## unittest_toolchain
unittest_toolchain(name, failure_templ, file_ext, join_on, success_templ)
### Attributes
name Name; required

A unique name for this target.

failure_templ String; required
file_ext String; required
join_on String; required
success_templ String; required
## analysistest.make
analysistest.make(impl, expect_failure, attrs, config_settings)
Creates an analysis test rule from its implementation function. An analysis test verifies the behavior of a "real" rule target by examining and asserting on the providers given by the real target. Each analysis test is defined in an implementation function that must then be associated with a rule so that a target can be built. This function handles the boilerplate to create and return a test rule and captures the implementation function's name so that it can be printed in test feedback. An example of an analysis test: ``` def _your_test(ctx): env = analysistest.begin(ctx) # Assert statements go here return analysistest.end(env) your_test = analysistest.make(_your_test) ``` Recall that names of test rules must end in `_test`. ### Parameters
impl required.

The implementation function of the unit test.

expect_failure optional. default is False

If true, the analysis test will expect the target_under_test to fail. Assertions can be made on the underlying failure using asserts.expect_failure

attrs optional. default is {}

An optional dictionary to supplement the attrs passed to the unit test's `rule()` constructor.

config_settings optional. default is {}

A dictionary of configuration settings to change for the target under test and its dependencies. This may be used to essentially change 'build flags' for the target under test, and may thus be utilized to test multiple targets with different flags in a single build

## analysistest.begin
analysistest.begin(ctx)
Begins a unit test. This should be the first function called in a unit test implementation function. It initializes a "test environment" that is used to collect assertion failures so that they can be reported and logged at the end of the test. ### Parameters
ctx required.

The Skylark context. Pass the implementation function's `ctx` argument in verbatim.

## analysistest.end
analysistest.end(env)
Ends an analysis test and logs the results. This must be called and returned at the end of an analysis test implementation function so that the results are reported. ### Parameters
env required.

The test environment returned by `analysistest.begin`.

## analysistest.fail
analysistest.fail(env, msg)
Unconditionally causes the current test to fail. ### Parameters
env required.

The test environment returned by `unittest.begin`.

msg required.

The message to log describing the failure.

## analysistest.target_actions
analysistest.target_actions(env)
Returns a list of actions registered by the target under test. ### Parameters
env required.

The test environment returned by `analysistest.begin`.

## analysistest.target_under_test
analysistest.target_under_test(env)
Returns the target under test. ### Parameters
env required.

The test environment returned by `analysistest.begin`.

## asserts.expect_failure
asserts.expect_failure(env, expected_failure_msg)
Asserts that the target under test has failed with a given error message. This requires that the analysis test is created with `analysistest.make()` and `expect_failures = True` is specified. ### Parameters
env required.

The test environment returned by `analysistest.begin`.

expected_failure_msg optional. default is ""

The error message to expect as a result of analysis failures.

## asserts.equals
asserts.equals(env, expected, actual, msg)
Asserts that the given `expected` and `actual` values are equal. ### Parameters
env required.

The test environment returned by `unittest.begin`.

expected required.

The expected value of some computation.

actual required.

The actual value returned by some computation.

msg optional. default is None

An optional message that will be printed that describes the failure. If omitted, a default will be used.

## asserts.false
asserts.false(env, condition, msg)
Asserts that the given `condition` is false. ### Parameters
env required.

The test environment returned by `unittest.begin`.

condition required.

A value that will be evaluated in a Boolean context.

msg optional. default is "Expected condition to be false, but was true."

An optional message that will be printed that describes the failure. If omitted, a default will be used.

## asserts.set_equals
asserts.set_equals(env, expected, actual, msg)
Asserts that the given `expected` and `actual` sets are equal. ### Parameters
env required.

The test environment returned by `unittest.begin`.

expected required.

The expected set resulting from some computation.

actual required.

The actual set returned by some computation.

msg optional. default is None

An optional message that will be printed that describes the failure. If omitted, a default will be used.

## asserts.new_set_equals
asserts.new_set_equals(env, expected, actual, msg)
Asserts that the given `expected` and `actual` sets are equal. ### Parameters
env required.

The test environment returned by `unittest.begin`.

expected required.

The expected set resulting from some computation.

actual required.

The actual set returned by some computation.

msg optional. default is None

An optional message that will be printed that describes the failure. If omitted, a default will be used.

## asserts.true
asserts.true(env, condition, msg)
Asserts that the given `condition` is true. ### Parameters
env required.

The test environment returned by `unittest.begin`.

condition required.

A value that will be evaluated in a Boolean context.

msg optional. default is "Expected condition to be true, but was false."

An optional message that will be printed that describes the failure. If omitted, a default will be used.

## register_unittest_toolchains
register_unittest_toolchains()
Registers the toolchains for unittest users. ## unittest.make
unittest.make(impl, attrs)
Creates a unit test rule from its implementation function. Each unit test is defined in an implementation function that must then be associated with a rule so that a target can be built. This function handles the boilerplate to create and return a test rule and captures the implementation function's name so that it can be printed in test feedback. The optional `attrs` argument can be used to define dependencies for this test, in order to form unit tests of rules. An example of a unit test: ``` def _your_test(ctx): env = unittest.begin(ctx) # Assert statements go here return unittest.end(env) your_test = unittest.make(_your_test) ``` Recall that names of test rules must end in `_test`. ### Parameters
impl required.

The implementation function of the unit test.

attrs optional. default is {}

An optional dictionary to supplement the attrs passed to the unit test's `rule()` constructor.

## unittest.suite
unittest.suite(name, test_rules)
Defines a `test_suite` target that contains multiple tests. After defining your test rules in a `.bzl` file, you need to create targets from those rules so that `blaze test` can execute them. Doing this manually in a BUILD file would consist of listing each test in your `load` statement and then creating each target one by one. To reduce duplication, we recommend writing a macro in your `.bzl` file to instantiate all targets, and calling that macro from your BUILD file so you only have to load one symbol. For the case where your unit tests do not take any (non-default) attributes -- i.e., if your unit tests do not test rules -- you can use this function to create the targets and wrap them in a single test_suite target. In your `.bzl` file, write: ``` def your_test_suite(): unittest.suite( "your_test_suite", your_test, your_other_test, yet_another_test, ) ``` Then, in your `BUILD` file, simply load the macro and invoke it to have all of the targets created: ``` load("//path/to/your/package:tests.bzl", "your_test_suite") your_test_suite() ``` If you pass _N_ unit test rules to `unittest.suite`, _N_ + 1 targets will be created: a `test_suite` target named `${name}` (where `${name}` is the name argument passed in here) and targets named `${name}_test_${i}`, where `${i}` is the index of the test in the `test_rules` list, which is used to uniquely name each target. ### Parameters
name required.

The name of the `test_suite` target, and the prefix of all the test target names.

test_rules optional.

A list of test rules defines by `unittest.test`.

## unittest.begin
unittest.begin(ctx)
Begins a unit test. This should be the first function called in a unit test implementation function. It initializes a "test environment" that is used to collect assertion failures so that they can be reported and logged at the end of the test. ### Parameters
ctx required.

The Skylark context. Pass the implementation function's `ctx` argument in verbatim.

## unittest.end
unittest.end(env)
Ends a unit test and logs the results. This must be called and returned at the end of a unit test implementation function so that the results are reported. ### Parameters
env required.

The test environment returned by `unittest.begin`.

## unittest.fail
unittest.fail(env, msg)
Unconditionally causes the current test to fail. ### Parameters
env required.

The test environment returned by `unittest.begin`.

msg required.

The message to log describing the failure.