Add UseUsingScopeModifierInNewRunspaces rule

RuleDocumentation/README.md

@@ -16,6 +16,7 @@
 |[AvoidOverwritingBuiltInCmdlets](./AvoidOverwritingBuiltInCmdlets.md) | Warning | |
 |[AvoidNullOrEmptyHelpMessageAttribute](./AvoidNullOrEmptyHelpMessageAttribute.md) | Warning | |
 |[AvoidShouldContinueWithoutForce](./AvoidShouldContinueWithoutForce.md) | Warning | |
+|[UseUsingScopeModifierInNewRunspaces](./UseUsingScopeModifierInNewRunspaces.md) | Warning | |
 |[AvoidUsingCmdletAliases](./AvoidUsingCmdletAliases.md) | Warning | Yes |
 |[AvoidUsingComputerNameHardcoded](./AvoidUsingComputerNameHardcoded.md) | Error | |
 |[AvoidUsingConvertToSecureStringWithPlainText](./AvoidUsingConvertToSecureStringWithPlainText.md) | Error | |

RuleDocumentation/UseUsingScopeModifierInNewRunspaces.md

@@ -0,0 +1,65 @@
+# UseUsingScopeModifierInNewRunspaces
+
+**Severity Level: Warning**
+
+## Description
+
+If a ScriptBlock is intended to be run in a new RunSpace, variables inside it should use $using: scope modifier, or be initialized within the ScriptBlock.
+This applies to:
+
+- Invoke-Command *
+- Workflow { InlineScript {}}
+- Foreach-Object **
+- Start-Job
+- Start-ThreadJob
+- The `Script` resource in DSC configurations, specifically for the `GetScript`, `TestScript` and `SetScript` properties
+
+\* Only with the -ComputerName or -Session parameter.  
+\*\* Only with the -Parallel parameter
+
+## How to Fix
+
+Within the ScriptBlock, instead of just using a variable from the parent scope, you have to add the `using:` scope modifier to it.
+
+## Example
+
+### Wrong
+
+```PowerShell
+$var = "foo"
+1..2 | ForEach-Object -Parallel { $var }
+```
+
+### Correct
+
+```PowerShell
+$var = "foo"
+1..2 | ForEach-Object -Parallel { $using:var }
+```
+
+## More correct examples
+
+```powershell
+$bar = "bar"
+Invoke-Command -ComputerName "foo" -ScriptBlock { $using:bar }
+```
+
+```powershell
+$bar = "bar"
+$s = New-PSSession -ComputerName "foo"
+Invoke-Command -Session $s -ScriptBlock { $using:bar }
+```
+
+```powershell
+# Remark: Workflow is supported on Windows PowerShell only
+Workflow { 
+    $foo = "foo"
+    InlineScript { $using:foo }
+}
+```
+
+```powershell
+$foo = "foo"
+Start-ThreadJob -ScriptBlock { $using:foo }
+Start-Job -ScriptBlock {$using:foo }
+```

Rules/Strings.resx

@@ -1114,12 +1114,27 @@
     <value>ReviewUnusedParameter</value>
   </data>
   <data name="ReviewUnusedParameterDescription" xml:space="preserve">
-    <value>Ensure all parameters are used within the same script, scriptblock, or function where they are declared.</value>	
-  </data>	
-  <data name="ReviewUnusedParameterError" xml:space="preserve">	
-    <value>The parameter '{0}' has been declared but not used. </value>	
-  </data>	
-  <data name="ReviewUnusedParameterName" xml:space="preserve">	
-    <value>ReviewUnusedParameter</value>	
-  </data>
-</root>
+    <value>Ensure all parameters are used within the same script, scriptblock, or function where they are declared.</value>
+  </data>
+  <data name="ReviewUnusedParameterError" xml:space="preserve">
+    <value>The parameter '{0}' has been declared but not used. </value>
+  </data>
+  <data name="ReviewUnusedParameterName" xml:space="preserve">
+    <value>ReviewUnusedParameter</value>
+  </data>
+  <data name="UseUsingScopeModifierInNewRunspacesCommonName" xml:space="preserve">
+    <value>Use 'Using:' scope modifier in RunSpace ScriptBlocks</value>
+  </data>
+  <data name="UseUsingScopeModifierInNewRunspacesDescription" xml:space="preserve">
+    <value>If a ScriptBlock is intended to be run as a new RunSpace, variables inside it should use 'Using:' scope modifier, or be initialized within the ScriptBlock.</value>
+  </data>
+  <data name="UseUsingScopeModifierInNewRunspacesName" xml:space="preserve">
+    <value>UseUsingScopeModifierInNewRunspaces</value>
+  </data>
+  <data name="UseUsingScopeModifierInNewRunspacesError" xml:space="preserve">
+    <value>The variable '{0}' is not declared within this ScriptBlock, and is missing the 'Using:' scope modifier.</value>
+  </data>
+  <data name="UseUsingScopeModifierInNewRunspacesCorrectionDescription" xml:space="preserve">
+    <value>Replace {0} with {1}</value>
+  </data>
+</root>