Avoid needing to initialize tty state in bootstrap scripts

kitty_tests/__init__.py

@@ -194,6 +194,15 @@ class PTY:
         self.screen = Screen(self.callbacks, rows, columns, scrollback, cell_width, cell_height, 0, self.callbacks)
         self.received_bytes = b''
 
+    def turn_off_echo(self):
+        s = termios.tcgetattr(self.master_fd)
+        s[3] &= ~termios.ECHO
+        termios.tcsetattr(self.master_fd, termios.TCSANOW, s)
+
+    def is_echo_on(self):
+        s = termios.tcgetattr(self.master_fd)
+        return True if s[3] & termios.ECHO else False
+
     def __del__(self):
         if not self.is_child:
             fd = self.master_fd

kitty_tests/ssh.py

@@ -156,6 +156,7 @@ copy --exclude */w.* d1
                 pty.wait_till(lambda: 'TSET={}'.format(tset.replace('$A', 'AAA')) in pty.screen_contents())
                 self.assertNotIn('COLORTERM', pty.screen_contents())
                 pty.wait_till(lambda: '/cwd' in pty.screen_contents())
+                self.assertTrue(pty.is_echo_on())
 
     def test_ssh_bootstrap_with_different_launchers(self):
         for launcher in self.all_possible_sh:
@@ -252,6 +253,7 @@ copy --exclude */w.* d1
             open(os.path.join(home_dir, '.zshrc'), 'w').close()
             cmd = wrap_bootstrap_script(script, sh)
             pty = self.create_pty([launcher, '-c', ' '.join(cmd)], cwd=home_dir, env=env)
+            pty.turn_off_echo()
             del cmd
             if pre_data:
                 pty.write_buf = pre_data.encode('utf-8')