dep cannot vendor dependencies if parent isn't go-gettable

[rselbach]

What version of dep are you using (dep version)?

dep:
 version     : devel
 build date  :
 git hash    :
 go version  : go1.9.1
 go compiler : gc
 platform    : darwin/amd64

What dep command did you run?

I ran dep init -v on a directory with a single testcase go file (see below). Here's the output --

Getting direct dependencies...
Checked 1 directories for packages.
Found 1 direct dependencies.
Root project is "git.coyotesystems.com/lab/test"
 1 transitively valid internal packages
 1 external packages imported from 1 projects
(0)   ✓ select (root)
(1)	? attempt golang.org/x/sys with 1 pkgs; 1 versions to try
(1)	    try golang.org/x/sys@master
(2)	✗   golang.org/x/sys at master has problem subpkg(s):
(2)	  	golang.org/x/sys/unix has err (scanner.ErrorList); required by (root).
(1)	  ← no more versions of golang.org/x/sys to try; begin backtrack
  ✗ solving failed

Solver wall times by segment:
     b-source-exists: 527.041707ms
         b-list-pkgs: 163.656631ms
         select-root:    128.439µs
            new-atom:     78.595µs
             satisfy:     40.398µs
     b-list-versions:     16.882µs
               other:     11.177µs
  b-deduce-proj-root:      3.077µs

  TOTAL: 690.976906ms

No versions of golang.org/x/sys met constraints:
	master: Could not introduce golang.org/x/sys@master, as its subpackage golang.org/x/sys/unix does not contain usable Go code (scanner.ErrorList).. (Package is required by (root).)

What did you expect to see?

I expected the package golang.org/x/sys/unix to be vendored inside vendor/

What did you see instead?

An error message:

No versions of golang.org/x/sys met constraints:
	master: Could not introduce golang.org/x/sys@master, as its subpackage golang.org/x/sys/unix does not contain usable Go code (scanner.ErrorList).. (Package is required by (root).)

It seems to me as though the problem is dep is trying to go-get golang.org/x/sys instead of golang.org/x/sys/unix.

This could be related to #1306, but not exactly the same as golang.org/x/sys/unix does contain .go files.

Testcase

Here is the simple testcase I used for this --

package main

import (
        "fmt"

        "golang.org/x/sys/unix"
)

func main() {
        a := unix.AF_APPLETALK
        fmt.Println(a)
}

[rselbach]

This was with dep installed with brew. I just tried compiling from master and it seems the bug is gone, so I'm closing it. Seems like the brew version is old?