feat: add submissionCanceled status (#42)

Author: marcossevilla

lib/formz.dart

@@ -18,14 +18,18 @@ enum FormzStatus {
   submissionSuccess,
 
   /// The form submission failed.
-  submissionFailure
+  submissionFailure,
+
+  /// The form submission has been canceled.
+  submissionCanceled
 }
 
 const _validatedFormzStatuses = <FormzStatus>{
   FormzStatus.valid,
   FormzStatus.submissionInProgress,
   FormzStatus.submissionSuccess,
   FormzStatus.submissionFailure,
+  FormzStatus.submissionCanceled,
 };
 
 /// Useful extensions on [FormzStatus]
@@ -55,6 +59,9 @@ extension FormzStatusX on FormzStatus {
 
   /// Indicates whether the form submission failed.
   bool get isSubmissionFailure => this == FormzStatus.submissionFailure;
+
+  /// Indicates whether the form submission has been canceled.
+  bool get isSubmissionCanceled => this == FormzStatus.submissionCanceled;
 }
 
 /// Enum representing the status of a form input at any given point in time.

test/formz_test.dart

@@ -199,6 +199,7 @@ void main() {
         expect(FormzStatus.submissionInProgress.isValidated, isTrue);
         expect(FormzStatus.submissionFailure.isValidated, isTrue);
         expect(FormzStatus.submissionSuccess.isValidated, isTrue);
+        expect(FormzStatus.submissionCanceled.isValidated, isTrue);
       });
 
       test('isInvalid returns true', () {
@@ -216,6 +217,10 @@ void main() {
       test('isSubmissionSuccess returns true', () {
         expect(FormzStatus.submissionSuccess.isSubmissionSuccess, isTrue);
       });
+
+      test('isSubmissionCanceled returns true', () {
+        expect(FormzStatus.submissionCanceled.isSubmissionCanceled, isTrue);
+      });
     });
   });
 }