add clear command

src/Console.js

@@ -1,5 +1,6 @@
 import React from 'react';
-import { XTerm } from 'xterm-for-react'
+import { XTerm } from 'xterm-for-react';
+import { Terminal } from 'xterm';
 
 export class Console extends React.Component {
     constructor(props) {
@@ -16,14 +17,21 @@ export class Console extends React.Component {
                                 background: '#212121',
                                 brightGreen: '#15a179'
                             },
-                            convertEol: true
+                            convertEol: true,
+                            rows: 30,
+                            cols: 200
                         }}
                     />
                 </div>;
     }
 
     componentDidMount() {
-        require('./emulator')(this.terminal.current);
+        const term_ref = this.terminal.current;
-        this.terminal.current.terminal.focus(); 
+        require('./emulator')(term_ref);
+
+        /** @type { Terminal } */
+        const terminal = term_ref.terminal;
+
+        terminal.focus();
     }
 }

src/emulator/commands/clear.js

@@ -0,0 +1,25 @@
+const { Terminal } = require("xterm");
+const package = require('../../../package.json');
+
+/**
+ * 
+ * @param {string[]} argv 
+ * @param {Terminal} terminal 
+ */
+module.exports = (argv, terminal) => {
+    if (argv.indexOf('--help') != -1) {
+        terminal.write(
+`Usage: ${argv[0]} [options]
+    -V Print resume.js version
+`
+        );
+        return;
+    }
+
+    if (argv.indexOf('-V') != -1) {
+        terminal.write(`resume.js version ${package.version} by ${package.author}\n`);
+        return;
+    }
+
+    terminal.clear();
+}

src/emulator/commands/index.js

@@ -11,6 +11,7 @@ let cmds = {
     'import_file': require('./import_file'),
     'zsh': require('./zsh'),
     'ps': require('./ps'),
+    'clear': require('./clear'),
 
     // alias l='ls -l'
     'l': (a,t) => {require('./ls')([...a, '-l'], t)},