topic: check that repo.currenttopic is set before using it as an argument
repo.currenttopic can be an empty string, which means there's no current topic
set. This fact can be used to short-circuit some checks.
Also, this avoids passing an empty string as an argument to topic() revset.
$ cat >> $HGRCPATH <<EOF
> [defaults]
> amend=-d "0 0"
> [web]
> push_ssl = false
> allow_push = *
> [phases]
> publish = False
> [alias]
> qlog = log --template='{rev} - {node|short} {desc} ({phase})\n'
> [diff]
> git = 1
> unified = 0
> [extensions]
> EOF
$ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
$ mkcommit() {
> echo "$1" >> "$1"
> hg add "$1"
> hg ci -m "add $1"
> }
$ hg init local
$ hg init other
$ cd local
$ touch 1 2 3 4 5 6 7 8 9 0
$ hg add 1 2 3 4 5 6 7 8 9 0
$ mkcommit A
$ mkcommit B
$ mkcommit C
$ hg log -G
@ changeset: 2:829b19580856
| tag: tip
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: add C
|
o changeset: 1:97b8f02ab29e
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: add B
|
o changeset: 0:5d8dabd3961b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add A
$ hg push ../other
pushing to ../other
searching for changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 13 changes to 13 files
$ hg -R ../other verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
13 files, 3 changesets, 13 total revisions
$ mkcommit D
$ mkcommit E
$ hg up -q .^^
$ hg revert -r tip -a -q
$ hg ci -m 'coin' -q
$ hg log -G
@ changeset: 5:8313a6afebbb
| tag: tip
| parent: 2:829b19580856
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: coin
|
| o changeset: 4:076ec8ade1ac
| | user: test
| | date: Thu Jan 01 00:00:00 1970 +0000
| | summary: add E
| |
| o changeset: 3:824d9bb109f6
|/ user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: add D
|
o changeset: 2:829b19580856
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: add C
|
o changeset: 1:97b8f02ab29e
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: add B
|
o changeset: 0:5d8dabd3961b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add A
$ hg prune --fold -n -1 -- -2 -3
2 changesets pruned
$ hg push ../other
pushing to ../other
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 2 changes to 2 files
2 new obsolescence markers
$ hg -R ../other verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
15 files, 4 changesets, 15 total revisions