Improve unit test coverage in pkg/util/taints/

[mengjiao-liu]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

The changes are as follows:

• Improve test coverage: add unit tests in pkg/util/tail
• Improve test readability by fixing previous code variables that could easily be changed

Run test coverage command:

go test -cover ./pkg/util/taints

Befor:

ok      k8s.io/kubernetes/pkg/util/taints       0.752s  coverage: 89.0% of statements

After（When unused methods are removed, test coverage becomes 100% #112436）:

ok      k8s.io/kubernetes/pkg/util/taints       0.932s  coverage: 98.7% of statements

Which issue(s) this PR fixes:

Ref #97355

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[mengjiao-liu]

/sig testing
/area test

[mengjiao-liu]

/assign @dchen1107

[mengjiao-liu]

/kind cleanup
/remove-kind feature

[mengjiao-liu]

Rebased.

[mengjiao-liu]

/retest

[mengjiao-liu]

ping @lavalamp @dchen1107

[mengjiao-liu]

This PR has been waiting for a review for a long time. Could you please take a look at this PR？@dchen1107 @dims @lavalamp @smarterclayton @thockin

[alculquicondor]

/unassign

feel free to proceed without my review.

[mengjiao-liu]

Please review again and determine if you can agree. Thanks! @MadhavJivrajani

[mengjiao-liu]

The modification has been completed. Request approval @dims @MadhavJivrajani

[oomichi]

Nice work

/triage accepted
/lgtm

[mengjiao-liu]

PR #112436 has been merged, and the taints package test coverage has become 100%

$ go test -cover ./pkg/util/taints
ok      k8s.io/kubernetes/pkg/util/taints       1.141s  coverage: 100.0% of statements

[oomichi]

PR #112436 has been merged, and the taints package test coverage has become 100%

$ go test -cover ./pkg/util/taints
ok      k8s.io/kubernetes/pkg/util/taints       1.141s  coverage: 100.0% of statements

Thanks for separating the pull request. This new one seems simpler than the previous one.
The unit-test coverage improvement is nice anyways :-)

/lgtm

[aojea]

just a nit, lgtm

/assign @liggitt
for approval

[liggitt]

/approve

[liggitt]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: liggitt, mengjiao-liu

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