delete all code and test
empty word list and any word
TPP: {} -> nil, nil -> constant
one character word list and input is double of this character
TPP: unconditional -> if
one word list and input is double of this word
TPP: constant -> scalar
one word list and input has no anagram
TPP: statement -> statements
one word list and input has double characters of this word with different order
TPP: expression -> function
With current test and code, if we try to introduce the "wordList.head" as a parameter of methed isAnagram, the Intellij IDE will let the refactoring happen, but will fail the test
The reason of failing the test is that the "wordList.head" is now calculated before the "!wordList.isEmpty" check
I feel that it's hard to avoid doing a wrong refactoring in such case since it's hard to know there is a pre-check must happen before introducing the parameter
more than one word list and input only is double of non first word
TPP: to functional style
two word list and input is combination of these two words
TPP: unconditional -> if
more than one word list and input only is combination of any two words
TPP: expression -> function, add two word anagram logic into the original functional style code
acceptance test and code refactoring