Add /xunit.analyzer/rules/xUnit1052

Author: bradwilson

site/toc.yml

@@ -160,6 +160,8 @@
       href: /xunit.analyzers/rules/xUnit1050
     - name: xUnit1051
       href: /xunit.analyzers/rules/xUnit1051
+    - name: xUnit1052
+      href: /xunit.analyzers/rules/xUnit1052
   - name: Assertion
     items:
     - name: xUnit2000

site/xunit.analyzers/rules/index.md

@@ -59,6 +59,7 @@ title: Roslyn Analyzer Rules
 | [xUnit1049](/xunit.analyzers/rules/xUnit1049) | ::v2::{.label .label-version-False} ::v3::{.label .label-version-True}  | ::Error::{.label .label-Error}     | Do not use 'async void' for test methods as it is no longer supported
 | [xUnit1050](/xunit.analyzers/rules/xUnit1050) | ::v2::{.label .label-version-False} ::v3::{.label .label-version-True}  | ::Info::{.label .label-Info}       | The class referenced by the ClassData attribute returns untyped data rows
 | [xUnit1051](/xunit.analyzers/rules/xUnit1051) | ::v2::{.label .label-version-False} ::v3::{.label .label-version-True}  | ::Warning::{.label .label-Warning} | Calls to methods which accept CancellationToken should use TestContext.Current.CancellationToken
+| [xUnit1052](/xunit.analyzers/rules/xUnit1052) | ::v2::{.label .label-version-False} ::v3::{.label .label-version-True}  | ::Warning::{.label .label-Warning} | Avoid using 'TheoryData<...>' with types that implement 'ITheoryDataRow'
 
 ## Assertion Analyzers (2xxx)
 

site/xunit.analyzers/rules/xUnit1052.md

@@ -0,0 +1,46 @@
+---
+analyzer: true
+title: xUnit1052
+description: Avoid using 'TheoryData<...>' with types that implement 'ITheoryDataRow'
+category: Usage
+severity: Warning
+v2: false
+v3: true
+---
+
+## Cause
+
+A violation of this rule occurs when creating a data source from `TheoryData<...>` which includes `ITheoryDataRow` (or any type which implements it).
+
+## Reason for rule
+
+`ITheoryDataRule` (and derived types, like `TheoryDataRule<...>`) are intended to be used directly from a collection, like `IEnumerable<>` or `List<>`.
+
+## How to fix violations
+
+To fix a violation of this rule, replace `TheoryData` with `IEnumeable` (or a standard generic collection).
+
+## Examples
+
+### Violates
+
+```csharp
+using Xunit;
+
+public class xUnit1052
+{
+    public static TheoryData<TheoryDataRow<int>> Data => [/*...*/];
+}
+```
+
+### Does not violate
+
+```csharp
+using System.Collections.Generic;
+using Xunit;
+
+public class xUnit1052
+{
+    public static IEnumerable<TheoryDataRow<int>> Data => [/*...*/];
+}
+```