new file mode 100644
--- /dev/null
+++ b/.zfun/zsh-autosuggestions/spec/terminal_session.rb
@@ -0,0 +1,99 @@
+require 'securerandom'
+
+class TerminalSession
+  ZSH_BIN = ENV['TEST_ZSH_BIN'] || 'zsh'
+
+  def initialize(opts = {})
+    opts = {
+      width: 80,
+      height: 24,
+      prompt: '',
+      term: 'xterm-256color',
+      zsh_bin: ZSH_BIN
+    }.merge(opts)
+
+    @opts = opts
+
+    cmd="PS1=\"#{opts[:prompt]}\" TERM=#{opts[:term]} #{ZSH_BIN} -f"
+    tmux_command("new-session -d -x #{opts[:width]} -y #{opts[:height]} '#{cmd}'")
+  end
+
+  def zsh_version
+    @zsh_version ||= Gem::Version.new(`#{ZSH_BIN} -c 'echo -n $ZSH_VERSION'`)
+  end
+
+  def tmux_socket_name
+    @tmux_socket_name ||= SecureRandom.hex(6)
+  end
+
+  def run_command(command)
+    send_string(command)
+    send_keys('enter')
+
+    self
+  end
+
+  def send_string(str)
+    tmux_command("send-keys -t 0 -l -- '#{str.gsub("'", "\\'")}'")
+
+    self
+  end
+
+  def send_keys(*keys)
+    tmux_command("send-keys -t 0 #{keys.join(' ')}")
+
+    self
+  end
+
+  def paste_string(str)
+    tmux_command("set-buffer -- '#{str}'")
+    tmux_command("paste-buffer -dpr -t 0")
+
+    self
+  end
+
+  def content(esc_seqs: false)
+    cmd = 'capture-pane -p -t 0'
+    cmd += ' -e' if esc_seqs
+    tmux_command(cmd).strip
+  end
+
+  def clear_screen
+    send_keys('C-l')
+
+    i = 0
+    until content == opts[:prompt] || i > 20 do
+      sleep(0.1)
+      i = i + 1
+    end
+
+    self
+  end
+
+  def destroy
+    tmux_command('kill-session')
+  end
+
+  def cursor
+    tmux_command("display-message -t 0 -p '\#{cursor_x},\#{cursor_y}'").
+      strip.
+      split(',').
+      map(&:to_i)
+  end
+
+  def attach!
+    tmux_command('attach-session')
+  end
+
+  private
+
+  attr_reader :opts
+
+  def tmux_command(cmd)
+    out = `tmux -u -L #{tmux_socket_name} #{cmd}`
+
+    raise("tmux error running: '#{cmd}'") unless $?.success?
+
+    out
+  end
+end