[StGit PATCH] Restore the original applied patches during 'commit'

[Catalin Marinas <catalin.marinas@gmail.com>]

If committing a patch in the middle of a series, the resulting stack
doesn't have any patches applied. The trans.pop_patches() function only
returns the additional patches that had to be popped rather than all
popped patches. The patch also adds some tests for the 'commit' command.

Signed-off-by: Catalin Marinas <catalin.marinas@gmail.com>
Reported-by: Jeenu Viswambharan <Jeenu.Viswambharan@arm.com>
Cc: Karl Hasselström <kha@treskal.com>
---
 stgit/commands/commit.py |    8 ++++++--
 t/t1303-commit.sh        |   21 +++++++++++++++++++++
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/stgit/commands/commit.py b/stgit/commands/commit.py
index 7bdd8c6..b21c85f 100644
--- a/stgit/commands/commit.py
+++ b/stgit/commands/commit.py
@@ -87,9 +87,13 @@ def func(parser, options, args):
         for i in xrange(min(len(stack.patchorder.applied), len(patches))):
             if stack.patchorder.applied[i] == patches[i]:
                 common_prefix += 1
+            else:
+                break
         if common_prefix < len(patches):
-            to_push = trans.pop_patches(
-                lambda pn: pn in stack.patchorder.applied[common_prefix:])
+            to_push = [pn for pn in stack.patchorder.applied[common_prefix:]
+                       if pn not in patches[common_prefix:]]
+            # this pops all the applied patches from common_prefix
+            trans.pop_patches(lambda pn: pn in to_push)
             for pn in patches[common_prefix:]:
                 trans.push_patch(pn, iw)
         else:
diff --git a/t/t1303-commit.sh b/t/t1303-commit.sh
index d53b9f2..2d85078 100755
--- a/t/t1303-commit.sh
+++ b/t/t1303-commit.sh
@@ -6,6 +6,27 @@ test_expect_success 'Initialize the StGIT repository' '
     stg init
 '
 
+test_expect_success 'Commit middle patch' '
+    stg new -m p1 &&
+    stg new -m p2 &&
+    stg new -m p3 &&
+    stg new -m p4 &&
+    stg pop &&
+    stg commit p2 &&
+    test "$(echo $(stg series))" = "+ p1 > p3 - p4"
+'
+
+test_expect_success 'Commit first patch' '
+    stg commit &&
+    test "$(echo $(stg series))" = "> p3 - p4"
+'
+
+test_expect_success 'Commit all patches' '
+    stg push &&
+    stg commit -a &&
+    test "$(echo $(stg series))" = ""
+'
+
 # stg commit with top != head should not succeed, since the committed
 # patches are poptentially lost.
 test_expect_success 'Commit when top != head (should fail)' '