Plugin UnitTest Harness

This plugin provides deferred testcases, such you are able to run sublime commands from your test cases and give control to sublime text and get it back later.


Create a folder for your tests. If you want to stay sublime text 2 compatible you should not call it "tests" in your main plugin folder, because of name clashes.

Following layout is recommended:

  • My Fancy Plugin - my_fancy_plugin

    • tests - - -
    • My Fancy
    • My Fancy Plugin.sublime-commands
My Fancy
... is your major plugin file, which is automatically reloaded by Sublime Text on change. The other python files within subfolders are not. This contains your commands you export to sublime text or whatever.
My Fancy Plugin.sublime-commands
This has to contain a command to start your tests::
{ "caption": "My Fancy Plugin: Run Tests",
"command": "run_plugin_unittest", "args": {"module": "My Fancy Plugin.my_fancy_plugin.tests"} }



On each test the module passed to run_plugin_unittest is reloaded. So this file is responsible to reload everything, which is needed for the test:

# this is the class, which is run by run_plugin_unittest

from imp import reload

# make sure we have got latest changes

from . import test_first_collection

from . import test_second_collection

from .. import some_file

# import all testcases
from .test_first_collection import *
from .test_second_collection import *

This contains testcases:

from sublime_unittest import TestCase
import sublime

class MyTest(TestCase):

    def test_first(self):
        view = sublime.active_window().open_file("some file")

        while view.is_loading():
            yield     # default is to continue in 10ms

        self.assertEquals(, "some file")

    def test_second(self):
        view = sublime.active_window().open_file("some file")

        while view.is_loading():
            yield 2   # I specify that sublime shall continue this code in 2ms

        self.assertEquals(view.file_name(), "some file")

and so on ...

Simple Buffer Tests

You can create simple buffer tests like this:

from sublime_unittest import *

class MyBufferTest(BufferTest):
    test_cursor = (
        "initial │content of buffer",
        v('move', {'by': 'characters', 'forward': False}),
        "initial│ content of buffer",

    # here buffer is selected
    test_selection = (
        "initial content of ┤buffer├",
        v('insert', {'characters': "view"}),
        "initial content of view│",

    # multiple cursors
    test_multiple_cursors = (
        "initial ┤content├ of bu│ffer",
        v('move', {'by': 'characters', 'forward': True}),
        "initial content │of buf│fer",
        v('insert', {'characters': 'f'}),
        "initial content f│of buff│fer",

    # line assertions
    test_line_assertion = (
        first ┤line
        second├ l│ine
        (2, "second├ l│ine")
  • all test names have to start with 'test'

  • You specify a text command (or view command) with v and a window command with w.

  • Each string means an assertion.

  • You can mix commands and assertions however you like.

  • and encloses a selection and is an empty selection, i.e. a cursor.


    Using Character Table Plugin you can shortcut these characters with ctrl+k,v,l, ctrl+k,v,r and ctrl+k,v,v


  • have some TestCase.sendkeys() method to send keys after opening a panel


  • added BufferTest for convenient buffer tests
  • added opportunity to yield a method to wait for some condition before continuing test


Kay-Uwe (Kiwi) Lorenz <> (

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