inspect not returning ruby String in jruby-9.0.0.0

[monkstone]

In ruby-processing I have created jruby extensions Vec2D and Vec3D (ie written in java but loaded as ruby classes at runtime). See:-
https://github.com/jashkenas/ruby-processing/tree/master/ext/processing/vecmath/vec2
https://github.com/jashkenas/ruby-processing/tree/master/ext/processing/vecmath/vec3

When I run rspec with jruby-9.0.0.0-SNAPSHOT (2.2.0p0) 2015-01-24 6a608c2 OpenJDK 64-Bit Server VM 25.31-b07 on 1.8.0_31-b13 +jit [linux-amd64]. I get the following

Failures:

  1) Vec2D#inspect should return a String
     Failure/Error: expect(a.inspect).to eq 'Vec2D(x = 3.0000, y = 2.0000)'
       
       expected: "Vec2D(x = 3.0000, y = 2.0000)"
            got: "Vec2D:0x565b064f"
       
       (compared using ==)
     # ./vecmath_spec.rb:242:in `(root)'

  2) Vec3D#inspect should return a String
     Failure/Error: expect(a.inspect).to eq 'Vec3D(x = 3.0000, y = 5.0000, z = 2.0000)'
       
       expected: "Vec3D(x = 3.0000, y = 5.0000, z = 2.0000)"
            got: "Vec3D:0x5ef0d29e"

Actually got: #< wrapped code > inside '' but if I did not edit above you would only see a #
Tests pass with jruby-1.7.18, do I need to explicitly create my own inspect with jruby-9.0.0.0?
PS this issue #1740 is still outstanding @headius

[monkstone]

I am guessing here but in jruby-1.7.18 I did not need to explicitly implement inspect for my jruby extension classes (Vec2D and Vec3D), because inspect correctly does alias inspect to_s and returns the expected result. For whatever reason my Vec2D, Vec3D classes with jruby 9000 are seen as being java objects? @headius

[monkstone]

    @JRubyMethod(name = {"to_s", "inspect"})

    public IRubyObject to_s(ThreadContext context) {
        return context.getRuntime().newString(String.format("Vec3D(x = %4.4f, y = %4.4f, z = %4.4f)", jx, jy, jz));
    }

This fixes the issue for the Vec3D class, but I am asking the question:-
Is the changed behaviour a design change or did it happen by accident?
Further if the change is desired/required there should be some documentation...
@headius

[monkstone]

@headius In case it was accidental I've created a minimal test (to reproduce the issue) https://github.com/ruby-processing/extension-inspect

clone the repo then rake to compile the extension class and run test. See README.md