pkg/mock, pkg/lightning: unify mock files (#786)

[ti-srebot]

cherry-pick #786 to release-4.0
You can switch your code base to this Pull Request by using git-extras:

# In br repo:
git pr https://github.com/pingcap/br/pull/788

After apply modifications, you can push your change to this PR via:

git push git@github.com:ti-srebot/br.git pr/788:release-4.0-f1daf8a4d6d1

---

What problem does this PR solve?

Unify mock files of BR and Lightning.

Check List

Tests

• Unit test
• Integration test

Code changes

• Has exported function/method change
• Has exported variable/fields change
• Has interface methods change

Related changes

• Need to cherry-pick to the release branch

Release Note

• No release note.

[overvenus]

/run-all-tests

[glorv]

/lgtm

[overvenus]

Test build fails @kennytm

[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:724:17: undefined: "github.com/pingcap/br/pkg/mock".NewMockBackend
[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:756:17: undefined: "github.com/pingcap/br/pkg/mock".NewMockBackend
[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:832:17: undefined: "github.com/pingcap/br/pkg/mock".NewMockBackend
[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:837:16: undefined: "github.com/pingcap/br/pkg/mock".NewMockEngineWriter
[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:872:17: undefined: "github.com/pingcap/br/pkg/mock".NewMockBackend
[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:877:16: undefined: "github.com/pingcap/br/pkg/mock".NewMockEngineWriter
[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:1087:16: undefined: "github.com/pingcap/br/pkg/mock".NewMockImportKVClient
[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:1088:20: undefined: "github.com/pingcap/br/pkg/mock".NewMockImportKV_WriteEngineClient
[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:1089:21: undefined: "github.com/pingcap/br/pkg/mock".NewMockImportKV_WriteEngineClient
[2021-03-10T18:14:09.282Z] pkg/lightning/restore/restore_test.go:1192:17: undefined: "github.com/pingcap/br/pkg/mock".NewMockBackend

[kennytm]

let's hold this off until the tikv-client people actually confirmed the working solution.

[kennytm]

(the #838 cherry-pick has been reverted.)

[kennytm]

/lgtm

[ti-chi-bot]

[REVIEW NOTIFICATION]

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• kennytm

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[glorv]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Details

Commit hash: a2c6ff4

[glorv]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Details

Commit hash: 0c8ca98