balancergroup: merge whitebox tests into blackbox test

[hugehoo]

fixes #8996

• this PR covers test isolation in internal/balancergroup packages
• merges white box test (balancergroup/balancergroup_test.go) into black box test (balancergroup/balancergroup_ext_test.go) to ensure to test the API, not the internal symbols.
  • moved 16 tests from balancergroup_test.go to balancergroup_ext_test.go
• no production code changed

RELEASE NOTES: N/A

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.02%. Comparing base (3d82ab3) to head (88ac5b6).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #9094      +/-   ##
==========================================
- Coverage   83.08%   83.02%   -0.07%     
==========================================
  Files         413      413              
  Lines       33484    33484              
==========================================
- Hits        27821    27799      -22     
- Misses       4240     4250      +10     
- Partials     1423     1435      +12     

see 19 files with indirect coverage changes

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[Pranjali-2501]

Hi @hugehoo, Thanks for raising the PR.

Instead of creating a new file and copy the content, can you please use git mv to move the file and then update the package name to a test only package.

[hugehoo]

Hi @hugehoo, Thanks for raising the PR.

Instead of creating a new file and copy the content, can you please use git mv to move the file and then update the package name to a test only package.

thanks for the comment, didn't know such a mechanism.
applied on 42d8fab

[easwars]

If you are simply moving the tests from one file to another and changing the package name, why is the diff still so huge? I'm not entirely convinced whether the git mv was done appropriately.

[hugehoo]

@easwars the git mv is meaningless in this case because balancergroup_ext_test.go already exists on master. Git can detect a rename when the target file doesn't exist but since it does, git recognizes this as:

• balancergroup_test.go: entire file deleted (847 lines)
• balancergroup_ext_test.go: modified from 124 lines to ~930 lines

No matter how I re-structure the commits, the "Files changed" will show the same large diff, i guess.

---

Although It would still get a large diff, I could reset current commits and restructure 3 small commits to make it easier to review.

  1. Consolidate ext_test into balancergroup_test.go (+82 / -124): moves TestBalancerGroup_RemoveImmediately into the
  whitebox test file and deletes balancergroup_ext_test.go
  2. Rename test file (0 lines changed): pure git mv, detected as R100
  3. Convert to blackbox (+18 / -17): mechanical changes — package name, import, and balancergroup. prefix

[easwars]

@hugehoo : Sorry, I didnt realize that the file existed already. But feel free to create a new file, so that the diff only ends up showing the lines that are actually changed.

[hugehoo]

@easwars thanks for comments!
I removed the balancergroup_ext_test.go and updated whitebox balancegroup_test.go to blackbox.
Moved the blackbox tests(balancergroup_ext_test.go) into balancegroup_test.go too. So the file name haven't changed and git diff only shows where actually changed.
88ac5b6