Added tests for merges and conflicts

Author: migurski

bizarro/repo.py

@@ -1,6 +1,10 @@
 import os, logging
 from os.path import join, split
 
+class MergeConflict (Exception):
+    def __init__(self, remote_tree, local_tree):
+        pass
+
 def start_branch(clone, default_branch_name, new_branch_name):
     ''' Start a new repository branch, push it to origin and return it.
     '''
@@ -11,8 +15,9 @@ def start_branch(clone, default_branch_name, new_branch_name):
     else:
         start_point = clone.branches[default_branch_name].commit
 
+    # Start or update the branch, letting origin override the local repo.
     logging.debug('start_branch() start_point is %s' % repr(start_point))
-    branch = clone.create_head(new_branch_name, commit=start_point)
+    branch = clone.create_head(new_branch_name, commit=start_point, force=True)
     clone.remotes.origin.push(new_branch_name)
 
     return branch
@@ -49,11 +54,26 @@ def make_working_file(clone, dir, path):
     return repo_path, real_path
 
 def save_working_file(clone, path, message, base_sha):
-    ''' Save a file in the working dir and push it to origin.
+    ''' Save a file in the working dir, push it to origin, and return the commit.
     '''
     if clone.active_branch.commit.hexsha != base_sha:
         raise Exception('Out of date SHA: %s' % base_sha)
 
     clone.index.add([path])
-    clone.index.commit(message)
-    clone.remotes.origin.push(clone.active_branch.name)
+    new_commit = clone.index.commit(message)
+    branch_name = clone.active_branch.name
+    
+    try:
+        # sync: pull --rebase followed by push.
+        clone.remotes.origin.pull(branch_name, rebase=True)
+    
+    except AssertionError:
+        # raise the two trees in conflict.
+        clone.remotes.origin.fetch()
+        remote_tree = clone.refs['origin/' + branch_name].commit.tree
+        raise MergeConflict(remote_tree, new_commit.tree)
+    
+    else:
+        clone.remotes.origin.push(clone.active_branch.name)
+    
+    return clone.active_branch.commit

test.py

@@ -35,6 +35,8 @@ def test_repo_features(self):
         self.assertEqual(set(branch_names), set(['master', 'title', 'body']))
 
     def test_start_branch(self):
+        ''' Make a simple edit in a clone, verify that it appears in the other.
+        '''
         name = str(uuid4())
         branch1 = bizarro.repo.start_branch(self.clone1, 'master', name)
 
@@ -62,6 +64,8 @@ def test_start_branch(self):
         self.assertEquals(branch2.commit.message, message)
 
     def test_new_file(self):
+        ''' Make a new file in a clone, verify that it appears in the other.
+        '''
         name = str(uuid4())
         branch1 = bizarro.repo.start_branch(self.clone1, 'master', name)
 
@@ -98,6 +102,91 @@ def test_new_file(self):
             self.assertEquals(front['title'], 'Hello')
             self.assertEquals(body, 'Hello hello.')
 
+    def test_simple_merge(self):
+        ''' Test that two simultaneous non-conflicting changes merge cleanly.
+        '''
+        name = str(uuid4())
+        branch1 = bizarro.repo.start_branch(self.clone1, 'master', name)
+        branch2 = bizarro.repo.start_branch(self.clone2, 'master', name)
+        
+        #
+        # Make a new files in each branch and save them.
+        #
+        branch1.checkout()
+        branch2.checkout()
+        
+        repo_path1, real_path1 = bizarro.repo.make_working_file(self.clone1, '', 'file1.md')
+        repo_path2, real_path2 = bizarro.repo.make_working_file(self.clone2, '', 'file2.md')
+        
+        with open(real_path1, 'w') as file:
+            jekyll.dump_jekyll_doc(dict(title='Hello'), 'Hello hello.', file)
+        
+        with open(real_path2, 'w') as file:
+            jekyll.dump_jekyll_doc(dict(title='Goodbye'), 'Goodbye goodbye.', file)
+        
+        #
+        # Show that the changes from the first branch made it to origin.
+        #
+        args1 = self.clone1, 'file1.md', 'Saving', branch1.commit.hexsha
+        commit1 = bizarro.repo.save_working_file(*args1)
+
+        self.assertEquals(self.origin.branches[name].commit, commit1)
+        self.assertEquals(commit1, branch1.commit)
+        
+        #
+        # Show that the changes from the second branch also made it to origin.
+        #
+        args2 = self.clone2, 'file2.md', 'Saving', branch2.commit.hexsha
+        commit2 = bizarro.repo.save_working_file(*args2)
+
+        self.assertEquals(self.origin.branches[name].commit, commit2)
+        self.assertEquals(commit2, branch2.commit)
+        
+        #
+        # Show that the merge from the second branch made it back to the first. 
+        #
+        branch1b = bizarro.repo.start_branch(self.clone1, 'master', name)
+
+        self.assertEquals(branch1b.commit, branch2.commit)
+    
+    def test_simple_conflict(self):
+        ''' Test that a conflict in two branches appears at the right spot.
+        '''
+        name = str(uuid4())
+        branch1 = bizarro.repo.start_branch(self.clone1, 'master', name)
+        branch2 = bizarro.repo.start_branch(self.clone2, 'master', name)
+        
+        #
+        # Make a new files in each branch and save them.
+        #
+        branch1.checkout()
+        branch2.checkout()
+        
+        repo_path1, real_path1 = bizarro.repo.make_working_file(self.clone1, '', 'conflict.md')
+        repo_path2, real_path2 = bizarro.repo.make_working_file(self.clone2, '', 'conflict.md')
+        
+        with open(real_path1, 'w') as file:
+            jekyll.dump_jekyll_doc(dict(title='Hello'), 'Hello hello.', file)
+        
+        with open(real_path2, 'w') as file:
+            jekyll.dump_jekyll_doc(dict(title='Goodbye'), 'Goodbye goodbye.', file)
+        
+        #
+        # Show that the changes from the first branch made it to origin.
+        #
+        args1 = self.clone1, 'conflict.md', 'Saving', branch1.commit.hexsha
+        commit1 = bizarro.repo.save_working_file(*args1)
+
+        self.assertEquals(self.origin.branches[name].commit, commit1)
+        self.assertEquals(commit1, branch1.commit)
+        
+        #
+        # Show that the changes from the second branch conflict with the first.
+        #
+        with self.assertRaises(bizarro.repo.MergeConflict):
+            args2 = self.clone2, 'conflict.md', 'Saving', branch2.commit.hexsha
+            commit2 = bizarro.repo.save_working_file(*args2)
+    
     def tearDown(self):
         rmtree(self.origin.git_dir)
         rmtree(self.clone1.working_dir)