fix: mock replaceChildren (#21)

Author: eirikb

lib/widgets/terminal.ts

@@ -53,6 +53,7 @@ interface MockElement {
   getAttribute(): void;
   focus(): void;
   blur(): void;
+  replaceChildren(): void;
 }
 
 interface TermObject {
@@ -250,6 +251,12 @@ Terminal.prototype.bootstrap = function (this: TerminalInterface): void {
     style: {},
     focus: function () {},
     blur: function () {},
+    replaceChildren: function () {
+      // Mock implementation of Element.replaceChildren()
+      // Accepts any number of Node objects or strings as arguments
+      // In real DOM, this would replace all children with provided nodes
+      // For mock, we can just do nothing (no-op)
+    },
     console: console,
     // Mock DOM APIs that xterm.js needs
     classList: {

test/widget-terminal-replacechildren-crash.ts

@@ -0,0 +1,64 @@
+/**
+ * Test to reproduce the replaceChildren crash in terminal widget
+ * This test demonstrates that xterm.js's DomRenderer can now call
+ * replaceChildren on the mock DOM element without crashing
+ */
+
+var blessed = require('../');
+var path = require('path');
+
+console.log('🧪 Testing terminal widget replaceChildren crash fix...');
+
+var screen = blessed.screen({
+  dump: path.join(__dirname, '/logs/terminal-replacechildren.log'),
+  warnings: true,
+  fullUnicode: true,
+});
+
+// Create a terminal similar to the usage in anton app
+var terminal = blessed.terminal({
+  parent: screen,
+  top: 0,
+  left: 0,
+  width: 40,
+  height: 20,
+  border: 'line',
+  label: ' Test Terminal ',
+  shell: '/bin/bash',
+  args: ['-c', 'sleep 1000000'],
+  fullUnicode: true,
+});
+
+// Write some data to trigger rendering
+terminal.write('Test output\r\n');
+terminal.write('This should trigger xterm rendering\r\n');
+
+screen.render();
+
+// Give it a moment to initialize and render
+setTimeout(function () {
+  try {
+    // Trigger the problematic cleanup path
+    // This simulates what happens when stream.on("end") is called
+    terminal.destroy();
+    screen.destroy();
+
+    // If we get here without error, the bug is fixed
+    console.log(
+      '✅ SUCCESS: Terminal can be destroyed without replaceChildren crash!'
+    );
+    process.exit(0);
+  } catch (err) {
+    if (
+      err.message &&
+      err.message.includes('replaceChildren is not a function')
+    ) {
+      console.error('❌ FAIL: replaceChildren is still missing:', err.message);
+      process.exit(1);
+    } else {
+      console.error('❌ UNEXPECTED ERROR:', err.message);
+      console.error(err.stack);
+      process.exit(2);
+    }
+  }
+}, 500);