EqualExportedValues can compare two slices

[redachl]

Description

EqualExportedValues does not handle slices for now, although Equal and EqualValues compare each element of 2 slices.

Proposed solution

Removing the check that the provided variables are structs or pointers to structs here allows comparing two slices. https://github.com/stretchr/testify/blob/352d2438b9da776308844714c38c0c9a16f3b5b6/assert/assertions.go#L629

~Happy to propose a PR if you agree with this design!~

I made a PR to remove the described checks.

Use case

The implementation of EqualExportedValues can actually compare slices, if they are inside a struct.

Here is an example.

func TestSomething(t *testing.T) {
    type sliceWrapper struct {
        ExportedSlice []int
    }
    a := sliceWrapper{ExportedSlice: []int{1, 2, 3}}
    b := sliceWrapper{ExportedSlice: []int{1, 2, 3}}

    assert.Equal(t, a.ExportedSlice, b.ExportedSlice)               // OK
    assert.EqualValues(t, a.ExportedSlice, b.ExportedSlice)         // OK
    assert.EqualExportedValues(t, a.ExportedSlice, b.ExportedSlice) // Types expected to both be struct or pointer to struct

    // Possible workaround: use a struct wrapper.
    assert.Equal(t, a, b)               // OK
    assert.EqualValues(t, a, b)         // OK
    assert.EqualExportedValues(t, a, b) // OK
}   

[Antonboom]

The word Exported binds this function to structs, not to specific struct's field.

See the doc:

// EqualExportedValues asserts that the types of two objects are equal and their public fields are also equal.

How does this relate to slices and why is this function expected to behave the same as Equal and EqualValues?

Looks like nonsense.

[redachl]

That's one way to look at it.

But I think it's also a pity that you have to use a slice wrapper when testing a function that returns a slice. Especially when it's a slice of proto messages, which with the latest code generation have unexported fields.

Another option is to add a new function, but I'm not sure it's the best thing to do.

Or we just accept using a slice wrapper is enough.

[brackendawson]

For me it's key that the doc says "objects", which is not defined in the go spec, and not "structs". I think this leaves scope for nested structs (already supported) and structs nested in other container types.