Fix UsePythonVersion@0 installing incomplete Python files on Windows

Tasks/UsePythonVersionV0/Tests/L0ValidatesIncompleteInstallation.ts

@@ -0,0 +1,139 @@
+import * as path from 'path';
+import * as fs from 'fs';
+
+import { TaskMockRunner } from 'azure-pipelines-task-lib/mock-run';
+
+const taskPath = path.join(__dirname, '..', 'main.js');
+const taskRunner = new TaskMockRunner(taskPath);
+
+const TEST_GITHUB_TOKEN = 'testtoken';
+
+taskRunner.setInput('versionSpec', '3.12.x');
+taskRunner.setInput('disableDownloadFromRegistry', 'false');
+taskRunner.setInput('addToPath', 'true');
+taskRunner.setInput('architecture', 'x64');
+taskRunner.setInput('githubToken', TEST_GITHUB_TOKEN);
+
+// `getVariable` is not supported by `TaskLibAnswers`
+process.env['AGENT_TOOLSDIRECTORY'] = '$(Agent.ToolsDirectory)';
+process.env['APPDATA'] = 'testappdata';
+
+let pythonWasInstalled = false;
+let setupExecuted = false;
+
+// Mock azure-pipelines-tool-lib
+taskRunner.registerMock('azure-pipelines-tool-lib/tool', {
+    findLocalTool() {
+        if (!pythonWasInstalled) {
+            return null;
+        }
+
+        return path.join('C', 'tools', 'Python', '3.12.10', 'x64');
+    },
+    findLocalToolVersions: () => pythonWasInstalled ? ['3.12.10'] : [],
+    downloadTool: () => Promise.resolve('C:/downloaded/python.zip'),
+    extractZip: () => Promise.resolve('C:/extracted/python'),
+    extractTar() {
+        throw new Error('This should never be called');
+    },
+});
+
+taskRunner.registerMock('os', {
+    platform() {
+        return 'win32';
+    },
+    arch() {
+        return 'x64';
+    },
+    EOL: '\r\n'
+});
+
+// Can't mock process, so have to mock taskutil instead
+enum Platform {
+    Windows,
+    MacOS,
+    Linux
+}
+
+taskRunner.registerMock('./taskutil', {
+    Platform,
+    getPlatform() {
+        return Platform.Windows;
+    }
+});
+
+const tl = require('azure-pipelines-task-lib/mock-task');
+const tlClone = Object.assign({}, tl);
+tlClone.exec = function(command, args, options) {
+    if (command !== 'powershell' || args !== './setup.ps1') {
+        throw new Error(`Invalid command and arguments: ${command} ${args}`);
+    }
+
+    if (options.cwd !== 'C:/extracted/python') {
+        throw new Error(`Invalid python installer dir path: ${options.cwd}`);
+    }
+
+    setupExecuted = true;
+    pythonWasInstalled = true;
+};
+
+// Mock fs.promises to simulate incomplete installation
+const fsMock = {
+    ...fs,
+    promises: {
+        stat: async (filePath: string) => {
+            // Simulate python.exe exists
+            if (filePath.endsWith('python.exe')) {
+                return { isFile: () => true, isDirectory: () => false };
+            }
+            // Simulate missing Lib directory (incomplete installation)
+            if (filePath.endsWith('Lib')) {
+                throw new Error('ENOENT: no such file or directory');
+            }
+            // Simulate missing libs directory (incomplete installation)
+            if (filePath.endsWith('libs')) {
+                throw new Error('ENOENT: no such file or directory');
+            }
+            // Simulate missing include directory (incomplete installation)
+            if (filePath.endsWith('include')) {
+                throw new Error('ENOENT: no such file or directory');
+            }
+            // Default to file not existing
+            throw new Error('ENOENT: no such file or directory');
+        },
+        readdir: async (dirPath: string) => {
+            // This shouldn't be called in our incomplete installation scenario
+            return [];
+        }
+    }
+};
+
+taskRunner.registerMock('fs', fsMock);
+taskRunner.registerMock('azure-pipelines-task-lib/mock-task', tlClone);
+
+// Test manifest contains stable python 3.12.10, so the task should find it
+taskRunner.registerMock('typed-rest-client', {
+    RestClient: class {
+        get(_url: string) {
+            return Promise.resolve({
+                result: [
+                    {
+                        "version": "3.12.10",
+                        "stable": true,
+                        "release_url": "https://github.com/actions/python-versions/releases/tag/3.12.10-14343898437",
+                        "files": [
+                            {
+                                "filename": "python-3.12.10-win32-x64.zip",
+                                "arch": "x64",
+                                "platform": "win32",
+                                "download_url": "https://github.com/actions/python-versions/releases/download/3.12.10-14343898437/python-3.12.10-win32-x64.zip"
+                            }
+                        ]
+                    }
+                ]
+            });
+        }
+    }
+});
+
+taskRunner.run();