Cannot use dep ensure on Windows

[sas1024]

What version of Go (go version) and dep (git describe --tags) are you using?

go version go1.8.3 windows/amd64
dep v0.1.0-206-ge99676b

What dep command did you run?

dep ensure -v

What did you expect to see?

Normal working of dep ensure :)

What did you see instead?

An error: both d:\Documents\Projects\Go\src\github.com\sas1024\project and D:\Documents\Projects\Go\src\github.com\sas1024\project are in the same GOPATH d:\Documents\Projects\Go

It's very strange, that's hard drive letter case is differs in paths. There is normal letter and capital letter.

[ibrasho]

@sas1024 Thanks for reporting this.

It looks like we are not handling case-insensitive filesystems properly. I'm really interested in how we got two different cases for the same path. 🤔

I have a planned fix for this and some other path-related bugs. I'm just waiting to be sure if it fixes most of the bugs.

[sdboyer]

@sas1024 does this reproduce consistently for you?

[sas1024]

@sdboyer i'm sorry for delay.
Yes, this error reproduced with dep v0.1.0-300-g310c2c8

[sdboyer]

i know we have at least some code that deals with case insensitivity in the volume name correctly, but apparently we don't have all the cases covered :(

[ibrasho]

@sdboyer I believe you mean HasFilepathPrefix.

The comparison in context.go uses ==. Can I use HasFilepathPrefix to check for equality (if the length is the same and one path is a prefix for the other)?

I was planning to add a function to compare paths wrt case-sensitivity depending on the file system... but I'm not sure at the moment if that's the best solution.

[sdboyer]

Can I use HasFilepathPrefix to check for equality (if the length is the same and one path is a prefix for the other)?

Yep, that should work fine.

[sas1024]

Any news, guys?

It reproduced on dep v0.3.0-142-g6ca8a48.
Without fixing this bug for now is not possible to use dep on Windows systems :(

[klauern]

@sas1024 I think that pull #940 is supposed to fix it, but it hasn't been merged in. I would direct your comment towards that pull request. I believe this issue is blocking for me too, but that is an error on golang tip, so maybe not.

[niondir]

@sas1024 Just and Idea, a fix could be to change your GOPATH from d:\Documents\Projects\Go to D:\Documents\Projects\Go - does that solve you issue?

[klauern]

@niondir I think that could fix @sas1024's, issue, but it does seem like it's something that would be discovered in Go 1.9: golang/go@78a11c2

[sas1024]

@niondir in this case i've got this error:
both d:\Documents\Projects\Go\src\github.com\sas1024\project and D:\Documents\Projects\Go\src\github.com\sas1024\project are in the same GOPATH D:\Documents\Projects\Go

[ibrasho]

@sas1024 I'd appreciate it if you could try the code in #940 to ensure it solves the issue.

[sas1024]

@ibrasho with this changes dep works excelent!