3 nitunit - executes the unit tests from Nit source files.
7 nitunit [*options*] FILE...
11 Unit testing in Nit can be achieved in two ways:
13 * using `DocUnits` in code comments or in markdown files
14 * using `TestSuites` with test unit files
16 `DocUnits` are executable pieces of code found in the documentation of groups, modules,
17 classes and properties.
18 They are used for documentation purpose, they should be kept simple and illustrative.
19 More advanced unit testing can be done using TestSuites.
21 `DocUnits` can also be used in any markdown files.
23 `TestSuites` are test files coupled to a tested module.
24 They contain a list of test methods called TestCase.
26 ## Working with `DocUnits`
28 DocUnits are blocks of executable code placed in comments of modules, classes and properties.
29 The execution can be verified using `assert`.
36 # assert foo.bar == 10
42 Everything used in the test must be declared.
43 To test a method you have to instantiate its class:
48 # assert foo.bar == 10
51 # assert foo.baz(1, 2) == 3
52 fun baz(a, b: Int) do return a + b
56 In a single piece of documentation, each docunit is considered a part of a single module, thus regrouped when
58 Therefore, it is possible (and recommended) to split docunits in small parts if it make the explanation easier.
61 # Some example of grouped docunits
63 # Declare and initialize a variable `a`.
67 # So the value of `a` can be used
71 # even in complex operations
77 Sometime, some blocks of code has to be included in documentation but not considered by `nitunit`.
78 Those blocks are distinguished by their tagged fences (untagged fences or fences tagged `nit` are considered to be docunits).
90 The special fence-tag `nitish` could also be used to indicate pseudo-nit that will be ignored by nitunit but highlighted by nitdoc.
91 Such `nitish` piece of code can be used to enclose examples that cannot compile or that one do not want to be automatically executed.
97 # var a: Int = someting
99 # if a == 1 then something else something-else
102 # Some code to not try to execute automatically
109 The `nitunit` command is used to test Nit files:
113 Groups (directories) can be given to test the documentation of the group and of all its Nit files:
117 Finally, standard markdown documents can be checked with:
121 When testing, the environment variable `NIT_TESTING` is set to `true`.
122 This flag can be used by libraries and program to prevent (or limit) the execution of dangerous pieces of code.
125 # NIT_TESTING is automatically set.
127 # assert "NIT_TESTING".environ == "true"
130 ## Working with `TestSuites`
132 TestSuites are Nit files that define a set of TestCases for a particular module.
134 The test suite must be called `test_` followed by the name of the module to test.
135 So for the module `foo.nit` the test suite will be called `test_foo.nit`.
137 The structure of a test suite is the following:
140 # test suite for module `foo`
142 import foo # can be intrude to test private things
144 # test case for `foo::Foo::baz`
146 var subject = new Foo
147 assert subject.baz(1, 2) == 3
152 Test suite can be executed using the same `nitunit` command:
156 `nitunit` will execute a test for each method named `test_*` in a class named `Test*`
157 so multiple tests can be executed for a single method:
162 var subject = new Foo
163 assert subject.baz(1, 2) == 3
166 var subject = new Foo
167 assert subject.baz(1, -2) == -1
174 Sometimes, it is easier to validate a `TestCase` by comparing its output with a text file containing the expected result.
176 For each TestCase `test_bar` of a TestSuite `test_mod.nit`, a corresponding file with the expected output is looked for:
178 * "test_mod.sav/test_bar.res". I.e. test-cases grouped by test-suites.
180 This is the default and is useful if there is a lot of test-suites and test-cases in a directory
182 * "sav/test_bar.res". I.e. all test-cases grouped in a common sub-directory.
184 Useful if there is a lot of test-suites OR test-cases in a directory.
186 * "test_bar.res" raw in the directory.
188 Useful is there is a few test-suites and test-cases in a directory.
190 All 3 are exclusive. If more than one exists, the test-case is failed.
192 If a corresponding file then the output of the test-case is compared with the file.
194 The `diff(1)` command is used to perform the comparison.
195 The test is failed if non-zero is returned by `diff`.
198 module test_mod is test_suite
206 Where `test_mod.sav/test_bar.res` contains
212 If no corresponding `.res` file exists, then the output of the TestCase is ignored.
214 To helps the management of the expected results, the option `--autosav` can be used to automatically create and update them.
217 ## Configuring TestSuites
219 `TestSuites` also provide methods to configure the test run:
221 `before_test` and `after_test`: methods called before/after each test case.
222 They can be used to factorize repetitive tasks:
227 # Mandatory empty init
229 # Method executed before each test
234 assert subject.baz(1, 2) == 3
237 assert subject.baz(1, -2) == -1
242 When using custom test attributes, an empty `init` must be declared to allow automatic test running.
244 `before_module` and `after_module`: methods called before/after each test suite.
245 They have to be declared at top level:
248 module test_bdd_connector
250 # Testing the bdd_connector
252 # test cases using a server
254 # Method executed before testing the module
256 # start server before all test cases
258 # Method executed after testing the module
260 # stop server after all test cases
264 ## Generating test suites
266 Write test suites for big modules can be a repetitive and boring task...
267 To make it easier, `nitunit` can generate test skeletons for Nit modules:
269 $ nitunit --gen-suite foo.nit
271 This will generate the test suite `test_foo` containing test case stubs for all public
272 methods found in `foo.nit`.
278 Process also imported modules.
280 By default, only the modules indicated on the command line are tested.
282 With the `--full` option, all imported modules (even those in standard) are also precessed.
285 Output name (default is 'nitunit.xml').
287 `nitunit` produces a XML file compatible with JUnit.
290 Working directory (default is 'nitunit.out').
292 In order to execute the tests, nit files are generated then compiled and executed in the giver working directory.
294 In case of success, the directory is removed.
295 In case of failure, it is kept as is so files can be investigated.
298 nitc compiler to use.
300 By default, nitunit tries to locate the `nitc` program with the environment variable `NITC` or heuristics.
301 The option is used to indicate a specific nitc binary.
304 Does not compile and run tests.
306 ### `-p`, `--pattern`
307 Only run test case with name that match pattern.
309 Examples: `TestFoo`, `TestFoo*`, `TestFoo::test_foo`, `TestFoo::test_foo*`, `test_foo`, `test_foo*`
311 ### `-t`, `--target-file`
312 Specify test suite location.
315 Automatically create/update .res files for black box testing.
317 If a black block test fails because a difference between the expected result and the current result then the expected result file is updated (and the test is passed).
319 If a test-case of a test-suite passes but that some output is generated, then an expected result file is created.
321 It is expected that the created/updated files are checked since the tests are considered passed.
322 A VCS like `git` is often a good tool to check the creation and modification of those files.
327 Generate test suite skeleton for a module.
330 Force test generation even if file exists.
332 Any existing test suite will be overwritten.
335 Also generate test case for private methods.
338 Only display the skeleton, do not write any file.
341 # ENVIRONMENT VARIABLES
345 Indicate the specific Nit compiler executable to use. See `--nitc`.
349 The environment variable `NIT_TESTING` is set to `true` during the execution of program tests.
350 Some libraries of programs can use it to produce specific reproducible results; or just to exit their executions.
352 Unit-tests may unset this environment variable to retrieve the original behavior of such piece of software.
356 In order to maximize reproducibility, `SRAND` is set to 0.
357 This make the pseudo-random generator no random at all.
358 See `Sys::srand` for details.
360 To retrieve the randomness, unit-tests may unset this environment variable then call `srand`.
364 Parallel executions can cause some race collisions on named resources (e.g. DB table names).
365 To solve this issue, `NIT_TESTING_ID` is initialized with a distinct integer identifier that can be used to give unique names to resources.
367 Note: `rand` is not a recommended way to get a distinct identifier because its randomness is disabled by default. See `SRAND`.
372 The Nit language documentation and the source code of its tools and libraries may be downloaded from <http://nitlanguage.org>