diff --git a/Recyclable.Collections.TestData.sln b/Recyclable.Collections.TestData.sln
index e6ca371..9a66148 100644
--- a/Recyclable.Collections.TestData.sln
+++ b/Recyclable.Collections.TestData.sln
@@ -3,7 +3,9 @@ Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio Version 17
 VisualStudioVersion = 17.7.34031.279
 MinimumVisualStudioVersion = 10.0.40219.1
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Recyclable.Collections.TestData", "Recyclable.Collections.TestData\Recyclable.Collections.TestData.csproj", "{C78BEDC4-71C7-4893-B4A0-5C632E4D376E}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Recyclable.Collections.TestData", "Recyclable.Collections.TestData\Recyclable.Collections.TestData.csproj", "{C78BEDC4-71C7-4893-B4A0-5C632E4D376E}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Recyclable.Collections.TestData.xUnit", "Recyclable.Collections.TestData.xUnit\Recyclable.Collections.TestData.xUnit.csproj", "{C3217E79-86CB-451B-BBA6-04F09EFEEEBA}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -15,6 +17,10 @@ Global
 		{C78BEDC4-71C7-4893-B4A0-5C632E4D376E}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{C78BEDC4-71C7-4893-B4A0-5C632E4D376E}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{C78BEDC4-71C7-4893-B4A0-5C632E4D376E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C3217E79-86CB-451B-BBA6-04F09EFEEEBA}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C3217E79-86CB-451B-BBA6-04F09EFEEEBA}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C3217E79-86CB-451B-BBA6-04F09EFEEEBA}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C3217E79-86CB-451B-BBA6-04F09EFEEEBA}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
diff --git a/Recyclable.Collections.TestData.xUnit/BlockSizeTheoryData.cs b/Recyclable.Collections.TestData.xUnit/BlockSizeTheoryData.cs
new file mode 100644
index 0000000..e214084
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/BlockSizeTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class BlockSizeTheoryData : TheoryData<int>
+	{
+		public BlockSizeTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.BlockSizeVariants)
+			{
+				Add(testCase);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/EmptySourceDataTheoryData.cs b/Recyclable.Collections.TestData.xUnit/EmptySourceDataTheoryData.cs
new file mode 100644
index 0000000..7a92f45
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/EmptySourceDataTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class EmptySourceDataTheoryData : TheoryData<string, IEnumerable<long>, long>
+	{
+		public EmptySourceDataTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.EmptySourceDataVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/ItemsCountTheoryData.cs b/Recyclable.Collections.TestData.xUnit/ItemsCountTheoryData.cs
new file mode 100644
index 0000000..d0c494e
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/ItemsCountTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class ItemsCountTheoryData : TheoryData<long>
+	{
+		public ItemsCountTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.ItemsCountVariants)
+			{
+				Add(testCase);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/ItemsCountWithBlockSizeTheoryData.cs b/Recyclable.Collections.TestData.xUnit/ItemsCountWithBlockSizeTheoryData.cs
new file mode 100644
index 0000000..0f9f856
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/ItemsCountWithBlockSizeTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class ItemsCountWithBlockSizeTheoryData : TheoryData<long, int>
+	{
+		public ItemsCountWithBlockSizeTheoryData()
+		{
+			foreach (var (ItemsCount, BlockSize) in RecyclableLongListTestData.TargetDataVariants)
+			{
+				Add(ItemsCount, BlockSize);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/README.md b/Recyclable.Collections.TestData.xUnit/README.md
new file mode 100644
index 0000000..47e7755
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/README.md
@@ -0,0 +1,18 @@
+# Recyclable.Collections.TestData.xUnit
+`Recyclable.Collections.TestData.xUnit` project is a basic open source package for working with repeatable xUnit test data useful for testing collections like `RecyclableList&lt;T&gt;`, `RecyclableLongList&lt;T&gt;`, `List&lt;T&gt;`, `SortableList&lt;T&gt;`, `PriorityQueue&lt;T&gt;` &amp; similar.
+
+## Included
+* `BlockSizeTheoryData: TheoryData<int BlockSize>`
+* `EmptySourceDataTheoryData: TheoryData<string TestCase, IEnumerable<long> TestData, long ItemsCount>`
+* `ItemsCountTheoryData: TheoryData<long ItemsCount>`
+* `ItemsCountWithBlockSizeTheoryData: TheoryData<long ItemsCount, int BlockSize>`
+* `SourceDataTheoryData: TheoryData<string TestCase, IEnumerable<long> TestData, long ItemsCount>`
+* `SourceDataWithBlockSizeTheoryData: TheoryData<string TestCase, IEnumerable<long> TestData, long ItemsCount, int BlockSize>`
+* `SourceDataWithBlockSizeWithItemIndexTheoryData: TheoryData<string TestCase, IEnumerable<long> TestData, long ItemsCount, int BlockSize, IEnumerable<long> ItemIndexes>`
+* `SourceDataWithBlockSizeWithItemIndexWithRangeTheoryData: TheoryData<string TestCase, IEnumerable<long> TestData, long ItemsCount, int BlockSize, IEnumerable<(long ItemIndex, long RangeItemsCount)> ItemRanges>`
+* `SourceDataWithItemIndexTheoryData: TheoryData<string TestCase, IEnumerable<long> TestData, long ItemsCount, IEnumerable<long> ItemIndexes>`
+* `SourceRefDataTheoryData: TheoryData<string TestCase, IEnumerable<object> TestData, long ItemsCount>`
+* `SourceRefDataWithBlockSizeTheoryData: TheoryData<string TestCase, IEnumerable<object> TestData, long ItemsCount, int BlockSize>`
+* `SourceRefDataWithBlockSizeWithItemIndexTheoryData: TheoryData<string TestCase, IEnumerable<object> TestData, long ItemsCount, int BlockSize, IEnumerable<long> ItemIndexes>`
+* `SourceRefDataWithBlockSizeWithItemIndexWithRangeTheoryData: TheoryData<string TestCase, IEnumerable<object> TestData, long ItemsCount, int BlockSize, IEnumerable<(long ItemIndex, long RangeItemsCount)> ItemRanges>`
+* `SourceRefDataWithItemIndexTheoryData: TheoryData<string TestCase, IEnumerable<object> TestData, long ItemsCount, IEnumerable<long> ItemIndexes>`
diff --git a/Recyclable.Collections.TestData.xUnit/Recyclable.Collections.TestData.xUnit.csproj b/Recyclable.Collections.TestData.xUnit/Recyclable.Collections.TestData.xUnit.csproj
new file mode 100644
index 0000000..fb59ef9
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/Recyclable.Collections.TestData.xUnit.csproj
@@ -0,0 +1,44 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+	<PropertyGroup>
+		<TargetFrameworks>net6.0;net7.0</TargetFrameworks>
+		<ImplicitUsings>enable</ImplicitUsings>
+		<Nullable>enable</Nullable>
+		<OutputType>Library</OutputType>
+		<GeneratePackageOnBuild>true</GeneratePackageOnBuild>
+		<PackageId>Recyclable.Collections.TestData.xUnit</PackageId>
+		<PackageVersion>0.0.0.1</PackageVersion>
+		<Authors>Marek Lemańczyk</Authors>
+		<Company>N/A</Company>
+		<Product>Recyclable.Collections.TestData.xUnit</Product>
+		<PackageTags>Recyclable Array Pool List Sortable Sort Benchmark Benchmarks Collection Collections Test Data xUnit</PackageTags>
+		<Description>`Recyclable.Collections.TestData.xUnit` project is a basic open source package for working with repeatable xUnit test data useful for testing collections like `RecyclableList&lt;T&gt;`, `RecyclableLongList&lt;T&gt;`, `List&lt;T&gt;`, `SortableList&lt;T&gt;`, `PriorityQueue&lt;T&gt;` &amp; similar.</Description>
+		<PackageProjectUrl>https://github.com/mlemanczyk/Recyclable.Collections.TestData</PackageProjectUrl>
+		<RepositoryUrl>https://github.com/mlemanczyk/Recyclable.Collections.TestData.xUnit</RepositoryUrl>
+		<Copyright>Marek Lemańczyk 2023</Copyright>
+		<PackageLicenseFile>LICENSE.md</PackageLicenseFile>
+		<PackageReadmeFile>README.md</PackageReadmeFile>
+		<RepositoryType>git</RepositoryType>
+		<PackageReleaseNotes>Initial version implemented.</PackageReleaseNotes>
+		<Platforms>AnyCPU;x64</Platforms>
+		<PackageIcon>logo.png</PackageIcon>
+	</PropertyGroup>
+
+	<ItemGroup>
+		<Content Include="..\logo.png" Pack="true" PackagePath="" Link="logo.png" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<None Include="..\LICENSE.md" Pack="true" PackagePath="" Link="LICENSE.md" />
+		<None Include="README.md" Pack="true" PackagePath="" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<PackageReference Include="Microsoft.Extensions.ObjectPool" Version="8.0.0" />
+		<PackageReference Include="Open.Numeric.Primes" Version="3.1.0" />
+		<PackageReference Include="Recyclable.Collections" Version="0.0.6.1" />
+		<PackageReference Include="Recyclable.Collections.TestData" Version="0.0.3.4" />
+		<PackageReference Include="xunit.extensibility.core" Version="2.6.4" />
+	</ItemGroup>
+
+</Project>
diff --git a/Recyclable.Collections.TestData.xUnit/SourceDataTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceDataTheoryData.cs
new file mode 100644
index 0000000..3de2306
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceDataTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceDataTheoryData : TheoryData<string, IEnumerable<long>, long>
+	{
+		public SourceDataTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceDataVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/SourceDataWithBlockSizeTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceDataWithBlockSizeTheoryData.cs
new file mode 100644
index 0000000..140b8c5
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceDataWithBlockSizeTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceDataWithBlockSizeTheoryData : TheoryData<string, IEnumerable<long>, long, int>
+	{
+		public SourceDataWithBlockSizeTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceDataWithBlockSizeVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount, testCase.BlockSize);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/SourceDataWithBlockSizeWithItemIndexTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceDataWithBlockSizeWithItemIndexTheoryData.cs
new file mode 100644
index 0000000..7287bf9
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceDataWithBlockSizeWithItemIndexTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceDataWithBlockSizeWithItemIndexTheoryData : TheoryData<string, IEnumerable<long>, long, int, IEnumerable<long>>
+	{
+		public SourceDataWithBlockSizeWithItemIndexTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceDataWithBlockSizeWithItemIndexVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount, testCase.BlockSize, testCase.ItemIndexes);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/SourceDataWithBlockSizeWithItemIndexWithRangeTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceDataWithBlockSizeWithItemIndexWithRangeTheoryData.cs
new file mode 100644
index 0000000..9cd9812
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceDataWithBlockSizeWithItemIndexWithRangeTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceDataWithBlockSizeWithItemIndexWithRangeTheoryData : TheoryData<string, IEnumerable<long>, long, int, IEnumerable<(long, long)>>
+	{
+		public SourceDataWithBlockSizeWithItemIndexWithRangeTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceDataWithBlockSizeWithItemIndexWithRangeVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount, testCase.BlockSize, testCase.ItemsIndexesWithRange);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/SourceDataWithItemIndexTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceDataWithItemIndexTheoryData.cs
new file mode 100644
index 0000000..7cf25b2
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceDataWithItemIndexTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceDataWithItemIndexTheoryData : TheoryData<string, IEnumerable<long>, long, IEnumerable<long>>
+	{
+		public SourceDataWithItemIndexTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceDataWithItemIndexVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount, testCase.ItemIndexes);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/SourceRefDataTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceRefDataTheoryData.cs
new file mode 100644
index 0000000..6a14528
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceRefDataTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceRefDataTheoryData : TheoryData<string, IEnumerable<object>, long>
+	{
+		public SourceRefDataTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceRefDataVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/SourceRefDataWithBlockSizeTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceRefDataWithBlockSizeTheoryData.cs
new file mode 100644
index 0000000..8b4105b
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceRefDataWithBlockSizeTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceRefDataWithBlockSizeTheoryData : TheoryData<string, IEnumerable<object>, long, int>
+	{
+		public SourceRefDataWithBlockSizeTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceRefDataWithBlockSizeVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount, testCase.BlockSize);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/SourceRefDataWithBlockSizeWithItemIndexTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceRefDataWithBlockSizeWithItemIndexTheoryData.cs
new file mode 100644
index 0000000..344fc90
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceRefDataWithBlockSizeWithItemIndexTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceRefDataWithBlockSizeWithItemIndexTheoryData : TheoryData<string, IEnumerable<object>, long, int, IEnumerable<long>>
+	{
+		public SourceRefDataWithBlockSizeWithItemIndexTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceRefDataWithBlockSizeWithItemIndexVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount, testCase.BlockSize, testCase.ItemIndexes);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/SourceRefDataWithBlockSizeWithItemIndexWithRangeTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceRefDataWithBlockSizeWithItemIndexWithRangeTheoryData.cs
new file mode 100644
index 0000000..70e5f02
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceRefDataWithBlockSizeWithItemIndexWithRangeTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceRefDataWithBlockSizeWithItemIndexWithRangeTheoryData : TheoryData<string, IEnumerable<object>, long, int, IEnumerable<(long, long)>>
+	{
+		public SourceRefDataWithBlockSizeWithItemIndexWithRangeTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceRefDataWithBlockSizeWithItemIndexWithRangeVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount, testCase.BlockSize, testCase.ItemsIndexesWithRange);
+			}
+		}
+	}
+}
diff --git a/Recyclable.Collections.TestData.xUnit/SourceRefDataWithItemIndexTheoryData.cs b/Recyclable.Collections.TestData.xUnit/SourceRefDataWithItemIndexTheoryData.cs
new file mode 100644
index 0000000..90e4100
--- /dev/null
+++ b/Recyclable.Collections.TestData.xUnit/SourceRefDataWithItemIndexTheoryData.cs
@@ -0,0 +1,15 @@
+using Xunit;
+
+namespace Recyclable.Collections.TestData.xUnit
+{
+	public class SourceRefDataWithItemIndexTheoryData : TheoryData<string, IEnumerable<object>, long, IEnumerable<long>>
+	{
+		public SourceRefDataWithItemIndexTheoryData()
+		{
+			foreach (var testCase in RecyclableLongListTestData.SourceRefDataWithItemIndexVariants)
+			{
+				Add(testCase.TestCase, testCase.TestData, testCase.ItemsCount, testCase.ItemIndexes);
+			}
+		}
+	}
+}