Add test with vader

Author: alquerci

.gitignore

@@ -0,0 +1 @@
+/vendor

README.md

@@ -381,3 +381,12 @@ class Foo {
 `<Leader>da` will call your documentation plugin (by default Php Documentor for vim https://github.com/tobyS/pdv) for every uncommented classes, methods, functions and properties.
 
 
+## Running tests
+
+```
+bin/test
+```
+
+### How to write tests?
+
+See https://github.com/junegunn/vader.vim

bin/test

@@ -0,0 +1,31 @@
+#! /bin/sh -eu
+
+installVader ()
+{
+    vaderdir='vendor/vader.vim'
+    vaderCommit='6fff477431ac3191c69a3a5e5f187925466e275a'
+
+    test -d "$vaderdir" || {
+        {
+            git clone \
+                --branch=master \
+                --single-branch \
+                https://github.com/junegunn/vader.vim.git \
+                "$vaderdir"
+
+            git \
+                --work-tree="$vaderdir" \
+                --git-dir="$vaderdir/.git" \
+                reset --hard \
+                "$vaderCommit" --
+        } || {
+            rm -rf "$vaderdir"
+
+            exit 1
+        }
+    }
+}
+
+installVader
+
+vim -esNu test/fixtures/vimrc -c 'Vader! test/*'

test/extract_variable.vader

@@ -0,0 +1,61 @@
+Given php (condition on if):
+  <?php
+
+  $sentence = 'Hello';
+
+  if ('foo' === $firstName) {
+      $sentence .= ' ' . $firstName;
+  }
+
+Do (select the condition and extract variable):
+  /foo\<CR>
+  vi(
+  ;ev
+  firstNameIsValid\<CR>
+
+Expect php (variable is extracted):
+  <?php
+
+  $sentence = 'Hello';
+
+  $firstNameIsValid = 'foo' === $firstName;
+
+  if ($firstNameIsValid) {
+      $sentence .= ' ' . $firstName;
+  }
+
+Given php (condition on if and on function):
+  <?php
+
+  function prepareSentence()
+  {
+      $sentence = 'Hello';
+
+      if ('foo' === $firstName) {
+          $sentence .= ' ' . $firstName;
+      }
+
+      return $sentence;
+  }
+
+Do (select the condition and extract variable):
+  /foo\<CR>
+  vi(
+  ;ev
+  firstNameIsValid\<CR>
+
+Expect php (variable is extracted):
+  <?php
+
+  function prepareSentence()
+  {
+      $sentence = 'Hello';
+
+      $firstNameIsValid = 'foo' === $firstName;
+
+      if ($firstNameIsValid) {
+          $sentence .= ' ' . $firstName;
+      }
+
+      return $sentence;
+  }

test/fixtures/vimrc

@@ -0,0 +1,14 @@
+" Setup a testing environment that is isolated from the other plugins.
+"
+filetype off
+
+set rtp+=vendor/vader.vim
+set rtp+=.
+set rtp+=after
+
+filetype plugin on
+filetype indent on
+
+syntax enable
+
+let mapleader = ";"