Rantly - Towards improving shrinking

property_with_shrink_test.rb

require 'test_helper'
require 'rantly/shrinks'
require 'rantly/testunit_extensions'

class PropertyShrinking < Test::Unit::TestCase
  def setup
    Rantly.gen.reset
  end

  should "be able to shrink an array of ints towards smaller int elements" do
    property_of {
      array { positive_integer }
    }.check { |arr|
      assert arr.all? { |i| i == 0 }
    }
  end
end

towards_smaller_int_elements_current

> ruby -Itest test/property_with_shrink_test.rb -n "/shrink an array of ints towards smaller int elements/"

# current shrink output
# ========================

failure: 0 tests, on:
[1453699108680333782, 1619720976417280257, 1182423061134533425, 1641371618241291156, 1118829741216353398, 2295738168544629080]
found a reduced failure case:
[726849554340166890, 1619720976417280257, 1182423061134533425, 1641371618241291156, 1118829741216353398, 2295738168544629080]
found a reduced failure case:
[363424777170083444, 1619720976417280257, 1182423061134533425, 1641371618241291156, 1118829741216353398, 2295738168544629080]
...
found a reduced failure case:
[1290, 1619720976417280257, 1182423061134533425, 1641371618241291156, 1118829741216353398, 2295738168544629080]
...
found a reduced failure case:
[0, 0, 0, 0, 15898, 2295738168544629080]
...
found a reduced failure case:
[0, 0, 0, 0, 0, 1]
found a reduced success:
[0, 0, 0, 0, 0, 0]
minimal failed data is:
[0, 0, 0, 0, 0, 1]

  1) Failure:
RantlyTest::Shrinking#test_: Rantly::Shrinking should be able to shrink an array of ints towards smaller int elements.  [test/property_with_shrink_test.rb:26]:
Failed assertion, no message given.

towards_smaller_int_elements_desired

> ruby -Itest test/property_with_shrink_test.rb -n "/shrink an array of ints towards smaller int elements/"

# desired shrink output
# ========================

failure: 0 tests, on:
[1453699108680333782, 1619720976417280257, 1182423061134533425, 1641371618241291156, 1118829741216353398, 2295738168544629080]
found a reduced failure case:
[1619720976417280257, 1182423061134533425, 1641371618241291156, 1118829741216353398, 2295738168544629080]
found a reduced failure case:
[1182423061134533425, 1641371618241291156, 1118829741216353398, 2295738168544629080]
found a reduced failure case:
[1641371618241291156, 1118829741216353398, 2295738168544629080]
found a reduced failure case:
[1118829741216353398, 2295738168544629080]
found a reduced success:
[2295738168544629080]
found a reduced failure case:
[214882974121635, 2295738168544629080]
found a reduced failure case:
[6153297412, 2295738168544629080]
...
found a reduced failure case:
[57, 435]
...
found a reduced failure case:
[1]
found a reduced success:
[0]
minimal failed data is:
[1]

  1) Failure:
RantlyTest::Shrinking#test_: Rantly::Shrinking should be able to shrink an array of ints towards smaller int elements.  [test/property_with_shrink_test.rb:26]:
Failed assertion. First failure:
[1507395846795238915, 2272427556804198336, -338939259755974401, -935990783988399133, 857239857720980257, -1756669130252341556]

Smallest shrunk failure:
[0,0]

Reduced shrunk success:
[0]

towards_smaller_int_elements_desired2

> ruby -Itest test/property_with_shrink_test.rb -n "/shrink an array of ints towards smaller int elements/"

# desired shrink output
# ========================

failure: 0 tests, on:
[2, 1]
found a reduced failure case:
[1]
found a reduced success:
[0]
minimal failed data is:
[1]

  1) Failure:
RantlyTest::Shrinking#test_: Rantly::Shrinking should be able to shrink an array of ints towards smaller int elements.  [test/property_with_shrink_test.rb:26]:
Failed assertion. First failure:
[2, 1]

Smallest:
[1]

Reduced shrunk success:
[0]

towards_smaller_int_test_check.clj

(use 'clojure.test)
(require '[clojure.test.check :as tc]
         '[clojure.test.check.generators :as gen]
         '[clojure.test.check.clojure-test :as ct :refer (defspec)]
         '[clojure.test.check.properties :as prop])

(defspec int-vec-is-all-zero
  (prop/for-all [v (gen/vector gen/pos-int)]
                (is (every? zero? v))))

(int-vec-is-all-zero)

;; OUTPUT

"""
FAIL in clojure.lang.PersistentList$EmptyList@1 (form-init8374541921464517868.clj:3)
expected: (every? zero? v)
  actual: (not
           (every?
            #<core$zero_QMARK_ clojure.core$zero_QMARK_@28164824>
            [1 0]))

FAIL in clojure.lang.PersistentList$EmptyList@1 (form-init8374541921464517868.clj:3)
expected: (every? zero? v)
  actual: (not
           (every?
            #<core$zero_QMARK_ clojure.core$zero_QMARK_@28164824>
            [1]))
{:result false, :seed 1417441962891, :failing-size 2, :num-tests 3, :fail [[1 0]], :shrunk {:total-nodes-visited 4, :depth 1, :result false, :smallest [[1]]}}
"""