feat: support embedded generic interfaces

[tra4less]

fixes #668 #658 #700

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[codyoss]

@n0trace Thanks for the PR! Would you be willing to expand support for this test case as well:

type EmbeddingIface interface {
	TwentyOne[other.Three]
	other.Twenty[StructType]
	Foo() error
}

If you don't have the time I can review this as is and this could be done in another PR.

[tra4less]

@n0trace Thanks for the PR! Would you be willing to expand support for this test case as well:

type EmbeddingIface interface {
	TwentyOne[other.Three]
	other.Twenty[StructType]
	Foo() error
}

If you don't have the time I can review this as is and this could be done in another PR.

done @codyoss

[codyoss]

@n0trace Sorry if I was not clear, I meant just copy paste that code literally into generics.go. I don't think this solution covers the case where the outer interface does not contain type parameters, but the inner impl does.

[tra4less]

cases are complex than I have imagined, but done. please review. @codyoss

[tra4less]

fixes #658

[codyoss]

@n0trace I will take a look over the weekend, thank you!

[alexandreLamarre]

As a heads up I verified this also fixes the same issue we were seeing in #658

[codyoss]

Reviewing this today, sorry. Had gotten pulled away from this project for awhile!

[codyoss]

@n0trace I am still digging through the code, but would you mind adding some docs around the new types/fields/methods you added. I know parsing code is lacking this in general right now, but since this adds a bit of complexity it would be nice to have so details of what/how things are being used.

[lennycampino]

@n0trace @codyoss Is there any update on this? :)

[hirikarate]

I'm having the same issue and I'm hoping this fix could make it to official as soon as possible.
Thank you all for the great work.

[chkp-omris]

I'm also having the same issue, could you please review this?

[tofluid]

This is needed, please review. Thanks!

[tra4less]

@codyoss we need a resolution for mock generics. please review.

[paprikati]

We are also blocked on this - would love if we could use this ❤️

[AyushG3112]

@n0trace @codyoss any update on this please?

[samvdb]

Thanks for the pull request. Support for generics would be most welcome! Any update?

[samvdb]

I tested this PR with go version go1.20.1 linux/amd64 and can confirm generics are working.

[tofluid]

@codyoss or anyone else that can approve this PR. My team is really getting hamstrung and we're now starting to consider a different mocking library for go but then that'll be two testing standards which I do not want.

Please get this approved!

[colinschoen]

@codyoss Can you please have a look at this

[tedkornish]

Also eagerly awaiting this.

[maestre3d]

Just looked at Cody's LinkedIn profile. Looks like he got promoted and is no longer part of Google's Golang Developer Relations team.

I think we should ping another person to get this PR merged.

[ShiningRush]

@n0trace hi, I get a error when mock the interface which embedded a another package's pointer and generic types (mockgen is build from your branch):
Loading input failed: unable to parse interface type parameters: Repo

test demo like below:

package a

type ChildRepo interface {
	b.Repo[*b.SomeStruct]
}

package b

type Repo[T any] interface {
}

type SomeStruct struct {
}

It will be ok when I use struct to instead of pointer

type ChildRepo interface {
	b.Repo[b.SomeStruct]
}

[tra4less]

@ShiningRush fixed it

@codyoss I've refactored my implementation, and now it's easy to understand and maintain. I'd appreciate it if you could take some time to review it