docshtest 0.0.3

QuickStart

docshtest is a doctest for shell command. This means it allows you to integrate in your documentation some examples of shell code and their expected output that will be actually verifiable.

First please notice that these documentation lines you are reading are stored in a README.rst file that will contain very soon some examples of how to run docshtest and what outcome to expect.

The very first example that comes to mind is to run docshtest on this very documentation:

docshtest README.rst

You can check that yourself, and that’s done in the CI procedures.

Let’s introduce you the basics of writing your own testable documentation…

So this is how it works:

$ cat <<'EOF' > mydoc.rst   ## First test file

This is standard RST, we can include runnable test blocks::

    $ echo 'hello world'
    hello world

EOF

Note that indentation is required, as well as the "$ " (dollar sign followed by a space) before the command to be executed. Please refer to the following section to understand how docshtest figures out the end of your shell code and the start of the output.

The output starts after the end of your command, indented also, and will be matched with the actual command output. If there is a mismatch the test will fail, and docshtest will cancel any remaining tests. If it matches, next test block will be executed.

To run our test:

$ ./docshtest mydoc.rst
#0001 - success (line          4)

Multiline Commands

Multiline commands are detected with a very simple, but dirty method, docshtest will simply provide the exact code, starting with only the first line to the shell interpreter, if the shell interpreter complains, it’ll try again by adding the next line to the output.

This allows to document/test multi-line shell codes like:

$ cat <<EOF > mydoc.rst   ## First test file

Multiline commands::

    $ for a in \$(seq 1 3); do
        echo "foo\$a"
      done
    foo1
    foo2
    foo3

EOF
$ ./docshtest mydoc.rst
#0001 - success (lines       4-6)

Please note that the extra indentation for the body of the for loop or the done is unnecessary, but is recommended for reading:

$ cat <<EOF > mydoc.rst   ## First test file

Multiline commands::

    $ for a in \$(seq 1 3); do
      echo "foo\$a"
    done
    foo1
    foo2
    foo3

EOF
$ ./docshtest mydoc.rst
#0001 - success (lines       4-6)

Failing test will display both expected output and current output:

$ cat <<EOF > mydoc.rst   ## First test file

Multiline commands::

    $ for a in \$(seq 1 3); do
      echo "foo\$a"
    done
    foo1
    foo4
    foo3

EOF
$ ./docshtest mydoc.rst
#0001 - failure (lines       4-6):
  command:
  | for a in $(seq 1 3); do
  |   echo "foo$a"
  | done
  expected:
  | foo1
  | foo4
  | foo3
  |
  output:
  | foo1
  | foo2
  | foo3
  |

But note that if these outputs are bigger, a standard unified diff will be printed:

$ cat <<EOF > mydoc.rst   ## First test file

Multiline commands::

    $ for a in \$(seq 1 6); do
      echo "foo\$a"
    done
    foo1
    foo3
    foo4
    foo5
    foo6

EOF
$ ./docshtest mydoc.rst
#0001 - failure (lines       4-6):
  command:
  | for a in $(seq 1 6); do
  |   echo "foo$a"
  | done
  expected:
  | foo1
  | foo3
  | foo4
  | foo5
  | foo6
  |
  output:
  | foo1
  | foo2
  | foo3
  | foo4
  | foo5
  | foo6
  |
  diff:
  --- expected
  +++ output
  @@ -1,4 +1,5 @@
   foo1
  +foo2
   foo3
   foo4
   foo5

Tinkering all executed code

You can transform all executed code before execution thanks to --regex REGEX (or -r REGEX) option:

$ cat <<'EOF' > mydoc.rst   ## First test file

Our tested command is 'foo'

    $ foo 'hello world'
    hello world

EOF
$ ./docshtest -r '#\bfoo\b#echo#' mydoc.rst
#0001 - success (line          4)

Conditional Tests

You might want to have conditional tests, that are triggered only on if specific test succeeds. This feature uses meta commands that are specified as shell comments in the given block:

$ cat <<'EOF' > mydoc.rst

Our tested command is 'foo'

    $ echo $ENVVAR       ## docshtest: if-success-set VAR_WAS_SET
    0
    $ echo 'var is set'  ## docshtest: ignore-if VAR_WAS_SET
    SHOULDFAIL
    $ echo 'var is not set'  ## docshtest: ignore-if-not VAR_WAS_SET
    SHOULDFAIL

EOF
$ ENVVAR=0 ./docshtest mydoc.rst
#0001 - ignored (line          4): if-success-set VAR_WAS_SET
#0002 - ignored (line          6): ignore-if VAR_WAS_SET
#0003 - failure (line          8):
  command:
  | echo 'var is not set'  ## docshtest: ignore-if-not VAR_WAS_SET
  expected:
  | SHOULDFAIL
  |
  output:
  | var is not set
  |

Encoding

docshtest will assume everything is “UTF-8”:

$ cat <<'EOF' > mydoc.rst

Our tested command is 'foo'

    $ echo "éà"
    éà
    $ echo "é"
    e

EOF

$ ./docshtest mydoc.rst
#0001 - success (line          4)
#0002 - failure (line          6):
  command:
  | echo "é"
  expected:
  | e
  |
  output:
  | é
  |

Command line

docshtest supports the common GNU standard --help options:

$ ./docshtest --help

docshtest - parse file and run shell doctests

Usage:

    docshtest (-h|--help)
    docshtest [[-r|--regex REGEX] ...] DOCSHTEST_FILE


Options:

    -r REGEX, --regex REGEX
              Will apply this regex to the lines to be executed. You
              can have more than one patterns by re-using this options
              as many times as wanted. Regexps will be applied one by one
              in the same order than they are provided on the command line.


Examples:

     ## run tests but replace executable on-the-fly for coverage support
     docshtest README.rst -r '/\bdocshtest\b/coverage run docshtest.py/'
<BLANKLINE>
<BLANKLINE>

First argument is necessary:

$ ./docshtest
Error: please provide a rst filename as argument. (use '--help' option to get usage info)

And of course it should be the path of a file:

$ ./docshtest notexistent
Error: file 'notexistent' not found.

Push Request Guidelines

You can send any code. I’ll look at it and will integrate it myself in the code base and leave you as the author. This process can take time and it’ll take less time if you follow the following guidelines:

• Try to stick to 80 columns wide.

• separate your commits per smallest concern.

• each commit should pass the tests (to allow easy bisect)

• each functionality/bugfix commit should contain the code, tests, and doc.

• prior minor commit with typographic or code cosmetic changes are very welcome. These should be tagged in their commit summary with !minor.

• the commit message should follow gitchangelog rules (check the git log to get examples)

• if the commit fixes an issue or finished the implementation of a feature, please mention it in the summary.

If you have some questions about guidelines which is not answered here, please check the current git log, you might find previous commit that would show you how to deal with your issue.

0.0.3 (2020-12-14)

Fix

• Support utf-8 encoding. [Valentin Lab]

0.0.1 (2019-02-11)

• First import. [Valentin Lab]