usage.md

Usage

Bats comes with two manual pages. After installation you can view them with man 1 bats (usage manual) and man 7 bats (writing test files manual). Also, you can view the available command line options that Bats supports by calling Bats with the -h or --help options. These are the options that Bats currently supports:

.. program-output:: ../../bin/bats --help

To run your tests, invoke the bats interpreter with one or more paths to test files ending with the .bats extension, or paths to directories containing test files. (bats will only execute .bats files at the top level of each directory; it will not recurse unless you specify the -r flag.)

Test cases from each file are run sequentially and in isolation. If all the test cases pass, bats exits with a 0 status code. If there are any failures, bats exits with a 1 status code.

When you run Bats from a terminal, you'll see output as each test is performed, with a check-mark next to the test's name if it passes or an "X" if it fails.

$ bats addition.bats
 ✓ addition using bc
 ✓ addition using dc

2 tests, 0 failures

If Bats is not connected to a terminal—in other words, if you run it from a continuous integration system, or redirect its output to a file—the results are displayed in human-readable, machine-parsable TAP format.

You can force TAP output from a terminal by invoking Bats with the --formatter tap option.

$ bats --formatter tap addition.bats
1..2
ok 1 addition using bc
ok 2 addition using dc

With --formatter junit, it is possible to output junit-compatible report files.

$ bats --formatter junit addition.bats
1..2
ok 1 addition using bc
ok 2 addition using dc

If you have your own formatter, you can use an absolute path to the executable to use it:

$ bats --formatter /absolute/path/to/my-formatter addition.bats
addition using bc WORKED
addition using dc FAILED

You can also generate test report files via --report-formatter which accepts the same options as --formatter. By default, the file is stored in the current workdir. However, it may be placed elsewhere by specifying the --output flag.

$ bats --report-formatter junit addition.bats --output /tmp
1..2
ok 1 addition using bc
ok 2 addition using dc

$ cat /tmp/report.xml
<?xml version="1.0" encoding="UTF-8"?>
<testsuites time="0.073">
<testsuite name="addition.bats" tests="2" failures="0" errors="0" skipped="0">
    <testcase classname="addition.bats" name="addition using bc" time="0.034" />
    <testcase classname="addition.bats" name="addition using dc" time="0.039" />
</testsuite>
</testsuites>

Parallel Execution

.. versionadded:: 1.0.0

By default, Bats will execute your tests serially. However, Bats supports parallel execution of tests (provided you have GNU parallel or a compatible replacement installed) using the --jobs parameter. This can result in your tests completing faster (depending on your tests and the testing hardware).

Ordering of parallelised tests is not guaranteed, so this mode may break suites with dependencies between tests (or tests that write to shared locations). When enabling --jobs for the first time be sure to re-run bats multiple times to identify any inter-test dependencies or non-deterministic test behaviour.

When parallelizing, the results of a file only become visible after it has been finished. You can use --no-parallelize-across-files to get immediate output at the cost of reduced overall parallelity, as parallelization will only happen within files and files will be run sequentially.

If you have files where tests within the file would interfere with each other, you can use --no-parallelize-within-files to disable parallelization within all files. If you want more fine-grained control, you can export BATS_NO_PARALLELIZE_WITHIN_FILE=true in setup_file() or outside any function to disable parallelization only within the containing file.