mirror of
https://github.com/Xevion/exercism.git
synced 2025-12-08 06:07:00 -06:00
61 lines
2.4 KiB
Markdown
61 lines
2.4 KiB
Markdown
# Ledger
|
|
|
|
Refactor a ledger printer.
|
|
|
|
The ledger exercise is a refactoring exercise. There is code that prints a
|
|
nicely formatted ledger, given a locale (American or Dutch) and a currency (US
|
|
dollar or euro). The code however is rather badly written, though (somewhat
|
|
surprisingly) it consistently passes the test suite.
|
|
|
|
Rewrite this code. Remember that in refactoring the trick is to make small steps
|
|
that keep the tests passing. That way you can always quickly go back to a
|
|
working version. Version control tools like git can help here as well.
|
|
|
|
Please keep a log of what changes you've made and make a comment on the exercise
|
|
containing that log, this will help reviewers.
|
|
|
|
## Exception messages
|
|
|
|
Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to
|
|
indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not
|
|
every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include
|
|
a message.
|
|
|
|
To raise a message with an exception, just write it as an argument to the exception type. For example, instead of
|
|
`raise Exception`, you should write:
|
|
|
|
```python
|
|
raise Exception("Meaningful message indicating the source of the error")
|
|
```
|
|
|
|
## Running the tests
|
|
|
|
To run the tests, run the appropriate command below ([why they are different](https://github.com/pytest-dev/pytest/issues/1629#issue-161422224)):
|
|
|
|
- Python 2.7: `py.test ledger_test.py`
|
|
- Python 3.4+: `pytest ledger_test.py`
|
|
|
|
Alternatively, you can tell Python to run the pytest module (allowing the same command to be used regardless of Python version):
|
|
`python -m pytest ledger_test.py`
|
|
|
|
### Common `pytest` options
|
|
|
|
- `-v` : enable verbose output
|
|
- `-x` : stop running tests on first failure
|
|
- `--ff` : run failures from previous test before running other test cases
|
|
|
|
For other options, see `python -m pytest -h`
|
|
|
|
## Submitting Exercises
|
|
|
|
Note that, when trying to submit an exercise, make sure the solution is in the `$EXERCISM_WORKSPACE/python/ledger` directory.
|
|
|
|
You can find your Exercism workspace by running `exercism debug` and looking for the line that starts with `Workspace`.
|
|
|
|
For more detailed information about running tests, code style and linting,
|
|
please see [Running the Tests](http://exercism.io/tracks/python/tests).
|
|
|
|
## Submitting Incomplete Solutions
|
|
|
|
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
|