fix: Label handling

[embano1]

Follow-up on #194 where the logic was still not correct in all cases. The behavior is now as expected: if --labels is specified all keys and values specified must match a feature. This allows for arbitrary and complex combinations of multiple features within one suite.

For example:

f1 := features.New("label demo 1").
		WithLabel("a", "1").
		WithLabel("all", "true").
		Feature()

f2 := features.New("label demo 2").
		WithLabel("all", "true").
		Feature()

f3 := features.New("label demo 3").
		WithLabel("a", "2").
		WithLabel("all", "true").
		Feature()

f4 := features.New("label demo 4").
		WithLabel("a", "1").
		WithLabel("b", "1").
		WithLabel("all", "true").
		Feature()

Leads to the following outcomes with different --labels:

go test -race -v ./e2e -args -v 4 --labels=some=value
--- PASS: TestDemoE2E (0.07s)
    --- SKIP: TestDemoE2E/label_demo_1 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_2 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_3 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_4 (0.00s)
PASS

go test -race -v ./e2e -args -v 4 --labels=a=1
--- PASS: TestDemoE2E (0.06s)
    --- PASS: TestDemoE2E/label_demo_1 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_2 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_3 (0.00s)
    --- PASS: TestDemoE2E/label_demo_4 (0.00s)
PASS

go test -race -v ./e2e -args -v 4 --labels=all=true
--- PASS: TestDemoE2E (0.05s)
    --- PASS: TestDemoE2E/label_demo_1 (0.00s)
    --- PASS: TestDemoE2E/label_demo_2 (0.00s)
    --- PASS: TestDemoE2E/label_demo_3 (0.00s)
    --- PASS: TestDemoE2E/label_demo_4 (0.00s)
PASS

go test -race -v ./e2e -args -v 4 --labels=all=true,a=1
--- PASS: TestDemoE2E (0.04s)
    --- PASS: TestDemoE2E/label_demo_1 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_2 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_3 (0.00s)
    --- PASS: TestDemoE2E/label_demo_4 (0.00s)
PASS

Passing no --labels of course works as expected

go test -race -v ./e2e -args -v 4
--- PASS: TestDemoE2E (0.06s)
    --- PASS: TestDemoE2E/label_demo_1 (0.00s)
    --- PASS: TestDemoE2E/label_demo_2 (0.00s)
    --- PASS: TestDemoE2E/label_demo_3 (0.00s)
    --- PASS: TestDemoE2E/label_demo_4 (0.00s)
PASS

Also works in combination with --skip-labels

go test -race -v ./e2e -args -v 4 --labels=a=1 --skip-labels=all=true
--- PASS: TestDemoE2E (0.05s)
    --- SKIP: TestDemoE2E/label_demo_1 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_2 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_3 (0.00s)
    --- SKIP: TestDemoE2E/label_demo_4 (0.00s)
PASS

[k8s-ci-robot]

Hi @embano1. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[vladimirvivien]

@embano1 This looks great. Thanks for the awesome work.

I will ask for one favor though:
Can you update examples/skip_flags/README.md with the examples you have on the PR that shows the complex combination that is now supported!

[embano1]

@vladimirvivien done! Formatted and added more details to the README for clarity. Also updated the test examples to show how multiple labels can be used.

[ShwethaKumbla]

/ok-to-test

[vladimirvivien]

Thanks a lot for this and the doc update.
Leaving it as comment for now so you can see my comment on the review.

/lgtm

[vladimirvivien]

I support this removal.
But we probably need to put it in its own doc (i.e. docs/supported_flags.md).
Maybe for now, open a new issue to have proper argument documentations.

[embano1]

The reason I removed it as we have this already covered in the flags example and this one is focused on labels. But will add tracking issue.

[vladimirvivien]

Ok, if already documented, no need for the tracking issue.

[embano1]

@vladimirvivien tide is still pending?

[vladimirvivien]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: embano1, vladimirvivien

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