1 files changed, 90 insertions, 0 deletions
diff --git a/spec/ruby/core/kernel/inspect_spec.rb b/spec/ruby/core/kernel/inspect_spec.rb
new file mode 100644
index 0000000000..1fa66cab98
--- /dev/null
+++ b/spec/ruby/core/kernel/inspect_spec.rb
@@ -0,0 +1,90 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+
+describe "Kernel#inspect" do
+  it "returns a String" do
+    Object.new.inspect.should be_an_instance_of(String)
+  end
+
+  it "does not call #to_s if it is defined" do
+    # We must use a bare Object here
+    obj = Object.new
+    inspected = obj.inspect
+
+    obj.stub!(:to_s).and_return("to_s'd")
+
+    obj.inspect.should == inspected
+  end
+
+  it "returns a String with the object class and object_id encoded" do
+    obj = Object.new
+    obj.inspect.should =~ /^#<Object:0x[0-9a-f]+>$/
+  end
+
+  it "returns a String for an object without #class method" do
+    obj = Object.new
+    class << obj
+      undef_method :class
+    end
+    obj.inspect.should be_kind_of(String)
+  end
+
+  ruby_version_is "4.0" do
+    it "calls #instance_variables_to_inspect private method to know which variables to display" do
+      obj = Object.new
+      obj.instance_eval do
+        @host = "localhost"
+        @user = "root"
+        @password = "hunter2"
+      end
+      obj.singleton_class.class_eval do
+        private def instance_variables_to_inspect = %i[@host @user @does_not_exist]
+      end
+
+      inspected = obj.inspect.sub(/^#<Object:0x[0-9a-f]+/, '#<Object:0x00')
+      inspected.should == '#<Object:0x00 @host="localhost", @user="root">'
+
+      obj = Object.new
+      obj.instance_eval do
+        @host = "localhost"
+        @user = "root"
+        @password = "hunter2"
+      end
+      obj.singleton_class.class_eval do
+        private def instance_variables_to_inspect = []
+      end
+
+      inspected = obj.inspect.sub(/^#<Object:0x[0-9a-f]+/, '#<Object:0x00')
+      inspected.should == "#<Object:0x00>"
+    end
+
+    it "displays all instance variables if #instance_variables_to_inspect returns nil" do
+      obj = Object.new
+      obj.instance_eval do
+        @host = "localhost"
+        @user = "root"
+        @password = "hunter2"
+      end
+      obj.singleton_class.class_eval do
+        private def instance_variables_to_inspect = nil
+      end
+
+      inspected = obj.inspect.sub(/^#<Object:0x[0-9a-f]+/, '#<Object:0x00')
+      inspected.should ==  %{#<Object:0x00 @host="localhost", @user="root", @password="hunter2">}
+    end
+
+    it "raises an error if #instance_variables_to_inspect returns an invalid value" do
+      obj = Object.new
+      obj.instance_eval do
+        @host = "localhost"
+        @user = "root"
+        @password = "hunter2"
+      end
+      obj.singleton_class.class_eval do
+        private def instance_variables_to_inspect = {}
+      end
+
+      ->{ obj.inspect }.should raise_error(TypeError, "Expected #instance_variables_to_inspect to return an Array or nil, but it returned Hash")
+    end
+  end
+end