Github user sunjincheng121 commented on the issue:
https://github.com/apache/flink/pull/3943
**I once again seriously consider the Refactoring work, according to the
following principles updated the PR.**
  **First, the test type and purpose(4 types):**
* Unit Test: to ensure the correctness of the most granular features
* StringExpression Test: Verify the consistency of java and scalaAPI
* Validation Test: Check the API exception information
* Integration Test: Integration testing, verifying runtime and end-to-end
correctness
  **Second, the directory structure(folders) and purpose:**
 Â
 The TEST directory contains all the paths (folders) of the SRC
directory - the functional tests included three type test case (**Unit Test**,
**StringExpression Test**,**Validation Test**)
  **Note:** runtime directory contains both runtime (**Unit Test**,
**StringExpression Test**,**Validation Test**), and All table API/SQL
**Integration Test**.
  **Third, the file name naming convention:**
* Unit Test -> functionName + **Test**
* StringExpression Test -> functionName + **StringExpressionTest**
* Validation Test -> functionName + **ValidationTest**
* Integration Test -> FunctionName + **ITCase**
**After the change of the directory structure, as shown below:**
@twalthr @fhueske @wuchong The change is big, so I need your help to ensure
that the direction of change is correct.
Best,
SunJincheng
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
