Update tests

Author: jiahao

test/permutations.jl

@@ -1,21 +1,7 @@
 using Combinatorics
 using Base.Test
 
-import Combinatorics: ipermute!, isperm, levicivita, nthperm, nthperm!, parity, permutations, permute!
-
-p = shuffle([1:1000;])
-@test isperm(p)
-
-push!(p, 1)
-@test !isperm(p)
-
-a = randcycle(10)
-@test ipermute!(permute!([1:10;], a),a) == [1:10;]
-
-# PR 12785
-let a = 2:-1:1
-    @test ipermute!(permute!([1, 2], a), a) == [1, 2]
-end
+import Combinatorics: levicivita, nthperm, nthperm!, parity, permutations
 
 @test collect(permutations("abc")) == Any[['a','b','c'],['a','c','b'],['b','a','c'],
                                           ['b','c','a'],['c','a','b'],['c','b','a']]