Merge pull request #42 from dwyl/testing

#5 writing up piece on testing in elm

README.md

@@ -221,6 +221,45 @@ as you _really_ should be following the [principle of least privilege](https://e
 > Help Wanted summarizing the language features!
 > for now see: http://elm-lang.org/docs/syntax
 
+## Testing
+Ready to start testing?
+Simply follow these 3 steps:
+
+1) ``` npm i -g elm-test```
+
+2) ``` elm test init ```
+  This will set up your test environment and give you 7 dummy tests in your newly created test folder
+
+3) Run ```elm test``` or the **very nice** ```elm test --watch``` which will re-run your tests as you write them
+
+The general format of the tests are:
+```elm
+describe "Dummy test"
+    [ test "dummy test description" <|
+      \() ->
+        Expect.equal actualValue expectedValue
+    ]
+```
+For example:
+``` elm
+all : Test
+all =
+  describe "My first test"
+      [ test "Addition test works correctly" <|
+        \() ->
+            Expect.equal (2 + 2) 4
+      , test "Our subtraction function works correctly" <|
+        \() ->
+          -- here we are pretending we have a subtract function that takes 2 arguments
+            Expect.equal (subtract 10 5) 5
+      ]
+```
+
+More info on testing can be found [here](https://medium.com/@_rchaves_/testing-in-elm-93ad05ee1832#.3i3ibxcxz) and [here](http://package.elm-lang.org/packages/elm-community/elm-test/2.1.0)
+
+### Circle CI
+
+To set up your elm project on Circle CI, copy over our ```circle.yml``` and ```circle-dependencies.sh``` and follow the instructions on [our Circle CI tutorial](https://github.com/dwyl/learn-circleci)
 
 ## Reading
 

circle-dependencies.sh

@@ -0,0 +1,13 @@
+# Installs sysconfcpus so we can make elm compile faster
+# and limit the CPUS that elm uses to compile.
+# See: https://github.com/elm-lang/elm-compiler/issues/1473#issuecomment-245704142
+# and https://github.com/JamesHageman/whistlet-elm/blob/1bc50446987e3bcf92a9710698ae417652d7517f/circle-deps.sh
+export INSTALL_PATH="$HOME/dependencies"
+
+if [ ! -d $INSTALL_PATH/sysconfcpus/bin ]; then
+  git clone https://github.com/obmarg/libsysconfcpus.git
+  cd libsysconfcpus
+  ./configure --prefix=$INSTALL_PATH/sysconfcpus
+  make && make install
+  cd ..
+fi

circle.yml

@@ -0,0 +1,17 @@
+
+machine:
+  node:
+    version: 6.0.0
+
+general:
+  artifacts:
+    - "test"
+
+test:
+  pre:
+    - sh circle-dependencies.sh
+    - npm i -g elm
+
+# using sysconfcpus to speed up elm compiler # See: https://github.com/elm-lang/elm-compiler/issues/1473#issuecomment-245704142
+  override:
+    - ~/dependencies/sysconfcpus/bin/sysconfcpus -n 2 npm test