Also adding file tests

Adding Test Files for .ps1 and .psm1

testdata/expected/file.ps1

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+<#
+ Copyright 2025 Google LLC
+
+ 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.
+#>
+
+Write-Output "Hello World"

testdata/expected/file.psm1

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+<#
+ Copyright 2025 Google LLC
+
+ 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.
+#>
+
+function Get-HelloWorld {
+    <#
+    .SYNOPSIS
+        Outputs a "Hello, World!" message.
+
+    .DESCRIPTION
+        This function is a basic example to demonstrate how to create a PowerShell module.
+
+    .EXAMPLE
+        PS> Get-HelloWorld
+        Hello, World!
+
+    .NOTES
+        This is a demo function.
+    #>
+    Write-Output "Hello, World!"
+}
+
+# Export the function to make it available when the module is imported.
+Export-ModuleMember -Function Get-HelloWorld

testdata/initial/file.ps1

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+Write-Output "Hello World"

testdata/initial/file.psm1

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+function Get-HelloWorld {
+    <#
+    .SYNOPSIS
+        Outputs a "Hello, World!" message.
+
+    .DESCRIPTION
+        This function is a basic example to demonstrate how to create a PowerShell module.
+
+    .EXAMPLE
+        PS> Get-HelloWorld
+        Hello, World!
+
+    .NOTES
+        This is a demo function.
+    #>
+    Write-Output "Hello, World!"
+}
+
+# Export the function to make it available when the module is imported.
+Export-ModuleMember -Function Get-HelloWorld