Use assert_predicate and assert_not_predicate

19 files changed, 361 insertions, 361 deletions

diff --git a/activemodel/test/cases/attribute_set_test.rb b/activemodel/test/cases/attribute_set_test.rb
index 6e522d6c80..9f7498fa65 100644
--- a/activemodel/test/cases/attribute_set_test.rb
+++ b/activemodel/test/cases/attribute_set_test.rb
@@ -74,8 +74,8 @@ module ActiveModel
 
       clone.freeze
 
-      assert clone.frozen?
-      assert_not attributes.frozen?
+      assert_predicate clone, :frozen?
+      assert_not_predicate attributes, :frozen?
     end
 
     test "to_hash returns a hash of the type cast values" do
@@ -105,8 +105,8 @@ module ActiveModel
 
     test "known columns are built with uninitialized attributes" do
       attributes = attributes_with_uninitialized_key
-      assert attributes[:foo].initialized?
-      assert_not attributes[:bar].initialized?
+      assert_predicate attributes[:foo], :initialized?
+      assert_not_predicate attributes[:bar], :initialized?
     end
 
     test "uninitialized attributes are not included in the attributes hash" do
@@ -169,7 +169,7 @@ module ActiveModel
 
       assert attributes.key?(:foo)
       assert_equal [:foo], attributes.keys
-      assert attributes[:foo].initialized?
+      assert_predicate attributes[:foo], :initialized?
     end
 
     class MyType
diff --git a/activemodel/test/cases/attribute_test.rb b/activemodel/test/cases/attribute_test.rb
index 47ca495a01..ea2b0efd11 100644
--- a/activemodel/test/cases/attribute_test.rb
+++ b/activemodel/test/cases/attribute_test.rb
@@ -175,33 +175,33 @@ module ActiveModel
 
     test "an attribute has not been read by default" do
       attribute = Attribute.from_database(:foo, 1, Type::Value.new)
-      assert_not attribute.has_been_read?
+      assert_not_predicate attribute, :has_been_read?
     end
 
     test "an attribute has been read when its value is calculated" do
       attribute = Attribute.from_database(:foo, 1, Type::Value.new)
       attribute.value
-      assert attribute.has_been_read?
+      assert_predicate attribute, :has_been_read?
     end
 
     test "an attribute is not changed if it hasn't been assigned or mutated" do
       attribute = Attribute.from_database(:foo, 1, Type::Value.new)
 
-      assert_not attribute.changed?
+      assert_not_predicate attribute, :changed?
     end
 
     test "an attribute is changed if it's been assigned a new value" do
       attribute = Attribute.from_database(:foo, 1, Type::Value.new)
       changed = attribute.with_value_from_user(2)
 
-      assert changed.changed?
+      assert_predicate changed, :changed?
     end
 
     test "an attribute is not changed if it's assigned the same value" do
       attribute = Attribute.from_database(:foo, 1, Type::Value.new)
       unchanged = attribute.with_value_from_user(1)
 
-      assert_not unchanged.changed?
+      assert_not_predicate unchanged, :changed?
     end
 
     test "an attribute can not be mutated if it has not been read,
@@ -209,15 +209,15 @@ module ActiveModel
       type_which_raises_from_all_methods = Object.new
       attribute = Attribute.from_database(:foo, "bar", type_which_raises_from_all_methods)
 
-      assert_not attribute.changed_in_place?
+      assert_not_predicate attribute, :changed_in_place?
     end
 
     test "an attribute is changed if it has been mutated" do
       attribute = Attribute.from_database(:foo, "bar", Type::String.new)
       attribute.value << "!"
 
-      assert attribute.changed_in_place?
-      assert attribute.changed?
+      assert_predicate attribute, :changed_in_place?
+      assert_predicate attribute, :changed?
     end
 
     test "an attribute can forget its changes" do
@@ -226,7 +226,7 @@ module ActiveModel
       forgotten = changed.forgetting_assignment
 
       assert changed.changed? # sanity check
-      assert_not forgotten.changed?
+      assert_not_predicate forgotten, :changed?
     end
 
     test "with_value_from_user validates the value" do
diff --git a/activemodel/test/cases/attributes_dirty_test.rb b/activemodel/test/cases/attributes_dirty_test.rb
index 83a86371e0..c991176389 100644
--- a/activemodel/test/cases/attributes_dirty_test.rb
+++ b/activemodel/test/cases/attributes_dirty_test.rb
@@ -25,11 +25,11 @@ class AttributesDirtyTest < ActiveModel::TestCase
   end
 
   test "setting attribute will result in change" do
-    assert !@model.changed?
-    assert !@model.name_changed?
+    assert_not_predicate @model, :changed?
+    assert_not_predicate @model, :name_changed?
     @model.name = "Ringo"
-    assert @model.changed?
-    assert @model.name_changed?
+    assert_predicate @model, :changed?
+    assert_predicate @model, :name_changed?
   end
 
   test "list of changed attribute keys" do
@@ -71,35 +71,35 @@ class AttributesDirtyTest < ActiveModel::TestCase
   test "attribute mutation" do
     @model.name = "Yam"
     @model.save
-    assert !@model.name_changed?
+    assert_not_predicate @model, :name_changed?
     @model.name.replace("Hadad")
-    assert @model.name_changed?
+    assert_predicate @model, :name_changed?
   end
 
   test "resetting attribute" do
     @model.name = "Bob"
     @model.restore_name!
     assert_nil @model.name
-    assert !@model.name_changed?
+    assert_not_predicate @model, :name_changed?
   end
 
   test "setting color to same value should not result in change being recorded" do
     @model.color = "red"
-    assert @model.color_changed?
+    assert_predicate @model, :color_changed?
     @model.save
-    assert !@model.color_changed?
-    assert !@model.changed?
+    assert_not_predicate @model, :color_changed?
+    assert_not_predicate @model, :changed?
     @model.color = "red"
-    assert !@model.color_changed?
-    assert !@model.changed?
+    assert_not_predicate @model, :color_changed?
+    assert_not_predicate @model, :changed?
   end
 
   test "saving should reset model's changed status" do
     @model.name = "Alf"
-    assert @model.changed?
+    assert_predicate @model, :changed?
     @model.save
-    assert !@model.changed?
-    assert !@model.name_changed?
+    assert_not_predicate @model, :changed?
+    assert_not_predicate @model, :name_changed?
   end
 
   test "saving should preserve previous changes" do
@@ -118,7 +118,7 @@ class AttributesDirtyTest < ActiveModel::TestCase
   test "saving should preserve model's previous changed status" do
     @model.name = "Jericho Cane"
     @model.save
-    assert @model.name_previously_changed?
+    assert_predicate @model, :name_previously_changed?
   end
 
   test "previous value is preserved when changed after save" do
@@ -143,7 +143,7 @@ class AttributesDirtyTest < ActiveModel::TestCase
 
   test "using attribute_will_change! with a symbol" do
     @model.size = 1
-    assert @model.size_changed?
+    assert_predicate @model, :size_changed?
   end
 
   test "reload should reset all changes" do
@@ -170,7 +170,7 @@ class AttributesDirtyTest < ActiveModel::TestCase
 
     @model.restore_attributes
 
-    assert_not @model.changed?
+    assert_not_predicate @model, :changed?
     assert_equal "Dmitry", @model.name
     assert_equal "Red", @model.color
   end
@@ -184,7 +184,7 @@ class AttributesDirtyTest < ActiveModel::TestCase
 
     @model.restore_attributes(["name"])
 
-    assert @model.changed?
+    assert_predicate @model, :changed?
     assert_equal "Dmitry", @model.name
     assert_equal "White", @model.color
   end
diff --git a/activemodel/test/cases/dirty_test.rb b/activemodel/test/cases/dirty_test.rb
index 8c183ec516..f769eb0da1 100644
--- a/activemodel/test/cases/dirty_test.rb
+++ b/activemodel/test/cases/dirty_test.rb
@@ -64,11 +64,11 @@ class DirtyTest < ActiveModel::TestCase
   end
 
   test "setting attribute will result in change" do
-    assert !@model.changed?
-    assert !@model.name_changed?
+    assert_not_predicate @model, :changed?
+    assert_not_predicate @model, :name_changed?
     @model.name = "Ringo"
-    assert @model.changed?
-    assert @model.name_changed?
+    assert_predicate @model, :changed?
+    assert_predicate @model, :name_changed?
   end
 
   test "list of changed attribute keys" do
@@ -109,38 +109,38 @@ class DirtyTest < ActiveModel::TestCase
 
   test "attribute mutation" do
     @model.instance_variable_set("@name", "Yam".dup)
-    assert !@model.name_changed?
+    assert_not_predicate @model, :name_changed?
     @model.name.replace("Hadad")
-    assert !@model.name_changed?
+    assert_not_predicate @model, :name_changed?
     @model.name_will_change!
     @model.name.replace("Baal")
-    assert @model.name_changed?
+    assert_predicate @model, :name_changed?
   end
 
   test "resetting attribute" do
     @model.name = "Bob"
     @model.restore_name!
     assert_nil @model.name
-    assert !@model.name_changed?
+    assert_not_predicate @model, :name_changed?
   end
 
   test "setting color to same value should not result in change being recorded" do
     @model.color = "red"
-    assert @model.color_changed?
+    assert_predicate @model, :color_changed?
     @model.save
-    assert !@model.color_changed?
-    assert !@model.changed?
+    assert_not_predicate @model, :color_changed?
+    assert_not_predicate @model, :changed?
     @model.color = "red"
-    assert !@model.color_changed?
-    assert !@model.changed?
+    assert_not_predicate @model, :color_changed?
+    assert_not_predicate @model, :changed?
   end
 
   test "saving should reset model's changed status" do
     @model.name = "Alf"
-    assert @model.changed?
+    assert_predicate @model, :changed?
     @model.save
-    assert !@model.changed?
-    assert !@model.name_changed?
+    assert_not_predicate @model, :changed?
+    assert_not_predicate @model, :name_changed?
   end
 
   test "saving should preserve previous changes" do
@@ -164,7 +164,7 @@ class DirtyTest < ActiveModel::TestCase
   test "saving should preserve model's previous changed status" do
     @model.name = "Jericho Cane"
     @model.save
-    assert @model.name_previously_changed?
+    assert_predicate @model, :name_previously_changed?
   end
 
   test "previous value is preserved when changed after save" do
@@ -195,7 +195,7 @@ class DirtyTest < ActiveModel::TestCase
 
   test "using attribute_will_change! with a symbol" do
     @model.size = 1
-    assert @model.size_changed?
+    assert_predicate @model, :size_changed?
   end
 
   test "reload should reset all changes" do
@@ -222,7 +222,7 @@ class DirtyTest < ActiveModel::TestCase
 
     @model.restore_attributes
 
-    assert_not @model.changed?
+    assert_not_predicate @model, :changed?
     assert_equal "Dmitry", @model.name
     assert_equal "Red", @model.color
   end
@@ -236,7 +236,7 @@ class DirtyTest < ActiveModel::TestCase
 
     @model.restore_attributes(["name"])
 
-    assert @model.changed?
+    assert_predicate @model, :changed?
     assert_equal "Dmitry", @model.name
     assert_equal "White", @model.color
   end
diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index 16ace62f26..7d155170d3 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -83,7 +83,7 @@ class ErrorsTest < ActiveModel::TestCase
 
     assert_equal 1, person.errors.count
     person.errors.clear
-    assert person.errors.empty?
+    assert_predicate person.errors, :empty?
   end
 
   test "error access is indifferent" do
@@ -128,8 +128,8 @@ class ErrorsTest < ActiveModel::TestCase
   test "detecting whether there are errors with empty?, blank?, include?" do
     person = Person.new
     person.errors[:foo]
-    assert person.errors.empty?
-    assert person.errors.blank?
+    assert_predicate person.errors, :empty?
+    assert_predicate person.errors, :blank?
     assert_not_includes person.errors, :foo
   end
 
@@ -371,7 +371,7 @@ class ErrorsTest < ActiveModel::TestCase
 
     assert_equal 1, person.errors.details.count
     person.errors.clear
-    assert person.errors.details.empty?
+    assert_predicate person.errors.details, :empty?
   end
 
   test "copy errors" do
diff --git a/activemodel/test/cases/type/boolean_test.rb b/activemodel/test/cases/type/boolean_test.rb
index 2d33579595..2de0f53640 100644
--- a/activemodel/test/cases/type/boolean_test.rb
+++ b/activemodel/test/cases/type/boolean_test.rb
@@ -7,8 +7,8 @@ module ActiveModel
     class BooleanTest < ActiveModel::TestCase
       def test_type_cast_boolean
         type = Type::Boolean.new
-        assert type.cast("").nil?
-        assert type.cast(nil).nil?
+        assert_predicate type.cast(""), :nil?
+        assert_predicate type.cast(nil), :nil?
 
         assert type.cast(true)
         assert type.cast(1)
diff --git a/activemodel/test/cases/validations/absence_validation_test.rb b/activemodel/test/cases/validations/absence_validation_test.rb
index 801577474a..8bc4f4723a 100644
--- a/activemodel/test/cases/validations/absence_validation_test.rb
+++ b/activemodel/test/cases/validations/absence_validation_test.rb
@@ -17,16 +17,16 @@ class AbsenceValidationTest < ActiveModel::TestCase
     t = Topic.new
     t.title = "foo"
     t.content = "bar"
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["must be blank"], t.errors[:title]
     assert_equal ["must be blank"], t.errors[:content]
     t.title = ""
     t.content = "something"
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["must be blank"], t.errors[:content]
     assert_equal [], t.errors[:title]
     t.content = ""
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_absence_of_with_array_arguments
@@ -34,7 +34,7 @@ class AbsenceValidationTest < ActiveModel::TestCase
     t = Topic.new
     t.title = "foo"
     t.content = "bar"
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["must be blank"], t.errors[:title]
     assert_equal ["must be blank"], t.errors[:content]
   end
@@ -43,7 +43,7 @@ class AbsenceValidationTest < ActiveModel::TestCase
     Person.validates_absence_of :karma, message: "This string contains 'single' and \"double\" quotes"
     p = Person.new
     p.karma = "good"
-    assert p.invalid?
+    assert_predicate p, :invalid?
     assert_equal "This string contains 'single' and \"double\" quotes", p.errors[:karma].last
   end
 
@@ -51,19 +51,19 @@ class AbsenceValidationTest < ActiveModel::TestCase
     Person.validates_absence_of :karma
     p = Person.new
     p.karma = "good"
-    assert p.invalid?
+    assert_predicate p, :invalid?
     assert_equal ["must be blank"], p.errors[:karma]
     p.karma = nil
-    assert p.valid?
+    assert_predicate p, :valid?
   end
 
   def test_validates_absence_of_for_ruby_class_with_custom_reader
     CustomReader.validates_absence_of :karma
     p = CustomReader.new
     p[:karma] = "excellent"
-    assert p.invalid?
+    assert_predicate p, :invalid?
     assert_equal ["must be blank"], p.errors[:karma]
     p[:karma] = ""
-    assert p.valid?
+    assert_predicate p, :valid?
   end
 end
diff --git a/activemodel/test/cases/validations/acceptance_validation_test.rb b/activemodel/test/cases/validations/acceptance_validation_test.rb
index c5f54b1868..7662f996ae 100644
--- a/activemodel/test/cases/validations/acceptance_validation_test.rb
+++ b/activemodel/test/cases/validations/acceptance_validation_test.rb
@@ -15,54 +15,54 @@ class AcceptanceValidationTest < ActiveModel::TestCase
     Topic.validates_acceptance_of(:terms_of_service)
 
     t = Topic.new("title" => "We should not be confirmed")
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_terms_of_service_agreement
     Topic.validates_acceptance_of(:terms_of_service)
 
     t = Topic.new("title" => "We should be confirmed", "terms_of_service" => "")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["must be accepted"], t.errors[:terms_of_service]
 
     t.terms_of_service = "1"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_eula
     Topic.validates_acceptance_of(:eula, message: "must be abided")
 
     t = Topic.new("title" => "We should be confirmed", "eula" => "")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["must be abided"], t.errors[:eula]
 
     t.eula = "1"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_terms_of_service_agreement_with_accept_value
     Topic.validates_acceptance_of(:terms_of_service, accept: "I agree.")
 
     t = Topic.new("title" => "We should be confirmed", "terms_of_service" => "")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["must be accepted"], t.errors[:terms_of_service]
 
     t.terms_of_service = "I agree."
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_terms_of_service_agreement_with_multiple_accept_values
     Topic.validates_acceptance_of(:terms_of_service, accept: [1, "I concur."])
 
     t = Topic.new("title" => "We should be confirmed", "terms_of_service" => "")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["must be accepted"], t.errors[:terms_of_service]
 
     t.terms_of_service = 1
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.terms_of_service = "I concur."
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_acceptance_of_for_ruby_class
@@ -71,11 +71,11 @@ class AcceptanceValidationTest < ActiveModel::TestCase
     p = Person.new
     p.karma = ""
 
-    assert p.invalid?
+    assert_predicate p, :invalid?
     assert_equal ["must be accepted"], p.errors[:karma]
 
     p.karma = "1"
-    assert p.valid?
+    assert_predicate p, :valid?
   ensure
     Person.clear_validators!
   end
@@ -83,6 +83,6 @@ class AcceptanceValidationTest < ActiveModel::TestCase
   def test_validates_acceptance_of_true
     Topic.validates_acceptance_of(:terms_of_service)
 
-    assert Topic.new(terms_of_service: true).valid?
+    assert_predicate Topic.new(terms_of_service: true), :valid?
   end
 end
diff --git a/activemodel/test/cases/validations/conditional_validation_test.rb b/activemodel/test/cases/validations/conditional_validation_test.rb
index caea8b65ef..1704db9a48 100644
--- a/activemodel/test/cases/validations/conditional_validation_test.rb
+++ b/activemodel/test/cases/validations/conditional_validation_test.rb
@@ -13,24 +13,24 @@ class ConditionalValidationTest < ActiveModel::TestCase
     # When the method returns true
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: :condition_is_true)
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
   def test_if_validation_using_array_of_true_methods
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: [:condition_is_true, :condition_is_true])
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
   def test_unless_validation_using_array_of_false_methods
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: [:condition_is_false, :condition_is_false])
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
@@ -38,21 +38,21 @@ class ConditionalValidationTest < ActiveModel::TestCase
     # When the method returns true
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: :condition_is_true)
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
     assert_empty t.errors[:title]
   end
 
   def test_if_validation_using_array_of_true_and_false_methods
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: [:condition_is_true, :condition_is_false])
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
     assert_empty t.errors[:title]
   end
 
   def test_unless_validation_using_array_of_true_and_felse_methods
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: [:condition_is_true, :condition_is_false])
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
     assert_empty t.errors[:title]
   end
 
@@ -60,7 +60,7 @@ class ConditionalValidationTest < ActiveModel::TestCase
     # When the method returns false
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: :condition_is_false)
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
     assert_empty t.errors[:title]
   end
 
@@ -68,8 +68,8 @@ class ConditionalValidationTest < ActiveModel::TestCase
     # When the method returns false
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", unless: :condition_is_false)
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
@@ -78,8 +78,8 @@ class ConditionalValidationTest < ActiveModel::TestCase
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}",
       if: Proc.new { |r| r.content.size > 4 })
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
@@ -88,7 +88,7 @@ class ConditionalValidationTest < ActiveModel::TestCase
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}",
       unless: Proc.new { |r| r.content.size > 4 })
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
     assert_empty t.errors[:title]
   end
 
@@ -97,7 +97,7 @@ class ConditionalValidationTest < ActiveModel::TestCase
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}",
       if: Proc.new { |r| r.title != "uhohuhoh" })
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
     assert_empty t.errors[:title]
   end
 
@@ -106,23 +106,23 @@ class ConditionalValidationTest < ActiveModel::TestCase
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}",
       unless: Proc.new { |r| r.title != "uhohuhoh" })
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
   def test_validation_using_conbining_if_true_and_unless_true_conditions
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: :condition_is_true, unless: :condition_is_true)
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
     assert_empty t.errors[:title]
   end
 
   def test_validation_using_conbining_if_true_and_unless_false_conditions
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}", if: :condition_is_true, unless: :condition_is_false)
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 end
diff --git a/activemodel/test/cases/validations/confirmation_validation_test.rb b/activemodel/test/cases/validations/confirmation_validation_test.rb
index 8b2c65289b..8603a8ac5c 100644
--- a/activemodel/test/cases/validations/confirmation_validation_test.rb
+++ b/activemodel/test/cases/validations/confirmation_validation_test.rb
@@ -14,40 +14,40 @@ class ConfirmationValidationTest < ActiveModel::TestCase
     Topic.validates_confirmation_of(:title)
 
     t = Topic.new(author_name: "Plutarch")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title_confirmation = "Parallel Lives"
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.title_confirmation = nil
     t.title = "Parallel Lives"
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title_confirmation = "Parallel Lives"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_title_confirmation
     Topic.validates_confirmation_of(:title)
 
     t = Topic.new("title" => "We should be confirmed", "title_confirmation" => "")
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.title_confirmation = "We should be confirmed"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_confirmation_of_with_boolean_attribute
     Topic.validates_confirmation_of(:approved)
 
     t = Topic.new(approved: true, approved_confirmation: nil)
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.approved_confirmation = false
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.approved_confirmation = true
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_confirmation_of_for_ruby_class
@@ -55,12 +55,12 @@ class ConfirmationValidationTest < ActiveModel::TestCase
 
     p = Person.new
     p.karma_confirmation = "None"
-    assert p.invalid?
+    assert_predicate p, :invalid?
 
     assert_equal ["doesn't match Karma"], p.errors[:karma_confirmation]
 
     p.karma = "None"
-    assert p.valid?
+    assert_predicate p, :valid?
   ensure
     Person.clear_validators!
   end
@@ -77,7 +77,7 @@ class ConfirmationValidationTest < ActiveModel::TestCase
       Topic.validates_confirmation_of(:title)
 
       t = Topic.new("title" => "We should be confirmed", "title_confirmation" => "")
-      assert t.invalid?
+      assert_predicate t, :invalid?
       assert_equal ["doesn't match Test Title"], t.errors[:title_confirmation]
     ensure
       I18n.load_path.replace @old_load_path
@@ -122,13 +122,13 @@ class ConfirmationValidationTest < ActiveModel::TestCase
     Topic.validates_confirmation_of(:title, case_sensitive: true)
 
     t = Topic.new(title: "title", title_confirmation: "Title")
-    assert t.invalid?
+    assert_predicate t, :invalid?
   end
 
   def test_title_confirmation_with_case_sensitive_option_false
     Topic.validates_confirmation_of(:title, case_sensitive: false)
 
     t = Topic.new(title: "title", title_confirmation: "Title")
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 end
diff --git a/activemodel/test/cases/validations/exclusion_validation_test.rb b/activemodel/test/cases/validations/exclusion_validation_test.rb
index 68d611e904..50bd47065c 100644
--- a/activemodel/test/cases/validations/exclusion_validation_test.rb
+++ b/activemodel/test/cases/validations/exclusion_validation_test.rb
@@ -14,8 +14,8 @@ class ExclusionValidationTest < ActiveModel::TestCase
   def test_validates_exclusion_of
     Topic.validates_exclusion_of(:title, in: %w( abe monkey ))
 
-    assert Topic.new("title" => "something", "content" => "abc").valid?
-    assert Topic.new("title" => "monkey", "content" => "abc").invalid?
+    assert_predicate Topic.new("title" => "something", "content" => "abc"), :valid?
+    assert_predicate Topic.new("title" => "monkey", "content" => "abc"), :invalid?
   end
 
   def test_validates_exclusion_of_with_formatted_message
@@ -24,8 +24,8 @@ class ExclusionValidationTest < ActiveModel::TestCase
     assert Topic.new("title" => "something", "content" => "abc")
 
     t = Topic.new("title" => "monkey")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["option monkey is restricted"], t.errors[:title]
   end
 
@@ -35,8 +35,8 @@ class ExclusionValidationTest < ActiveModel::TestCase
     assert Topic.new("title" => "something", "content" => "abc")
 
     t = Topic.new("title" => "monkey")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
   end
 
   def test_validates_exclusion_of_for_ruby_class
@@ -44,12 +44,12 @@ class ExclusionValidationTest < ActiveModel::TestCase
 
     p = Person.new
     p.karma = "abe"
-    assert p.invalid?
+    assert_predicate p, :invalid?
 
     assert_equal ["is reserved"], p.errors[:karma]
 
     p.karma = "Lifo"
-    assert p.valid?
+    assert_predicate p, :valid?
   ensure
     Person.clear_validators!
   end
@@ -60,26 +60,26 @@ class ExclusionValidationTest < ActiveModel::TestCase
     t = Topic.new
     t.title = "elephant"
     t.author_name = "sikachu"
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.title = "wasabi"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_exclusion_of_with_range
     Topic.validates_exclusion_of :content, in: ("a".."g")
 
-    assert Topic.new(content: "g").invalid?
-    assert Topic.new(content: "h").valid?
+    assert_predicate Topic.new(content: "g"), :invalid?
+    assert_predicate Topic.new(content: "h"), :valid?
   end
 
   def test_validates_exclusion_of_with_time_range
     Topic.validates_exclusion_of :created_at, in: 6.days.ago..2.days.ago
 
-    assert Topic.new(created_at: 5.days.ago).invalid?
-    assert Topic.new(created_at: 3.days.ago).invalid?
-    assert Topic.new(created_at: 7.days.ago).valid?
-    assert Topic.new(created_at: 1.day.ago).valid?
+    assert_predicate Topic.new(created_at: 5.days.ago), :invalid?
+    assert_predicate Topic.new(created_at: 3.days.ago), :invalid?
+    assert_predicate Topic.new(created_at: 7.days.ago), :valid?
+    assert_predicate Topic.new(created_at: 1.day.ago), :valid?
   end
 
   def test_validates_inclusion_of_with_symbol
@@ -92,7 +92,7 @@ class ExclusionValidationTest < ActiveModel::TestCase
       %w(abe)
     end
 
-    assert p.invalid?
+    assert_predicate p, :invalid?
     assert_equal ["is reserved"], p.errors[:karma]
 
     p = Person.new
@@ -102,7 +102,7 @@ class ExclusionValidationTest < ActiveModel::TestCase
       %w()
     end
 
-    assert p.valid?
+    assert_predicate p, :valid?
   ensure
     Person.clear_validators!
   end
diff --git a/activemodel/test/cases/validations/format_validation_test.rb b/activemodel/test/cases/validations/format_validation_test.rb
index b0de80a6fc..e9430cc7c4 100644
--- a/activemodel/test/cases/validations/format_validation_test.rb
+++ b/activemodel/test/cases/validations/format_validation_test.rb
@@ -16,22 +16,22 @@ class FormatValidationTest < ActiveModel::TestCase
     t = Topic.new("title" => "i'm incorrect", "content" => "Validation macros rule!")
     assert t.invalid?, "Shouldn't be valid"
     assert_equal ["is bad data"], t.errors[:title]
-    assert t.errors[:content].empty?
+    assert_predicate t.errors[:content], :empty?
 
     t.title = "Validation macros rule!"
 
-    assert t.valid?
-    assert t.errors[:title].empty?
+    assert_predicate t, :valid?
+    assert_predicate t.errors[:title], :empty?
 
     assert_raise(ArgumentError) { Topic.validates_format_of(:title, :content) }
   end
 
   def test_validate_format_with_allow_blank
     Topic.validates_format_of(:title, with: /\AValidation\smacros \w+!\z/, allow_blank: true)
-    assert Topic.new("title" => "Shouldn't be valid").invalid?
-    assert Topic.new("title" => "").valid?
-    assert Topic.new("title" => nil).valid?
-    assert Topic.new("title" => "Validation macros rule!").valid?
+    assert_predicate Topic.new("title" => "Shouldn't be valid"), :invalid?
+    assert_predicate Topic.new("title" => ""), :valid?
+    assert_predicate Topic.new("title" => nil), :valid?
+    assert_predicate Topic.new("title" => "Validation macros rule!"), :valid?
   end
 
   # testing ticket #3142
@@ -42,7 +42,7 @@ class FormatValidationTest < ActiveModel::TestCase
     assert t.invalid?, "Shouldn't be valid"
 
     assert_equal ["is bad data"], t.errors[:title]
-    assert t.errors[:content].empty?
+    assert_predicate t.errors[:content], :empty?
 
     t.title = "-11"
     assert t.invalid?, "Shouldn't be valid"
@@ -58,14 +58,14 @@ class FormatValidationTest < ActiveModel::TestCase
 
     t.title = "1"
 
-    assert t.valid?
-    assert t.errors[:title].empty?
+    assert_predicate t, :valid?
+    assert_predicate t.errors[:title], :empty?
   end
 
   def test_validate_format_with_formatted_message
     Topic.validates_format_of(:title, with: /\AValid Title\z/, message: "can't be %{value}")
     t = Topic.new(title: "Invalid title")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["can't be Invalid title"], t.errors[:title]
   end
 
@@ -114,10 +114,10 @@ class FormatValidationTest < ActiveModel::TestCase
     t = Topic.new
     t.title = "digit"
     t.content = "Pixies"
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.content = "1234"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_format_of_without_lambda
@@ -126,10 +126,10 @@ class FormatValidationTest < ActiveModel::TestCase
     t = Topic.new
     t.title = "characters"
     t.content = "1234"
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.content = "Pixies"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_format_of_for_ruby_class
@@ -137,12 +137,12 @@ class FormatValidationTest < ActiveModel::TestCase
 
     p = Person.new
     p.karma = "Pixies"
-    assert p.invalid?
+    assert_predicate p, :invalid?
 
     assert_equal ["is invalid"], p.errors[:karma]
 
     p.karma = "1234"
-    assert p.valid?
+    assert_predicate p, :valid?
   ensure
     Person.clear_validators!
   end
diff --git a/activemodel/test/cases/validations/inclusion_validation_test.rb b/activemodel/test/cases/validations/inclusion_validation_test.rb
index 94df0649a9..daad76759f 100644
--- a/activemodel/test/cases/validations/inclusion_validation_test.rb
+++ b/activemodel/test/cases/validations/inclusion_validation_test.rb
@@ -13,61 +13,61 @@ class InclusionValidationTest < ActiveModel::TestCase
 
   def test_validates_inclusion_of_range
     Topic.validates_inclusion_of(:title, in: "aaa".."bbb")
-    assert Topic.new("title" => "bbc", "content" => "abc").invalid?
-    assert Topic.new("title" => "aa", "content" => "abc").invalid?
-    assert Topic.new("title" => "aaab", "content" => "abc").invalid?
-    assert Topic.new("title" => "aaa", "content" => "abc").valid?
-    assert Topic.new("title" => "abc", "content" => "abc").valid?
-    assert Topic.new("title" => "bbb", "content" => "abc").valid?
+    assert_predicate Topic.new("title" => "bbc", "content" => "abc"), :invalid?
+    assert_predicate Topic.new("title" => "aa", "content" => "abc"), :invalid?
+    assert_predicate Topic.new("title" => "aaab", "content" => "abc"), :invalid?
+    assert_predicate Topic.new("title" => "aaa", "content" => "abc"), :valid?
+    assert_predicate Topic.new("title" => "abc", "content" => "abc"), :valid?
+    assert_predicate Topic.new("title" => "bbb", "content" => "abc"), :valid?
   end
 
   def test_validates_inclusion_of_time_range
     range_begin = 1.year.ago
     range_end = Time.now
     Topic.validates_inclusion_of(:created_at, in: range_begin..range_end)
-    assert Topic.new(title: "aaa", created_at: 2.years.ago).invalid?
-    assert Topic.new(title: "aaa", created_at: 3.months.ago).valid?
-    assert Topic.new(title: "aaa", created_at: 37.weeks.from_now).invalid?
-    assert Topic.new(title: "aaa", created_at: range_begin).valid?
-    assert Topic.new(title: "aaa", created_at: range_end).valid?
+    assert_predicate Topic.new(title: "aaa", created_at: 2.years.ago), :invalid?
+    assert_predicate Topic.new(title: "aaa", created_at: 3.months.ago), :valid?
+    assert_predicate Topic.new(title: "aaa", created_at: 37.weeks.from_now), :invalid?
+    assert_predicate Topic.new(title: "aaa", created_at: range_begin), :valid?
+    assert_predicate Topic.new(title: "aaa", created_at: range_end), :valid?
   end
 
   def test_validates_inclusion_of_date_range
     range_begin = 1.year.until(Date.today)
     range_end = Date.today
     Topic.validates_inclusion_of(:created_at, in: range_begin..range_end)
-    assert Topic.new(title: "aaa", created_at: 2.years.until(Date.today)).invalid?
-    assert Topic.new(title: "aaa", created_at: 3.months.until(Date.today)).valid?
-    assert Topic.new(title: "aaa", created_at: 37.weeks.since(Date.today)).invalid?
-    assert Topic.new(title: "aaa", created_at: 1.year.until(Date.today)).valid?
-    assert Topic.new(title: "aaa", created_at: Date.today).valid?
-    assert Topic.new(title: "aaa", created_at: range_begin).valid?
-    assert Topic.new(title: "aaa", created_at: range_end).valid?
+    assert_predicate Topic.new(title: "aaa", created_at: 2.years.until(Date.today)), :invalid?
+    assert_predicate Topic.new(title: "aaa", created_at: 3.months.until(Date.today)), :valid?
+    assert_predicate Topic.new(title: "aaa", created_at: 37.weeks.since(Date.today)), :invalid?
+    assert_predicate Topic.new(title: "aaa", created_at: 1.year.until(Date.today)), :valid?
+    assert_predicate Topic.new(title: "aaa", created_at: Date.today), :valid?
+    assert_predicate Topic.new(title: "aaa", created_at: range_begin), :valid?
+    assert_predicate Topic.new(title: "aaa", created_at: range_end), :valid?
   end
 
   def test_validates_inclusion_of_date_time_range
     range_begin = 1.year.until(DateTime.current)
     range_end = DateTime.current
     Topic.validates_inclusion_of(:created_at, in: range_begin..range_end)
-    assert Topic.new(title: "aaa", created_at: 2.years.until(DateTime.current)).invalid?
-    assert Topic.new(title: "aaa", created_at: 3.months.until(DateTime.current)).valid?
-    assert Topic.new(title: "aaa", created_at: 37.weeks.since(DateTime.current)).invalid?
-    assert Topic.new(title: "aaa", created_at: range_begin).valid?
-    assert Topic.new(title: "aaa", created_at: range_end).valid?
+    assert_predicate Topic.new(title: "aaa", created_at: 2.years.until(DateTime.current)), :invalid?
+    assert_predicate Topic.new(title: "aaa", created_at: 3.months.until(DateTime.current)), :valid?
+    assert_predicate Topic.new(title: "aaa", created_at: 37.weeks.since(DateTime.current)), :invalid?
+    assert_predicate Topic.new(title: "aaa", created_at: range_begin), :valid?
+    assert_predicate Topic.new(title: "aaa", created_at: range_end), :valid?
   end
 
   def test_validates_inclusion_of
     Topic.validates_inclusion_of(:title, in: %w( a b c d e f g ))
 
-    assert Topic.new("title" => "a!", "content" => "abc").invalid?
-    assert Topic.new("title" => "a b", "content" => "abc").invalid?
-    assert Topic.new("title" => nil, "content" => "def").invalid?
+    assert_predicate Topic.new("title" => "a!", "content" => "abc"), :invalid?
+    assert_predicate Topic.new("title" => "a b", "content" => "abc"), :invalid?
+    assert_predicate Topic.new("title" => nil, "content" => "def"), :invalid?
 
     t = Topic.new("title" => "a", "content" => "I know you are but what am I?")
-    assert t.valid?
+    assert_predicate t, :valid?
     t.title = "uhoh"
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is not included in the list"], t.errors[:title]
 
     assert_raise(ArgumentError) { Topic.validates_inclusion_of(:title, in: nil) }
@@ -81,30 +81,30 @@ class InclusionValidationTest < ActiveModel::TestCase
   def test_validates_inclusion_of_with_allow_nil
     Topic.validates_inclusion_of(:title, in: %w( a b c d e f g ), allow_nil: true)
 
-    assert Topic.new("title" => "a!", "content" => "abc").invalid?
-    assert Topic.new("title" => "",   "content" => "abc").invalid?
-    assert Topic.new("title" => nil,  "content" => "abc").valid?
+    assert_predicate Topic.new("title" => "a!", "content" => "abc"), :invalid?
+    assert_predicate Topic.new("title" => "",   "content" => "abc"), :invalid?
+    assert_predicate Topic.new("title" => nil,  "content" => "abc"), :valid?
   end
 
   def test_validates_inclusion_of_with_formatted_message
     Topic.validates_inclusion_of(:title, in: %w( a b c d e f g ), message: "option %{value} is not in the list")
 
-    assert Topic.new("title" => "a", "content" => "abc").valid?
+    assert_predicate Topic.new("title" => "a", "content" => "abc"), :valid?
 
     t = Topic.new("title" => "uhoh", "content" => "abc")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["option uhoh is not in the list"], t.errors[:title]
   end
 
   def test_validates_inclusion_of_with_within_option
     Topic.validates_inclusion_of(:title, within: %w( a b c d e f g ))
 
-    assert Topic.new("title" => "a", "content" => "abc").valid?
+    assert_predicate Topic.new("title" => "a", "content" => "abc"), :valid?
 
     t = Topic.new("title" => "uhoh", "content" => "abc")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
   end
 
   def test_validates_inclusion_of_for_ruby_class
@@ -112,12 +112,12 @@ class InclusionValidationTest < ActiveModel::TestCase
 
     p = Person.new
     p.karma = "Lifo"
-    assert p.invalid?
+    assert_predicate p, :invalid?
 
     assert_equal ["is not included in the list"], p.errors[:karma]
 
     p.karma = "monkey"
-    assert p.valid?
+    assert_predicate p, :valid?
   ensure
     Person.clear_validators!
   end
@@ -128,10 +128,10 @@ class InclusionValidationTest < ActiveModel::TestCase
     t = Topic.new
     t.title = "wasabi"
     t.author_name = "sikachu"
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.title = "elephant"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_inclusion_of_with_symbol
@@ -144,7 +144,7 @@ class InclusionValidationTest < ActiveModel::TestCase
       %w()
     end
 
-    assert p.invalid?
+    assert_predicate p, :invalid?
     assert_equal ["is not included in the list"], p.errors[:karma]
 
     p = Person.new
@@ -154,7 +154,7 @@ class InclusionValidationTest < ActiveModel::TestCase
       %w(Lifo)
     end
 
-    assert p.valid?
+    assert_predicate p, :valid?
   ensure
     Person.clear_validators!
   end
diff --git a/activemodel/test/cases/validations/length_validation_test.rb b/activemodel/test/cases/validations/length_validation_test.rb
index 42f76f3e3c..774a2cde74 100644
--- a/activemodel/test/cases/validations/length_validation_test.rb
+++ b/activemodel/test/cases/validations/length_validation_test.rb
@@ -13,153 +13,153 @@ class LengthValidationTest < ActiveModel::TestCase
   def test_validates_length_of_with_allow_nil
     Topic.validates_length_of(:title, is: 5, allow_nil: true)
 
-    assert Topic.new("title" => "ab").invalid?
-    assert Topic.new("title" => "").invalid?
-    assert Topic.new("title" => nil).valid?
-    assert Topic.new("title" => "abcde").valid?
+    assert_predicate Topic.new("title" => "ab"), :invalid?
+    assert_predicate Topic.new("title" => ""), :invalid?
+    assert_predicate Topic.new("title" => nil), :valid?
+    assert_predicate Topic.new("title" => "abcde"), :valid?
   end
 
   def test_validates_length_of_with_allow_blank
     Topic.validates_length_of(:title, is: 5, allow_blank: true)
 
-    assert Topic.new("title" => "ab").invalid?
-    assert Topic.new("title" => "").valid?
-    assert Topic.new("title" => nil).valid?
-    assert Topic.new("title" => "abcde").valid?
+    assert_predicate Topic.new("title" => "ab"), :invalid?
+    assert_predicate Topic.new("title" => ""), :valid?
+    assert_predicate Topic.new("title" => nil), :valid?
+    assert_predicate Topic.new("title" => "abcde"), :valid?
   end
 
   def test_validates_length_of_using_minimum
     Topic.validates_length_of :title, minimum: 5
 
     t = Topic.new("title" => "valid", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = "not"
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is too short (minimum is 5 characters)"], t.errors[:title]
 
     t.title = ""
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is too short (minimum is 5 characters)"], t.errors[:title]
 
     t.title = nil
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is too short (minimum is 5 characters)"], t.errors["title"]
   end
 
   def test_validates_length_of_using_maximum_should_allow_nil
     Topic.validates_length_of :title, maximum: 10
     t = Topic.new
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_optionally_validates_length_of_using_minimum
     Topic.validates_length_of :title, minimum: 5, allow_nil: true
 
     t = Topic.new("title" => "valid", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = nil
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_length_of_using_maximum
     Topic.validates_length_of :title, maximum: 5
 
     t = Topic.new("title" => "valid", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = "notvalid"
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is too long (maximum is 5 characters)"], t.errors[:title]
 
     t.title = ""
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_optionally_validates_length_of_using_maximum
     Topic.validates_length_of :title, maximum: 5, allow_nil: true
 
     t = Topic.new("title" => "valid", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = nil
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_length_of_using_within
     Topic.validates_length_of(:title, :content, within: 3..5)
 
     t = Topic.new("title" => "a!", "content" => "I'm ooooooooh so very long")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["is too short (minimum is 3 characters)"], t.errors[:title]
     assert_equal ["is too long (maximum is 5 characters)"], t.errors[:content]
 
     t.title = nil
     t.content = nil
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["is too short (minimum is 3 characters)"], t.errors[:title]
     assert_equal ["is too short (minimum is 3 characters)"], t.errors[:content]
 
     t.title = "abe"
     t.content = "mad"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_length_of_using_within_with_exclusive_range
     Topic.validates_length_of(:title, within: 4...10)
 
     t = Topic.new("title" => "9 chars!!")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = "Now I'm 10"
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["is too long (maximum is 9 characters)"], t.errors[:title]
 
     t.title = "Four"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_optionally_validates_length_of_using_within
     Topic.validates_length_of :title, :content, within: 3..5, allow_nil: true
 
     t = Topic.new("title" => "abc", "content" => "abcd")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = nil
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_length_of_using_is
     Topic.validates_length_of :title, is: 5
 
     t = Topic.new("title" => "valid", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = "notvalid"
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is the wrong length (should be 5 characters)"], t.errors[:title]
 
     t.title = ""
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.title = nil
-    assert t.invalid?
+    assert_predicate t, :invalid?
   end
 
   def test_optionally_validates_length_of_using_is
     Topic.validates_length_of :title, is: 5, allow_nil: true
 
     t = Topic.new("title" => "valid", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = nil
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_length_of_using_bignum
@@ -187,45 +187,45 @@ class LengthValidationTest < ActiveModel::TestCase
   def test_validates_length_of_custom_errors_for_minimum_with_message
     Topic.validates_length_of(:title, minimum: 5, message: "boo %{count}")
     t = Topic.new("title" => "uhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["boo 5"], t.errors[:title]
   end
 
   def test_validates_length_of_custom_errors_for_minimum_with_too_short
     Topic.validates_length_of(:title, minimum: 5, too_short: "hoo %{count}")
     t = Topic.new("title" => "uhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors[:title]
   end
 
   def test_validates_length_of_custom_errors_for_maximum_with_message
     Topic.validates_length_of(:title, maximum: 5, message: "boo %{count}")
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["boo 5"], t.errors[:title]
   end
 
   def test_validates_length_of_custom_errors_for_in
     Topic.validates_length_of(:title, in: 10..20, message: "hoo %{count}")
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 10"], t.errors["title"]
 
     t = Topic.new("title" => "uhohuhohuhohuhohuhohuhohuhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 20"], t.errors["title"]
   end
 
   def test_validates_length_of_custom_errors_for_maximum_with_too_long
     Topic.validates_length_of(:title, maximum: 5, too_long: "hoo %{count}")
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
@@ -233,29 +233,29 @@ class LengthValidationTest < ActiveModel::TestCase
     Topic.validates_length_of :title, minimum: 3, maximum: 5, too_short: "too short", too_long: "too long"
 
     t = Topic.new(title: "a")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["too short"], t.errors["title"]
 
     t = Topic.new(title: "aaaaaa")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["too long"], t.errors["title"]
   end
 
   def test_validates_length_of_custom_errors_for_is_with_message
     Topic.validates_length_of(:title, is: 5, message: "boo %{count}")
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["boo 5"], t.errors["title"]
   end
 
   def test_validates_length_of_custom_errors_for_is_with_wrong_length
     Topic.validates_length_of(:title, is: 5, wrong_length: "hoo %{count}")
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["hoo 5"], t.errors["title"]
   end
 
@@ -263,11 +263,11 @@ class LengthValidationTest < ActiveModel::TestCase
     Topic.validates_length_of :title, minimum: 5
 
     t = Topic.new("title" => "一二三四五", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = "一二三四"
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is too short (minimum is 5 characters)"], t.errors["title"]
   end
 
@@ -275,11 +275,11 @@ class LengthValidationTest < ActiveModel::TestCase
     Topic.validates_length_of :title, maximum: 5
 
     t = Topic.new("title" => "一二三四五", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = "一二34五六"
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is too long (maximum is 5 characters)"], t.errors["title"]
   end
 
@@ -287,12 +287,12 @@ class LengthValidationTest < ActiveModel::TestCase
     Topic.validates_length_of(:title, :content, within: 3..5)
 
     t = Topic.new("title" => "一二", "content" => "12三四五六七")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["is too short (minimum is 3 characters)"], t.errors[:title]
     assert_equal ["is too long (maximum is 5 characters)"], t.errors[:content]
     t.title = "一二三"
     t.content = "12三"
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_optionally_validates_length_of_using_within_utf8
@@ -312,11 +312,11 @@ class LengthValidationTest < ActiveModel::TestCase
     Topic.validates_length_of :title, is: 5
 
     t = Topic.new("title" => "一二345", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = "一二345六"
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is the wrong length (should be 5 characters)"], t.errors["title"]
   end
 
@@ -324,11 +324,11 @@ class LengthValidationTest < ActiveModel::TestCase
     Topic.validates_length_of(:approved, is: 4)
 
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever", approved: 1)
-    assert t.invalid?
-    assert t.errors[:approved].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:approved], :any?
 
     t = Topic.new("title" => "uhohuhoh", "content" => "whatever", approved: 1234)
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_length_of_for_ruby_class
@@ -336,12 +336,12 @@ class LengthValidationTest < ActiveModel::TestCase
 
     p = Person.new
     p.karma = "Pix"
-    assert p.invalid?
+    assert_predicate p, :invalid?
 
     assert_equal ["is too short (minimum is 5 characters)"], p.errors[:karma]
 
     p.karma = "The Smiths"
-    assert p.valid?
+    assert_predicate p, :valid?
   ensure
     Person.clear_validators!
   end
@@ -350,80 +350,80 @@ class LengthValidationTest < ActiveModel::TestCase
     Topic.validates_length_of(:title, within: 5..Float::INFINITY)
 
     t = Topic.new("title" => "1234")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
 
     t.title = "12345"
-    assert t.valid?
+    assert_predicate t, :valid?
 
     Topic.validates_length_of(:author_name, maximum: Float::INFINITY)
 
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.author_name = "A very long author name that should still be valid." * 100
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_length_of_using_maximum_should_not_allow_nil_when_nil_not_allowed
     Topic.validates_length_of :title, maximum: 10, allow_nil: false
     t = Topic.new
-    assert t.invalid?
+    assert_predicate t, :invalid?
   end
 
   def test_validates_length_of_using_maximum_should_not_allow_nil_and_empty_string_when_blank_not_allowed
     Topic.validates_length_of :title, maximum: 10, allow_blank: false
     t = Topic.new
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.title = ""
-    assert t.invalid?
+    assert_predicate t, :invalid?
   end
 
   def test_validates_length_of_using_both_minimum_and_maximum_should_not_allow_nil
     Topic.validates_length_of :title, minimum: 5, maximum: 10
     t = Topic.new
-    assert t.invalid?
+    assert_predicate t, :invalid?
   end
 
   def test_validates_length_of_using_minimum_0_should_not_allow_nil
     Topic.validates_length_of :title, minimum: 0
     t = Topic.new
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.title = ""
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_length_of_using_is_0_should_not_allow_nil
     Topic.validates_length_of :title, is: 0
     t = Topic.new
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     t.title = ""
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_with_diff_in_option
     Topic.validates_length_of(:title, is: 5)
     Topic.validates_length_of(:title, is: 5, if: Proc.new { false })
 
-    assert Topic.new("title" => "david").valid?
-    assert Topic.new("title" => "david2").invalid?
+    assert_predicate Topic.new("title" => "david"), :valid?
+    assert_predicate Topic.new("title" => "david2"), :invalid?
   end
 
   def test_validates_length_of_using_proc_as_maximum
     Topic.validates_length_of :title, maximum: ->(model) { 5 }
 
     t = Topic.new("title" => "valid", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = "notvalid"
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is too long (maximum is 5 characters)"], t.errors[:title]
 
     t.title = ""
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_validates_length_of_using_proc_as_maximum_with_model_method
@@ -431,14 +431,14 @@ class LengthValidationTest < ActiveModel::TestCase
     Topic.validates_length_of :title, maximum: Proc.new(&:max_title_length)
 
     t = Topic.new("title" => "valid", "content" => "whatever")
-    assert t.valid?
+    assert_predicate t, :valid?
 
     t.title = "notvalid"
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["is too long (maximum is 5 characters)"], t.errors[:title]
 
     t.title = ""
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 end
diff --git a/activemodel/test/cases/validations/numericality_validation_test.rb b/activemodel/test/cases/validations/numericality_validation_test.rb
index 5413255e6b..01b78ae72e 100644
--- a/activemodel/test/cases/validations/numericality_validation_test.rb
+++ b/activemodel/test/cases/validations/numericality_validation_test.rb
@@ -237,13 +237,13 @@ class NumericalityValidationTest < ActiveModel::TestCase
     Topic.validates_numericality_of :approved, less_than: 4, message: "smaller than %{count}"
     topic = Topic.new("title" => "numeric test", "approved" => 10)
 
-    assert !topic.valid?
+    assert_not_predicate topic, :valid?
     assert_equal ["smaller than 4"], topic.errors[:approved]
 
     Topic.validates_numericality_of :approved, greater_than: 4, message: "greater than %{count}"
     topic = Topic.new("title" => "numeric test", "approved" => 1)
 
-    assert !topic.valid?
+    assert_not_predicate topic, :valid?
     assert_equal ["greater than 4"], topic.errors[:approved]
   end
 
@@ -252,12 +252,12 @@ class NumericalityValidationTest < ActiveModel::TestCase
 
     p = Person.new
     p.karma = "Pix"
-    assert p.invalid?
+    assert_predicate p, :invalid?
 
     assert_equal ["is not a number"], p.errors[:karma]
 
     p.karma = "1234"
-    assert p.valid?
+    assert_predicate p, :valid?
   ensure
     Person.clear_validators!
   end
@@ -268,7 +268,7 @@ class NumericalityValidationTest < ActiveModel::TestCase
     topic = Topic.new
     topic.approved = (base + 1).to_s
 
-    assert topic.invalid?
+    assert_predicate topic, :invalid?
   end
 
   def test_validates_numericality_with_invalid_args
diff --git a/activemodel/test/cases/validations/presence_validation_test.rb b/activemodel/test/cases/validations/presence_validation_test.rb
index 22c2f0af87..c3eca41070 100644
--- a/activemodel/test/cases/validations/presence_validation_test.rb
+++ b/activemodel/test/cases/validations/presence_validation_test.rb
@@ -17,25 +17,25 @@ class PresenceValidationTest < ActiveModel::TestCase
     Topic.validates_presence_of(:title, :content)
 
     t = Topic.new
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["can't be blank"], t.errors[:title]
     assert_equal ["can't be blank"], t.errors[:content]
 
     t.title = "something"
     t.content = "   "
 
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["can't be blank"], t.errors[:content]
 
     t.content = "like stuff"
 
-    assert t.valid?
+    assert_predicate t, :valid?
   end
 
   def test_accepts_array_arguments
     Topic.validates_presence_of %w(title content)
     t = Topic.new
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["can't be blank"], t.errors[:title]
     assert_equal ["can't be blank"], t.errors[:content]
   end
@@ -43,7 +43,7 @@ class PresenceValidationTest < ActiveModel::TestCase
   def test_validates_acceptance_of_with_custom_error_using_quotes
     Person.validates_presence_of :karma, message: "This string contains 'single' and \"double\" quotes"
     p = Person.new
-    assert p.invalid?
+    assert_predicate p, :invalid?
     assert_equal "This string contains 'single' and \"double\" quotes", p.errors[:karma].last
   end
 
@@ -51,24 +51,24 @@ class PresenceValidationTest < ActiveModel::TestCase
     Person.validates_presence_of :karma
 
     p = Person.new
-    assert p.invalid?
+    assert_predicate p, :invalid?
 
     assert_equal ["can't be blank"], p.errors[:karma]
 
     p.karma = "Cold"
-    assert p.valid?
+    assert_predicate p, :valid?
   end
 
   def test_validates_presence_of_for_ruby_class_with_custom_reader
     CustomReader.validates_presence_of :karma
 
     p = CustomReader.new
-    assert p.invalid?
+    assert_predicate p, :invalid?
 
     assert_equal ["can't be blank"], p.errors[:karma]
 
     p[:karma] = "Cold"
-    assert p.valid?
+    assert_predicate p, :valid?
   end
 
   def test_validates_presence_of_with_allow_nil_option
@@ -78,7 +78,7 @@ class PresenceValidationTest < ActiveModel::TestCase
     assert t.valid?, t.errors.full_messages
 
     t.title = ""
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["can't be blank"], t.errors[:title]
 
     t.title = "  "
diff --git a/activemodel/test/cases/validations/validates_test.rb b/activemodel/test/cases/validations/validates_test.rb
index 7f32f5dc74..80c347703a 100644
--- a/activemodel/test/cases/validations/validates_test.rb
+++ b/activemodel/test/cases/validations/validates_test.rb
@@ -37,7 +37,7 @@ class ValidatesTest < ActiveModel::TestCase
 
     person = Person.new
     person.title = 123
-    assert person.valid?
+    assert_predicate person, :valid?
   end
 
   def test_validates_with_built_in_validation_and_options
@@ -71,7 +71,7 @@ class ValidatesTest < ActiveModel::TestCase
   def test_validates_with_if_as_shared_conditions
     Person.validates :karma, presence: true, email: true, if: :condition_is_false
     person = Person.new
-    assert person.valid?
+    assert_predicate person, :valid?
   end
 
   def test_validates_with_unless_as_local_conditions
@@ -84,40 +84,40 @@ class ValidatesTest < ActiveModel::TestCase
   def test_validates_with_unless_shared_conditions
     Person.validates :karma, presence: true, email: true, unless: :condition_is_true
     person = Person.new
-    assert person.valid?
+    assert_predicate person, :valid?
   end
 
   def test_validates_with_allow_nil_shared_conditions
     Person.validates :karma, length: { minimum: 20 }, email: true, allow_nil: true
     person = Person.new
-    assert person.valid?
+    assert_predicate person, :valid?
   end
 
   def test_validates_with_regexp
     Person.validates :karma, format: /positive|negative/
     person = Person.new
-    assert person.invalid?
+    assert_predicate person, :invalid?
     assert_equal ["is invalid"], person.errors[:karma]
     person.karma = "positive"
-    assert person.valid?
+    assert_predicate person, :valid?
   end
 
   def test_validates_with_array
     Person.validates :gender, inclusion: %w(m f)
     person = Person.new
-    assert person.invalid?
+    assert_predicate person, :invalid?
     assert_equal ["is not included in the list"], person.errors[:gender]
     person.gender = "m"
-    assert person.valid?
+    assert_predicate person, :valid?
   end
 
   def test_validates_with_range
     Person.validates :karma, length: 6..20
     person = Person.new
-    assert person.invalid?
+    assert_predicate person, :invalid?
     assert_equal ["is too short (minimum is 6 characters)"], person.errors[:karma]
     person.karma = "something"
-    assert person.valid?
+    assert_predicate person, :valid?
   end
 
   def test_validates_with_validator_class_and_options
@@ -159,7 +159,7 @@ class ValidatesTest < ActiveModel::TestCase
     topic = Topic.new
     topic.title = "What's happening"
     topic.title_confirmation = "Not this"
-    assert !topic.valid?
+    assert_not_predicate topic, :valid?
     assert_equal ["Y U NO CONFIRM"], topic.errors[:title_confirmation]
   end
 end
diff --git a/activemodel/test/cases/validations/with_validation_test.rb b/activemodel/test/cases/validations/with_validation_test.rb
index 13ef5e6a31..b0ebb267f0 100644
--- a/activemodel/test/cases/validations/with_validation_test.rb
+++ b/activemodel/test/cases/validations/with_validation_test.rb
@@ -65,7 +65,7 @@ class ValidatesWithTest < ActiveModel::TestCase
   test "with multiple classes" do
     Topic.validates_with(ValidatorThatAddsErrors, OtherValidatorThatAddsErrors)
     topic = Topic.new
-    assert topic.invalid?
+    assert_predicate topic, :invalid?
     assert_includes topic.errors[:base], ERROR_MESSAGE
     assert_includes topic.errors[:base], OTHER_ERROR_MESSAGE
   end
@@ -79,21 +79,21 @@ class ValidatesWithTest < ActiveModel::TestCase
     validator.expect(:is_a?, false, [String])
 
     Topic.validates_with(validator, if: :condition_is_true, foo: :bar)
-    assert topic.valid?
+    assert_predicate topic, :valid?
     validator.verify
   end
 
   test "validates_with with options" do
     Topic.validates_with(ValidatorThatValidatesOptions, field: :first_name)
     topic = Topic.new
-    assert topic.invalid?
+    assert_predicate topic, :invalid?
     assert_includes topic.errors[:base], ERROR_MESSAGE
   end
 
   test "validates_with each validator" do
     Topic.validates_with(ValidatorPerEachAttribute, attributes: [:title, :content])
     topic = Topic.new title: "Title", content: "Content"
-    assert topic.invalid?
+    assert_predicate topic, :invalid?
     assert_equal ["Value is Title"], topic.errors[:title]
     assert_equal ["Value is Content"], topic.errors[:content]
   end
@@ -113,28 +113,28 @@ class ValidatesWithTest < ActiveModel::TestCase
   test "each validator skip nil values if :allow_nil is set to true" do
     Topic.validates_with(ValidatorPerEachAttribute, attributes: [:title, :content], allow_nil: true)
     topic = Topic.new content: ""
-    assert topic.invalid?
-    assert topic.errors[:title].empty?
+    assert_predicate topic, :invalid?
+    assert_predicate topic.errors[:title], :empty?
     assert_equal ["Value is "], topic.errors[:content]
   end
 
   test "each validator skip blank values if :allow_blank is set to true" do
     Topic.validates_with(ValidatorPerEachAttribute, attributes: [:title, :content], allow_blank: true)
     topic = Topic.new content: ""
-    assert topic.valid?
-    assert topic.errors[:title].empty?
-    assert topic.errors[:content].empty?
+    assert_predicate topic, :valid?
+    assert_predicate topic.errors[:title], :empty?
+    assert_predicate topic.errors[:content], :empty?
   end
 
   test "validates_with can validate with an instance method" do
     Topic.validates :title, with: :my_validation
 
     topic = Topic.new title: "foo"
-    assert topic.valid?
-    assert topic.errors[:title].empty?
+    assert_predicate topic, :valid?
+    assert_predicate topic.errors[:title], :empty?
 
     topic = Topic.new
-    assert !topic.valid?
+    assert_not_predicate topic, :valid?
     assert_equal ["is missing"], topic.errors[:title]
   end
 
@@ -142,8 +142,8 @@ class ValidatesWithTest < ActiveModel::TestCase
     Topic.validates :title, :content, with: :my_validation_with_arg
 
     topic = Topic.new title: "foo"
-    assert !topic.valid?
-    assert topic.errors[:title].empty?
+    assert_not_predicate topic, :valid?
+    assert_predicate topic.errors[:title], :empty?
     assert_equal ["is missing"], topic.errors[:content]
   end
 end
diff --git a/activemodel/test/cases/validations_test.rb b/activemodel/test/cases/validations_test.rb
index ab8c41bbd0..1cf1122618 100644
--- a/activemodel/test/cases/validations_test.rb
+++ b/activemodel/test/cases/validations_test.rb
@@ -30,7 +30,7 @@ class ValidationsTest < ActiveModel::TestCase
   def test_single_attr_validation_and_error_msg
     r = Reply.new
     r.title = "There's no content!"
-    assert r.invalid?
+    assert_predicate r, :invalid?
     assert r.errors[:content].any?, "A reply without content should mark that attribute as invalid"
     assert_equal ["is Empty"], r.errors["content"], "A reply without content should contain an error"
     assert_equal 1, r.errors.count
@@ -38,7 +38,7 @@ class ValidationsTest < ActiveModel::TestCase
 
   def test_double_attr_validation_and_error_msg
     r = Reply.new
-    assert r.invalid?
+    assert_predicate r, :invalid?
 
     assert r.errors[:title].any?, "A reply without title should mark that attribute as invalid"
     assert_equal ["is Empty"], r.errors["title"], "A reply without title should contain an error"
@@ -111,8 +111,8 @@ class ValidationsTest < ActiveModel::TestCase
 
   def test_errors_empty_after_errors_on_check
     t = Topic.new
-    assert t.errors[:id].empty?
-    assert t.errors.empty?
+    assert_predicate t.errors[:id], :empty?
+    assert_predicate t.errors, :empty?
   end
 
   def test_validates_each
@@ -122,7 +122,7 @@ class ValidationsTest < ActiveModel::TestCase
       hits += 1
     end
     t = Topic.new("title" => "valid", "content" => "whatever")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal 4, hits
     assert_equal %w(gotcha gotcha), t.errors[:title]
     assert_equal %w(gotcha gotcha), t.errors[:content]
@@ -135,7 +135,7 @@ class ValidationsTest < ActiveModel::TestCase
       hits += 1
     end
     t = CustomReader.new("title" => "valid", "content" => "whatever")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal 4, hits
     assert_equal %w(gotcha gotcha), t.errors[:title]
     assert_equal %w(gotcha gotcha), t.errors[:content]
@@ -146,16 +146,16 @@ class ValidationsTest < ActiveModel::TestCase
   def test_validate_block
     Topic.validate { errors.add("title", "will never be valid") }
     t = Topic.new("title" => "Title", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["will never be valid"], t.errors["title"]
   end
 
   def test_validate_block_with_params
     Topic.validate { |topic| topic.errors.add("title", "will never be valid") }
     t = Topic.new("title" => "Title", "content" => "whatever")
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
     assert_equal ["will never be valid"], t.errors["title"]
   end
 
@@ -214,7 +214,7 @@ class ValidationsTest < ActiveModel::TestCase
   def test_errors_conversions
     Topic.validates_presence_of %w(title content)
     t = Topic.new
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     xml = t.errors.to_xml
     assert_match %r{<errors>}, xml
@@ -232,14 +232,14 @@ class ValidationsTest < ActiveModel::TestCase
     Topic.validates_length_of :title, minimum: 2
 
     t = Topic.new("title" => "")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal "can't be blank", t.errors["title"].first
     Topic.validates_presence_of :title, :author_name
     Topic.validate { errors.add("author_email_address", "will never be valid") }
     Topic.validates_length_of :title, :content, minimum: 2
 
     t = Topic.new title: ""
-    assert t.invalid?
+    assert_predicate t, :invalid?
 
     assert_equal :title, key = t.errors.keys[0]
     assert_equal "can't be blank", t.errors[key][0]
@@ -258,8 +258,8 @@ class ValidationsTest < ActiveModel::TestCase
     t = Topic.new(title: "")
 
     # If block should not fire
-    assert t.valid?
-    assert t.author_name.nil?
+    assert_predicate t, :valid?
+    assert_predicate t.author_name, :nil?
 
     # If block should fire
     assert t.invalid?(:update)
@@ -270,18 +270,18 @@ class ValidationsTest < ActiveModel::TestCase
     Topic.validates_presence_of :title
 
     t = Topic.new
-    assert t.invalid?
-    assert t.errors[:title].any?
+    assert_predicate t, :invalid?
+    assert_predicate t.errors[:title], :any?
 
     t.title = "Things are going to change"
-    assert !t.invalid?
+    assert_not_predicate t, :invalid?
   end
 
   def test_validation_with_message_as_proc
     Topic.validates_presence_of(:title, message: proc { "no blanks here".upcase })
 
     t = Topic.new
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["NO BLANKS HERE"], t.errors[:title]
   end
 
@@ -331,13 +331,13 @@ class ValidationsTest < ActiveModel::TestCase
     Topic.validates :content, length: { minimum: 10 }
 
     topic = Topic.new
-    assert topic.invalid?
+    assert_predicate topic, :invalid?
     assert_equal 3, topic.errors.size
 
     topic.title = "Some Title"
     topic.author_name = "Some Author"
     topic.content = "Some Content Whose Length is more than 10."
-    assert topic.valid?
+    assert_predicate topic, :valid?
   end
 
   def test_validate
@@ -381,7 +381,7 @@ class ValidationsTest < ActiveModel::TestCase
 
   def test_strict_validation_not_fails
     Topic.validates :title, strict: true, presence: true
-    assert Topic.new(title: "hello").valid?
+    assert_predicate Topic.new(title: "hello"), :valid?
   end
 
   def test_strict_validation_particular_validator
@@ -414,7 +414,7 @@ class ValidationsTest < ActiveModel::TestCase
 
   def test_validates_with_false_hash_value
     Topic.validates :title, presence: false
-    assert Topic.new.valid?
+    assert_predicate Topic.new, :valid?
   end
 
   def test_strict_validation_error_message
@@ -439,19 +439,19 @@ class ValidationsTest < ActiveModel::TestCase
 
     duped = topic.dup
     duped.title = nil
-    assert duped.invalid?
+    assert_predicate duped, :invalid?
 
     topic.title = nil
     duped.title = "Mathematics"
-    assert topic.invalid?
-    assert duped.valid?
+    assert_predicate topic, :invalid?
+    assert_predicate duped, :valid?
   end
 
   def test_validation_with_message_as_proc_that_takes_a_record_as_a_parameter
     Topic.validates_presence_of(:title, message: proc { |record| "You have failed me for the last time, #{record.author_name}." })
 
     t = Topic.new(author_name: "Admiral")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["You have failed me for the last time, Admiral."], t.errors[:title]
   end
 
@@ -459,7 +459,7 @@ class ValidationsTest < ActiveModel::TestCase
     Topic.validates_presence_of(:title, message: proc { |record, data| "#{data[:attribute]} is missing. You have failed me for the last time, #{record.author_name}." })
 
     t = Topic.new(author_name: "Admiral")
-    assert t.invalid?
+    assert_predicate t, :invalid?
     assert_equal ["Title is missing. You have failed me for the last time, Admiral."], t.errors[:title]
   end
 end