Minor cleanup

[xiangpengzhao]

1. return nil instead of err when the value of err is nil.
2. fix wrong type.

[sosiouxme]

LGTM but travis is choking on "err" being redefined.

[xiangpengzhao]

The travis log shows:

[WARNING] This version mismatch could lead to differences in execution between this run and the Origin CI systems.
pkg/gitserver/gitserver.go:160: declaration of "err" shadows declaration at pkg/gitserver/gitserver.go:156
pkg/gitserver/gitserver.go:166: declaration of "err" shadows declaration at pkg/gitserver/gitserver.go:156
pkg/gitserver/gitserver.go:174: declaration of "err" shadows declaration at pkg/gitserver/gitserver.go:156
pkg/gitserver/gitserver.go:183: declaration of "err" shadows declaration at pkg/gitserver/gitserver.go:156
pkg/gitserver/gitserver.go:196: declaration of "err" shadows declaration at pkg/gitserver/gitserver.go:156
pkg/gitserver/gitserver.go:200: declaration of "err" shadows declaration at pkg/gitserver/gitserver.go:196
pkg/gitserver/gitserver.go:254: declaration of "err" shadows declaration at pkg/gitserver/gitserver.go:225
pkg/gitserver/gitserver.go:336: declaration of "url" shadows declaration at pkg/gitserver/gitserver.go:9
pkg/gitserver/hooks.go:76: declaration of "err" shadows declaration at pkg/gitserver/hooks.go:57
pkg/gitserver/initializer.go:61: declaration of "err" shadows declaration at pkg/gitserver/initializer.go:44
pkg/gitserver/autobuild/autobuild.go:60: declaration of "err" shadows declaration at pkg/gitserver/autobuild/autobuild.go:42
pkg/gitserver/autobuild/autobuild.go:64: declaration of "err" shadows declaration at pkg/gitserver/autobuild/autobuild.go:60
pkg/gitserver/autobuild/autobuild.go:180: declaration of "err" shadows declaration at pkg/gitserver/autobuild/autobuild.go:146
[ERROR] PID 13137: hack/verify-govet.sh:74: `go tool vet -shadow -shadowstrict $test_dir` exited with status 1.
[INFO]      Stack Trace: 
[INFO]        1: hack/verify-govet.sh:74: `go tool vet -shadow -shadowstrict $test_dir`
[INFO]   Exiting with code 1.
make: *** [verify] Error 1

One of the related code blocks is:

    abs, err := filepath.Abs(home)
    if err != nil {
        return nil, fmt.Errorf("can't make %q absolute: %v", home, err)
    }
    if stat, err := os.Stat(abs); err != nil || !stat.IsDir() {
        return nil, fmt.Errorf("GIT_HOME must be an existing directory: %v", err)
    }

But it seems that we shouldn't modify the code. Then how to solve the travis flake? Should the script hack/verify-govet.sh be modified?

@sosiouxme Thanks!

[knobunc]

LGTM [test]

[xiangpengzhao]

Travis still failed due to the same error as is mentioned in my above comment. How can we solve this? @sosiouxme @knobunc Thanks!

[knobunc]

Flake #11240 (perhaps?) re-[test]

[openshift-bot]

Evaluated for origin test up to c89db5c

[openshift-bot]

continuous-integration/openshift-jenkins/test SUCCESS (https://ci.openshift.redhat.com/jenkins/job/test_pr_origin/10988/) (Base Commit: 6932bcc)