Remove broken support for comparing unrelated types.

src/FluentValidation.Tests/FluentValidation.Tests.csproj

@@ -20,9 +20,7 @@
     <PackageReference Include="xunit.runner.visualstudio" Version="2.2.0" />
     <PackageReference Include="xunit" Version="2.2.0" />
     <PackageReference Include="Moq" Version="4.7.99" />
-    <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies"
-                      Version="1.0.0"
-                      PrivateAssets="All" />
+    <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.0-preview.2" PrivateAssets="All" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\FluentValidation\FluentValidation.csproj" />

src/FluentValidation.Tests/LessThanOrEqualToValidatorTester.cs

@@ -1,18 +1,18 @@
 #region License
 // Copyright (c) Jeremy Skinner (http://www.jeremyskinner.co.uk)
-// 
-// Licensed under the Apache License, Version 2.0 (the "License"); 
-// you may not use this file except in compliance with the License. 
-// You may obtain a copy of the License at 
-// 
-// http://www.apache.org/licenses/LICENSE-2.0 
-// 
-// Unless required by applicable law or agreed to in writing, software 
-// distributed under the License is distributed on an "AS IS" BASIS, 
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
-// See the License for the specific language governing permissions and 
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
 // limitations under the License.
-// 
+//
 // The latest version of this file can be found at https://github.com/jeremyskinner/FluentValidation
 #endregion
 
@@ -25,7 +25,7 @@ namespace FluentValidation.Tests {
 	using Xunit;
 	using Validators;
 
-	
+
 	public class LessThanOrEqualToValidatorTester {
 		private TestValidator validator;
 		private const int value = 1;
@@ -47,11 +47,6 @@ public class LessThanOrEqualToValidatorTester {
 			result.IsValid.ShouldBeTrue();
 		}
 
-		[Fact]
-		public void Should_succeed_when_less_than_input_using_different_types() {
-			new LessThanOrEqualValidator(100M).IsValid(20D, 100M).ShouldBeTrue();
-		}
-
 		[Fact]
 		public void Should_succeed_when_equal_to_input() {
 			var result = validator.Validate(new Person{Id=value});
@@ -134,4 +129,4 @@ public class LessThanOrEqualToValidatorTester {
             result.IsValid.ShouldBeFalse();
         }
 	}
-}
+}

src/FluentValidation.Tests/LessThanValidatorTester.cs

@@ -79,11 +79,6 @@ public class LessThanValidatorTester {
 			);
 		}
 
-		[Fact]
-		public void Should_not_throw_when_value_to_compare_is_of_different_type() {
-		    new LessThanValidator(10M).IsValid(5M, 10).ShouldBeTrue();
-		}
-
 		[Fact]
 		public void Extracts_property_from_expression() {
 			var validator = new TestValidator(v => v.RuleFor(x => x.Id).LessThan(x => x.AnotherInt));

src/FluentValidation/FluentValidation.csproj

@@ -6,23 +6,19 @@
 FluentValidation 9 is a major release. Please read the upgrade notes at https://docs.fluentvalidation.net/en/latest/upgrading-to-9.html
 
 Changes in 9.0.0:
-* Removed support for netstandard1.1, netstandard1.6 and net45 (net461 still supported)
+* Removed support for netstandard1.1 and netstandard1.6
 * Default email validation mode now uses the same logic as ASP.NET Core. Previous regex behaviour is opt-in.
 * TestHelper advanced mode now has more features (see https://docs.fluentvalidation.net/en/latest/testing.html#advanced-test-extensions)
 * Equal/NotEqual now perform ordinal comparison when used with string properties
 * Severity can now be set dynamically with a callback
 * Removed WithLocalizedMessage (WithMessage that takes a callback is the replacement)
 * Removed ResourceName from ValidationFailure
 * Removed ResourceName and ResourceType from IStringSource.
-* Removed SetCollectionValidator which was deprecated in 8.0 
-* Removed DelegatingValidator which was deprecated in 8.x.
+* Removed SetCollectionValidator which was deprecated in 8.0
 * Additional overload of OnAnyFailure that can receive a collection of validation failures
 * Remove DisplayAttribute integration and reference to DataAnnotations.
 * ComparisonProperty placeholder is now formatted like PropertyName
 * Translations of default error messages into other languages are now lazily-loaded
-* PropertyValidator.ShouldValidateAsync reanamed to ShouldValidateAsynchronously to remove confusion where the naming suggested this was an async method
-* PropertyValidatorContext.Instance renamed to InstanceToValidate for consistency with ValidationContext.
-* Removed various methods from MessageFormatter that were deprecated in 8.x
 
 Full release notes can be found at https://github.com/JeremySkinner/FluentValidation/blob/master/Changelog.txt
 		</PackageReleaseNotes>
@@ -40,8 +36,6 @@ Full release notes can be found at https://github.com/JeremySkinner/FluentValida
     <Compile Include="..\CommonAssemblyInfo.cs" Link="CommonAssemblyInfo.cs" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies"
-                      Version="1.0.0"
-                      PrivateAssets="All" />
+    <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.0-preview.2" PrivateAssets="All" />
   </ItemGroup>
 </Project>

src/FluentValidation/Validators/ExclusiveBetweenValidator.cs

@@ -1,18 +1,18 @@
 #region License
 // Copyright (c) Jeremy Skinner (http://www.jeremyskinner.co.uk)
-// 
-// Licensed under the Apache License, Version 2.0 (the "License"); 
-// you may not use this file except in compliance with the License. 
-// You may obtain a copy of the License at 
-// 
-// http://www.apache.org/licenses/LICENSE-2.0 
-// 
-// Unless required by applicable law or agreed to in writing, software 
-// distributed under the License is distributed on an "AS IS" BASIS, 
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
-// See the License for the specific language governing permissions and 
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
 // limitations under the License.
-// 
+//
 // The latest version of this file can be found at https://github.com/jeremyskinner/FluentValidation
 #endregion
 
@@ -26,7 +26,7 @@ public class ExclusiveBetweenValidator : PropertyValidator, IBetweenValidator {
 			To = to;
 			From = from;
 
-			if (Comparer.GetComparisonResult(to, from) == -1) {
+			if (to.CompareTo(from) == -1) {
 				throw new ArgumentOutOfRangeException(nameof(to), "To should be larger than from.");
 			}
 		}
@@ -41,7 +41,7 @@ public class ExclusiveBetweenValidator : PropertyValidator, IBetweenValidator {
 			// This should not be a failure condition - only a NotNull/NotEmpty should cause a null to fail.
 			if (propertyValue == null) return true;
 
-			if (Comparer.GetComparisonResult(propertyValue, From) <= 0 || Comparer.GetComparisonResult(propertyValue, To) >= 0) {
+			if (propertyValue.CompareTo(From) <= 0 || propertyValue.CompareTo(To) >= 0) {
 
 				context.MessageFormatter
 					.AppendArgument("From", From)
@@ -53,4 +53,4 @@ public class ExclusiveBetweenValidator : PropertyValidator, IBetweenValidator {
 			return true;
 		}
 	}
-}
+}