Add an optional architecture parameter to set the target architecture (x86, x64, arm64, ...).

README.md

@@ -28,6 +28,17 @@ steps:
 - run: dotnet build <my project>
 ```
 
+**Specific architecture:**
+```yml
+steps:
+- uses: actions/checkout@v3
+- uses: actions/setup-dotnet@v2
+  with:
+    dotnet-version: '6.0.x'
+    architecture: 'x86'
+- run: dotnet build <my project>
+```
+
 **Multiple version installation**:
 ```yml
 steps:

__tests__/installer.test.ts

@@ -107,6 +107,24 @@ describe('DotnetCoreInstaller tests', () => {
     expect(process.env.PATH?.startsWith(toolDir)).toBe(true);
   }, 600000); //This needs some time to download on "slower" internet connections
 
+  it('Acquires architecture-specific version of dotnet if no matching version is installed', async () => {
+    await getDotnet('3.1', '', 'x64');
+    var directory = fs
+      .readdirSync(path.join(toolDir, 'sdk'))
+      .filter(fn => fn.startsWith('3.1.'));
+    expect(directory.length > 0).toBe(true);
+    if (IS_WINDOWS) {
+      expect(fs.existsSync(path.join(toolDir, 'dotnet.exe'))).toBe(true);
+    } else {
+      expect(fs.existsSync(path.join(toolDir, 'dotnet'))).toBe(true);
+    }
+
+    expect(process.env.DOTNET_ROOT).toBeDefined;
+    expect(process.env.PATH).toBeDefined;
+    expect(process.env.DOTNET_ROOT).toBe(toolDir);
+    expect(process.env.PATH?.startsWith(toolDir)).toBe(true);
+  }, 600000); //This needs some time to download on "slower" internet connections
+
   it('Returns string with installed SDK version', async () => {
     const version = '3.1.120';
     let installedVersion: string;
@@ -279,10 +297,12 @@ function normalizeFileContents(contents: string): string {
 async function getDotnet(
   version: string,
   quality: string = ''
+  architecture: string = ''
 ): Promise<string> {
   const dotnetInstaller = new installer.DotnetCoreInstaller(
     version,
-    quality as QualityOptions
+    quality as QualityOptions,
+    architecture
   );
   const installedVersion = await dotnetInstaller.installDotnet();
   installer.DotnetCoreInstaller.addToPath();

action.yml

@@ -17,6 +17,9 @@ inputs:
     description: 'Optional OWNER for using packages from GitHub Package Registry organizations/users other than the current repository''s owner. Only used if a GPR URL is also provided in source-url'
   config-file:
     description: 'Optional NuGet.config location, if your NuGet.config isn''t located in the root of the repo.'
+  architecture:
+    description: 'Optional architecture to use. If not provided, will default to the OS architecture.'
+    required: False
 outputs:
   dotnet-version:
     description: 'Contains the installed by action .NET SDK version for reuse.'

src/installer.ts

@@ -20,9 +20,11 @@ export interface DotnetVersion {
 export class DotnetVersionResolver {
   private inputVersion: string;
   private resolvedArgument: DotnetVersion;
+  private architecture: string;
 
-  constructor(version: string) {
+  constructor(version: string, architecture: string = '') {
     this.inputVersion = version.trim();
+    this.architecture = architecture;
     this.resolvedArgument = {type: '', value: '', qualityFlag: false};
   }
 
@@ -230,6 +232,10 @@ export class DotnetCoreInstaller {
       if (this.quality) {
         this.setQuality(dotnetVersion, scriptArguments);
       }
+      
+      if (this.architecture != '') {
+        scriptArguments.push('--architecture', this.architecture);
+      }
     }
     // process.env must be explicitly passed in for DOTNET_INSTALL_DIR to be used
     const getExecOutputOptions = {

src/setup-dotnet.ts

@@ -28,6 +28,11 @@ export async function run() {
     //
     const versions = core.getMultilineInput('dotnet-version');
     const installedDotnetVersions: string[] = [];
+    let architecture = core.getInput('architecture');
+    
+    if (!architecture) {
+      architecture = '';
+    }
 
     const globalJsonFileInput = core.getInput('global-json-file');
     if (globalJsonFileInput) {
@@ -61,7 +66,7 @@ export async function run() {
       let dotnetInstaller: DotnetCoreInstaller;
       const uniqueVersions = new Set<string>(versions);
       for (const version of uniqueVersions) {
-        dotnetInstaller = new DotnetCoreInstaller(version, quality);
+        dotnetInstaller = new DotnetCoreInstaller(version, quality, architecture);
         const installedVersion = await dotnetInstaller.installDotnet();
         installedDotnetVersions.push(installedVersion);
       }