1 files changed, 320 insertions, 16 deletions
diff --git a/test/ruby/test_alias.rb b/test/ruby/test_alias.rb
index 83f897fb00..539cd49488 100644
--- a/test/ruby/test_alias.rb
+++ b/test/ruby/test_alias.rb
@@ -1,40 +1,344 @@
+# frozen_string_literal: false
 require 'test/unit'
 
 class TestAlias < Test::Unit::TestCase
   class Alias0
-    def foo; "foo" end
+    def foo
+      "foo"
+    end
   end
-  class Alias1<Alias0
+
+  class Alias1 < Alias0
     alias bar foo
-    def foo; "foo+" + super end
+
+    def foo
+      "foo+#{super}"
+    end
   end
-  class Alias2<Alias1
+
+  class Alias2 < Alias1
     alias baz foo
     undef foo
   end
-  class Alias3<Alias2
+
+  class Alias3 < Alias2
     def foo
-      defined? super
+      super
     end
+
     def bar
-      defined? super
+      super
     end
+
     def quux
-      defined? super
+      super
     end
   end
 
+  class Alias4 < Alias0
+    alias foo1 foo
+    alias foo2 foo1
+    alias foo3 foo2
+  end
+
+  class Alias5 < Alias4
+    alias foo1 foo
+    alias foo3 foo2
+    alias foo2 foo1
+  end
+
   def test_alias
     x = Alias2.new
-    assert_equal("foo", x.bar)
-    assert_equal("foo+foo", x.baz)
-
-    # test_check for cache
-    assert_equal("foo+foo", x.baz)
+    assert_equal "foo", x.bar
+    assert_equal "foo+foo", x.baz
+    assert_equal "foo+foo", x.baz   # test_check for cache
 
     x = Alias3.new
-    assert(!x.foo)
-    assert(x.bar)
-    assert(!x.quux)
+    assert_raise(NoMethodError) { x.foo }
+    assert_equal "foo", x.bar
+    assert_raise(NoMethodError) { x.quux }
+  end
+
+  def test_alias_inspect
+    o = Alias4.new
+    assert_equal("TestAlias::Alias4(TestAlias::Alias0)#foo()", o.method(:foo).inspect.split[1])
+    assert_equal("TestAlias::Alias4(TestAlias::Alias0)#foo1(foo)()", o.method(:foo1).inspect.split[1])
+    assert_equal("TestAlias::Alias4(TestAlias::Alias0)#foo2(foo)()", o.method(:foo2).inspect.split[1])
+    assert_equal("TestAlias::Alias4(TestAlias::Alias0)#foo3(foo)()", o.method(:foo3).inspect.split[1])
+
+    o = Alias5.new
+    assert_equal("TestAlias::Alias5(TestAlias::Alias0)#foo()", o.method(:foo).inspect.split[1])
+    assert_equal("TestAlias::Alias5(TestAlias::Alias0)#foo1(foo)()", o.method(:foo1).inspect.split[1])
+    assert_equal("TestAlias::Alias5(TestAlias::Alias0)#foo2(foo)()", o.method(:foo2).inspect.split[1])
+    assert_equal("TestAlias::Alias5(TestAlias::Alias0)#foo3(foo)()", o.method(:foo3).inspect.split[1])
+  end
+
+  def test_nonexistmethod
+    assert_raise(NameError){
+      Class.new{
+        alias_method :foobarxyzzy, :barbaz
+      }
+    }
+  end
+
+  def test_send_alias
+    x = "abc"
+    class << x
+      alias_method :try, :__send__
+    end
+    assert_equal("ABC", x.try(:upcase), '[ruby-dev:38824]')
+  end
+
+  def test_special_const_alias
+    assert_raise(TypeError) do
+      1.instance_eval do
+        alias to_string to_s
+      end
+    end
+  end
+
+  def test_alias_with_zsuper_method
+    c = Class.new
+    c.class_eval do
+      def foo
+        :ok
+      end
+      def bar
+        :ng
+      end
+      private :foo
+    end
+    d = Class.new(c)
+    d.class_eval do
+      public :foo
+      alias bar foo
+    end
+    assert_equal(:ok, d.new.bar)
+  end
+
+  module SuperInAliasedModuleMethod
+    module M
+      def foo
+        super << :M
+      end
+
+      alias bar foo
+    end
+
+    class Base
+      def foo
+        [:Base]
+      end
+    end
+
+    class Derived < Base
+      include M
+    end
+  end
+
+  # [ruby-dev:46028]
+  def test_super_in_aliased_module_method # fails in 1.8
+    assert_equal([:Base, :M], SuperInAliasedModuleMethod::Derived.new.bar)
+  end
+
+  def test_alias_wb_miss
+    assert_normal_exit "#{<<-"begin;"}\n#{<<-'end;'}"
+    begin;
+      require 'stringio'
+      GC.verify_internal_consistency
+      GC.start
+      class StringIO
+        alias_method :read_nonblock, :sysread
+      end
+      GC.verify_internal_consistency
+    end;
+  end
+
+  def test_cyclic_zsuper
+    bug9475 = '[ruby-core:60431] [Bug #9475]'
+
+    a = Module.new do
+      def foo
+        "A"
+      end
+    end
+
+    b = Class.new do
+      include a
+      attr_reader :b
+
+      def foo
+        @b ||= 0
+        raise SystemStackError if (@b += 1) > 1
+        # "foo from B"
+        super + "B"
+      end
+    end
+
+    c = Class.new(b) do
+      alias orig_foo foo
+
+      def foo
+        # "foo from C"
+        orig_foo + "C"
+      end
+    end
+
+    b.class_eval do
+      alias orig_foo foo
+      attr_reader :b2
+
+      def foo
+        @b2 ||= 0
+        raise SystemStackError if (@b2 += 1) > 1
+        # "foo from B (again)"
+        orig_foo + "B2"
+      end
+    end
+
+    assert_nothing_raised(SystemStackError, bug9475) do
+      assert_equal("ABC", c.new.foo, bug9475)
+    end
+  end
+
+  def test_alias_in_module
+    bug9663 = '[ruby-core:61635] [Bug #9663]'
+
+    assert_separately(['-', bug9663], "#{<<-"begin;"}\n#{<<-'end;'}")
+    begin;
+      bug = ARGV[0]
+
+      m = Module.new do
+        alias orig_to_s to_s
+      end
+
+      o = Object.new.extend(m)
+      assert_equal(o.to_s, o.orig_to_s, bug)
+    end;
+  end
+
+  class C0; def foo; end; end
+  class C1 < C0; alias bar foo; end
+
+  def test_alias_method_equation
+    obj = C1.new
+    assert_equal(obj.method(:bar), obj.method(:foo))
+    assert_equal(obj.method(:foo), obj.method(:bar))
+  end
+
+  def test_alias_class_method_added
+    name = nil
+    k = Class.new {
+      def foo;end
+      def self.method_added(mid)
+        @name = instance_method(mid).original_name
+      end
+      alias bar foo
+      name = @name
+    }
+    assert_equal(:foo, k.instance_method(:bar).original_name)
+    assert_equal(:foo, name)
+  end
+
+  def test_alias_module_method_added
+    name = nil
+    k = Module.new {
+      def foo;end
+      def self.method_added(mid)
+        @name = instance_method(mid).original_name
+      end
+      alias bar foo
+      name = @name
+    }
+    assert_equal(:foo, k.instance_method(:bar).original_name)
+    assert_equal(:foo, name)
+  end
+
+  def test_alias_suppressing_redefinition
+    assert_in_out_err(%w[-w], "#{<<~"begin;"}\n#{<<~'end;'}")
+    begin;
+      class A
+        def foo; end
+        alias foo foo
+        def foo; end
+      end
+    end;
+  end
+
+  class C2
+    public :system
+    alias_method :bar, :system
+    alias_method :system, :bar
+  end
+
+  def test_zsuper_alias_visibility
+    assert(C2.new.respond_to?(:system))
+  end
+
+  def test_alias_memory_leak
+    assert_no_memory_leak([], "#{<<~"begin;"}", "#{<<~'end;'}", rss: true)
+    begin;
+      class A
+        500.times do
+          1000.times do |i|
+            define_method(:"foo_#{i}") {}
+
+            alias :"foo_#{i}" :"foo_#{i}"
+
+            remove_method :"foo_#{i}"
+          end
+          GC.start
+        end
+      end
+    end;
+  end
+
+  def test_alias_complemented_method
+    assert_in_out_err(%w[-w], "#{<<~"begin;"}\n#{<<~'end;'}")
+    begin;
+      module M
+        def foo = 1
+        self.extend M
+      end
+
+      3.times{|i|
+        module M
+          alias foo2 foo
+          remove_method :foo
+          def foo = 2
+        ensure
+          remove_method :foo
+          alias foo foo2
+          remove_method :foo2
+        end
+
+        M.foo
+
+        original_foo = M.method(:foo)
+
+        M.class_eval do
+          remove_method :foo
+          def foo = 3
+        end
+
+        M.class_eval do
+          remove_method :foo
+          define_method :foo, original_foo
+        end
+      }
+    end;
+  end
+
+  def test_undef_method_error_message_with_zsuper_method
+    modules = [
+      Module.new { private :class },
+      Module.new { prepend Module.new { private :class } },
+    ]
+    message = "undefined method 'class' for module '%s'"
+    modules.each do |mod|
+      assert_raise_with_message(NameError, message % mod) do
+        mod.alias_method :xyz, :class
+      end
+    end
   end
 end