[StGit PATCH 3/3] Make sure that stg uncommit doesn't touch the branch head

["Karl Hasselström" <kha@treskal.com>]

Even if top != head. It used to set head to top; but with this patch,
it doesn't anymore.

Signed-off-by: Karl Hasselström <kha@treskal.com>

---

 stgit/commands/uncommit.py |    2 +-
 stgit/lib/transaction.py   |   19 ++++++++++---------
 t/t1300-uncommit.sh        |    2 +-
 3 files changed, 12 insertions(+), 11 deletions(-)


diff --git a/stgit/commands/uncommit.py b/stgit/commands/uncommit.py
index eb39fcc..9d2dba9 100644
--- a/stgit/commands/uncommit.py
+++ b/stgit/commands/uncommit.py
@@ -136,5 +136,5 @@ def func(parser, options, args):
     for commit, pn in zip(commits, patchnames):
         trans.patches[pn] = commit
     trans.applied = list(reversed(patchnames)) + trans.applied
-    trans.run()
+    trans.run(set_head = False)
     out.done()
diff --git a/stgit/lib/transaction.py b/stgit/lib/transaction.py
index e47997e..23321c7 100644
--- a/stgit/lib/transaction.py
+++ b/stgit/lib/transaction.py
@@ -138,21 +138,22 @@ class StackTransaction(object):
         # The only state we need to restore is index+worktree.
         if iw:
             self.__checkout(self.__stack.head.data.tree, iw)
-    def run(self, iw = None):
+    def run(self, iw = None, set_head = True):
         """Execute the transaction. Will either succeed, or fail (with an
         exception) and do nothing."""
         self.__check_consistency()
         new_head = self.__head
 
         # Set branch head.
-        if iw:
-            try:
-                self.__checkout(new_head.data.tree, iw)
-            except git.CheckoutException:
-                # We have to abort the transaction.
-                self.abort(iw)
-                self.__abort()
-        self.__stack.set_head(new_head, self.__msg)
+        if set_head:
+            if iw:
+                try:
+                    self.__checkout(new_head.data.tree, iw)
+                except git.CheckoutException:
+                    # We have to abort the transaction.
+                    self.abort(iw)
+                    self.__abort()
+            self.__stack.set_head(new_head, self.__msg)
 
         if self.__error:
             out.error(self.__error)
diff --git a/t/t1300-uncommit.sh b/t/t1300-uncommit.sh
index d01eaaa..4a955f6 100755
--- a/t/t1300-uncommit.sh
+++ b/t/t1300-uncommit.sh
@@ -85,7 +85,7 @@ test_expect_success 'Uncommit a commit with not precisely one parent' '
 
 # stg uncommit should work even when top != head, and should not touch
 # the head.
-test_expect_failure 'Uncommit when top != head' '
+test_expect_success 'Uncommit when top != head' '
     stg new -m foo &&
     git reset --hard HEAD^ &&
     h=$(git rev-parse HEAD)