Add `ActiveModel::Errors#of_kind?`

Related to https://github.com/rails/rails/pull/34817#issuecomment-451508668

1 files changed, 79 insertions, 1 deletions

diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index f9015b869d..947f9bf99b 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -209,6 +209,8 @@ class ErrorsTest < ActiveModel::TestCase
     person.errors.add(:name, "cannot be blank")
     person.errors.add(:name, "is invalid")
     assert person.errors.added?(:name, "cannot be blank")
+    assert person.errors.added?(:name, "is invalid")
+    assert_not person.errors.added?(:name, "incorrect")
   end
 
   test "added? returns false when no errors are present" do
@@ -222,7 +224,7 @@ class ErrorsTest < ActiveModel::TestCase
     assert_not person.errors.added?(:name, "cannot be blank")
   end
 
-  test "added? returns false when checking for an error, but not providing message arguments" do
+  test "added? returns false when checking for an error, but not providing message argument" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")
     assert_not person.errors.added?(:name)
@@ -233,6 +235,7 @@ class ErrorsTest < ActiveModel::TestCase
     person.errors.add :name, :too_long, count: 25
 
     assert person.errors.added? :name, :too_long, count: 25
+    assert person.errors.added? :name, "is too long (maximum is 25 characters)"
     assert_not person.errors.added? :name, :too_long, count: 24
     assert_not person.errors.added? :name, :too_long
     assert_not person.errors.added? :name, "is too long"
@@ -243,6 +246,81 @@ class ErrorsTest < ActiveModel::TestCase
     person = Person.new
     person.errors.add(:name, :wrong)
     assert_not person.errors.added?(:name, :used)
+    assert person.errors.added?(:name, :wrong)
+  end
+
+  test "of_kind? returns false when checking for an error, but not providing message argument" do
+    person = Person.new
+    person.errors.add(:name, "cannot be blank")
+    assert_not person.errors.of_kind?(:name)
+  end
+
+  test "of_kind? returns false when checking a nonexisting error and other errors are present for the given attribute" do
+    person = Person.new
+    person.errors.add(:name, "is invalid")
+    assert_not person.errors.of_kind?(:name, "cannot be blank")
+  end
+
+  test "of_kind? returns false when no errors are present" do
+    person = Person.new
+    assert_not person.errors.of_kind?(:name)
+  end
+
+  test "of_kind? matches the given message when several errors are present for the same attribute" do
+    person = Person.new
+    person.errors.add(:name, "cannot be blank")
+    person.errors.add(:name, "is invalid")
+    assert person.errors.of_kind?(:name, "cannot be blank")
+    assert person.errors.of_kind?(:name, "is invalid")
+    assert_not person.errors.of_kind?(:name, "incorrect")
+  end
+
+  test "of_kind? defaults message to :invalid" do
+    person = Person.new
+    person.errors.add(:name)
+    assert person.errors.of_kind?(:name)
+  end
+
+  test "of_kind? handles proc messages" do
+    person = Person.new
+    message = Proc.new { "cannot be blank" }
+    person.errors.add(:name, message)
+    assert person.errors.of_kind?(:name, message)
+  end
+
+  test "of_kind? returns true when string attribute is used with a symbol message" do
+    person = Person.new
+    person.errors.add(:name, :blank)
+    assert person.errors.of_kind?("name", :blank)
+  end
+
+  test "of_kind? handles symbol message" do
+    person = Person.new
+    person.errors.add(:name, :blank)
+    assert person.errors.of_kind?(:name, :blank)
+  end
+
+  test "of_kind? detects indifferent if a specific error was added to the object" do
+    person = Person.new
+    person.errors.add(:name, "cannot be blank")
+    assert person.errors.of_kind?(:name, "cannot be blank")
+    assert person.errors.of_kind?("name", "cannot be blank")
+  end
+
+  test "of_kind? ignores options" do
+    person = Person.new
+    person.errors.add :name, :too_long, count: 25
+
+    assert person.errors.of_kind? :name, :too_long
+    assert person.errors.of_kind? :name, "is too long (maximum is 25 characters)"
+  end
+
+  test "of_kind? returns false when checking for an error by symbol and a different error with same message is present" do
+    I18n.backend.store_translations("en", errors: { attributes: { name: { wrong: "is wrong", used: "is wrong" } } })
+    person = Person.new
+    person.errors.add(:name, :wrong)
+    assert_not person.errors.of_kind?(:name, :used)
+    assert person.errors.of_kind?(:name, :wrong)
   end
 
   test "size calculates the number of error messages" do