vscode-paste-indented.ts

import * as vscode from 'vscode';
import redent from 'redent';

export function activate(context: vscode.ExtensionContext) {
  vscode.commands.registerCommand('selfhost.pasteWithIndent', async () => {
    const text = await vscode.env.clipboard.readText()
    if (!text) return;

    const editor = vscode.window.activeTextEditor
    if (editor) {
      // Get cursor indentation by calculating the whitespace before the cursor
      let cursorLine = editor.document.lineAt(editor.selection.active.line);
      let cursorIndent = cursorLine.text.substring(0, editor.selection.active.character).match(/^\s*/)?.[0] || '';

      // Redent the clipboard text to match the cursor indentation
      const redentedText = redent(text, cursorIndent.length).trimStart();
      editor.edit(b => b.insert(editor.selection.active, redentedText))
    }
  })
}

/** package.json

  "contributes": {
    "commands": [
      {
        "command": "selfhost.pasteWithIndent",
        "title": "Selfhost: Paste With Indent"
      }
    ],
    "keybindings": [
      {
        "command": "selfhost.pasteWithIndent",
        "key": "cmd+shift+v",
        "when": "editorTextFocus"
      }
    ]
  },

*/