Use MultiTarget values defined in Source project when not defined in Sample project

Author: Arlodotexe

MultiTarget/GenerateAllProjectReferences.ps1

@@ -1,25 +1,46 @@
 Param (
-  [Parameter(HelpMessage = "The directory where props files for discovered projects should be saved.")] 
-  [string]$projectPropsOutputDir = "$PSScriptRoot/Generated",
-
-  [Parameter(HelpMessage = "Filters projects that have paths which match the provided string.")]
-  [string]$Exclude = "*template*",
-
-  [Parameter(HelpMessage = "The directories to scan for projects. Supports wildcards.")]
-  [string[]]$projectDirectories = @("$PSScriptRoot/../../*/*/samples/*.Samples/*.Samples.csproj", "$PSScriptRoot/../../*/*/src/*.csproj")
+  [Parameter(HelpMessage = "The directory where props files for discovered projects should be saved.")]
+  [string]$projectPropsOutputDir = "$PSScriptRoot/Generated"
 )
 
-# Create output folder if not exists
+$preWorkingDir = $pwd;
+Set-Location $PSScriptRoot;
+
+# Delete and recreate output folder.
+Remove-Item -Path $projectPropsOutputDir -Recurse -Force -ErrorAction SilentlyContinue | Out-Null;
 New-Item -ItemType Directory -Force -Path $projectPropsOutputDir -ErrorAction SilentlyContinue | Out-Null;
 
 # Discover projects in provided paths
-foreach ($path in $projectDirectories) {
-  foreach ($projectPath in Get-ChildItem -Recurse -Path $path -Exclude $Exclude) {
-    $relativePath = Resolve-Path -Relative -Path $projectPath;
-    $relativePath = $relativePath.TrimStart('.\');
-    $projectName = [System.IO.Path]::GetFileNameWithoutExtension($relativePath);
-    
-    & $PSScriptRoot\GenerateMultiTargetAwareProjectReferenceProps.ps1 $projectPath "$projectPropsOutputDir/$projectName.props";
+foreach ($projectPath in Get-ChildItem -Directory -Depth 0 -Path "$PSScriptRoot/../../labs/") {
+  # Normalize project path
+  $projectName = $projectPath.Name;
+
+  # Folder layout is expected to match the Community Toolkit.
+  # Uses the <MultiTarget> values from the source library project as the fallback for the sample project.
+  # This behavior also implemented in MultiTarget.props for TargetFramework evaluation. 
+  $srcPath = Resolve-Path "$projectPath\src";
+  $srcProjectPath = Get-ChildItem -File "$srcPath\*.csproj";
+
+  $samplePath = Resolve-Path "$projectPath\samples\$projectName.Samples";
+  $sampleProjectPath = Get-ChildItem -File "$samplePath\*.csproj";
+
+  if ($srcProjectPath.Length -eq 0) {
+    Write-Error "Could not locate source csproj for $projectName";
+    exit(-1);
   }
+
+  if ($sampleProjectPath.Length -eq 0) {
+    Write-Error "Could not locate sample csproj for $projectName";
+    exit(-1);
+  }
+
+  # Generate <ProjectReference>s for sample project
+  # Use source project MultiTarget as first fallback.
+  & $PSScriptRoot\GenerateMultiTargetAwareProjectReferenceProps.ps1 -projectPath $sampleProjectPath -outputPath "$projectPropsOutputDir/$($sampleProjectPath.BaseName).props" -multiTargetFallbackPropsPath @("$srcPath/MultiTarget.props", "$samplePath/MultiTarget.props", "$PSScriptRoot/Defaults.props");
+
+  # Generate <ProjectReference>s for src project
+  & $PSScriptRoot\GenerateMultiTargetAwareProjectReferenceProps.ps1 -projectPath $srcProjectPath -outputPath "$projectPropsOutputDir/$($srcProjectPath.BaseName).props" -multiTargetFallbackPropsPath @("$srcPath/MultiTarget.props", "$PSScriptRoot/Defaults.props");
 }
 
+
+Set-Location $preWorkingDir;

MultiTarget/GenerateMultiTargetAwareProjectReferenceProps.ps1

@@ -9,7 +9,7 @@ Param (
     [string]$templatePath = "$PSScriptRoot/MultiTargetAwareProjectReference.props.template",
 
     [Parameter(HelpMessage = "The path to the props file that contains the default MultiTarget values.")] 
-    [string]$multiTargetDefaultPropsPath = "$PSScriptRoot/Defaults.props",
+    [string[]]$multiTargetFallbackPropsPath = @("$PSScriptRoot/Defaults.props"),
 
     [Parameter(HelpMessage = "The placeholder text to replace when inserting the project file name into the template.")] 
     [string]$projectFileNamePlaceholder = "[ProjectFileName]",
@@ -39,8 +39,13 @@ function LoadMultiTargetsFrom([string] $path) {
 
     # If file does not exist
     if ($false -eq (Test-Path -Path $path -PathType Leaf)) {
-        # Load defaults
-        $fileContents = Get-Content $multiTargetDefaultPropsPath -ErrorAction Stop;
+        # Load first available default
+        foreach ($fallbackPath in $multiTargetFallbackPropsPath) {
+            if (Test-Path $fallbackPath) {
+                $fileContents = Get-Content $fallbackPath -ErrorAction Stop;
+                break;
+            }
+        }
     }
     else {
         # Load requested file

MultiTarget/MultiTarget.props

@@ -1,6 +1,14 @@
 <Project>
-  <Import Project="$(MSBuildThisFileDirectory)\Defaults.props" Condition="'$(MultiTarget)' == ''"/>
-  <Import Project="$(MSBuildProjectDirectory)\MultiTarget.props" Condition="Exists('$(MSBuildProjectDirectory)\MultiTarget.props') AND '$(MultiTarget)' == ''"/>
+  <PropertyGroup>
+    <MultiTargetIsSampleProject Condition="$(MSBuildProjectName.EndsWith('.Samples')) == 'true'">true</MultiTargetIsSampleProject>
+  </PropertyGroup>
+
+  <Import Project="$(MSBuildThisFileDirectory)\Defaults.props" Condition="'$(MultiTarget)' == ''" />
+  <Import Project="$(MSBuildProjectDirectory)\MultiTarget.props" Condition="Exists('$(MSBuildProjectDirectory)\MultiTarget.props') AND '$(MultiTarget)' == ''" />
+
+  <!-- If in a sample project, pull the MultiTarget settings from the source project. -->
+  <!-- This behavior is also implemented in GeneratedAllProjectReferences.ps1 for <ProjectReference> generation. -->
+  <Import Project="../../src/MultiTarget.props" Condition="$(MultiTargetIsSampleProject) == 'true' AND !Exists('$(MSBuildProjectDirectory)\MultiTarget.props') AND Exists('../../src/MultiTarget.props')" />
 
   <PropertyGroup>
     <!--
@@ -70,4 +78,4 @@
       <HintPath Condition="Exists('c:\Program Files\Microsoft Visual Studio\2022\Preview\Common7\IDE\Extensions\Xamarin.VisualStudio')">c:\Program Files\Microsoft Visual Studio\2022\Preview\Common7\IDE\Extensions\Xamarin.VisualStudio\Xamarin.Mac.dll</HintPath>
     </Reference>
   </ItemGroup>
-</Project>
+</Project>

MultiTarget/ReadMe.md

@@ -1,12 +1,12 @@
 # MultiTarget
 
-`<MultiTarget>` is a custom property that indicates which target a project is designed to be built for / run on.
+`<MultiTarget>` is a custom property that indicates which target a component is designed to be built for / run on.
 
 The supplied targets are used to create project references, generate solution files, enable/disable TargetFrameworks, and build nuget packages.
 
 ## Basic usage
 
-Create a `MultiTarget.props` file in the same folder as your `.csproj` to change its MultiTarget.
+Create a `MultiTarget.props` file in the root of your source project to change the platform targets for your component. This will be picked up automatically by your sample project, unless it has a `MultiTarget.props` of its own defined.
 
 By default, all available targets are enabled:
 ```xml
@@ -17,7 +17,7 @@ By default, all available targets are enabled:
 </Project>
 ```
 
-A project with this `MultiTarget.props` would only target UWP, WASM and Android:
+For example, to only target UWP, WASM and Android:
 
 ```xml
 <Project>
@@ -27,9 +27,10 @@ A project with this `MultiTarget.props` would only target UWP, WASM and Android:
 </Project>
 ```
 
+
 ## ProjectReference Generation
 
-The script `GenerateAllProjectReferences.ps1` will recursively scan the provided folders for `.csproj` files and generate a `.props` file with a MultiTarget-aware `<ProjectReference>` for each one. 
+The script `GenerateAllProjectReferences.ps1` will scan for experiments and generate `.props` files for each project.
 
 ## NuGet Packages