Usage Analyzers
ID	Title
xUnit1000 Error	Test classes must be public
xUnit1001 Error	Fact methods cannot have parameters
xUnit1002 Error	Test methods cannot have multiple Fact or Theory attributes
xUnit1003 Error	Theory methods must have test data
xUnit1004 Info	Test methods should not be skipped
xUnit1005 Warning	Fact methods should not have test data
xUnit1006 Warning	Theory methods should have parameters
xUnit1007 Error	ClassData must point at a valid class
xUnit1008 Warning	Test data attribute should only be used on a Theory
xUnit1009 Error	InlineData values must match the number of method parameters
xUnit1010 Error	The value is not convertible to the method parameter type
xUnit1011 Error	There is no matching method parameter
xUnit1012 Warning	Null should not be used for value type parameters
xUnit1013 Warning	Public method should be marked as test
xUnit1014 Warning	MemberData should use nameof operator for member name
xUnit1015 Error	MemberData must reference an existing member
xUnit1016 Error	MemberData must reference a public member
xUnit1017 Error	MemberData must reference a static member
xUnit1018 Error	MemberData must reference a valid member kind
xUnit1019 Error	MemberData must reference a member providing a valid data type
xUnit1020 Error	MemberData must reference a property with a getter
xUnit1021 Warning	MemberData should not have parameters if the referenced member is not a method
xUnit1022 Error	Theory methods cannot have a parameter array
xUnit1023 Error	Theory methods cannot have default parameter values
xUnit1024 Error	Test methods cannot have overloads
xUnit1025 Warning	InlineData should be unique within the Theory it belongs to
xUnit1026 Warning	Theory methods should use all of their parameters
xUnit1027 Error	Collection definition classes must be public
xUnit1028 Error	Test method must have valid return type
xUnit1029 Error	Local functions cannot be test functions
xUnit1030 Warning	Do not call ConfigureAwait in test method
xUnit1031 Warning	Do not use blocking task operations in test method
xUnit1032 Error	Test classes cannot be nested within a generic class
xUnit1033 Info	Test classes decorated with 'Xunit.IClassFixture' or 'Xunit.ICollectionFixture' should add a constructor argument of type TFixture
xUnit1034 Warning	Null should only be used for nullable parameters
xUnit1035 Error	The value is not convertible to the method parameter type
xUnit1036 Error	There is no matching method parameter
xUnit1037 Error	There are fewer TheoryData type arguments than required by the parameters of the test method
xUnit1038 Error	There are more TheoryData type arguments than allowed by the parameters of the test method
xUnit1039 Error	The type argument to TheoryData is not compatible with the type of the corresponding test method parameter
xUnit1040 Warning	The type argument to TheoryData is nullable, while the type of the corresponding test method parameter is not
xUnit1041 Warning	Fixture arguments to test classes must have fixture sources
xUnit1042 Info	The member referenced by the MemberData attribute returns untyped data rows
xUnit1043 Error	Constructors on classes derived from FactAttribute must be public when used on test methods
xUnit1044 Info	Avoid using TheoryData type arguments that are not serializable
xUnit1045 Info	Avoid using TheoryData type arguments that might not be serializable
xUnit1046 Info	Avoid using TheoryDataRow arguments that are not serializable
xUnit1047 Info	Avoid using TheoryDataRow arguments that might not be serializable
xUnit1048 Warning	Avoid using 'async void' for test methods as it is deprecated in xUnit.net v3
xUnit1049 Error	Do not use 'async void' for test methods as it is no longer supported
Assertion Analyzers
ID	Title
xUnit2000 Warning	Constants and literals should be the expected argument
xUnit2001 Hidden	Do not use invalid equality check
xUnit2002 Warning	Do not use null check on value type
xUnit2003 Warning	Do not use equality check to test for null value
xUnit2004 Warning	Do not use equality check to test for boolean conditions
xUnit2005 Warning	Do not use identity check on value type
xUnit2006 Warning	Do not use invalid string equality check
xUnit2007 Warning	Do not use typeof expression to check the type
xUnit2008 Warning	Do not use boolean check to match on regular expressions
xUnit2009 Warning	Do not use boolean check to check for substrings
xUnit2010 Warning	Do not use boolean check to check for string equality
xUnit2011 Warning	Do not use empty collection check
xUnit2012 Warning	Do not use Enumerable.Any() to check if a value exists in a collection
xUnit2013 Warning	Do not use equality check to check for collection size.
xUnit2014 Error	Do not use throws check to check for asynchronously thrown exception
xUnit2015 Warning	Do not use typeof expression to check the exception type
xUnit2016 Error	Keep precision in the allowed range when asserting equality of doubles or decimals.
xUnit2017 Warning	Do not use Contains() to check if a value exists in a collection
xUnit2018 Warning	Do not compare an object's exact type to an abstract class or interface
xUnit2019 Hidden	Do not use obsolete throws check to check for asynchronously thrown exception
xUnit2020 Warning	Do not use always-failing boolean assertion to fail a test
xUnit2021 Error	Async assertions should be awaited
xUnit2022 Info	Boolean assertions should not be negated
xUnit2023 Info	Do not use collection methods for single-item collections
xUnit2024 Info	Do not use boolean asserts for simple equality tests
xUnit2025 Info	The boolean assertion statement can be simplified
xUnit2026 Warning	Comparison of sets must be done with IEqualityComparer
xUnit2027 Warning	Comparison of sets to linear containers have undefined results
xUnit2028 Warning	Do not use Assert.Empty or Assert.NotEmpty with problematic types
Extensibility Analyzers
ID	Title
xUnit3000 Error	Classes which cross AppDomain boundaries must derive directly or indirectly from LongLivedMarshalByRefObject
xUnit3001 Error	Classes that implement Xunit.Abstractions.IXunitSerializable must have a public parameterless constructor

Copyright © .NET Foundation. Contributions welcomed at https://github.com/xunit/xunit/tree/gh-pages.