-% NITUNIT(1)
-
# NAME
-Executes the unit tests from Nit source files.
+nitunit - executes the unit tests from Nit source files.
+
+# SYNOPSIS
+
+nitunit [*options*] FILE...
+
+# DESCRIPTION
+
+Unit testing in Nit can be achieved in two ways:
+
+* using `DocUnits` in code comments or in markdown files
+* using `TestSuites` with test unit files
+
+`DocUnits` are executable pieces of code found in the documentation of groups, modules,
+classes and properties.
+They are used for documentation purpose, they should be kept simple and illustrative.
+More advanced unit testing can be done using TestSuites.
+
+`DocUnits` can also be used in any markdown files.
+
+`TestSuites` are test files coupled to a tested module.
+They contain a list of test methods called TestCase.
+
+## Working with `DocUnits`
+
+DocUnits are blocks of executable code placed in comments of modules, classes and properties.
+The execution can be verified using `assert`.
+
+Example with a class:
+
+~~~
+module foo
+# var foo = new Foo
+# assert foo.bar == 10
+class Foo
+ var bar = 10
+end
+~~~
+
+Everything used in the test must be declared.
+To test a method you have to instantiate its class:
+
+~~~
+module foo
+# var foo = new Foo
+# assert foo.bar == 10
+class Foo
+ # var foo = new Foo
+ # assert foo.baz(1, 2) == 3
+ fun baz(a, b: Int) do return a + b
+end
+~~~
+
+In a single piece of documentation, each docunit is considered a part of a single module, thus regrouped when
+tested.
+Therefore, it is possible (and recommended) to split docunits in small parts if it make the explanation easier.
+
+~~~~
+# Some example of grouped docunits
+#
+# Declare and initialize a variable `a`.
+#
+# var a = 1
+#
+# So the value of `a` can be used
+#
+# assert a == 1
+#
+# even in complex operations
+#
+# assert a + 1 == 2
+fun foo do end
+~~~~
+
+Sometime, some blocks of code has to be included in documentation but not considered by `nitunit`.
+Those blocks are distinguished by their tagged fences (untagged fences or fences tagged `nit` are considered to be docunits).
+
+~~~~
+# Some ASCII drawing
+#
+# ~~~~raw
+# @<
+# <__)
+# ~~~~
+fun foo do end
+~~~~
+
+The special fence-tag `nitish` could also be used to indicate pseudo-nit that will be ignored by nitunit but highlighted by nitdoc.
+Such `nitish` piece of code can be used to enclose examples that cannot compile or that one do not want to be automatically executed.
+
+~~~~
+# Some pseudo-nit
+#
+# ~~~~nitish
+# var a: Int = someting
+# # ...
+# if a == 1 then something else something-else
+# ~~~~
+#
+# Some code to not try to execute automatically
+#
+# ~~~~nitish
+# system("rm -rf /")
+# ~~~~
+~~~~
+
+The `nitunit` command is used to test Nit files:
+
+ $ nitunit foo.nit
+
+Groups (directories) can be given to test the documentation of the group and of all its Nit files:
+
+ $ nitunit lib/foo
+
+Finally, standard markdown documents can be checked with:
+
+ $ nitunit foo.md
+
+When testing, the environment variable `NIT_TESTING` is set to `true`.
+This flag can be used by libraries and program to prevent (or limit) the execution of dangerous pieces of code.
+
+~~~~~
+# NIT_TESTING is automatically set.
+#
+# assert "NIT_TESTING".environ == "true"
+~~~~
+
+## Working with `TestSuites`
+
+TestSuites are Nit modules that define a set of TestCases.
+
+A test suite is a module that uses the annotation `is test_suite`.
+
+It is common that a test suite focuses on testing a single module.
+In this case, the name of the test_suite is often `test_foo.nit` where `foo.nit` is the tested module.
+
+The structure of a test suite is the following:
+
+~~~~
+# test suite for module `foo`
+module test_foo is test_suite
+
+import test_suite
+import foo # can be intrude to test private things
+
+class TestFoo
+ super TestSuite
+
+ # test case for `foo::Foo::baz`
+ fun test_baz do
+ var subject = new Foo
+ assert subject.baz(1, 2) == 3
+ end
+end
+~~~~
+
+Test suite can be executed using the same `nitunit` command:
+
+ $ nitunit foo.nit
+
+`nitunit` will execute a test for each method named `test_*` in a class
+subclassing `TestSuite` so multiple tests can be executed for a single method:
+
+~~~~
+class TestFoo
+ super TestSuite
+
+ fun test_baz_1 do
+ var subject = new Foo
+ assert subject.baz(1, 2) == 3
+ end
+ fun test_baz_2 do
+ var subject = new Foo
+ assert subject.baz(1, -2) == -1
+ end
+end
+~~~~
+
+## Black Box Testing
+
+Sometimes, it is easier to validate a `TestCase` by comparing its output with a text file containing the expected result.
+
+For each TestCase `test_bar` of a TestSuite `test_mod.nit`, a corresponding file with the expected output is looked for:
+
+* "test_mod.sav/test_bar.res". I.e. test-cases grouped by test-suites.
+
+ This is the default and is useful if there is a lot of test-suites and test-cases in a directory
-# SYNOPSYS
+* "sav/test_bar.res". I.e. all test-cases grouped in a common sub-directory.
+
+ Useful if there is a lot of test-suites OR test-cases in a directory.
+
+* "test_bar.res" raw in the directory.
+
+ Useful is there is a few test-suites and test-cases in a directory.
+
+All 3 are exclusive. If more than one exists, the test-case is failed.
+
+If a corresponding file then the output of the test-case is compared with the file.
+
+The `diff(1)` command is used to perform the comparison.
+The test is failed if non-zero is returned by `diff`.
+
+~~~
+module test_mod is test_suite
+
+class TestFoo
+ super TestSuite
+
+ fun test_bar do
+ print "Hello!"
+ end
+end
+~~~
+
+Where `test_mod.sav/test_bar.res` contains
+
+~~~raw
+Hello!
+~~~
+
+If no corresponding `.res` file exists, then the output of the TestCase is ignored.
+
+To helps the management of the expected results, the option `--autosav` can be used to automatically create and update them.
+
+
+## Configuring TestSuites
+
+`TestSuite`s also provide methods to configure the test run:
+
+`before_test` and `after_test`: methods called before/after each test case.
+They can be used to factorize repetitive tasks:
+
+~~~~
+class TestFoo
+ super TestSuite
+ var subject: Foo
+ # Mandatory empty init
+ init do end
+ # Method executed before each test
+ fun before_test do
+ subject = new Foo
+ end
+ fun test_baz_1 do
+ assert subject.baz(1, 2) == 3
+ end
+ fun test_baz_2 do
+ assert subject.baz(1, -2) == -1
+ end
+end
+~~~~
+
+When using custom test attributes, an empty `init` must be declared to allow automatic test running.
+
+`before_module` and `after_module`: methods called before/after each test suite.
+They have to be declared at top level:
+
+~~~~
+module test_bdd_connector
+import bdd_connector
+# Testing the bdd_connector
+class TestConnector
+ # test cases using a server
+end
+# Method executed before testing the module
+fun before_module do
+ # start server before all test cases
+end
+# Method executed after testing the module
+fun after_module do
+ # stop server after all test cases
+end
+~~~~
+
+## Generating test suites
+
+Write test suites for big modules can be a repetitive and boring task...
+To make it easier, `nitunit` can generate test skeletons for Nit modules:
+
+ $ nitunit --gen-suite foo.nit
+
+This will generate the test suite `test_foo` containing test case stubs for all public
+methods found in `foo.nit`.
-nitunit [*options*]...
# OPTIONS
-`-W`, `--warn`
-: Show more warnings
+### `--full`
+Process also imported modules.
+
+By default, only the modules indicated on the command line are tested.
+
+With the `--full` option, all imported modules (even those in standard) are also precessed.
+
+### `-o`, `--output`
+Output name (default is 'nitunit.xml').
+
+`nitunit` produces a XML file compatible with JUnit.
+
+### `--dir`
+Working directory (default is 'nitunit.out').
+
+In order to execute the tests, nit files are generated then compiled and executed in the giver working directory.
+
+In case of success, the directory is removed.
+In case of failure, it is kept as is so files can be investigated.
+
+### `--nitc`
+nitc compiler to use.
+
+By default, nitunit tries to locate the `nitc` program with the environment variable `NITC` or heuristics.
+The option is used to indicate a specific nitc binary.
-`-w`, `--warning`
-: Show/hide a specific warning
+### `--no-act`
+Does not compile and run tests.
-`-q`, `--quiet`
-: Do not show warnings
+### `-p`, `--pattern`
+Only run test case with name that match pattern.
-`--stop-on-first-error`
-: Stop on first error
+Examples: `TestFoo`, `TestFoo*`, `TestFoo::test_foo`, `TestFoo::test_foo*`, `test_foo`, `test_foo*`
-`--no-color`
-: Do not use color to display errors and warnings
+### `--autosav`
+Automatically create/update .res files for black box testing.
-`--log`
-: Generate various log files
+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).
-`--log-dir`
-: Directory where to generate log files
+If a test-case of a test-suite passes but that some output is generated, then an expected result file is created.
-`-h`, `-?`, `--help`
-: Show Help (This screen)
+It is expected that the created/updated files are checked since the tests are considered passed.
+A VCS like `git` is often a good tool to check the creation and modification of those files.
-`--version`
-: Show version and exit
+## SUITE GENERATION
-`--set-dummy-tool`
-: Set toolname and version to DUMMY. Useful for testing
+### `--gen-suite`
+Generate test suite skeleton for a module.
-`-v`, `--verbose`
-: Verbose
+### `-f`, `--force`
+Force test generation even if file exists.
-`--bash-completion`
-: Generate bash_completion file for this program
+Any existing test suite will be overwritten.
-`--stub-man`
-: Generate a stub manpage in pandoc markdown format
+### `--private`
+Also generate test case for private methods.
-`--disable-phase`
-: DEBUG: Disable a specific phase; use `list` to get the list.
+### `--only-show`
+Only display the skeleton, do not write any file.
-`-I`, `--path`
-: Set include path for loaders (may be used more than once)
-`--only-parse`
-: Only proceed to parse step of loaders
+# ENVIRONMENT VARIABLES
-`--only-metamodel`
-: Stop after meta-model processing
+### `NITC`
-`--ignore-visibility`
-: Do not check, and produce errors, on visibility issues.
+Indicate the specific Nit compiler executable to use. See `--nitc`.
-`--full`
-: Process also imported modules
+### `NIT_TESTING`
-`-o`, `--output`
-: Output name (default is 'nitunit.xml')
+The environment variable `NIT_TESTING` is set to `true` during the execution of program tests.
+Some libraries of programs can use it to produce specific reproducible results; or just to exit their executions.
-`--dir`
-: Working directory (default is '.nitunit')
+Unit-tests may unset this environment variable to retrieve the original behavior of such piece of software.
-`--no-act`
-: Does not compile and run tests
+### `SRAND`
-`-p`, `--pattern`
-: Only run test case with name that match pattern. Examples: 'TestFoo', 'TestFoo*', 'TestFoo::test_foo', 'TestFoo::test_foo*', 'test_foo', 'test_foo*'
+In order to maximize reproducibility, `SRAND` is set to 0.
+This make the pseudo-random generator no random at all.
+See `Sys::srand` for details.
-`-t`, `--target-file`
-: Specify test suite location.
+To retrieve the randomness, unit-tests may unset this environment variable then call `srand`.
-`--gen-suite`
-: Generate test suite skeleton for a module
+### `NIT_TESTING_ID`
-`-f`, `--force`
-: Force test generation even if file exists
+Parallel executions can cause some race collisions on named resources (e.g. DB table names).
+To solve this issue, `NIT_TESTING_ID` is initialized with a distinct integer identifier that can be used to give unique names to resources.
-`--private`
-: Also generate test case for private methods
+Note: `rand` is not a recommended way to get a distinct identifier because its randomness is disabled by default. See `SRAND`.
-`--only-show`
-: Only display skeleton, do not write file
# SEE ALSO
nitlanguage / nit.git / blobdiff