test: Simplify the function that skips integration tests

[alexandear]

This PR refactors integration tests:

• Refactor checkAuth function in by passing *testing.T parameter and renaming for clarity.
• Simplifying client and auth initialization by using sync.OnceValues.
• Fix TestAPIMeta which fails if run without OAuth token.

Running integration tests locally

TestAPIMeta without token:

❯ go test -tags=integration -count=1 -v -run=TestAPIMeta ./test/integration/...=== RUN TestAPIMeta--- PASS: TestAPIMeta (0.28s)PASSok github.com/google/go-github/v75/test/integration 0.860s

TestAPIMeta with token:

❯ GITHUB_AUTH_TOKEN=ghp_... go test -tags=integration -count=1 -v -run=TestAPIMeta ./test/integration/...=== RUN TestAPIMeta--- PASS: TestAPIMeta (0.28s)PASSok github.com/google/go-github/v75/test/integration 0.860s

All tests without token:

❯ go test -tags=integration -count=1 -v ./test/integration/...=== RUN TestActivity_Starring github_test.go:34: No OAuth token - skipping portions of TestActivity_Starring--- SKIP: TestActivity_Starring (0.30s)=== RUN TestActivity_Watching github_test.go:34: No OAuth token - skipping portions of TestActivity_Watching--- SKIP: TestActivity_Watching (0.20s)=== RUN TestOrganizationAuditLog github_test.go:34: No OAuth token - skipping portions of TestOrganizationAuditLog--- SKIP: TestOrganizationAuditLog (0.00s)=== RUN TestAuthorizationsAppOperations authorizations_test.go:130: Skipping test because the required environment variable (GITHUB_CLIENT_ID) is not present.--- SKIP: TestAuthorizationsAppOperations (0.00s)=== RUN TestIssueEvents--- PASS: TestIssueEvents (1.06s)=== RUN TestEmojis--- PASS: TestEmojis (0.17s)=== RUN TestAPIMeta--- PASS: TestAPIMeta (0.16s)=== RUN TestRateLimits--- PASS: TestRateLimits (0.04s)=== RUN TestPullRequests_ListCommits--- PASS: TestPullRequests_ListCommits (0.26s)=== RUN TestRepositories_CRUD github_test.go:34: No OAuth token - skipping portions of TestRepositories_CRUD--- SKIP: TestRepositories_CRUD (0.00s)=== RUN TestRepositories_BranchesTags--- PASS: TestRepositories_BranchesTags (0.65s)=== RUN TestRepositories_EditBranches github_test.go:34: No OAuth token - skipping portions of TestRepositories_EditBranches--- SKIP: TestRepositories_EditBranches (0.00s)=== RUN TestRepositories_ListByAuthenticatedUser github_test.go:34: No OAuth token - skipping portions of TestRepositories_ListByAuthenticatedUser--- SKIP: TestRepositories_ListByAuthenticatedUser (0.00s)=== RUN TestRepositories_ListByUser--- PASS: TestRepositories_ListByUser (0.65s)=== RUN TestRepositories_DownloadReleaseAsset github_test.go:34: No OAuth token - skipping portions of TestRepositories_DownloadReleaseAsset--- SKIP: TestRepositories_DownloadReleaseAsset (0.00s)=== RUN TestRepositories_Autolinks github_test.go:34: No OAuth token - skipping portions of TestRepositories_Autolinks--- SKIP: TestRepositories_Autolinks (0.00s)=== RUN TestUsers_Get--- PASS: TestUsers_Get (0.34s)=== RUN TestUsers_Update github_test.go:34: No OAuth token - skipping portions of TestUsers_Update--- SKIP: TestUsers_Update (0.00s)=== RUN TestUsers_Emails github_test.go:34: No OAuth token - skipping portions of TestUsers_Emails--- SKIP: TestUsers_Emails (0.00s)=== RUN TestUsers_Keys github_test.go:34: No OAuth token - skipping portions of TestUsers_Keys--- SKIP: TestUsers_Keys (0.16s)PASSok github.com/google/go-github/v75/test/integration 4.347s

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.11%. Comparing base (233fe03) to head (9c77662).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@ Coverage Diff @@## master #3752 +/- ##
=======================================
Coverage 91.11% 91.11% =======================================
Files 187 187 Lines 16702 16702 =======================================
Hits 15218 15218 Misses 1296 1296 Partials 188 188 

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[gmlewis]

What's the story with the complete reversal on this one?
Do we need to add a comment? Or was it just plain broken?

[alexandear]

verifiable_password_authentication is false for github.com since February 14, 2020. So yeah, the test seems broken for 4.5 years.

I found this information on:

• https://developer.github.com/changes/2020-02-14-deprecating-password-auth/
• https://developer.github.com/changes/2020-02-14-deprecating-oauth-auth-endpoint/
• GitHub Desktop authentication primarily through browser flow desktop/desktop#9231
• https://docs2.lfe.io/v3/meta/#:~:text=GitHub%20Enterprise%20instances%20using%20CAS%20or%20OAuth%20for%20authentication%20will%20return%20false

[alexandear]

@gmlewis I can remove this check at all:

if*meta.VerifiablePasswordAuthentication {
t.Error("APIMeta VerifiablePasswordAuthentication is true")
}

The test will still be valuable.

[gmlewis]

That's OK. We can leave it as it will be good-to-know for people who were not aware of the change in 2020.

Thank you, @alexandear!

[gmlewis]

Thank you, @alexandear!
LGTM.
Merging.