patch, 6 partsMake sure that we only uncommit commits with exactly one parent

stgit/main.py, stgit/utils.py

diff --git a/stgit/main.py b/stgit/main.py
index 79044b0..663fdec 100644
--- a/stgit/main.py
+++ b/stgit/main.py
@@ -18,7 +18,7 @@ along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 """
 
-import sys, os
+import sys, os, traceback
 from optparse import OptionParser
 
 import stgit.commands
@@ -279,10 +279,13 @@ def main():
     except (StgException, IOError, ParsingError, NoSectionError), err:
         out.error(str(err), title = '%s %s' % (prog, cmd))
         if debug_level > 0:
-            raise
-        else:
-            sys.exit(utils.STGIT_COMMAND_ERROR)
+            traceback.print_exc()
+        sys.exit(utils.STGIT_COMMAND_ERROR)
     except KeyboardInterrupt:
         sys.exit(utils.STGIT_GENERAL_ERROR)
+    except:
+        out.error('Unhandled exception:')
+        traceback.print_exc()
+        sys.exit(utils.STGIT_BUG_ERROR)
 
     sys.exit(ret or utils.STGIT_SUCCESS)
diff --git a/stgit/utils.py b/stgit/utils.py
index b75c3b4..cd52382 100644
--- a/stgit/utils.py
+++ b/stgit/utils.py
@@ -327,6 +327,7 @@ STGIT_SUCCESS = 0        # everything's OK
 STGIT_GENERAL_ERROR = 1  # seems to be non-command-specific error
 STGIT_COMMAND_ERROR = 2  # seems to be a command that failed
 STGIT_CONFLICT = 3       # merge conflict, otherwise OK
+STGIT_BUG_ERROR = 4      # a bug in StGit
 
 def strip_leading(prefix, s):
     """Strip leading prefix from a string. Blow up if the prefix isn't

diff --git a/stgit/lib/git.py b/stgit/lib/git.py
index 50dc4f1..cdfe885 100644
--- a/stgit/lib/git.py
+++ b/stgit/lib/git.py
@@ -204,7 +204,7 @@ class Commitdata(Repr):
                 ) % (tree, parents, self.author, self.committer, self.message)
     @classmethod
     def parse(cls, repository, s):
-        cd = cls()
+        cd = cls(parents = [])
         lines = list(s.splitlines(True))
         for i in xrange(len(lines)):
             line = lines[i].strip()

diff --git a/t/t1300-uncommit.sh b/t/t1300-uncommit.sh
index d86e579..0d952a7 100755
--- a/t/t1300-uncommit.sh
+++ b/t/t1300-uncommit.sh
@@ -78,4 +78,9 @@ test_expect_success \
     stg commit --all
 '
 
+test_expect_failure 'Uncommit a commit with not precisely one parent' '
+    stg uncommit -n 5 ; [ $? = 2 ] &&
+    [ "$(echo $(stg series))" = "" ]
+'
+
 test_done

stgit/commands/uncommit.py, t/t1300-uncommit.sh

diff --git a/stgit/commands/uncommit.py b/stgit/commands/uncommit.py
index 933ec60..272c5db 100644
--- a/stgit/commands/uncommit.py
+++ b/stgit/commands/uncommit.py
@@ -85,13 +85,23 @@ def func(parser, options, args):
         patchnames = args
         patch_nr = len(patchnames)
 
+    def get_parent(c):
+        next = c.data.parents
+        try:
+            [next] = next
+        except ValueError:
+            raise common.CmdException(
+                'Trying to uncommit %s, which does not have exactly one parent'
+                % c.sha1)
+        return next
+
     commits = []
     next_commit = stack.base
     if patch_nr:
         out.start('Uncommitting %d patches' % patch_nr)
         for i in xrange(patch_nr):
             commits.append(next_commit)
-            next_commit = next_commit.data.parent
+            next_commit = get_parent(next_commit)
     else:
         if options.exclusive:
             out.start('Uncommitting to %s (exclusive)' % to_commit)
@@ -103,7 +113,7 @@ def func(parser, options, args):
                     commits.append(next_commit)
                 break
             commits.append(next_commit)
-            next_commit = next_commit.data.parent
+            next_commit = get_parent(next_commit)
         patch_nr = len(commits)
 
     taken_names = set(stack.patchorder.applied + stack.patchorder.unapplied)
diff --git a/t/t1300-uncommit.sh b/t/t1300-uncommit.sh
index 0d952a7..a906d13 100755
--- a/t/t1300-uncommit.sh
+++ b/t/t1300-uncommit.sh
@@ -78,7 +78,7 @@ test_expect_success \
     stg commit --all
 '
 
-test_expect_failure 'Uncommit a commit with not precisely one parent' '
+test_expect_success 'Uncommit a commit with not precisely one parent' '
     stg uncommit -n 5 ; [ $? = 2 ] &&
     [ "$(echo $(stg series))" = "" ]
 '

diff --git a/t/t3000-dirty-merge.sh b/t/t3000-dirty-merge.sh
new file mode 100755
index 0000000..dd81c9e
--- /dev/null
+++ b/t/t3000-dirty-merge.sh
@@ -0,0 +1,35 @@
+#!/bin/sh
+
+test_description='Try a push that requires merging a file that is dirty'
+
+. ./test-lib.sh
+
+test_expect_success 'Initialize StGit stack with two patches' '
+    stg init &&
+    touch a &&
+    git add a &&
+    git commit -m a &&
+    echo 1 > a &&
+    git commit -a -m p1 &&
+    echo 2 > a &&
+    git commit -a -m p2 &&
+    stg uncommit -n 2
+'
+
+test_expect_success 'Pop one patch and update the other' '
+    stg goto p1 &&
+    echo 3 > a &&
+    stg refresh
+'
+
+test_expect_failure 'Push with dirty worktree' '
+    echo 4 > a &&
+    [ "$(echo $(stg applied))" = "p1" ] &&
+    [ "$(echo $(stg unapplied))" = "p2" ] &&
+    ! stg goto p2 &&
+    [ "$(echo $(stg applied))" = "p1" ] &&
+    [ "$(echo $(stg unapplied))" = "p2" ] &&
+    [ "$(echo $(cat a))" = "4" ]
+'
+
+test_done

stgit/lib/git.py, stgit/lib/transaction.py, t/t3000-dirty-merge.sh

diff --git a/stgit/lib/git.py b/stgit/lib/git.py
index cdfe885..35b9bbf 100644
--- a/stgit/lib/git.py
+++ b/stgit/lib/git.py
@@ -433,6 +433,9 @@ class Repository(RunWithEnv):
 class MergeException(exception.StgException):
     pass
 
+class MergeConflictException(MergeException):
+    pass
+
 class Index(RunWithEnv):
     def __init__(self, repository, filename):
         self.__repository = repository
@@ -517,14 +520,18 @@ class IndexAndWorktree(RunWithEnv):
         assert isinstance(ours, Tree)
         assert isinstance(theirs, Tree)
         try:
-            self.run(['git', 'merge-recursive', base.sha1, '--', ours.sha1,
-                      theirs.sha1],
-                     env = { 'GITHEAD_%s' % base.sha1: 'ancestor',
-                             'GITHEAD_%s' % ours.sha1: 'current',
-                             'GITHEAD_%s' % theirs.sha1: 'patched'}
-                     ).cwd(self.__worktree.directory).discard_output()
+            r = self.run(['git', 'merge-recursive', base.sha1, '--', ours.sha1,
+                          theirs.sha1],
+                         env = { 'GITHEAD_%s' % base.sha1: 'ancestor',
+                                 'GITHEAD_%s' % ours.sha1: 'current',
+                                 'GITHEAD_%s' % theirs.sha1: 'patched'}
+                         ).cwd(self.__worktree.directory)
+            r.discard_output()
         except run.RunException, e:
-            raise MergeException('Index/worktree dirty')
+            if r.exitcode == 1:
+                raise MergeConflictException()
+            else:
+                raise MergeException('Index/worktree dirty')
     def changed_files(self):
         return self.run(['git', 'diff-files', '--name-only']).output_lines()
     def update_index(self, files):
diff --git a/stgit/lib/transaction.py b/stgit/lib/transaction.py
index 3613b15..2946a67 100644
--- a/stgit/lib/transaction.py
+++ b/stgit/lib/transaction.py
@@ -197,10 +197,12 @@ class StackTransaction(object):
                 tree = iw.index.write_tree()
                 self.__current_tree = tree
                 s = ' (modified)'
-            except git.MergeException:
+            except git.MergeConflictException:
                 tree = ours
                 merge_conflict = True
                 s = ' (conflict)'
+            except git.MergeException, e:
+                self.__halt(str(e))
         cd = cd.set_tree(tree)
         self.patches[pn] = self.__stack.repository.commit(cd)
         del self.unapplied[self.unapplied.index(pn)]
diff --git a/t/t3000-dirty-merge.sh b/t/t3000-dirty-merge.sh
index dd81c9e..d87bba1 100755
--- a/t/t3000-dirty-merge.sh
+++ b/t/t3000-dirty-merge.sh
@@ -22,7 +22,7 @@ test_expect_success 'Pop one patch and update the other' '
     stg refresh
 '
 
-test_expect_failure 'Push with dirty worktree' '
+test_expect_success 'Push with dirty worktree' '
     echo 4 > a &&
     [ "$(echo $(stg applied))" = "p1" ] &&
     [ "$(echo $(stg unapplied))" = "p2" ] &&