去构建找不到由Dep确保的供应商软件包

我遇到了一个错误，即go不能正确解决供应商的程序包；在macOS High Sierra 10.13.6上。我将使用github.com/gorilla/mux作为示例包

$ echo $GOPATH
/Users/gregorysims/go

$ go version
go version go1.11 darwin/amd64 

$ go env
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/gregorysims/Library/Caches/go-build"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOOS="darwin"
GOPATH="/Users/gregorysims/go"
GOPROXY=""
GORACE=""
GOROOT="/usr/local/go"
GOTMPDIR=""
GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64"
GCCGO="gccgo"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_COnFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/tb/6c5vksm558q5q4t0fxfscgy80000gp/T/go-build409352678=/tmp/go-build -gno-record-gcc-switches -fno-common"

我正在导入软件包

import (
    ...
    "github.com/gorilla/mux"
    ...
)

运行时：

go build -o out main.go

对于供应商中的每个包装，我都会收到以下错误

main.go:6:2: cannot find package "_/Users/gregorysims/go/src/site/user/project/vendor/github.com/gorilla/mux" in any of:
/usr/local/go/src/_/Users/gregorysims/go/src/site/user/project/vendor/github.com/gorilla/mux (from $GOROOT)
/Users/gregorysims/go/src/_/Users/gregorysims/go/src/site/user/project/vendor/github.com/gorilla/mux (from $GOPATH)

该文件夹位于

/Users/gregorysims/go/src/site/user/project/vendor/github.com/gorilla/mux

并存在于目录中。

为什么在以下添加前缀？

/Users/gregorysims/go/src/_

更新

删除本地项目并从远程重新克隆后，我尝试在不下载任何依赖项的情况下进行构建。这具有预期的输出：

main.go:6:2: cannot find package "github.com/gorilla/mux" in any of:
/usr/local/go/src/github.com/gorilla/mux (from $GOROOT)
/Users/gregorysims/go/src/github.com/gorilla/mux (from $GOPATH)

仅在运行之后dep ensure运行build命令后，才会产生上述错误。

更新2

创建一个空的供应商目录会将输出更改为：

main.go:6:2: cannot find package "github.com/gorilla/mux" in any of:
/Users/gregorysims/go/src/site/user/project/vendor/github.com/gorilla/mux (vendor tree)
/usr/local/go/src/github.com/gorilla/mux (from $GOROOT)
/Users/gregorysims/go/src/github.com/gorilla/mux (from $GOPATH)

更新3

为了模拟dep，我调用go get github.com/gorilla/mux了以下命令：

mv $GOPATH/src/github.com/gorilla/mux $GOPATH/src/site/user/project/vendor/github.com/gorilla/mux

这样做之后，问题再次浮出水面。