From 85902d111db2a11c4ac93344a615a230e9124c76 Mon Sep 17 00:00:00 2001
From: Matt Westcott <matt@west.co.tt>
Date: Wed, 11 Feb 2015 12:39:44 +0000
Subject: [PATCH] implement SnippetChooserBlock

---
 wagtail/wagtailsnippets/blocks.py  | 17 +++++++++++++++++
 wagtail/wagtailsnippets/widgets.py |  6 +++---
 2 files changed, 20 insertions(+), 3 deletions(-)
 create mode 100644 wagtail/wagtailsnippets/blocks.py

diff --git a/wagtail/wagtailsnippets/blocks.py b/wagtail/wagtailsnippets/blocks.py
new file mode 100644
index 000000000..560cdf7f7
--- /dev/null
+++ b/wagtail/wagtailsnippets/blocks.py
@@ -0,0 +1,17 @@
+from __future__ import unicode_literals
+
+from django.utils.functional import cached_property
+from django.contrib.contenttypes.models import ContentType
+
+from wagtail.wagtailadmin.blocks import ChooserBlock
+
+class SnippetChooserBlock(ChooserBlock):
+    def __init__(self, target_model, **kwargs):
+        super(SnippetChooserBlock, self).__init__(**kwargs)
+        self.target_model = target_model
+
+    @cached_property
+    def widget(self):
+        from wagtail.wagtailsnippets.widgets import AdminSnippetChooser
+        content_type = ContentType.objects.get_for_model(self.target_model)
+        return AdminSnippetChooser(content_type)
diff --git a/wagtail/wagtailsnippets/widgets.py b/wagtail/wagtailsnippets/widgets.py
index 611efc40f..8c58e16f0 100644
--- a/wagtail/wagtailsnippets/widgets.py
+++ b/wagtail/wagtailsnippets/widgets.py
@@ -22,10 +22,10 @@ class AdminSnippetChooser(AdminChooser):
             self.target_content_type = content_type
 
     def render_html(self, name, value, attrs):
-        original_field_html = super(AdminSnippetChooser, self).render_html(name, value, attrs)
-
         model_class = self.target_content_type.model_class()
-        instance = self.get_instance(model_class, value)
+        instance, value = self.get_instance_and_id(model_class, value)
+
+        original_field_html = super(AdminSnippetChooser, self).render_html(name, value, attrs)
 
         return render_to_string("wagtailsnippets/widgets/snippet_chooser.html", {
             'widget': self,