errors when GO111MODULE=off

[bhcleek]

Description

Revive exits non-zero and outputs an error, "linting - retrieving failures channel: command go list: exit status 1," when run against a null module or with module support turned off.

To Reproduce

1. Update revive to v1.3.9
2. set GO111MODULE=off
3. Execute revive against a package that is placed properly in GOPATH

Note that the problem will also manifest when revive is executed against a package that is not in a module at all and is also not in GOPATH.

Expected behavior
Appropriate linting errors should be displayed.

Additional context

This works fine in v1.3.7 and lower; it's a new problem in v1.3.9. If you want some files to use, vim-go's test-fixtures may be useful. The files in the test-fixture for its lint tests are relevant. Here's output showing v1.3.7 vs v1.3.9 behavior:

With v1.3.7:

❯❯❯ GO111MODULE=off GOPATH=$PWD/autoload/go/test-fixtures/lint revive .
lint.go:1:1: should have a package comment
quux.go:5:1: exported function AlsoMissingDoc should have comment or be unexported
lint.go:5:1: exported function MissingDoc should have comment or be unexported

With v1.3.9:

❯❯❯ GO111MODULE=off GOPATH=$PWD/autoload/go/test-fixtures/lint revive .
linting - retrieving failures channel: command go list: exit status 1

[chavacava]

Hi @bhcleek thanks for reporting the problem.
I've tested the PR #1025 against your example and it seems to fix the bug.

[bhcleek]

@chavacava #1025 only fixes the case where GO111MODULE is off and revive is being run against a package that is within in a module. The problem I reported still exists when the package being checked does not have a go.mod file.

Should I open another issue?

[chavacava]

@bhcleek thanks for reporting the problem, I've created a new issue #1027