From c601bf6ac7304192cac242965217b7c089f37f8d Mon Sep 17 00:00:00 2001
From: Radek Czajka <radoslaw.czajka@nowoczesnapolska.org.pl>
Date: Mon, 24 Oct 2011 17:00:04 +0200
Subject: [PATCH 1/1] #1769: joining a document's history

---
 apps/catalogue/models/book.py    | 21 ++++++++++++++++++++-
 apps/catalogue/tests/__init__.py | 13 +++++++++++++
 apps/dvcs/models.py              | 13 ++++++++++++-
 apps/dvcs/tests/__init__.py      | 19 +++++++++++++++++++
 4 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/apps/catalogue/models/book.py b/apps/catalogue/models/book.py
index 94a98335..2a0d552f 100755
--- a/apps/catalogue/models/book.py
+++ b/apps/catalogue/models/book.py
@@ -4,7 +4,7 @@
 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
 #
 from django.contrib.sites.models import Site
-from django.db import models
+from django.db import models, transaction
 from django.template.loader import render_to_string
 from django.utils.translation import ugettext_lazy as _
 from slughifi import slughifi
@@ -80,6 +80,7 @@ class Book(models.Model):
         return self.public or request.user.is_authenticated()
 
     @classmethod
+    @transaction.commit_on_success
     def create(cls, creator, text, *args, **kwargs):
         b = cls.objects.create(*args, **kwargs)
         b.chunk_set.all().update(creator=creator)
@@ -91,6 +92,7 @@ class Book(models.Model):
         return self.chunk_set.reverse()[0].split(*args, **kwargs)
 
     @classmethod
+    @transaction.commit_on_success
     def import_xml_text(cls, text=u'', previous_book=None,
                 commit_args=None, **kwargs):
         """Imports a book from XML, splitting it into chunks as necessary."""
@@ -137,6 +139,7 @@ class Book(models.Model):
             i += 1
         return new_slug
 
+    @transaction.commit_on_success
     def append(self, other, slugs=None, titles=None):
         """Add all chunks of another book to self."""
         assert self != other
@@ -184,6 +187,22 @@ class Book(models.Model):
         assert not other.chunk_set.exists()
         other.delete()
 
+    @transaction.commit_on_success
+    def prepend_history(self, other):
+        """Prepend history from all the other book's chunks to own."""
+        assert self != other
+
+        for i in range(len(self), len(other)):
+            title = u"pusta część %d" % i
+            chunk = self.add(slughifi(title), title)
+            chunk.commit('')
+
+        for i in range(len(other)):
+            self[i].prepend_history(other[i])
+
+        assert not other.chunk_set.exists()
+        other.delete()
+
 
     # State & cache
     # =============
diff --git a/apps/catalogue/tests/__init__.py b/apps/catalogue/tests/__init__.py
index 9d0f36f8..b03701f8 100755
--- a/apps/catalogue/tests/__init__.py
+++ b/apps/catalogue/tests/__init__.py
@@ -57,3 +57,16 @@ class ManipulationTests(TestCase):
             self.book1.append(Book.objects.get(pk=self.book1.pk))
         self.assertEqual(Book.objects.all().count(), 2)
         self.assertEqual(len(self.book1), 1)
+
+    def test_prepend_history(self):
+        self.book1.prepend_history(self.book2)
+        self.assertEqual(Book.objects.all().count(), 1)
+        self.assertEqual(len(self.book1), 1)
+        self.assertEqual(self.book1.materialize(), 'book 1')
+
+    def test_prepend_history_to_self(self):
+        with self.assertRaises(AssertionError):
+            self.book1.prepend_history(self.book1)
+        self.assertEqual(Book.objects.all().count(), 2)
+        self.assertEqual(self.book1.materialize(), 'book 1')
+        self.assertEqual(self.book2.materialize(), 'book 2')
diff --git a/apps/dvcs/models.py b/apps/dvcs/models.py
index bb796274..3991efc8 100644
--- a/apps/dvcs/models.py
+++ b/apps/dvcs/models.py
@@ -4,7 +4,7 @@ import os.path
 from django.contrib.auth.models import User
 from django.core.files.base import ContentFile
 from django.core.files.storage import FileSystemStorage
-from django.db import models
+from django.db import models, transaction
 from django.db.models.base import ModelBase
 from django.utils.translation import ugettext_lazy as _
 from mercurial import mdiff, simplemerge
@@ -324,3 +324,14 @@ class Document(models.Model):
             return changes.order_by('-created_at')[0]
         else:
             return None
+
+    @transaction.commit_on_success
+    def prepend_history(self, other):
+        """Takes over the the other document's history and prepends to own."""
+
+        assert self != other
+        other_revs = other.change_set.all().count()
+        self.change_set.all().update(revision=models.F('revision') + other_revs)
+        other.change_set.all().update(tree=self)
+        assert not other.change_set.exists()
+        other.delete()
diff --git a/apps/dvcs/tests/__init__.py b/apps/dvcs/tests/__init__.py
index 1809a18e..868f00a3 100755
--- a/apps/dvcs/tests/__init__.py
+++ b/apps/dvcs/tests/__init__.py
@@ -157,3 +157,22 @@ class DocumentModelTests(TestCase):
         c3 = doc.commit(description="Commit B1", text=text_b1, parent=c1)
         c4 = doc.commit(description="Commit C1", text=text_c1, parent=c1)
         self.assertTextEqual(doc.materialize(), text_merged)
+
+
+    def test_prepend_history(self):
+        doc1 = ADocument.objects.create()
+        doc2 = ADocument.objects.create()
+        doc1.commit(text='Commit 1')
+        doc2.commit(text='Commit 2')
+        doc2.prepend_history(doc1)
+        self.assertEqual(ADocument.objects.all().count(), 1)
+        self.assertTextEqual(doc2.at_revision(1).materialize(), 'Commit 1')
+        self.assertTextEqual(doc2.materialize(), 'Commit 2')
+
+    def test_prepend_to_self(self):
+        doc = ADocument.objects.create()
+        doc.commit(text='Commit 1')
+        with self.assertRaises(AssertionError):
+            doc.prepend_history(doc)
+        self.assertTextEqual(doc.materialize(), 'Commit 1')
+
-- 
2.20.1