transaction: always remove empty journal on abort

When transactions without entries were aborted, the journal (of size 0) was not
unlinked, which prevents subsequent operations until hg recover is run on the
repository.

We also make sure the journal is unlinked when committing, even if the provided
hook doesn't do so.

mercurial/transaction.py

@@ -59,8 +59,7 b' class transaction(object):'
 
     def __del__(self):
         if self.journal:
-            if self.entries: self._abort()
-            self.file.close()
+            self._abort()
 
     @active
     def startgroup(self):
@@ -126,7 +125,7 b' class transaction(object):'
         self.entries = []
         if self.after:
             self.after()
-        else:
+        if os.path.isfile(self.journal):
             os.unlink(self.journal)
         self.journal = None
 
@@ -141,7 +140,10 b' class transaction(object):'
         self.count = 0
         self.file.close()
 
-        if not self.entries: return
+        if not self.entries:
+            if self.journal:
+                os.unlink(self.journal)
+            return
 
         self.report(_("transaction abort!\n"))
 

tests/test-journal-exists

@@ -3,6 +3,7 b''
 hg init
 echo a > a
 hg ci -Am0
+hg -q clone . foo
 
 touch .hg/store/journal
 
@@ -10,3 +11,10 b' echo foo > a'
 hg ci -Am0
 
 hg recover
+
+echo % check that zero-size journals are correctly aborted
+hg bundle -qa repo.hg
+chmod -w foo/.hg/store/00changelog.i
+hg -R foo unbundle repo.hg 2>&1 | sed 's/\(abort: Permission denied\).*/\1/'
+if test -f foo/.hg/store/journal; then echo 'journal exists :-('; fi
+exit 0

tests/test-journal-exists.out

@@ -6,3 +6,6 b' checking manifests'
 crosschecking files in changesets and manifests
 checking files
 1 files, 1 changesets, 1 total revisions
+% check that zero-size journals are correctly aborted
+adding changesets
+abort: Permission denied