diff --git a/core/data/deconstruct_keys_spec.rb b/core/data/deconstruct_keys_spec.rb
index 5cae4cbd68..df08652f24 100644
--- a/core/data/deconstruct_keys_spec.rb
+++ b/core/data/deconstruct_keys_spec.rb
@@ -84,6 +84,28 @@
     d.deconstruct_keys(nil).should == {x: 1, y: 2}
   end
 
+  it "tries to convert a key with #to_int if index is not a String nor a Symbol, but responds to #to_int" do
+    klass = Data.define(:x, :y)
+    d = klass.new(1, 2)
+
+    key = mock("to_int")
+    key.should_receive(:to_int).and_return(1)
+
+    d.deconstruct_keys([key]).should == { key => 2 }
+  end
+
+  it "raises a TypeError if the conversion with #to_int does not return an Integer" do
+    klass = Data.define(:x, :y)
+    d = klass.new(1, 2)
+
+    key = mock("to_int")
+    key.should_receive(:to_int).and_return("not an Integer")
+
+    -> {
+      d.deconstruct_keys([key])
+    }.should raise_error(TypeError, /can't convert MockObject to Integer/)
+  end
+
   it "raises TypeError if index is not a String, a Symbol and not convertible to Integer " do
     klass = Data.define(:x, :y)
     d = klass.new(1, 2)
diff --git a/core/struct/deconstruct_keys_spec.rb b/core/struct/deconstruct_keys_spec.rb
index 602403d183..1639a1abbb 100644
--- a/core/struct/deconstruct_keys_spec.rb
+++ b/core/struct/deconstruct_keys_spec.rb
@@ -80,6 +80,28 @@
     obj.deconstruct_keys(nil).should == {x: 1, y: 2}
   end
 
+  it "tries to convert a key with #to_int if index is not a String nor a Symbol, but responds to #to_int" do
+    struct = Struct.new(:x, :y)
+    s = struct.new(1, 2)
+
+    key = mock("to_int")
+    key.should_receive(:to_int).and_return(1)
+
+    s.deconstruct_keys([key]).should == { key => 2 }
+  end
+
+  it "raises a TypeError if the conversion with #to_int does not return an Integer" do
+    struct = Struct.new(:x, :y)
+    s = struct.new(1, 2)
+
+    key = mock("to_int")
+    key.should_receive(:to_int).and_return("not an Integer")
+
+    -> {
+      s.deconstruct_keys([key])
+    }.should raise_error(TypeError, /can't convert MockObject to Integer/)
+  end
+
   it "raises TypeError if index is not a String, a Symbol and not convertible to Integer" do
     struct = Struct.new(:x, :y)
     s = struct.new(1, 2)