Show power-assert style errors in error summary

[Qix-]

Trying to get t.same() to work.

The test line I have is

t.same(cc.rgb(), {color: {model: 'rgb', value: [0, 0, 0, 1]}});

Seems fairly straightforward.

Here is the output.

  ✖ models › rgb
  t.same(cc.rgb(), { color: { model: 'rgb', value: [0, 0, 0, 1] } })
            |
            Object{color:Object{model:"rgb",value:[0,0,0,1]}}


  1 test failed

  1. models › rgb
  AssertionError: {} === { color: { model: 'rgb', value: [ 0, 0, 0, 1 ] } }
    Test.fn (models.js:6:4)
    handleMessage (child_process.js:322:10)
    Pipe.channel.onread (child_process.js:349:11)


npm ERR! Test failed.  See above for more details.

Are these not the same objects?

{ color: { model: 'rgb', value: [0, 0, 0, 1] } }

and

Object{color:Object{model:"rgb",value:[0,0,0,1]}}

?

As well, what's up with this?

AssertionError: {} === { color: { model: 'rgb', value: [ 0, 0, 0, 1 ] } }

What's going on here?

[Qix-]

Aha.

t.same() isn't checking non-enumerable properties (color on the object returned from cc.rgb() in the above example wasn't enumerable).

Is this desired?

The workaround is this:

t.same(cc.rgb().color, {model: 'rgb', value: [0, 0, 0, 1]});

Which won't give me as nice output if cc.rgb() returns something that doesn't have an object property color (Javascript will throw an error instead of power-assert showing me the values):

  ✖ models › rgb failed with "Cannot read property 'color' of null"

  1 test failed

  1. models › rgb
  TypeError: Cannot read property 'color' of null
    Test.fn (models.js:8:9)
    handleMessage (child_process.js:322:10)
    Pipe.channel.onread (child_process.js:349:11)

I'd much rather power-assert's pretty output.

[novemberborn]

t.same() isn't checking non-enumerable properties (color on the object returned from cc.rgb() in the above example wasn't enumerable).

Is this desired?

Oh interesting! We use only-shallow under the hood which uses Object.keys().

I'm not sure what the correct behavior is. I imagine non-enumerable properties are often used for internal properties so requiring them to be present in the expected value would be problematic. That would preclude t.same() from comparing such properties.

Would be helpful if power-assert could list such properties, perhaps with an annotation. E.g.:

AssertionError: { color [non-enumerable]: { model: 'rgb', value: [ 0, 0, 0, 1 ] } } === { color: { model: 'rgb', value: [ 0, 0, 0, 1 ] } }

@twada?

[twada]

I think, the correct behavior of t.same is the same as assert.deepEqual

Only enumerable "own" properties are considered. The deepEqual() implementation does not test object prototypes, attached symbols, or non-enumerable properties.

"Deep" equality means that the enumerable "own" properties of child objects are evaluated also.

Assert Node.js v5.9.1 Manual & Documentation

[novemberborn]

@twada yes agreed. I wonder though if the error message could highlight non-enumerables so you stand a better chance of debugging your tests.

[twada]

The graph below is a power-assert output.

  ✖ models › rgb
  t.same(cc.rgb(), { color: { model: 'rgb', value: [0, 0, 0, 1] } })
            |
            Object{color:Object{model:"rgb",value:[0,0,0,1]}}

However, message below is not produced by power-assert (but maybe by core-assert) ?

1. models › rgb
  AssertionError: {} === { color: { model: 'rgb', value: [ 0, 0, 0, 1 ] } }
    Test.fn (models.js:6:4)

Therefore, it's nothing to do with power-assert currently.

It's nice to enhance default assertion message of base assertion library by power-assert, but also I think it's a bit overkill.

[novemberborn]

Oh I hadn't realized we had different output. Why wouldn't we repeat the initial output in the error summary? @jamestalmage?

[Qix-]

I'm fine with it failing due to non-enumerable properties though the lack of decent output explaining it caused me test-related blockage which I hate D:

Making those stand out would be great, if even it still fails (which is completey okay).

[novemberborn]

With #1341 we have much improved value formatting and consistent object comparisons.