[Yum-devel] [PATCH 2/2] Change "history info" to display the last transaction, even aborted ones.

[James Antill]

 Let undo/redo refer to the last transaction, without the user having
to look it up manually.
---
 docs/yum.8 |    7 +++++--
 output.py  |   31 ++++++++++++++++++++++++-------
 2 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/docs/yum.8 b/docs/yum.8
index ddb44a8..c65fcaa 100644
--- a/docs/yum.8
+++ b/docs/yum.8
@@ -246,10 +246,13 @@ transactions (assuming the history_record config. option is set). You can use
 info/list/summary to view what happened, undo/redo to act on that information
 and new to start a new history file.
 
-The info/list/summary commands take either a transactions id or a package (with
+The info/list/summary commands take either a transaction id or a package (with
 wildcards, as in \fBSpecifying package names\fP), all three can also be passed
 no arguments. list can be passed the keyword "all" to list all the transactions.
-undo/redo just take a transaction id.
+
+The undo/redo commands take either a transaction id or the keyword last and
+an offset from the last transaction (Eg. if you've done 250 transactions,
+"last" refers to transaction 250, and "last-4" refers to transaction 246).
 
 In "history list" output the Altered column also gives some extra information
 if there was something not good with the transaction.
diff --git a/output.py b/output.py
index 89c8f91..4102a51 100755
--- a/output.py
+++ b/output.py
@@ -1297,12 +1297,29 @@ to exit.
             return None
 
         tids = []
-        try:
-            int(extcmds[1])
-            tids.append(extcmds[1])
-        except ValueError:
-            self.logger.critical(_('Bad transaction ID given'))
-            return None
+        last = None
+        for extcmd in extcmds[1:]:
+            try:
+                if extcmd == 'last' or extcmd.startswith('last-'):
+                    if last is None:
+                        last = self.history.last(False)
+                        if last is None:
+                            int("z")
+                    tid = last.tid
+                    if extcmd.startswith('last-'):
+                        off = int(extcmd[len('last-'):])
+                        if off <= 0:
+                            int("z")
+                        tid -= off
+                    tids.append(str(tid))
+                    continue
+
+                if int(extcmd) <= 0:
+                    int("z")
+                tids.append(extcmd)
+            except ValueError:
+                self.logger.critical(_('Bad transaction ID given'))
+                return None
 
         old = self.history.old(tids)
         if not old:
@@ -1330,7 +1347,7 @@ to exit.
             tids.update(self.history.search(pats))
 
         if not tids and len(extcmds) < 2:
-            old = self.history.last()
+            old = self.history.last(False)
             if old is not None:
                 tids.add(old.tid)
 
-- 
1.6.5.2