cmd/go: misleading error message for replacement module with capital letters #38220
Description
What version of Go are you using (go version)?
$ go version go version go1.14.1 darwin/amd64
What operating system and processor architecture are you using (go env)?
go env Output
$ go env GO111MODULE="" GOARCH="amd64" GOBIN="" GOCACHE="/Users/lstigter/Library/Caches/go-build" GOENV="/Users/lstigter/Library/Application Support/go/env" GOEXE="" GOFLAGS="" GOHOSTARCH="amd64" GOHOSTOS="darwin" GOINSECURE="" GONOPROXY="" GONOSUMDB="" GOOS="darwin" GOPATH="/Users/lstigter/go" GOPRIVATE="" GOPROXY="https://proxy.golang.org,direct" GOROOT="/usr/local/Cellar/go/1.14.1/libexec" GOSUMDB="sum.golang.org" GOTMPDIR="" GOTOOLDIR="/usr/local/Cellar/go/1.14.1/libexec/pkg/tool/darwin_amd64" GCCGO="gccgo" AR="ar" 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/4b/hq3khbrx30b_wk3fz63z9vww0000gq/T/go-build752664778=/tmp/go-build -gno-record-gcc-switches -fno-common"
What did you do?
I forked a project from https://github.com/wavefrontHQ/wavefront-lambda-go which doesn't use Go modules yet to help them adopt Go modules. I created a go.mod file, using
$ go mod init github.com/wavefrontHQ/wavefront-lambda-go
$ go mod tidy
That results in the go.mod file
module github.com/wavefronthq/wavefront-lambda-go
go 1.14
require (
github.com/aws/aws-lambda-go v1.12.1
github.com/rcrowley/go-metrics v0.0.0-20190706150252-9beb055b7962
github.com/wavefronthq/go-metrics-wavefront v0.9.0
)
The resulting code was committed to the forked repo https://github.com/retgits/wavefront-lambda-go
In a project where I want to use this new module, I added a replace directive into my go.mod file to point to the new location
module github.com/retgits/acme-serverless-payment
replace github.com/wavefronthq/wavefront-lambda-go => github.com/retgits/wavefront-lambda-go v0.0.0-20200402174306-c89629d5856a
go 1.13
require (
github.com/aws/aws-lambda-go v1.15.0
github.com/aws/aws-sdk-go v1.29.27
github.com/getsentry/sentry-go v0.5.1
github.com/gofrs/uuid v3.2.0+incompatible
github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
github.com/pulumi/pulumi v1.12.1
github.com/pulumi/pulumi-aws v1.26.0
github.com/retgits/creditcard v0.6.0
github.com/retgits/pulumi-helpers v0.1.3
github.com/wavefronthq/wavefront-lambda-go v0.0.0-20190812171804-d9475d6695cc
gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
gopkg.in/yaml.v2 v2.2.8 // indirect
)
Running any of the go commands throws an error
What did you expect to see?
$go mod tidy
<no errors>
What did you see instead?
$ go mod tidy
go: github.com/retgits/[email protected]: parsing go.mod:
module declares its path as: github.com/wavefrontHQ/wavefront-lambda-go
but was required as: github.com/retgits/wavefront-lambda-go
The error message is a little misleading, and as @jayconrod discovered is about the capitalization of wavefrontHQ. After changing it all to lowercase in the module, it was solved.