178 lines
6.2 KiB
Markdown
178 lines
6.2 KiB
Markdown
__ _
|
|
__ ____________/ /_ (_)___
|
|
/ / / / ___/ ___/ __ \/ / __ \
|
|
/ /_/ / / / /__/ / / / / / / /
|
|
\__,_/_/ \___/_/ /_/_/_/ /_/
|
|
|
|
Urchin is a file-based test harness, normally used for testing shell programs.
|
|
It is written in portable shell and should thus work on GNU/Linux, BSD
|
|
(including Mac OS X), and other Unix-like platforms.
|
|
|
|
Urchin is called "Urchin" because
|
|
[sea urchins](https://en.wikipedia.org/wiki/Sea_urchin)
|
|
have shells called "tests".
|
|
|
|
## Try it out
|
|
Urchin's tests are written in Urchin, so you can run them to see what Urchin
|
|
is like. Clone the repository
|
|
|
|
git clone git://github.com/tlevine/urchin.git
|
|
|
|
Run the tests
|
|
|
|
cd urchin
|
|
./urchin tests
|
|
|
|
The above command will run the tests in your system's default
|
|
shell, /bin/sh (on recent Ubuntu this is dash, but it could be
|
|
ksh or bash on other systems); to test urchin's cross-shell compatibility,
|
|
run this:
|
|
|
|
cd urchin
|
|
./cross-shell-tests
|
|
|
|
## Install
|
|
Urchin is contained in a single file, so you can install it by copying it to a
|
|
directory in your `PATH`. For example, you can run the following as root.
|
|
|
|
cd /usr/local/bin
|
|
wget https://raw.github.com/tlevine/urchin/master/urchin
|
|
chmod +x urchin
|
|
|
|
Urchin can be installed with npm too.
|
|
|
|
npm install -g urchin
|
|
|
|
Now you can run it.
|
|
|
|
urchin <test directory>
|
|
|
|
Run `urchin -h` to get command-line help.
|
|
|
|
## Writing tests
|
|
Make a root directory for your tests. Inside it, put executable files that
|
|
exit `0` on success and something else on fail. Non-executable files and hidden
|
|
files (dotfiles) are ignored, so you can store fixtures right next to your
|
|
tests. Run urchin from inside the tests directory.
|
|
|
|
Urchin only cares about the exit status, so you can actually write your tests
|
|
in any language, not just shell.
|
|
|
|
## More about writing tests
|
|
Tests are organized recursively in directories, where the names of the files
|
|
and directories have special meanings.
|
|
|
|
tests/
|
|
setup
|
|
setup_dir
|
|
bar/
|
|
setup
|
|
test_that_something_works
|
|
teardown
|
|
baz/
|
|
jack-in-the-box/
|
|
setup
|
|
test_that_something_works
|
|
teardown
|
|
cat-in-the-box/
|
|
fixtures/
|
|
thingy.pdf
|
|
test_thingy
|
|
teardown
|
|
|
|
Directories are processed in a depth-first order. When a particular directory
|
|
is processed, `setup_dir` is run before everything else in the directory, including
|
|
subdirectories. `teardown_dir` is run after everything else in the directory.
|
|
|
|
A directory's `setup` file, if it exists, is run right before each test file
|
|
within the particular directory, and the `teardown` file is run right after.
|
|
|
|
Files are only run if they are executable, and files beginning with `.` are
|
|
ignored. Thus, fixtures and libraries can be included sloppily within the test
|
|
directory tree. The test passes if the file exits 0; otherwise, it fails.
|
|
|
|
Tests files and subdirectories are run in ASCIIbetical order within each
|
|
directory; that is,
|
|
urchin looks for files within a directory in the following manner.
|
|
|
|
for file in *; do
|
|
do_something_with_test_file $file
|
|
done
|
|
|
|
### Writing cross-shell compatibility tests for testing shell code
|
|
|
|
While you could write your test scripts to explicitly invoke the functionality
|
|
to test with various shells, Urchin facilitates a more flexible approach.
|
|
|
|
The specific approach depends on your test scenario:
|
|
|
|
* (a) Your test scripts _invoke_ scripts containing portable shell code.
|
|
* (b) Your scripts _source_ scripts containing portable shell code.
|
|
|
|
#### (a) Cross-shell tests with test scripts that _invoke_ shell scripts
|
|
Urchin sets the `TEST_SHELL` environment variable so that you may change the
|
|
shell with which your tests call other shell programs. To run your test
|
|
scripts in multiple shells you must call `$TEST_SHELL` in your tests and then
|
|
run urchin with the appropriate option.
|
|
|
|
In your test scripts, invoke the shell scripts to test via the shell
|
|
specified in environment variable `TEST_SHELL` rather than directly;
|
|
e.g.: `$TEST_SHELL ../foo bar` (rather than just `../foo bar`).
|
|
|
|
On invocation of Urchin, prepend a definition of environment variable
|
|
`TEST_SHELL` specifying the shell to test with, e.g.,
|
|
|
|
TEST_SHELL=zsh urchin ./tests
|
|
|
|
To test with multiple shells in sequence, use something like:
|
|
|
|
for shell in sh bash ksh zsh; do
|
|
TEST_SHELL=$shell urchin ./tests
|
|
done
|
|
|
|
If `TEST_SHELL` has no value, Urchin defines it as `/bin/sh`, so the test
|
|
scripts can rely on `$TEST_SHELL` always containing a value when Urchin runs
|
|
them.
|
|
|
|
That said, we still recommand that you account for the possibility that
|
|
`$TEST_SHELL` does not contain a value so that you may run your test scripts
|
|
without Urchin. Supporting this case is very simple; when you invoke scripts
|
|
that happen to be in the current directory, be sure to use the prefix `./`,
|
|
e.g., `$TEST_SHELL ./baz` rather than `$TEST_SHELL baz`.
|
|
|
|
#### (b) Cross-shell tests with test scripts that _source_ shell scripts
|
|
If you _source_ shell code in your test scripts, it is the test scripts
|
|
themselves that must be run with the shell specified.
|
|
|
|
Urchin supports the `-s <shell>` option, which instructs
|
|
Urchin to invoke the test scripts with the specified shell; e.g., `-s bash`.
|
|
(In addition, Urchin sets environment variable `TEST_SHELL` to the specified
|
|
shell.)
|
|
|
|
Note that only test scripts that either have no shebang line at all or
|
|
have shebang line `#!/bin/sh` are invoked with the specified shell.
|
|
This allows non-shell test scripts or test scripts for specific
|
|
shells to coexist with those whose invocation should be controlled by `-s`.
|
|
|
|
To test with multiple shells in sequence, use something like:
|
|
|
|
for shell in sh bash ksh zsh; do
|
|
urchin -s $shell ./tests
|
|
done
|
|
|
|
Also consider using [shall](https://github.com/mklement0/shall).
|
|
It does something similar, but the interface may be more intuitive.
|
|
|
|
#!/usr/bin/env shall
|
|
echo This is a test file.
|
|
|
|
## Alternatives to Urchin
|
|
Alternatives to Urchin are discussed in
|
|
[this blog post](https://blog.scraperwiki.com/2012/12/how-to-test-shell-scripts/).
|
|
|
|
## Ideas for new features
|
|
|
|
* Support [Nagios plugins](https://nagios-plugins.org/doc/guidelines.html)
|
|
* Stop running if a test fails so one can use Urchin as a
|
|
[setup framework](https://github.com/tlevine/urchin/issues/16).
|