FIX stop form items double duplicating (#728)

When calling `duplicate` on a form, a form field, or suchlike, the results
would be that all related items to the thing being duplicated (such as
fields for a form, or options to an editabledropdown) would be duplicated
_twice_; ie. where a form had two fields, it's new duplicate would have
four (each one occurring twice). We have stopped this in a backwards
compatible way - that is the bug was introduced with core 4.1, and this
change leaves the userforms module compatible with 4.0.

.travis.yml

@@ -7,11 +7,11 @@ env:
 matrix:
   include:
     - php: 5.6
-      env: DB=MYSQL PHPCS_TEST=1 PHPUNIT_TEST=1
+      env: DB=MYSQL RECIPE_VERSION=1.0.x-dev PHPCS_TEST=1 PHPUNIT_TEST=1
     - php: 7.0
-      env: DB=MYSQL PHPUNIT_TEST=1
+      env: DB=MYSQL RECIPE_VERSION=1.1.x-dev PHPUNIT_TEST=1
     - php: 7.1
-      env: DB=MYSQL PHPUNIT_COVERAGE_TEST=1
+      env: DB=MYSQL RECIPE_VERSION=1.x-dev PHPUNIT_COVERAGE_TEST=1
 
 before_script:
   # Init PHP
@@ -21,7 +21,7 @@ before_script:
 
   # Install composer dependencies
   - composer validate
-  - composer require --no-update silverstripe/recipe-cms:1.0.x-dev silverstripe-themes/simple:~3.2
+  - composer require --no-update silverstripe/recipe-cms:$RECIPE_VERSION
   - composer install --prefer-dist --no-interaction --no-progress --no-suggest --optimize-autoloader --verbose --profile
 
 script:

code/Model/EditableFormField.php

@@ -177,6 +177,8 @@ class EditableFormField extends DataObject
         'DisplayRules',
     ];
 
+    private static $cascade_duplicates = false;
+
     /**
      * @var bool
      */

code/Model/EditableFormField/EditableMultipleOptionField.php

@@ -118,6 +118,11 @@ class EditableMultipleOptionField extends EditableFormField
      */
     public function duplicate($doWrite = true, $manyMany = 'many_many')
     {
+        // Versioned 1.0 has a bug where [] will result in _all_ relations being duplicated
+        if ($manyMany === 'many_many' && !$this->manyMany()) {
+            $manyMany = null;
+        }
+
         $clonedNode = parent::duplicate($doWrite, $manyMany);
 
         foreach ($this->Options() as $field) {

code/UserForm.php

@@ -124,6 +124,8 @@ trait UserForm
         'EmailRecipients',
     ];
 
+    private static $cascade_duplicates = false;
+
     /**
      * @var array
      * @config

tests/Model/EditableFormFieldTest.php

@@ -137,7 +137,11 @@ class EditableFormFieldTest extends FunctionalTest
 
         $clone = $dropdown->duplicate();
 
-        $this->assertEquals($dropdown->Options()->Count(), $clone->Options()->Count());
+        $this->assertEquals(
+            $dropdown->Options()->Count(),
+            $clone->Options()->Count(),
+            "The duplicate should have contain same number of options"
+        );
 
         foreach ($clone->Options() as $option) {
             $original = $dropdown->Options()->find('Title', $option->Title);

tests/Model/UserDefinedFormTest.php

@@ -171,7 +171,7 @@ class UserDefinedFormTest extends FunctionalTest
         $result = $recipient->getEmailTemplateDropdownValues();
 
         // Installation path can be as a project when testing in Travis, so check partial match
-        $this->assertContains('email/SubmittedFormEmail', key($result));
+        $this->assertContains('email' . DIRECTORY_SEPARATOR . 'SubmittedFormEmail', key($result));
         $this->assertSame('SubmittedFormEmail', current($result));
     }