rspec: match_array は 多次元配列の順番を検証してしまう ref: http://qiita.com/Yinaura/items/e20fbfee18e34c195f85

file0.txt

expect([1,2]).to match_array [2,1] # => true

file1.txt

expect([[1,2],[3,4]]).to match_array [[2,1],[4,3]] # => false

file2.txt

expect([[1,2],[3,4]]).to match_array [[3,4],[1,2]] # => true

file3.txt

expect([1,2]).to match_array [2,1] # => true
expect([3,4]).to match_array [4,3] # => true