59a516d481
Added doctests and a shout out to what is going on with "$$tablename$$" in the ``withTable`` function. Updated the level04 tests file to be a bit more defined and provide an example of a test that Hspec.Wai lets you write. Information was very thin on the ground in that file so it would have been too difficult without assistance. Provided a bit more information about cool things that ``ghcid`` can do that I didn't know about. :D Fixes #9, #7, #5 |
||
|---|---|---|
| .. | ||
| bin | ||
| src/FirstApp | ||
| tests | ||
| appconfig.json | ||
| changelog.md | ||
| default.nix | ||
| level04.cabal | ||
| level04.nix | ||
| LICENCE | ||
| README.md | ||
| Setup.hs | ||
| test.json | ||
Level 04
In this exercise we're going to add some tests to our application. Because types are awesome, and tests are pretty good. But types AND tests is pretty much perfect.
These tests will not be awe inspiring, this exercise is primarily to introduce you to adding tests to your Haskell application. The setup of the Cabal file is already completed for you, but will be covered.
As is to be expected, there are multiple testing frameworks and packages available but we will only cover one here. We will use the HSpec framework, with the hspec-wai package to make our lives a bit easier.
Start in tests/Test.hs.
Aside: Tool Introduction - ghcid
Additionally we'd like to introduce a command line tool that you may find useful for Haskell development; ghcid. This is a very lightweight tool that works for any project with a functioning cabal setup.
If you would like to use it, consult its documentation for how to install it,
and then in an spare open terminal window, navigate to the root of the Haskell
project and run $ ghcid.
It will then attempt to build your project, if errors are found they will be
displayed. But more importantly you can go back to editing files in the project
and ghcid will refresh in the background. Providing you with new error
messages or All Good if it cannot find any errors.
ghcid provides extremely fast feedback, allowing for a nice development
process with constant feedback about your changes. It is very useful in tandem
with type holes. Give it a try!
ghcid can also help out when you're writing your tests. Since normally the
source and other packages that are listed in a test-suite configuration
section in the Cabal file are not loaded. You can manually tell ghcid to
load and examine these files with the following command:
$ ghcid -c "cabal repl level0N-tests"'