature_lines = type_signature_lines
     attribute.visibility = decl.visibility if decl.visibility
+    attribute_count = context.attributes.length
     context.add_attribute attribute
+    context.attributes[attribute_count..].each do |added_attribute|
+      attribute_index(context)[[added_attribute.name, added_attribute.singleton]] ||= added_attribute
+    end
   end
 
   def parse_class_decl(decl, context)
@@ -235,7 +261,15 @@ def parse_method_alias_decl(decl, context)
       singleton: decl.kind == :singleton
     )
     record_object_location alias_def, decl.location
+    method_count = context.method_list.length
+    attribute_count = context.attributes.length
     context.add_alias alias_def
+    context.method_list[method_count..].each do |method|
+      method_index(context)[[method.name, !!method.singleton]] ||= method
+    end
+    context.attributes[attribute_count..].each do |attribute|
+      attribute_index(context)[[attribute.name, attribute.singleton]] ||= attribute
+    end
   end
 
   def parse_method_decl(decl, context)
@@ -245,7 +279,7 @@ def parse_method_decl(decl, context)
     singleton = rdoc_method_singleton?(decl)
     visibility = rdoc_method_visibility(decl)
 
-    if method = context.find_method(method_name, singleton)
+    if method = find_method(context, method_name, singleton)
       merge_documentation method, comment, type_signature_lines
       return
     end
@@ -261,7 +295,11 @@ def parse_method_decl(decl, context)
 
     method.comment = comment if comment
     method.visibility = visibility if visibility
+    method_count = context.method_list.length
     context.add_method method
+    context.method_list[method_count..].each do |added_method|
+      method_index(context)[[added_method.name, !!added_method.singleton]] ||= added_method
+    end
   end
 
   def parse_module_decl(decl, context)
diff --git a/test/rdoc/parser/rbs_test.rb b/test/rdoc/parser/rbs_test.rb
index 0365462cc1..d90b3d9ff1 100644
--- a/test/rdoc/parser/rbs_test.rb
+++ b/test/rdoc/parser/rbs_test.rb
@@ -143,6 +143,71 @@ def greet: () -> String
     assert_equal ['() -> String'], greet.type_signature_lines
   end
 
+  def test_scan_finds_existing_method_after_store_index_rebuild
+    ruby_top_level = @store.add_file 'sample.rb'
+    sample = ruby_top_level.add_class RDoc::NormalClass, 'Sample'
+
+    name = RDoc::AnyMethod.new 'name'
+    name.record_location ruby_top_level
+    sample.add_method name
+
+    name_writer = RDoc::Attr.new 'name', 'W', nil
+    name_writer.record_location ruby_top_level
+    sample.add_attribute name_writer
+
+    util_parser("class Sample\nend\n").scan
+    @store.clear_file_contributions @filename, keep_position: true
+    util_parser(<<~RBS).scan
+      class Sample
+        def name: () -> String
+      end
+    RBS
+
+    assert_equal ['() -> String'], name.type_signature_lines
+  end
+
+  def test_scan_indexes_forward_method_and_attribute_aliases
+    util_parser(<<~RBS).scan
+      class Sample
+        # Method alias docs.
+        alias salutation greet
+        alias display_name name
+
+        def greet: () -> String
+        # Base attribute docs.
+        attr_reader name: String
+
+        # Dedicated method docs.
+        def salutation: () -> String
+        # Dedicated attribute docs.
+        attr_reader display_name: String
+      end
+    RBS
+
+    sample = @store.find_class_named 'Sample'
+    salutation = sample.find_method 'salutation', false
+    display_name = sample.find_attribute 'display_name', false
+
+    assert_equal "Method alias docs.\n---\nDedicated method docs.", salutation.comment.to_s.strip
+    assert_equal "Base attribute docs.\n---\nDedicated attribute docs.", display_name.comment.to_s.strip
+  end
+
+  def test_scan_treats_legacy_nil_singleton_as_instance_method
+    ruby_top_level = @store.add_file 'sample.rb'
+    sample = ruby_top_level.add_class RDoc::NormalClass, 'Sample'
+    greet = RDoc::AnyMethod.new 'greet'
+    greet.singleton = nil
+    sample.add_method greet
+
+    util_parser(<<~RBS).scan
+      class Sample
+        def greet: () -> String
+      end
+    RBS
+
+    assert_equal ['() -> String'], greet.type_signature_lines
+  end
+
   def test_scan_preserves_rbs_markdown_when_extending_method_documentation
     ruby_top_level = @store.add_file 'sample.rb'
     sample = ruby_top_level.add_class RDoc::NormalClass, 'Sample'
@@ -266,6 +331,38 @@ class PrivateSample
     assert_equal :public, private_constructor.visibility
   end
 
+  def test_scan_method_lookup_is_linear
+    name_calls = 0
+    original_name = RDoc::AnyMethod.instance_method :name
+    RDoc::AnyMethod.define_method(:name) do
+      name_calls += 1
+      original_name.bind_call self
+    end
+
+    methods = 100.times.map { |i| "  def m#{i}: () -> void" }.join("\n")
+    util_parser("class C\n#{methods}\nend\n").scan
+
+    assert_operator name_calls, :<=, 1_000
+  ensure
+    RDoc::AnyMethod.define_method :name, original_name
+  end
+
+  def test_scan_attribute_lookup_is_linear
+    name_calls = 0
+    original_name = RDoc::Attr.instance_method :name
+    RDoc::Attr.define_method(:name) do
+      name_calls += 1
+      original_name.bind_call self
+    end
+
+    attributes = 100.times.map { |i| "  attr_reader a#{i}: String" }.join("\n")
+    util_parser("class C\n#{attributes}\nend\n").scan
+
+    assert_operator name_calls, :<=, 1_000
+  ensure
+    RDoc::Attr.remove_method :name
+  end
+
   def util_parser(content)
     RDoc::Parser::RBS.new @top_level, content, @options, @stats
   end

From 3b578179226b6d547bcfcd0af66653fa9140660a Mon Sep 17 00:00:00 2001
From: "Stanislav (Stas) Katkov" <git@skatkov.com>
Date: Sun, 30 Aug 2026 14:20:02 +0200
Subject: [PATCH 2/8] Lazily update RBS member indexes

Context#add_alias can append methods or attributes as a side effect, making
mutation-side cache updates depend on Context internals. Index each
collection's unconsumed tail during lookup instead, keeping synchronization
in one place while preserving linear lookup.
---
 lib/rdoc/parser/rbs.rb | 24 ++++++------------------
 1 file changed, 6 insertions(+), 18 deletions(-)

diff --git a/lib/rdoc/parser/rbs.rb b/lib/rdoc/parser/rbs.rb
index 29dc60f680..2101456495 100644
--- a/lib/rdoc/parser/rbs.rb
+++ b/lib/rdoc/parser/rbs.rb
@@ -93,9 +93,11 @@ def attr_rw_matches?(existing_rw, new_rw)
   end
 
   def attribute_index(context)
-    @attributes_by_context[context] ||= context.attributes.each_with_object({}) do |attribute, index|
+    index = @attributes_by_context[context] ||= {}
+    context.attributes[index.length..].each do |attribute|
       index[[attribute.name, attribute.singleton]] ||= attribute
     end
+    index
   end
 
   def find_attribute(context, name, singleton)
@@ -103,9 +105,11 @@ def find_attribute(context, name, singleton)
   end
 
   def method_index(context)
-    @methods_by_context[context] ||= context.method_list.each_with_object({}) do |method, index|
+    index = @methods_by_context[context] ||= {}
+    context.method_list[index.length..].each do |method|
       index[[method.name, !!method.singleton]] ||= method
     end
+    index
   end
 
   def find_method(context, name, singleton)
@@ -176,11 +180,7 @@ def parse_attr_decl(decl, context)
     record_object_location attribute, decl.location
     attribute.type_signature_lines = type_signature_lines
     attribute.visibility = decl.visibility if decl.visibility
-    attribute_count = context.attributes.length
     context.add_attribute attribute
-    context.attributes[attribute_count..].each do |added_attribute|
-      attribute_index(context)[[added_attribute.name, added_attribute.singleton]] ||= added_attribute
-    end
   end
 
   def parse_class_decl(decl, context)
@@ -261,15 +261,7 @@ def parse_method_alias_decl(decl, context)
       singleton: decl.kind == :singleton
     )
     record_object_location alias_def, decl.location
-    method_count = context.method_list.length
-    attribute_count = context.attributes.length
     context.add_alias alias_def
-    context.method_list[method_count..].each do |method|
-      method_index(context)[[method.name, !!method.singleton]] ||= method
-    end
-    context.attributes[attribute_count..].each do |attribute|
-      attribute_index(context)[[attribute.name, attribute.singleton]] ||= attribute
-    end
   end
 
   def parse_method_decl(decl, context)
@@ -295,11 +287,7 @@ def parse_method_decl(decl, context)
 
     method.comment = comment if comment
     method.visibility = visibility if visibility
-    method_count = context.method_list.length
     context.add_method method
-    context.method_list[method_count..].each do |added_method|
-      method_index(context)[[added_method.name, !!added_method.singleton]] ||= added_method
-    end
   end
 
   def parse_module_decl(decl, context)

From 88028c633caa61586a34a1e5ad3ba406f5ee9f2e Mon Sep 17 00:00:00 2001
From: "Stanislav (Stas) Katkov" <git@skatkov.com>
Date: Sun, 30 Aug 2026 14:43:46 +0200
Subject: [PATCH 3/8] remove method mocking tests

---
 test/rdoc/parser/rbs_test.rb | 32 --------------------------------
 1 file changed, 32 deletions(-)

diff --git a/test/rdoc/parser/rbs_test.rb b/test/rdoc/parser/rbs_test.rb
index d90b3d9ff1..5199b61831 100644
--- a/test/rdoc/parser/rbs_test.rb
+++ b/test/rdoc/parser/rbs_test.rb
@@ -331,38 +331,6 @@ class PrivateSample
     assert_equal :public, private_constructor.visibility
   end
 
-  def test_scan_method_lookup_is_linear
-    name_calls = 0
-    original_name = RDoc::AnyMethod.instance_method :name
-    RDoc::AnyMethod.define_method(:name) do
-      name_calls += 1
-      original_name.bind_call self
-    end
-
-    methods = 100.times.map { |i| "  def m#{i}: () -> void" }.join("\n")
-    util_parser("class C\n#{methods}\nend\n").scan
-
-    assert_operator name_calls, :<=, 1_000
-  ensure
-    RDoc::AnyMethod.define_method :name, original_name
-  end
-
-  def test_scan_attribute_lookup_is_linear
-    name_calls = 0
-    original_name = RDoc::Attr.instance_method :name
-    RDoc::Attr.define_method(:name) do
-      name_calls += 1
-      original_name.bind_call self
-    end
-
-    attributes = 100.times.map { |i| "  attr_reader a#{i}: String" }.join("\n")
-    util_parser("class C\n#{attributes}\nend\n").scan
-
-    assert_operator name_calls, :<=, 1_000
-  ensure
-    RDoc::Attr.remove_method :name
-  end
-
   def util_parser(content)
     RDoc::Parser::RBS.new @top_level, content, @options, @stats
   end

From 7e63a454c404da56edbb0ab1e42bca2bfe717fc9 Mon Sep 17 00:00:00 2001
From: "Stanislav (Stas) Katkov" <git@skatkov.com>
Date: Sun, 30 Aug 2026 14:54:06 +0200
Subject: [PATCH 4/8] Revived both RBS linear-performance tests using
 assert_linear_performance

---
 test/rdoc/parser/rbs_test.rb | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/test/rdoc/parser/rbs_test.rb b/test/rdoc/parser/rbs_test.rb
index 5199b61831..a94153ef70 100644
--- a/test/rdoc/parser/rbs_test.rb
+++ b/test/rdoc/parser/rbs_test.rb
@@ -331,6 +331,20 @@ class PrivateSample
     assert_equal :public, private_constructor.visibility
   end
 
+  def test_scan_method_lookup_linear_performance
+    assert_linear_performance([1, 10, 100]) do |factor|
+      methods = (factor * 200).times.map { |i| "  def m#{i}: () -> void" }.join("\n")
+      util_parser("class C\n#{methods}\nend\n").scan
+    end
+  end
+
+  def test_scan_attribute_lookup_linear_performance
+    assert_linear_performance([1, 10, 100]) do |factor|
+      attributes = (factor * 200).times.map { |i| "  attr_reader a#{i}: String" }.join("\n")
+      util_parser("class C\n#{attributes}\nend\n").scan
+    end
+  end
+
   def util_parser(content)
     RDoc::Parser::RBS.new @top_level, content, @options, @stats
   end

From 558f2cc5b0fe535087e3441a7119569bee592596 Mon Sep 17 00:00:00 2001
From: "Stanislav (Stas) Katkov" <git@skatkov.com>
Date: Sun, 30 Aug 2026 16:17:01 +0200
Subject: [PATCH 5/8] remove finder methods

---
 lib/rdoc/parser/rbs.rb | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/lib/rdoc/parser/rbs.rb b/lib/rdoc/parser/rbs.rb
index 2101456495..c2421cf00c 100644
--- a/lib/rdoc/parser/rbs.rb
+++ b/lib/rdoc/parser/rbs.rb
@@ -100,10 +100,6 @@ def attribute_index(context)
     index
   end
 
-  def find_attribute(context, name, singleton)
-    attribute_index(context)[[name, singleton]]
-  end
-
   def method_index(context)
     index = @methods_by_context[context] ||= {}
     context.method_list[index.length..].each do |method|
@@ -112,16 +108,12 @@ def method_index(context)
     index
   end
 
-  def find_method(context, name, singleton)
-    method_index(context)[[name, singleton]]
-  end
-
   def merge_attribute_methods(context, name, rw, singleton, comment, type_signature_lines)
     method_names = []
     method_names << name if rw.include?('R')
     method_names << "#{name}=" if rw.include?('W')
 
-    methods = method_names.map { |method_name| find_method(context, method_name, singleton) }
+    methods = method_names.map { |method_name| method_index(context)[[method_name, singleton]] }
     methods.compact.each do |method|
       merge_documentation method, comment, type_signature_lines
     end
@@ -161,7 +153,7 @@ def parse_attr_decl(decl, context)
     type_signature_lines = [decl.type.to_s]
     name = decl.name.to_s
     singleton = decl.kind == :singleton
-    if attribute = find_attribute(context, name, singleton)
+    if attribute = attribute_index(context)[[name, singleton]]
       merge_documentation attribute, comment, type_signature_lines if
         attr_rw_matches? attribute.rw, rw
       return
@@ -271,7 +263,7 @@ def parse_method_decl(decl, context)
     singleton = rdoc_method_singleton?(decl)
     visibility = rdoc_method_visibility(decl)
 
-    if method = find_method(context, method_name, singleton)
+    if method = method_index(context)[[method_name, singleton]]
       merge_documentation method, comment, type_signature_lines
       return
     end

From 78a6b4ea5409bdfc0047e94d3440e2f4667c5b35 Mon Sep 17 00:00:00 2001
From: "Stanislav (Stas) Katkov" <git@skatkov.com>
Date: Sun, 30 Aug 2026 16:17:15 +0200
Subject: [PATCH 6/8] simplify singleton setup

---
 test/rdoc/parser/rbs_test.rb | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/test/rdoc/parser/rbs_test.rb b/test/rdoc/parser/rbs_test.rb
index a94153ef70..d8ddf29b9c 100644
--- a/test/rdoc/parser/rbs_test.rb
+++ b/test/rdoc/parser/rbs_test.rb
@@ -195,8 +195,7 @@ def salutation: () -> String
   def test_scan_treats_legacy_nil_singleton_as_instance_method
     ruby_top_level = @store.add_file 'sample.rb'
     sample = ruby_top_level.add_class RDoc::NormalClass, 'Sample'
-    greet = RDoc::AnyMethod.new 'greet'
-    greet.singleton = nil
+    greet = RDoc::AnyMethod.new 'greet', singleton: nil
     sample.add_method greet
 
     util_parser(<<~RBS).scan

From e7f3e015e5fa86a5d2658594b906b7250bba784a Mon Sep 17 00:00:00 2001
From: "Stanislav (Stas) Katkov" <git@skatkov.com>
Date: Sun, 30 Aug 2026 16:17:25 +0200
Subject: [PATCH 7/8] combine two tests into one

---
 test/rdoc/parser/rbs_test.rb | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/test/rdoc/parser/rbs_test.rb b/test/rdoc/parser/rbs_test.rb
index d8ddf29b9c..9f0a95fcd0 100644
--- a/test/rdoc/parser/rbs_test.rb
+++ b/test/rdoc/parser/rbs_test.rb
@@ -330,17 +330,10 @@ class PrivateSample
     assert_equal :public, private_constructor.visibility
   end
 
-  def test_scan_method_lookup_linear_performance
+  def test_scan_member_lookup_linear_performance
     assert_linear_performance([1, 10, 100]) do |factor|
-      methods = (factor * 200).times.map { |i| "  def m#{i}: () -> void" }.join("\n")
-      util_parser("class C\n#{methods}\nend\n").scan
-    end
-  end
-
-  def test_scan_attribute_lookup_linear_performance
-    assert_linear_performance([1, 10, 100]) do |factor|
-      attributes = (factor * 200).times.map { |i| "  attr_reader a#{i}: String" }.join("\n")
-      util_parser("class C\n#{attributes}\nend\n").scan
+      members = Array.new(factor * 200) { |i| "  def m#{i}: () -> void\n  attr_reader a#{i}: String" }.join("\n")
+      util_parser("class C\n#{members}\nend\n").scan
     end
   end
 

From 3c1659f3119f7cd0def99b354cbefa2ff3210fe3 Mon Sep 17 00:00:00 2001
From: "Stanislav (Stas) Katkov" <git@skatkov.com>
Date: Tue, 1 Sep 2026 18:50:50 +0200
Subject: [PATCH 8/8] Use index from Context

---
 lib/rdoc/code_object/context.rb | 18 ++++++++++++++++--
 lib/rdoc/parser/rbs.rb          | 24 +++---------------------
 test/rdoc/parser/rbs_test.rb    | 24 +-----------------------
 test/rdoc/parser/ruby_test.rb   |  7 +++++++
 test/rdoc/rdoc_context_test.rb  | 20 ++++++++++++++++++++
 5 files changed, 47 insertions(+), 46 deletions(-)

diff --git a/lib/rdoc/code_object/context.rb b/lib/rdoc/code_object/context.rb
index ccc9203141..da85909742 100644
--- a/lib/rdoc/code_object/context.rb
+++ b/lib/rdoc/code_object/context.rb
@@ -186,8 +186,8 @@ def add(klass, name, comment)
   def add_alias(an_alias)
     return an_alias unless @document_self
 
-    method_attr = find_method(an_alias.old_name, an_alias.singleton) ||
-                  find_attribute(an_alias.old_name, an_alias.singleton)
+    method_attr = find_method_from_hash(an_alias.old_name, an_alias.singleton) ||
+                  find_attribute_from_hash(an_alias.old_name, an_alias.singleton)
 
     if method_attr
       method_attr.add_alias an_alias, self
@@ -749,6 +749,14 @@ def find_attribute(name, singleton)
     @attributes.find { |a| a.name == name && a.singleton == singleton }
   end
 
+  def find_attribute_from_hash(name, singleton) # :nodoc:
+    name = name.delete_suffix('=')
+    key = "#{singleton ? '::' : '#'}#{name}"
+    attribute = @methods_hash[key]
+    attribute = @methods_hash["#{key}="] unless RDoc::Attr === attribute
+    attribute if RDoc::Attr === attribute && attribute.singleton == singleton
+  end
+
   ##
   # Finds an attribute with +name+ in this context
 
@@ -843,6 +851,12 @@ def find_method(name, singleton)
     }
   end
 
+  def find_method_from_hash(name, singleton) # :nodoc:
+    method = @methods_hash["#{singleton ? '::' : '#'}#{name}"]
+    # ponytail: keep the fallback until incremental rebuilds make this hash canonical.
+    RDoc::Attr === method ? find_method(name, singleton) : method
+  end
+
   ##
   # Finds a instance or module method with +name+ in this context
 
diff --git a/lib/rdoc/parser/rbs.rb b/lib/rdoc/parser/rbs.rb
index c2421cf00c..ff3b68a43b 100644
--- a/lib/rdoc/parser/rbs.rb
+++ b/lib/rdoc/parser/rbs.rb
@@ -11,8 +11,6 @@ class RDoc::Parser::RBS < RDoc::Parser
   parse_files_matching RBS_FILE_EXTENSION
 
   def scan
-    @attributes_by_context = {}
-    @methods_by_context = {}
     _, _, decls = ::RBS::Parser.parse_signature(@content)
     decls.each do |decl|
       parse_decl decl, @top_level
@@ -92,28 +90,12 @@ def attr_rw_matches?(existing_rw, new_rw)
     existing_rw.each_char.any? { |rw| new_rw.include? rw }
   end
 
-  def attribute_index(context)
-    index = @attributes_by_context[context] ||= {}
-    context.attributes[index.length..].each do |attribute|
-      index[[attribute.name, attribute.singleton]] ||= attribute
-    end
-    index
-  end
-
-  def method_index(context)
-    index = @methods_by_context[context] ||= {}
-    context.method_list[index.length..].each do |method|
-      index[[method.name, !!method.singleton]] ||= method
-    end
-    index
-  end
-
   def merge_attribute_methods(context, name, rw, singleton, comment, type_signature_lines)
     method_names = []
     method_names << name if rw.include?('R')
     method_names << "#{name}=" if rw.include?('W')
 
-    methods = method_names.map { |method_name| method_index(context)[[method_name, singleton]] }
+    methods = method_names.map { |method_name| context.find_method_from_hash(method_name, singleton) }
     methods.compact.each do |method|
       merge_documentation method, comment, type_signature_lines
     end
@@ -153,7 +135,7 @@ def parse_attr_decl(decl, context)
     type_signature_lines = [decl.type.to_s]
     name = decl.name.to_s
     singleton = decl.kind == :singleton
-    if attribute = attribute_index(context)[[name, singleton]]
+    if attribute = context.find_attribute_from_hash(name, singleton)
       merge_documentation attribute, comment, type_signature_lines if
         attr_rw_matches? attribute.rw, rw
       return
@@ -263,7 +245,7 @@ def parse_method_decl(decl, context)
     singleton = rdoc_method_singleton?(decl)
     visibility = rdoc_method_visibility(decl)
 
-    if method = method_index(context)[[method_name, singleton]]
+    if method = context.find_method_from_hash(method_name, singleton)
       merge_documentation method, comment, type_signature_lines
       return
     end
diff --git a/test/rdoc/parser/rbs_test.rb b/test/rdoc/parser/rbs_test.rb
index 9f0a95fcd0..7b22d26255 100644
--- a/test/rdoc/parser/rbs_test.rb
+++ b/test/rdoc/parser/rbs_test.rb
@@ -166,47 +166,25 @@ def name: () -> String
     assert_equal ['() -> String'], name.type_signature_lines
   end
 
-  def test_scan_indexes_forward_method_and_attribute_aliases
+  def test_scan_indexes_forward_attribute_alias
     util_parser(<<~RBS).scan
       class Sample
-        # Method alias docs.
-        alias salutation greet
         alias display_name name
 
-        def greet: () -> String
         # Base attribute docs.
         attr_reader name: String
 
-        # Dedicated method docs.
-        def salutation: () -> String
         # Dedicated attribute docs.
         attr_reader display_name: String
       end
     RBS
 
     sample = @store.find_class_named 'Sample'
-    salutation = sample.find_method 'salutation', false
     display_name = sample.find_attribute 'display_name', false
 
-    assert_equal "Method alias docs.\n---\nDedicated method docs.", salutation.comment.to_s.strip
     assert_equal "Base attribute docs.\n---\nDedicated attribute docs.", display_name.comment.to_s.strip
   end
 
-  def test_scan_treats_legacy_nil_singleton_as_instance_method
-    ruby_top_level = @store.add_file 'sample.rb'
-    sample = ruby_top_level.add_class RDoc::NormalClass, 'Sample'
-    greet = RDoc::AnyMethod.new 'greet', singleton: nil
-    sample.add_method greet
-
-    util_parser(<<~RBS).scan
-      class Sample
-        def greet: () -> String
-      end
-    RBS
-
-    assert_equal ['() -> String'], greet.type_signature_lines
-  end
-
   def test_scan_preserves_rbs_markdown_when_extending_method_documentation
     ruby_top_level = @store.add_file 'sample.rb'
     sample = ruby_top_level.add_class RDoc::NormalClass, 'Sample'
diff --git a/test/rdoc/parser/ruby_test.rb b/test/rdoc/parser/ruby_test.rb
index 40cc6f4893..2020f9f715 100644
--- a/test/rdoc/parser/ruby_test.rb
+++ b/test/rdoc/parser/ruby_test.rb
@@ -2722,6 +2722,13 @@ def test_read_directive_linear_performance
     end
   end
 
+  def test_alias_lookup_linear_performance
+    assert_linear_performance([1, 10, 100]) do |factor|
+      methods = Array.new(factor * 100) { |i| "  def m#{i}; end\n  alias a#{i} m#{i}" }.join("\n")
+      util_parser "class C#{factor}\n#{methods}\nend\n"
+    end
+  end
+
   def test_code_object_token_stream
     util_parser <<~RUBY
       class Foo
diff --git a/test/rdoc/rdoc_context_test.rb b/test/rdoc/rdoc_context_test.rb
index d193b324cd..ae54651f30 100644
--- a/test/rdoc/rdoc_context_test.rb
+++ b/test/rdoc/rdoc_context_test.rb
@@ -541,6 +541,16 @@ def test_find_attribute_named
     assert_equal 'RW', @c1.find_attribute_named('attr_accessor').rw
   end
 
+  def test_find_attribute_from_hash
+    singleton = RDoc::Attr.new 'singleton', 'R', nil, singleton: true
+    @context.add_attribute singleton
+
+    assert_same @c1.find_attribute_named('attr_reader'), @c1.find_attribute_from_hash('attr_reader', false)
+    assert_same @c1.find_attribute_named('attr_writer'), @c1.find_attribute_from_hash('attr_writer=', false)
+    assert_same singleton, @context.find_attribute_from_hash('singleton', true)
+    assert_nil @c1.find_attribute_from_hash('attr_reader', true)
+  end
+
   def test_find_class_method_named
     assert_nil @c1.find_class_method_named('none')
 
@@ -584,6 +594,16 @@ def test_find_method
     assert_equal @c2_b, loaded_c2.find_method('b', nil)
   end
 
+  def test_find_method_from_hash
+    instance = RDoc::AnyMethod.new 'instance', singleton: nil
+    @context.add_method instance
+
+    assert_same instance, @context.find_method_from_hash('instance', false)
+    assert_same instance, @context.find_method_from_hash('instance', nil)
+    assert_same @c1__m, @c1.find_method_from_hash('m', true)
+    assert_nil @c1.find_method_from_hash('attr', false)
+  end
+
   def test_find_method_named
     assert_equal true, @c1.find_method_named('m').singleton
   end