JUnit Internals

This chapter goes through an example of cleaning up a Java class, JUnit ComparisonCompacter.

Some examples of improvements:

• Extracting boolean statements to function to clarify their MEANING/INTENT
  • E.g.

        if (expected == null || actual == null || stringsAreEqual()) {
            ...
    

    to

        if (shouldNotCompact()) {
            ...
        bool shouldNotCompact() {
            return expected == null || actual == null || stringsAreEqual();
        }
    

• clarifying function names to expose side effects/actions besides just what the name implies
  • E.g.

        String compact() {
        ...
    

    to

        String formatCompactedComparison() {
        ...
    

• clarifying/renaming variable names
  • E.g. changing suffixIndex to suffixLength
• Extracting error handling/checks from the logic/flow of a function

Follow the Boy Scout Rule - always leave code cleaner than you found it.