It is unnecessary to create a new formatter for each test.
("test smell": General Fixture / Test Code Duplication)

renamed UnicodeConverterTest to UnicodeConverterFormatterTest

It is unnecessary to create a new formatter for each test.
("test smell": General Fixture / Test Code Duplication)

It is unnecessary to create a new formatter for each test.
("test smell": General Fixture / Test Code Duplication)

It is unnecessary to create a new comparator before each test and setting it to null after each test.
("test smell": General Fixture / Test Code Duplication)

test code quality improvement
("test smell": Test Code Duplication)
easier to maintain, less risk of error propagation.

- remove unmeaningful comment
- testSpecialBracketPlacement
- add disabled for commented code
- integrate assertion in testPurify