Automated Testing

Ren'Py allows creators to put automated tests in their games to make sure that alterations to the game don't break existing functionality. This is especially useful for large games, or for games that are frequently updated.

The two main components of the testing system are the testcase and testsuite statements.

The renpy.is_in_test() function is helpful to know whether a test is currently executing or not.

Testcase Statement

The testcase statement creates a named test case. Each case contains a block of test statements (see below). Test cases are similar to Ren'Py labels, with a few differences:

• The Ren'Py label statement takes Ren'Py code, while the testcase statement takes test statements (listed on this page). They are mutually exclusive.

• There is no testcase equivalent of the return statement.

• There can be no test statement outside of a test block, while there can be Ren'Py code outside labels (in init blocks for example).

It takes the following properties:

enabled

If this expression evaluates to False, this test is skipped. Defaults to True.

This can conditionally disable tests, for example on platforms where they are not supported.

testcase windows:
    enabled renpy.windows
    ...

testcase not_on_mobile:
    enabled not renpy.mobile
    ...

See Skipping Testcases for more information.

only

If this expression evaluates to True, only this test case (and other tests with only True) will be run. Defaults to False.

See Skipping Testcases for more information.

description

A string describing the test case. This is used in the test report.

Testsuite Statement

The testsuite statement is used to group test cases together. Test suites can contain test cases, other test suites, and hooks (see below).

The default test suite is named global, and it is automatically created by Ren'Py if not specified by the user. It contains all other top-level test suites and test cases in the game.

It takes the same properties as the testcase statement.

Hooks

The testsuite statement can contain the following hooks:

setup

A block of test statements that is executed once, before running any tests contained within the current suite.

before testsuite

A block of test statements that is executed repeatedly, running before each test suite within the current suite.

before testcase

A block of test statements that is executed repeatedly, running before each test case within the current suite.

after testcase

A block of test statements that is executed repeatedly, running after each test case in the current suite. The is run even if the testcase fails or raises an exception.

after testsuite

A block of test statements that is executed repeatedly, running after each test suite in the current suite. The is run even if the testsuite fails or raises an exception.

teardown

A block of test statements that is executed once, after running all tests contained within the current suite. This is run even if a test fails or raises an exception.

The before * and after * hooks take the following properties:

depth

An integer specifying how deep the hook should apply.

For testcases, defaults to -1, meaning it applies to all nested test suites and test cases.

For testsuites, defaults to 0, meaning it applies only to test suites directly contained within the current suite.

For more information, see Lifecycle of a Test Run.

Lifecycle of a Test Run

This section describes the order in which testcases and testsuites are executed, and how the hooks are called. The following example illustrates this:

Note that global :: before testcase and global :: after testcase are executed before and after each test case, even if the test case is inside a nested test suite.

In order to limit the scope of a hook, set its depth property. Setting it to 0 will make the hook execute only for tests directly inside the test suite containing the hook.

For example:

testsuite global:
    before testcase:
        depth 0
        $ print("Starting a testcase.")

On the other hand, the before testsuite and after testsuite hooks have a default depth of 0, meaning they will only execute for testsuites directly inside the testsuite containing the hook.

To increase the scope of a hook to include nested testsuites and testcases, set its depth property to -1 (for infinite depth) or to a positive integer (for a specific depth).

Note

When a testsuite finishes executing, the game doesn't close itself. Instead, it will return control of the game back to the player, awaiting user input.

To close the game after a testsuite, you can use the exit test statement in the after hook of the testsuite. For example:

testsuite global:
    teardown
        exit

Skipping Testcases

If a testcase is skipped, it will not be executed. In addition, the before testcase and after testcase hooks of the testsuite will not be executed for that testcase.

If all tests are skipped in a testsuite, then the setup and teardown hooks will not be executed either. In addition, the before testsuite and after testsuite hooks will not be executed from the parent testsuite(s).

Exceptions And Failures

If an error occurs during a test case:

1. The test case will stop executing immediately

2. The after testcase hook of the testsuite containing the test case will run

3. If there are more test cases, they will continue to be executed (including the before testcase hook)

4. If no more test cases exist, the after hook of the testsuite will run

If an error occurs during a hook (eg. before testcase):

1. The test suite will stop executing immediately

2. If the suite was called by another suite, the parent suite will continue executing.

3. If no parent suite exists, the game will end the test run.

Test Launch Options

The test system accepts the following command-line options:

--ignore_enabled_flag

If provided, all test cases and test suites will be executed, regardless of their enabled property.

--print_details

If provided, the test report will include details about each test case, including its description and the time it took to execute.

--print_skipped

If provided, the test report will include information about skipped test cases and test suites. Requires --print_details to be enabled as well.

Test Reporting

After a test run, a report is printed to the console, listing all test cases that were executed, skipped, failed, or raised an error.

Below is an example of a test report after successfully testing "The Question":

Test Settings

The following variables can be set to change the behavior of tests:

_test.maximum_framerate

A boolean specifying whether to use maximum framerate mode during tests. This will unlock the framerate beyond your screens refresh rate if possible. Defaults to True.

_test.timeout

A float specifying the maximum number of seconds a test statement should wait for a condition to be met. Defaults to 10.0.

This can be overridden on a per-statement basis by providing a timeout property to statements that support it (like assert and until).

_test.force

A boolean specifying whether to force the test to proceed even if renpy.config.suppress_underlay is True. Defaults to False.

_test.transition_timeout

A float specifying the maximum number of seconds to wait for a transition to complete before skipping it and proceeding with the test. Defaults to 5.0.

_test.focus_trials

An integer specifying how many times the test system should try to find a valid spot to move the mouse when using a selector without a position. Defaults to 100.

Test Statements

Test statements are the building blocks of test cases. They can be broadly divided into three categories: command statements, condition/selector statements, and control statements.

Basic Commands

Advance

Type: Command

advance

Advances the game by one dialogue line.

advance
advance until screen "choice"

Exit

Type: Command

exit

Quits the game without calling the confirmation screen. Does not save the game when quitting.

if eval need_to_confirm:
    # Asks for confirmation, and autosaves if config.autosave_on_quit is True
    run Quit(confirm=True)

if eval persistent.quit_test_using_action:
    # Does not ask, but still autosaves if config.autosave_on_quit is True
    run Quit(confirm=False)

exit # neither asks nor autosaves

Pass

Type: Command

pass

Does not do anything. It's a no-op, allowing for empty testcases.

testcase not_yet_implemented:
    pass

Pause

Type: Command

pause [time (float)]

Pauses test execution for a given number of seconds. Similar to the Pause Statement, but requires a value, or it can be specified without a time if it is followed by an until clause.

pause 5.0
pause until screen "inventory"

Run

Type: Command

run <action>

Runs the provided screen-language action (or list of actions).

Ready if and when a button containing the provided action (or list) would be sensitive.

testcase chapter_3:
    run Jump("chapter_3")

Skip

Type: Command

skip [fast]

Causes the game to begin skipping. If the game is in a menu context, then this returns to the game. Otherwise, it just enables skipping.

If fast is provided, the game will skip directly to the next menu choice.

skip
skip fast
skip until screen "choice"

Mouse Commands

Click

Type: Command

click [button (int)] [selector] [pos (x, y)]

Executes a simulated click on the screen. It takes the following optional properties:

• button specifies which button of the simulated mouse is to be clicked

  with. It takes an integer and defaults to 1. 1 is a left-click, 2 is a right-click, 3 is a middle-click, 4 and 5 are additional buttons found on some mouses. Normally only 1 and 2 trigger any response from Ren'Py.

If selector and/or pos are given, the virtual test mouse is moved according to the rules of the move statement before the click is sent.

Click behaves like a pattern-taking clause which would not be given a pattern: if no pos is provided, it will look for a neutral place where a click would not occur on a focusable element.

Note

Use the advance or skip statements if you want to advance the game's dialogue. Clicking may result in unpredictable results, depending on where the mouse is positioned and what is currently on the screen.

Drag

Type: Command

drag <[selector] [pos (x, y)]> to <[selector] [pos (x, y)]> [button (int)] [steps (int)]

Simulates a drag action on the screen. It takes the following properties:

• The first part (before the to) specifies the starting point of the drag. It takes an optional selector and/or pos property, which are interpreted according to the rules of the move statement.

• The second part (after the to) specifies the ending point of the drag. It also takes an optional selector and/or pos property, which are interpreted according to the rules of the move statement.

• button specifies which button of the simulated mouse is to be used for the drag. It takes an integer and defaults to 1. 1 is a left-click, 2 is a right-click, 3 is a middle-click, 4 and 5 are additional buttons found on some mouses. Normally only 1 and 2 trigger any response from Ren'Py.

• steps specifies how many intermediate steps the drag should take. It takes an integer and defaults to 10. More steps result in a smoother drag, but also take more time.

drag id "item_icon" to id "inventory_slot_3" button 1 steps 20
drag pos (100, 200) to pos (400, 500) button 1
drag id "item_icon" pos (0.5, 0.5) to pos (300, 400) steps 5
drag pos (50, 50) to id "inventory_slot_1"
drag pos (50, 50) to pos (150, 150)

Move

Type: Command

move [selector] [pos (x, y)]

Moves the virtual test mouse to a given position on the screen.

If a selector is given, and:

• If pos is specified, the mouse is moved to that position relative to the selector.

• If no pos is specified, the mouse attempts to find a pixel that would focus the selector if clicked. This takes into account things like focus_mask.

If no selector is given, and:

• If pos is specified, the mouse is moved to that position relative to the screen.

• If no pos is specified, an error is thrown.

# Move to a random clickable point within `back_btn`
move id "back_btn"

# Move to the center of `back_btn`
move id "back_btn" pos (0.5, 0.5)

# Move to a point 20 pixels right and 10 pixels down from the top-left corner of `back_btn`
move id "back_btn" pos (20, 10)

# Move to the top right corner of the screen
move pos (1.0, 0.0)

# Move to a point 20 pixels right and 10 pixels down from the top-left corner of the screen
move pos (20, 10)

Scroll

Type: Command

scroll [amount (int)] [selector] [pos (x, y)]

Simulates a scroll event. It takes the following optional properties:

• amount specifies how many "notches" to scroll. It takes an integer and defaults to 1. Positive values scroll down, negative values scroll up.

• If selector and/or pos are given, the virtual test mouse is moved according to the rules of the move statement before the scroll is sent.

scroll "bar"
scroll id "inventory_scroll"
scroll amount 10 id "inventory_scroll" pos (0.5, 0.5)
scroll # scrolls down at the current mouse position

Note

This only simulates the mousewheel event. You may consider using the Scroll action from Screen Actions, Values, and Functions.

run Scroll("inventory_scroll", "increase", amount="step", delay=1.0)

Keyboard Commands

Keysym

Type: Command

keysym <keysym> [selector] [pos (x, y)]

Simulate a keysym event. This includes the keys of config.keymap.

If selector and/or pos are given, the virtual test mouse is moved according to the rules of the move statement before the keysym is sent.

keysym "skip"
keysym "help"
keysym "ctrl_K_a"
keysym "K_BACKSPACE" repeat 30
keysym "pad_a_press"

Type

Type: Command

type <string> [selector] [pos (x, y)]

Types the provided string as if it was typed on the keyboard.

If selector and/or pos are given, the virtual test mouse is moved according to the rules of the move statement before the text is sent.

type "Hello, World!"

Condition Statements

Conditions are used to check whether a certain condition is true or not. They are used in condition-taking test statements like if, assert or until.

Boolean Values

Tests can use the literal boolean values True and False. These are always ready.

if True:
    click "Start"

if False:
    click "Settings" # does not execute, since the condition is always false

Boolean Operations

Conditions support the not, and and or operators. That expression may or may not be enclosed in parentheses.

assert eval (renpy.is_in_test() and screen "main_menu")
advance until "ask her right" or label "chapter_five"
click "Next" until not screen "choice"

Eval

Type: Condition

eval <expression>

Evaluates the provided python expression. This exists only to be used inside condition-taking test statements like assert, if or until.

assert eval (renpy.is_in_test() and ("Ren'Py" in renpy.version_string))

Note

Differences between a dollar-line and the eval clause:

• Eval cannot be used on a line by itself, it must be used inside a statement like if or until, while dollar-lines must be on their own line.

• A dollar-line executes any python statement, which does not necessarily have a value - for example $ import math - while the eval clause requires a return value.

Label

Type: Condition

label <labelname>

Checks if the provided Ren'Py label has been reached since the last time a test statement was executed.

Considering the following example:

run Jump("chapter_1")
assert label chapter_1 # works
assert label chapter_1 # fails

The first assert statement works because the label chapter_1 has been reached by the run Jump("chapter_1") statement. The second assert statement fails because the label chapter_1 has not been reached again since the first assert statement.

That also means the following example will not work:

run Jump("chapter_1")
advance repeat 3
assert label chapter_1 # fails

Warning

This test statement should not be confused with the Ren'Py native label statement it refers to, or with the unrelated label element used in screens.

Selector Statements

Selector statements are used to check if a certain element is on the screen, and to use that element for further actions.

Selectors are a special kind of condition.

Displayable Selector

Type: Condition, Selector

Check if a screen or element with given id is currently displayed.

It takes one parameter, the name of the screen. It takes the following properties:

screen <name>

The name of the screen to check.

id <name>

The id of the element to check.

layer <name>

The layer on which the screen is displayed. If not given, the layer is automatically determined by the screen name.

if screen "main_menu":
    click "Start"

advance until id "inventory_viewport" layer "overlay"

click "Close" until not id "close_button"

Text Selector

Type: Condition, Selector

"<text>"

The text selector takes a string which resolves to a target found on the screen. The search is performed by going through all focusable elements on the screen (which are typically buttons and the main textbox), and looking through their alt text.

This search is case-insensitive and looks for the shortest match. For example, if the string "log" is given, and the screen contains the texts "CATALOG" and "illogical", the target will be the "CATALOG" text.

# This may be in a button
skip until "Start Game"

# This may be in the main textbox
advance until "Hey, that's not fair!"

# Case-insensitive search
assert "AsK HeR RighT AwaY"

Control Statements

These statements control the flow of the test execution.

Assert

Type: Control

assert <condition> [timeout (float)]

This statement takes a condition and raise a RenpyTestAssertionError if the condition is not met at the time when the assert statement executes.

If a timeout is given, the statement will wait up to that many seconds for the condition to be met. If the condition is not met within that time, the assertion fails.

assert screen "main_menu"
assert eval some_function(args)
assert id "start_button" timeout 5.0

See also

• Python asserts

• Boolean evaluation

If

Type: Control

if <condition>

This statement executes a block of test statements if and when the provided condition is met.

Example:

if label "chapter_five":
    exit

if eval (persistent.should_advance and i_should_advance["now"]):
    advance

The elif and else statements can be used to add additional conditions to the if statement.

if eval persistent.should_advance:
    advance
elif eval i_should_advance["now"]:
    advance
else:
    click "Start"

Repeat

Type: Control

<command> repeat <number>

Repeats a statement for a given number of times. It consists of an Command statement on the left-hand side and a number of repetitions on the right-hand side, separated by the word repeat.

click "+" repeat 3
keysym "K_BACKSPACE" repeat 10
advance repeat 3

Until

Type: Control

<command> until <condition> [timeout (float or None)]

Repeats a statement until a condition is met. It consists of an Command statement on the left-hand side and a condition on the right-hand side, separated by the word until.

If and when the condition on the right is met, control is passed to the next statement. Otherwise, the left-hand statement is executed repeatedly until the condition is ready.

If a timeout is given, the statement will wait up to that many seconds for the condition to be met. If the condition is not met within that time, a RenpyTestTimeoutError is raised.

If the timeout is None, the statement will wait indefinitely for the condition to be met.

This timeout temporarily overrides the global _test.timeout setting.

advance until screen "choice"
click "Next"
advance until label "chapter_5"

skip until screen "inventory" timeout 20.0

Python Blocks And Dollar-Lines

A python block or a One-line Python Statement can be added within a testcase. Unlike in normal Ren'Py code, the python blocks don't take the in substore parameter, but it does take the hide keyword. They (both) allow execution of arbitrary python code.

Init code gets executed before the test occurs, so functions and classes defined in init python blocks can be called in test python blocks and in test dollar-lines. For example:

init python in test:
    def afunction():
        if renpy.is_in_test():
            return "test"
        return "not test"

testcase default:
    $ print(test.afunction()) # ends up in the console