Optimise the merge operation

The merge operation performs unnecessary git-checkout-cache which was
already done by git-read-tree or gitmergeonefile.py. The refresh
resulted from a push operation should not check for the tree status
since the index is already up-to-date a successful merge. For an failed
merge, the commit is not performed anyway.

Signed-off-by: Catalin Marinas <catalin.marinas@gmail.com>

diff --git a/stgit/commands/common.py b/stgit/commands/common.py
index c4ddc94..86f62fb 100644 (file)
--- a/stgit/commands/common.py
+++ b/stgit/commands/common.py
@@ -100,7 +100,7 @@ def print_crt_patch():
         print 'No patches applied'
 
 def resolved(filename):
-    git.update_cache([filename])
+    git.update_cache([filename], force = True)
     for ext in ['.local', '.older', '.remote']:
         fn = filename + ext
         if os.path.isfile(fn):

diff --git a/stgit/git.py b/stgit/git.py
index ae29eb8..fb75a85 100644 (file)
--- a/stgit/git.py
+++ b/stgit/git.py
@@ -254,41 +254,45 @@ def rm(files, force = False):
         if files:
             __run('git-update-cache --force-remove --', files)
 
-def update_cache(files):
+def update_cache(files = [], force = False):
     """Update the cache information for the given files
     """
-    files_here = []
-    files_gone = []
+    cache_files = __tree_status(files)
 
-    for f in files:
-        if os.path.exists(f):
-            files_here.append(f)
-        else:
-            files_gone.append(f)
+    # everything is up-to-date
+    if len(cache_files) == 0:
+        return False
+
+    # check for unresolved conflicts
+    if not force and [x for x in cache_files
+                      if x[0] not in ['M', 'N', 'A', 'D']]:
+        raise GitException, 'Updating cache failed: unresolved conflicts'
 
-    if files_here:
-        __run('git-update-cache --', files_here)
-    if files_gone:
-        __run('git-update-cache --remove --', files_gone)
+    # update the cache
+    add_files = [x[1] for x in cache_files if x[0] in ['N', 'A']]
+    rm_files =  [x[1] for x in cache_files if x[0] in ['D']]
+    m_files =   [x[1] for x in cache_files if x[0] in ['M']]
+
+    if add_files and __run('git-update-cache --add --', add_files) != 0:
+        raise GitException, 'Failed git-update-cache --add'
+    if rm_files and __run('git-update-cache --force-remove --', rm_files) != 0:
+        raise GitException, 'Failed git-update-cache --rm'
+    if m_files and __run('git-update-cache --', m_files) != 0:
+        raise GitException, 'Failed git-update-cache'
+
+    return True
 
 def commit(message, files = [], parents = [], allowempty = False,
+           cache_update = True,
            author_name = None, author_email = None, author_date = None,
            committer_name = None, committer_email = None):
     """Commit the current tree to repository
     """
-    first = (parents == [])
-
     # Get the tree status
-    if not first:
-        cache_files = __tree_status(files)
-
-    if not first and len(cache_files) == 0 and not allowempty:
-        raise GitException, 'No changes to commit'
-
-    # check for unresolved conflicts
-    if not first and len(filter(lambda x: x[0] not in ['M', 'N', 'A', 'D'],
-                                cache_files)) != 0:
-        raise GitException, 'Commit failed: unresolved conflicts'
+    if cache_update and parents != []:
+        changes = update_cache(files)
+        if not changes and not allowempty:
+            raise GitException, 'No changes to commit'
 
     # get the commit message
     f = file('.commitmsg', 'w+')
@@ -298,29 +302,6 @@ def commit(message, files = [], parents = [], allowempty = False,
         print >> f, message
     f.close()
 
-    # update the cache
-    if not first:
-        add_files=[]
-        rm_files=[]
-        m_files=[]
-        for f in cache_files:
-            if f[0] in ['N', 'A']:
-                add_files.append(f[1])
-            elif f[0] == 'D':
-                rm_files.append(f[1])
-            else:
-                m_files.append(f[1])
-
-    if add_files:
-        if __run('git-update-cache --add --', add_files):
-            raise GitException, 'Failed git-update-cache --add'
-    if rm_files:
-        if __run('git-update-cache --force-remove --', rm_files):
-            raise GitException, 'Failed git-update-cache --rm'
-    if m_files:
-        if __run('git-update-cache --', m_files):
-            raise GitException, 'Failed git-update-cache'
-
     # write the index to repository
     tree_id = _output_one_line('git-write-tree')
 
@@ -361,10 +342,6 @@ def merge(base, head1, head2):
     if os.system('git-merge-cache -o gitmergeonefile.py -a') != 0:
         raise GitException, 'git-merge-cache failed (possible conflicts)'
 
-    # this should not fail
-    if os.system('git-checkout-cache -f -a') != 0:
-        raise GitException, 'Failed git-checkout-cache'
-
 def status(files = [], modified = False, new = False, deleted = False,
            conflict = False, unknown = False):
     """Show the tree status
@@ -385,7 +362,7 @@ def status(files = [], modified = False, new = False, deleted = False,
             filestat.append('C')
         if unknown:
             filestat.append('?')
-        cache_files = filter(lambda x: x[0] in filestat, cache_files)
+        cache_files = [x for x in cache_files if x[0] in filestat]
 
     for fs in cache_files:
         if all:

diff --git a/stgit/stack.py b/stgit/stack.py
index ef7e3f6..46d6ee5 100644 (file)
--- a/stgit/stack.py
+++ b/stgit/stack.py
@@ -326,7 +326,7 @@ class Series:
         create_empty_file(self.__unapplied_file)
         self.__begin_stack_check()
 
-    def refresh_patch(self, message = None, edit = False,
+    def refresh_patch(self, message = None, edit = False, cache_update = True,
                       author_name = None, author_email = None,
                       author_date = None,
                       committer_name = None, committer_email = None,
@@ -363,6 +363,7 @@ class Series:
             committer_email = patch.get_commemail()
 
         commit_id = git.commit(message = descr, parents = [patch.get_bottom()],
+                               cache_update = cache_update,
                                allowempty = True,
                                author_name = author_name,
                                author_email = author_email,
@@ -485,7 +486,8 @@ class Series:
         if head != bottom:
             if not ex:
                 # if the merge was OK and no conflicts, just refresh the patch
-                self.refresh_patch()
+                # The GIT cache was already updated by the merge operation
+                self.refresh_patch(cache_update = False)
             else:
                 raise StackException, str(ex)