1 files changed, 145 insertions, 8 deletions
diff --git a/spec/ruby/core/module/name_spec.rb b/spec/ruby/core/module/name_spec.rb
index 0727278591..332c08d782 100644
--- a/spec/ruby/core/module/name_spec.rb
+++ b/spec/ruby/core/module/name_spec.rb
@@ -1,21 +1,69 @@
-require File.expand_path('../../../spec_helper', __FILE__)
-require File.expand_path('../fixtures/module', __FILE__)
+require_relative '../../spec_helper'
+require_relative 'fixtures/module'
 
 describe "Module#name" do
   it "is nil for an anonymous module" do
-    Module.new.name.should be_nil
+    Module.new.name.should == nil
   end
 
-  it "is nil when assigned to a constant in an anonymous module" do
+  it "is not nil when assigned to a constant in an anonymous module" do
     m = Module.new
     m::N = Module.new
-    m::N.name.should be_nil
+    m::N.name.should.end_with? '::N'
   end
 
   it "is not nil for a nested module created with the module keyword" do
     m = Module.new
     module m::N; end
-    m::N.name.should =~ /#<Module:0x[0-9a-f]+>::N/
+    m::N.name.should =~ /\A#<Module:0x[0-9a-f]+>::N\z/
+  end
+
+  it "returns nil for a singleton class" do
+    Module.new.singleton_class.name.should == nil
+    String.singleton_class.name.should == nil
+    Object.new.singleton_class.name.should == nil
+  end
+
+  it "changes when the module is reachable through a constant path" do
+    m = Module.new
+    module m::N; end
+    m::N.name.should =~ /\A#<Module:0x\h+>::N\z/
+    ModuleSpecs::Anonymous::WasAnnon = m::N
+    m::N.name.should == "ModuleSpecs::Anonymous::WasAnnon"
+  ensure
+    ModuleSpecs::Anonymous.send(:remove_const, :WasAnnon)
+  end
+
+  it "may be the repeated in different module objects" do
+    m = Module.new
+    n = Module.new
+
+    suppress_warning do
+      ModuleSpecs::Anonymous::SameName = m
+      ModuleSpecs::Anonymous::SameName = n
+    end
+
+    m.name.should == "ModuleSpecs::Anonymous::SameName"
+    n.name.should == "ModuleSpecs::Anonymous::SameName"
+  end
+
+  it "is set after it is removed from a constant" do
+    module ModuleSpecs
+      module ModuleToRemove
+      end
+
+      mod = ModuleToRemove
+      remove_const(:ModuleToRemove)
+      mod.name.should == "ModuleSpecs::ModuleToRemove"
+    end
+  end
+
+  it "is set after it is removed from a constant under an anonymous module" do
+    m = Module.new
+    module m::Child; end
+    child = m::Child
+    m.send(:remove_const, :Child)
+    child.name.should =~ /\A#<Module:0x\h+>::Child\z/
   end
 
   it "is set when opened with the module keyword" do
@@ -26,10 +74,20 @@ describe "Module#name" do
     ModuleSpecs::Anonymous.name.should == "ModuleSpecs::Anonymous"
   end
 
-  it "is set when assigning to a constant" do
+  it "is set when assigning to a constant (constant path matches outer module name)" do
     m = Module.new
     ModuleSpecs::Anonymous::A = m
     m.name.should == "ModuleSpecs::Anonymous::A"
+  ensure
+    ModuleSpecs::Anonymous.send(:remove_const, :A)
+  end
+
+  it "is set when assigning to a constant (constant path does not match outer module name)" do
+    m = Module.new
+    ModuleSpecs::Anonymous::SameChild::A = m
+    m.name.should == "ModuleSpecs::Anonymous::Child::A"
+  ensure
+    ModuleSpecs::Anonymous::SameChild.send(:remove_const, :A)
   end
 
   it "is not modified when assigning to a new constant after it has been accessed" do
@@ -38,6 +96,18 @@ describe "Module#name" do
     m.name.should == "ModuleSpecs::Anonymous::B"
     ModuleSpecs::Anonymous::C = m
     m.name.should == "ModuleSpecs::Anonymous::B"
+  ensure
+    ModuleSpecs::Anonymous.send(:remove_const, :B)
+    ModuleSpecs::Anonymous.send(:remove_const, :C)
+  end
+
+  it "is not modified when assigned to a different anonymous module" do
+    m = Module.new
+    module m::M; end
+    first_name = m::M.name.dup
+    module m::N; end
+    m::N::F = m::M
+    m::M.name.should == first_name
   end
 
   # http://bugs.ruby-lang.org/issues/6067
@@ -59,10 +129,77 @@ describe "Module#name" do
     ModuleSpecs::NameEncoding.new.name.encoding.should == Encoding::UTF_8
   end
 
-  it "is set when the anonymous outer module name is set" do
+  it "is set when the anonymous outer module name is set (module in one single constant)" do
     m = Module.new
     m::N = Module.new
     ModuleSpecs::Anonymous::E = m
     m::N.name.should == "ModuleSpecs::Anonymous::E::N"
+  ensure
+    ModuleSpecs::Anonymous.send(:remove_const, :E)
+  end
+
+  # https://bugs.ruby-lang.org/issues/19681
+  it "is set when the anonymous outer module name is set (module in several constants)" do
+    m = Module.new
+    m::N = Module.new
+    m::O = m::N
+    ModuleSpecs::Anonymous::StoredInMultiplePlaces = m
+    valid_names = [
+      "ModuleSpecs::Anonymous::StoredInMultiplePlaces::N",
+      "ModuleSpecs::Anonymous::StoredInMultiplePlaces::O"
+    ]
+    valid_names.should.include?(m::N.name) # You get one of the two, but you don't know which one.
+  ensure
+    ModuleSpecs::Anonymous.send(:remove_const, :StoredInMultiplePlaces)
+  end
+
+  it "is set in #const_added callback when a module defined in the top-level scope" do
+    ruby_exe(<<~RUBY, args: "2>&1").chomp.should == "TEST1\nTEST2"
+      class Module
+        def const_added(name)
+          puts const_get(name).name
+        end
+      end
+
+      # module with name
+      module TEST1
+      end
+
+      # anonymous module
+      TEST2 = Module.new
+    RUBY
+  end
+
+  it "is set in #const_added callback for a nested module when an outer module defined in the top-level scope" do
+    ScratchPad.record []
+
+    ModuleSpecs::NameSpecs::NamedModule = Module.new do
+      def self.const_added(name)
+        ScratchPad << const_get(name).name
+      end
+
+      module self::A
+        def self.const_added(name)
+          ScratchPad << const_get(name).name
+        end
+
+        module self::B
+        end
+      end
+    end
+
+    ScratchPad.recorded.should.one?(/#<Module.+>::A$/)
+    ScratchPad.recorded.should.one?(/#<Module.+>::A::B$/)
+    ModuleSpecs::NameSpecs.send :remove_const, :NamedModule
+  end
+
+  it "returns a frozen String" do
+    ModuleSpecs.name.should.frozen?
+  end
+
+  it "always returns the same String for a given Module" do
+    s1 = ModuleSpecs.name
+    s2 = ModuleSpecs.name
+    s1.should.equal?(s2)
   end
 end