cmd/go: TestScript/gopath_moved_repo flake

[mknyszek]

2022-09-01T23:18:01-a74d46d/linux-amd64-longtest

Might be related to #52820.

CC @bcmills

[bcmills]

The git trace from the test log:

            > [exec:git] ! go get -d -u rsc.io/pdf
            [stderr]
            # cd $WORK/gopath/src/rsc.io/pdf; git pull --ff-only
            23:45:49.720171 http.c:756              == Info: Couldn't find host github.com in the .netrc file; using defaults
            23:45:49.746088 http.c:756              == Info:   Trying 140.82.112.3:443...
            23:45:49.770382 http.c:756              == Info: Connected to github.com (140.82.112.3) port 443 (#0)
…
            remote: Repository not found.
            fatal: Authentication failed for 'https://github.com/rsc/pdfXXX/'
            package rsc.io/pdf: exit status 1
            [exit status 1]

[bcmills]

I don't think this test is supposed to be trying to fetch from github.com/rsc/pdfXXX at all: it is supposed to notice that the go-import path doesn't match and bail at that point.

The repo check is here:
https://cs.opensource.google/go/go/+/master:src/cmd/go/internal/get/get.go;l=466-486;drc=9e6cd3985dbcdcfe0ed2075be6dbe8c5d6de59cb

Notably, if the call to rr.VCS.ResolveRepo fails, the code proceeds with the repo location from GOPATH.

I suspect that in this case that call failed due to #49954 or a related error connecting to rsc.io.

[bcmills]

Probably the long-term fix for this is to migrate the tests away from the external rsc.io server (using the same mechanism as #27494).

[bcmills]

Duplicate of #49954