[FLINK-13258] Add tests for LongHashPartition, StringCallGen and EqualiserCodeGenerator

[tsreaper]

What is the purpose of the change

This PR adds tests for LongHashPartition, StringCallGen and EqualiserCodeGenerator as these classes have no tests currently.

Brief change log

• Add tests for LongHashPartition
• Add tests for StringCallGen
• Add tests for EqualiserCodeGenerator

Verifying this change

This change added tests and can be verified as follows: Run LongHashPartitionTest, StringCallGenTest and EqualiserCodeGeneratorTest.

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): no
• The public API, i.e., is any changed class annotated with @Public(Evolving): no
• The serializers: no
• The runtime per-record code paths (performance sensitive): no
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Yarn/Mesos, ZooKeeper: no
• The S3 file system connector: no

Documentation

• Does this pull request introduce a new feature? no
• If yes, how is the feature documented? not applicable

[flinkbot]

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Automated Checks

Last check on commit 8afec12 (Tue Aug 06 15:43:41 UTC 2019)

Warnings:

• No documentation files were touched! Remember to keep the Flink docs up to date!

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Review Progress

• ❓ 1. The [description] looks good.
• ❓ 2. There is [consensus] that the contribution should go into to Flink.
• ❓ 3. Needs [attention] from.
• ❓ 4. The change fits into the overall [architecture].
• ❓ 5. Overall code [quality] is good.

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Details

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[flinkbot]

CI report:

• 26f95bf : FAILURE Build
• 8afec12 : FAILURE Build

[tsreaper]

Travis: https://travis-ci.com/TsReaper/flink/builds/119120737

[flinkbot]

CI report:

• 8afec12 UNKNOWN

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[github-actions]

This PR is being marked as stale since it has not had any activity in the last 180 days.
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[github-actions]

This PR has been closed since it has not had any activity in 120 days.
If you feel like this was a mistake, or you would like to continue working on it,
please feel free to re-open the PR and ask for a review.