Move subtask forecast to a plugin

Plugin repo: https://github.com/kanboard/plugin-subtask-forecast

tests/units/Core/Plugin/HookTest.php

@@ -0,0 +1,62 @@
+<?php
+
+require_once __DIR__.'/../../Base.php';
+
+use Core\Plugin\Hook;
+
+class HookTest extends Base
+{
+    public function testGetListeners()
+    {
+        $h = new Hook;
+        $this->assertEmpty($h->getListeners('myhook'));
+
+        $h->on('myhook', 'A');
+        $h->on('myhook', 'B');
+
+        $this->assertEquals(array('A', 'B'), $h->getListeners('myhook'));
+    }
+
+    public function testMergeWithNoBinding()
+    {
+        $h = new Hook;
+        $values = array('A', 'B');
+
+        $result = $h->merge('myhook', $values, array('p' => 'c'));
+        $this->assertEquals($values, $result);
+    }
+
+    public function testMergeWithBindings()
+    {
+        $h = new Hook;
+        $values = array('A', 'B');
+        $expected = array('A', 'B', 'c', 'D');
+
+        $h->on('myhook', function($p) {
+            return array($p);
+        });
+
+        $h->on('myhook', function() {
+            return array('D');
+        });
+
+        $result = $h->merge('myhook', $values, array('p' => 'c'));
+        $this->assertEquals($expected, $result);
+        $this->assertEquals($expected, $values);
+    }
+
+    public function testMergeWithBindingButReturningBadData()
+    {
+        $h = new Hook;
+        $values = array('A', 'B');
+        $expected = array('A', 'B');
+
+        $h->on('myhook', function() {
+            return 'string';
+        });
+
+        $result = $h->merge('myhook', $values);
+        $this->assertEquals($expected, $result);
+        $this->assertEquals($expected, $values);
+    }
+}

tests/units/Helper/HookHelperTest.php

@@ -0,0 +1,40 @@
+<?php
+
+require_once __DIR__.'/../Base.php';
+
+use Helper\Hook;
+
+class HookHelperTest extends Base
+{
+    public function testMultipleHooks()
+    {
+        $this->container['template'] = $this
+            ->getMockBuilder('\Core\Template')
+            ->setConstructorArgs(array($this->container))
+            ->setMethods(array('render'))
+            ->getMock();
+
+        $this->container['template']
+            ->expects($this->at(0))
+            ->method('render')
+            ->with(
+                $this->equalTo('tpl1'),
+                $this->equalTo(array())
+            )
+            ->will($this->returnValue('tpl1_content'));
+
+        $this->container['template']
+            ->expects($this->at(1))
+            ->method('render')
+            ->with(
+                $this->equalTo('tpl2'),
+                $this->equalTo(array())
+            )
+            ->will($this->returnValue('tpl2_content'));
+
+        $h = new Hook($this->container);
+        $h->attach('test', 'tpl1');
+        $h->attach('test', 'tpl2');
+        $this->assertEquals('tpl1_contenttpl2_content', $h->render('test'));
+    }
+}