mu

test/test_helper.rb

@@ -1,5 +1,7 @@
 require "minitest/autorun"
 
+require "digest"
+
 module Minitest
 
   class Property < Test
@@ -297,7 +299,7 @@ module Minitest
     # You can safely omit implementing this at the cost of somewhat increased
     # shrinking time.
     class CachedTestFunction
-      def init(&test_function)
+      def initialize(&test_function)
         @test_function = test_function
 
         # Tree nodes are either a point at which a choice occurs
@@ -320,53 +322,44 @@ module Minitest
             node = node.fetch(c)
             # mark_status was called, thus future choices
             # will be ignored.
-            # if isinstance(node, Status):
-            #     assert node != Status.OVERRUN
-            #     return node
+            if node.is_a?(Status)
+              fail if node == Status::OVERRUN
+              return node
+            end
           end
+          # If we never entered an unknown region of the tree
+          # or hit a Status value, then we know that another
+          # choice will be made next and the result will overrun.
+          return Status::OVERRUN
         rescue KeyError
         end
+
+        # We now have to actually call the test function to find out what
+        # happens.
+        test_case = TestCase.for_choices(choices)
+        @test_function.(test_case)
+        fail if test_case.status.nil?
+
+        # We enter the choices made in a tree.
+        node = @tree
+        test_case.choices.each.with_index do |c, i|
+          if i + 1 < test_case.choices.length || test_case.status == Status::OVERRUN
+            if node.has_key?(c)
+              node = node[c]
+            else
+              node = node[c] = {}
+            end
+          else
+            node[c] = test_case.status
+          end
         end
 
-      # def __call__(self, choices: Sequence[int]) -> Status:
-      #     # XXX The type of node is problematic
-      #     node: Any = self.tree
-      #     try:
-      #         for c in choices:
-      #             node = node[c]
-      #             # mark_status was called, thus future choices
-      #             # will be ignored.
-      #             if isinstance(node, Status):
-      #                 assert node != Status.OVERRUN
-      #                 return node
-      #         # If we never entered an unknown region of the tree
-      #         # or hit a Status value, then we know that another
-      #         # choice will be made next and the result will overrun.
-      #         return Status.OVERRUN
-      #     except KeyError:
-      #         pass
-
-      #     # We now have to actually call the test function to find out
-      #     # what happens.
-      #     test_case = TestCase.for_choices(choices)
-      #     self.test_function(test_case)
-      #     assert test_case.status is not None
-
-      #     # We enter the choices made in a tree.
-      #     node = self.tree
-      #     for i, c in enumerate(test_case.choices):
-      #         if i + 1 < len(test_case.choices) or test_case.status == Status.OVERRUN:
-      #             try:
-      #                 node = node[c]
-      #             except KeyError:
-      #                 node = node.setdefault(c, {})
-      #         else:
-      #             node[c] = test_case.status
-      #     return test_case.status
+        test_case.status
+      end
     end
 
     class TestingState
-      attr_reader :result, :valid_test_cases
+      attr_reader :result, :valid_test_cases, :calls
 
       def initialize(random:, test_function:, max_examples:)
         @random, @_test_function, @max_examples = random, test_function, max_examples
@@ -506,16 +499,12 @@ module Minitest
         # reevaluating it in those cases. This also allows us to catch cases
         # where we try something that is e.g. a prefix of something we've
         # previously tried, which is guaranteed not to work.
-        # cached = CachedTestFunction(self.test_function)
+        cached = CachedTestFunction.new {|tc| test_function(tc) }
 
-        # def consider(choices: array[int]) -> bool:
-        #     if choices == self.result:
-        #         return True
-        #     return cached(choices) == Status.INTERESTING
         consider = ->(choices) do
           return true if choices == @result
 
-          test_function(TestCase.for_choices(choices)) == Status::INTERESTING
+          cached.(choices) == Status::INTERESTING
         end
 
         fail unless consider.(@result)
@@ -714,7 +703,28 @@ module Minitest
     end
 
     class DirectoryDb
-      def initialize(directory)
+      def initialize(dir)
+        @dir = dir
+        Dir.mkdir(@dir)
+      rescue SystemCallError => e
+        raise unless e.errno == Errno::EEXIST::Errno
+      end
+
+      def [](key)
+        f = file(key)
+        return nil unless File.exist?(f)
+
+        File.read(f)
+      end
+
+      def []=(key, value)
+        File.write(file(key), value)
+      end
+
+      private
+
+      def file(key)
+        File.join(@dir, Digest::SHA1.hexdigest(key)[0...10])
       end
     end
 
@@ -727,18 +737,24 @@ module Minitest
     # Raised when a test has no valid examples.
     class Unsatisfiable < StandardError; end
 
-    module Status
+    class Status < Struct.new(:value)
       # Test case didn't have enough data to complete
-      OVERRUN = 0
+      OVERRUN = self.new(0)
 
       # Test case contained something that prevented completion
-      INVALID = 1
+      INVALID = self.new(1)
 
       # Test case completed just fine but was boring
-      VALID = 2
+      VALID = self.new(2)
 
       # Test case completed and was interesting
-      INTERESTING = 3
+      INTERESTING = self.new(3)
+
+      include Comparable
+
+      def <=>(other)
+        value <=> other.value
+      end
     end
   end
 end
@@ -812,9 +828,31 @@ class TestProperty < Minitest::Property
     OUT
   end
 
-  # def test_reuses_results_from_the_database(tmpdir):
-  #     db = DirectoryDB(tmpdir)
-  #     count = 0
+  def test_reuses_results_from_the_database
+    Dir.mktmpdir do |tmpdir|
+      db = DirectoryDb.new(tmpdir)
+      count = 0
+
+      run = -> {
+        assert_raises(Minitest::Assertion) do
+          run_test("reuses_results_from_the_database", database: db, quiet: true) do |test_case|
+            count += 1
+            assert test_case.choice(10_000) < 10
+          end
+        end
+      }
+
+      run.()
+
+      assert_equal 1, Dir.children(tmpdir).length
+      prev_count = count
+
+      run.()
+
+      assert_equal 1, Dir.children(tmpdir).length
+      assert_equal prev_count + 2, count
+    end
+  end
 
   #     def run():
   #         with pytest.raises(AssertionError):
@@ -853,9 +891,10 @@ class TestProperty < Minitest::Property
   end
 
   def test_error_on_unbounded_test_function
-    # TODO Make the warnings go away
     orig_buffer_size = Minitest::Property::BUFFER_SIZE
+    suppress_warnings do
       Minitest::Property.const_set(:BUFFER_SIZE, 10)
+    end
 
     assert_raises(Unsatisfiable) do
       run_test("error_on_unbounded_test_function", database: {}, max_examples: 5) do |test_case|
@@ -865,27 +904,28 @@ class TestProperty < Minitest::Property
       end
     end
   ensure
+    suppress_warnings do
       Minitest::Property.const_set(:BUFFER_SIZE, orig_buffer_size)
     end
+  end
 
-  # def test_function_cache():
-  #     def tf(tc):
-  #         if tc.choice(1000) >= 200:
-  #             tc.mark_status(Status.INTERESTING)
-  #         if tc.choice(1) == 0:
-  #             tc.reject()
-
-  #     state = State(Random(0), tf, 100)
+  def test_function_cache
+    tf = ->(tc) do
+      tc.mark_status(Status::INTERESTING) if tc.choice(1_000) >= 200
+      tc.reject if tc.choice(1).zero?
+    end
 
-  #     cache = CachedTestFunction(state.test_function)
+    state = TestingState.new(random: Random.new(0), test_function: tf, max_examples: 100)
+    cache = CachedTestFunction.new {|tc| state.test_function(tc) }
 
-  #     assert cache([1, 1]) == Status.VALID
-  #     assert cache([1]) == Status.OVERRUN
-  #     assert cache([1000]) == Status.INTERESTING
-  #     assert cache([1000]) == Status.INTERESTING
-  #     assert cache([1000, 1]) == Status.INTERESTING
+    assert_equal Status::VALID, cache.([1, 1])
+    assert_equal Status::OVERRUN, cache.([1])
+    assert_equal Status::INTERESTING, cache.([1_000])
+    assert_equal Status::INTERESTING, cache.([1_000])
+    assert_equal Status::INTERESTING, cache.([1_000, 1])
 
-  #     assert state.calls == 2
+    assert_equal 2, state.calls
+  end
 
   # Targeting has a number of places it checks for whether we've exceeded the
   # generation limits. This makes sure we've checked them all.
@@ -1205,4 +1245,13 @@ class TestProperty < Minitest::Property
       end
     end
   end
+
+  private
+
+  def suppress_warnings
+    original_verbosity = $VERBOSE
+    $VERBOSE = nil
+    yield
+    $VERBOSE = original_verbosity
+  end
 end