TerminalVelocity: if -Output is a directory the filename is derived from the input filename in -Path. Updated docs stating TV code file basenames MUST match source (.xml) filenames e.g. Foo\Bar.xml should only produce Bar.cpp (or Bar.cs). (#5111)

Author: DrusTheAxe

docs/Coding-Guidelines/TerminalVelocity.md

@@ -82,7 +82,7 @@ Run the TerminalVelocity generator to create a header file for your feature defi
 For example:
 
 ```
-tools\TerminalVelocity\Generate-TerminalVelocityFeatures.cmd -Path dev\common\TerminalVelocityFeatures-DeploymentAPI.xml -Namespace Microsoft.Windows.DeploymentAPI -Output dev\common\TerminalVelocityFeatures-DeploymentAPI.h
+tools\TerminalVelocity\Generate-TerminalVelocityFeatures.cmd -Channel Experimental -Language C++ -Namespace Microsoft.Windows.ApplicationModel.WindowsAppRuntime -Path dev\common\TerminalVelocityFeatures-DeploymentAPI.xml -Output dev\common
 ```
 
 Generate-TerminalVelocityFeatures.cmd runs the generator. The following parameters are supported:
@@ -91,7 +91,9 @@ Generate-TerminalVelocityFeatures.cmd runs the generator. The following paramete
 * **-Channel <channel>** -- channel being built. Allowed values: [`Experimental`, `Preview`, `Stable`, `WindowsInbox`]. Optional, default=`Experimental`.
 * **-Language <language>** -- language for generated code. Allowed values: [`C++`, `C#`]. Optional, default=`C++`.
 * **-Namespace <namespace>** -- namespace for generated symbols. The parameter can specify multiple namespaces delimited by `.` or `::` (the generator emits the right syntax for the target language regardless of the parameter's notation). Optional.
-* **-Output <filename>** -- file to write the generated output. Optional, default=stdout.
+* **-Output <filename>** -- file to write the generated output. Optional, default=stdout. If `filename` is a directory the filename is generated from the input filename (-Path) in the specified directory.
+
+WARNING: As a matter of policy output files MUST have the same base name as the input file (-Path).
 
 For help run
 
@@ -109,7 +111,7 @@ Add a build task to run the TerminalVelocity with the build's properties. For ex
     inputs:
       targetType: filePath
       filePath: tools\TerminalVelocity\Generate-TerminalVelocityFeatures.ps1
-      arguments: -Path $(Build.SourcesDirectory)\dev\common\TerminalVelocityFeatures-DeploymentAPI.xml -Channel ${{ parameters.channel }} -Language C++ -Namespace Microsoft.Windows.ApplicationModel.WindowsAppSDK -Output $(Build.SourcesDirectory)\dev\common\TerminalVelocityFeatures-DeploymentAPI.h
+      arguments: -Path $(Build.SourcesDirectory)\dev\common\TerminalVelocityFeatures-DeploymentAPI.xml -Channel ${{ parameters.channel }} -Language C++ -Namespace Microsoft.Windows.ApplicationModel.WindowsAppSDK -Output $(Build.SourcesDirectory)\dev\common
       workingDirectory: '$(Build.SourcesDirectory)'
 ```
 

tools/TerminalVelocity/Generate-TerminalVelocityFeatures.ps1

@@ -15,7 +15,7 @@
     The target channel for Feature checks (default=Experimental).
 
 .PARAMETER Output
-    File to create (default=stdout).
+    File to create (default=stdout). If a directory the filename is derived from the input filename (-Path) and the language.
 
 .PARAMETER Language
     Programming language to generate (default=C++).
@@ -67,6 +67,17 @@ if ([String]::IsNullOrEmpty($Namespace))
     }
 }
 
+# Generate the output base name derived from input base name and language if the input filename (-Path) is a directory
+$Output_Original = $Output
+if (Test-Path -Path $Output -PathType Container)
+{
+    $path_filename = Split-Path -Path $Path -Leaf
+    $path_basename = $path_filename -replace '\.[^.]*$', ''
+    $extension = @{ 'C++'='.h'; 'C#'='.cs' }[$Language]
+    $filename = $path_basename + $extension
+    $Output = Join-Path $Output $filename
+}
+
 Enum State
 {
     AlwaysDisabled;
@@ -96,7 +107,7 @@ Class Feature
         $this.Name = $entry.name
         $this.State = ConvertTo-FeatureState $entry.state
 
-        # TODO: Remove the temp workaround of downgrading to StrictModel 1.0 once b#52128443 is fixed. 
+        # TODO: Remove the temp workaround of downgrading to StrictModel 1.0 once b#52128443 is fixed.
         Set-StrictMode -Version 1.0
         $this.Id = $entry.id
         $this.ChannelTokenStates = [System.Collections.Generic.Dictionary[string, State]]::new()
@@ -206,7 +217,7 @@ $comment_line_prefix Licensed under the MIT License.
 $comment_line_prefix THIS FILE IS AUTOMATICALLY GENERATED; DO NOT EDIT IT
 
 $comment_line_prefix INPUT FILE: $Path
-$comment_line_prefix OPTIONS: -Channel $Channel -Language $Language$(if (-not ([String]::IsNullOrEmpty($Namespace))) { " -Namespace $Namespace" }) -Path $Path$(if (-not ([String]::IsNullOrEmpty($Output))) { " -Output $Output" })
+$comment_line_prefix OPTIONS: -Channel $Channel -Language $Language$(if (-not ([String]::IsNullOrEmpty($Namespace))) { " -Namespace $Namespace" }) -Path $Path$(if (-not ([String]::IsNullOrEmpty($Output))) { " -Output $Output_Original" })
 
 
 "@