Unit tests for LeaseTaskList

[jakobht]

What changed?

• Unit tests for LeaseTaskList
• Added types for constants to avoid manual conversion in tests
• Fixed but where the wrong error was returned

Why?
Increase coverage

How did you test it?

Potential risks

Release notes

Documentation Changes

[3vilhamster]

I think it would be easier to read this as a table test:

for _, tc := []struct{
   name string
   prepareDB(*db.Mock)
   assertError func(t *testing.T, err error)
   assertResult func(t * testing.T, res)
}

It would be easier to assess if all possible cases are covered, and it should be easier to read.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 67.68%. Comparing base (96c47bc) to head (cfb5799).
Report is 1 commits behind head on master.

Additional details and impacted files

Files	Coverage Δ
common/persistence/nosql/nosql_task_store.go	43.82% <100.00%> (+24.25%)	⬆️

... and 8 files with indirect coverage changes

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[3vilhamster]

LGTM, though I suggest moving helpers down the file.
But this is more of a nit style opinion

[coveralls]

Pull Request Test Coverage Report for Build 018fa9e9-e31c-40b5-97ac-941c9c147468

Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• 55 unchanged lines in 18 files lost coverage.
• Overall coverage decreased (-0.01%) to 69.42%

---

Files with Coverage Reduction	New Missed Lines	%
service/history/task/transfer_standby_task_executor.go	2	86.21%
common/task/weighted_round_robin_task_scheduler.go	2	88.06%
common/task/parallel_task_processor.go	2	93.06%
service/matching/tasklist/db.go	2	73.23%
common/peerprovider/ringpopprovider/config.go	2	81.58%
service/matching/tasklist/task_list_manager.go	2	76.48%
common/persistence/sql/sqlplugin/mysql/task.go	2	73.68%
service/history/execution/mutable_state_util.go	2	78.52%
common/membership/hashring.go	2	84.69%
common/persistence/sql/sqlplugin/mysql/db.go	2	79.49%

Totals
Change from base Build 018fa9d1-f951-43c8-8e3e-3538fa7befdb:	-0.01%
Covered Lines:	102338
Relevant Lines:	147418

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💛 - Coveralls