qt-python: Introduce a new command for PySide6 installation

This commit adds the `qt-python.installPySide6` command.
It first checks the installation status of PySide6 and then shows a
picker for the user to select which version they would like to install.

The first item allows installation from PyPI.
Picker can also include local installation sources under
`<Qt installation root>/QtForPython`.
This UI construction is similar to that of Qt Creator.

If no virtual environment is selected, a popup will appear guiding
the user to create or select a virtual environment first.

Author: benchoq

qt-python/package.json

@@ -40,6 +40,21 @@
       "title": "Qt Python Configuration",
       "properties": {}
     },
+    "commands": [
+      {
+        "command": "qt-python.installPySide6",
+        "title": "%qt-python.command.installPySide6.title%",
+        "category": "Qt"
+      }
+    ],
+    "menus": {
+      "commandPalette": [
+        {
+          "command": "qt-python.installPySide6",
+          "when": "workspaceFolderCount > 0"
+        }
+      ]
+    },
     "taskDefinitions": [
       {
         "type": "pyside",

qt-python/package.nls.json

@@ -1 +1,3 @@
-{}
+{
+  "qt-python.command.installPySide6.title": "Python: Install PySide6"
+}

qt-python/src/builder.ts

@@ -0,0 +1,82 @@
+// Copyright (C) 2025 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only
+
+import * as path from 'path';
+import * as childProcess from 'child_process';
+
+import { IsWindows } from 'qt-lib';
+import { PySideEnv } from './env';
+
+export interface PySideCommandBuildOptions {
+  useVenv?: boolean;
+  cwd?: string;
+}
+
+export class PySideCommandBuilder {
+  private readonly _shellPath: string;
+  private readonly _shellArgs: string[];
+  private readonly _venvActivationCommand: string;
+
+  constructor(
+    private readonly _env: PySideEnv,
+    private readonly _options?: PySideCommandBuildOptions
+  ) {
+    this._shellPath = resolveShellPath();
+    this._shellArgs = [IsWindows ? '/c' : '-c'];
+    this._venvActivationCommand = resolveVenvActivationCommand(this._env);
+  }
+
+  get shellPath(): string {
+    return this._shellPath;
+  }
+
+  get shellArgs(): string[] {
+    return this._shellArgs;
+  }
+
+  get venvActivationCommand(): string {
+    return this._venvActivationCommand;
+  }
+
+  public build(command: string) {
+    const all: string[] = [command];
+
+    if (this._options?.cwd) {
+      all.unshift(`cd ${enclosePath(this._options.cwd)}`);
+    }
+
+    if (this._options?.useVenv && this._venvActivationCommand) {
+      all.unshift(this._venvActivationCommand);
+    }
+
+    return all.join(' && ');
+  }
+}
+
+// helpers
+function resolveShellPath(): string {
+  if (IsWindows) {
+    return process.env.ComSpec ?? 'C:\\Windows\\System32\\cmd.exe';
+  }
+
+  const result = childProcess.spawnSync('command -v bash', { shell: true });
+  const found = result.stdout.toString().trim();
+  return result.status === 0 && found ? found : '/bin/bash';
+}
+
+function resolveVenvActivationCommand(env: PySideEnv): string {
+  const bin = env.venvBinPath;
+  if (!bin) {
+    return '';
+  }
+
+  const script = enclosePath(
+    path.join(bin, IsWindows ? 'activate.bat' : 'activate')
+  );
+
+  return IsWindows ? script : `source ${script}`;
+}
+
+function enclosePath(s: string) {
+  return IsWindows ? `"${s}"` : `'${s}'`;
+}

qt-python/src/constants.ts

@@ -7,6 +7,11 @@ export const EXTENSION_ID = 'qt-python';
 export const MS_PYTHON_ID = 'ms-python.python';
 export const LOG_NAME = 'qt-python';
 
+export const COMMAND_PREFIX = 'qt-python';
+export const COMMAND_INSTALL_PYSIDE = 'installPySide6'; // contributes > commands
+export const COMMAND_PYTHON_CREATE_ENV = 'python.createEnvironment';
+export const COMMAND_PYTHON_SELECT_PYTHON = 'python.setInterpreter';
+
 export const TASK_TYPE = 'pyside'; // contributes > taskDefinitions
 export const TASK_SOURCE = 'PySide';
 
@@ -21,3 +26,4 @@ export const TOML_KEY_PROJECT_NAME = 'project.name';
 export const TOML_KEY_PROJECT_FILES = 'tool.pyside6-project.files';
 
 export const PYSIDE_PROJECT_TOOL = 'pyside6-project';
+export const MAINT_WHEEL_DIR_NAME = 'QtForPython';

qt-python/src/env.ts

@@ -14,10 +14,22 @@ export class PySideEnv {
     this._pyEnv = pyenv;
   }
 
+  public isVenv(): boolean {
+    return this._pyEnv?.environment?.type === 'VirtualEnvironment';
+  }
+
+  get venvName(): string | undefined {
+    return this._pyEnv?.environment?.name;
+  }
+
   get venvBinPath(): string {
     const root = this._pyEnv?.executable.sysPrefix ?? '';
     return root
       ? utils.toForwardSlash(path.join(root, consts.VENV_BIN_DIR))
       : '';
   }
+
+  get interpreterPath(): string | undefined {
+    return this._pyEnv?.executable.uri?.fsPath;
+  }
 }

qt-python/src/extension.ts

@@ -18,6 +18,7 @@ import { PySideTaskProvider } from './task';
 import { PySideDebugConfigProvider } from './debug';
 import { PySideProjectManager } from './project-manager';
 import * as consts from '@/constants';
+import { onInstallPySide6Command } from './installer';
 
 const logger = createLogger('extension');
 
@@ -34,6 +35,8 @@ export async function activate(context: vscode.ExtensionContext) {
     await initDependency();
     await initCoreApi();
     await initPythonSupport(context);
+    initCommands(context);
+
     logger.info(`Activated: ${consts.EXTENSION_ID}`);
     telemetry.sendEvent('activated');
   } catch (e) {
@@ -74,6 +77,22 @@ async function initPythonSupport(context: vscode.ExtensionContext) {
   );
 }
 
+function initCommands(context: vscode.ExtensionContext) {
+  function register(c: string, callback: (...args: unknown[]) => unknown) {
+    return vscode.commands.registerCommand(
+      `${consts.COMMAND_PREFIX}.${c}`,
+      async () => {
+        telemetry.sendAction(c);
+        await callback();
+      }
+    );
+  }
+
+  context.subscriptions.push(
+    register(consts.COMMAND_INSTALL_PYSIDE, onInstallPySide6Command)
+  );
+}
+
 const onPyApiEnvChanged = async (e: PyApiEnvChanged) => {
   const folder = e.resource;
   if (folder) {