=== Problem ===
I upgraded from Mercurial 3.5.2 to 3.6.1 and have noticed that `arc land` will regularly fail with:
```
abort: default repository not configured!
```
arcanist 172c930630a960ea79ada1dbeb50f2ad561d3870 (4 Oct 2015)
libphutil dbf792a053fca78fb55b5ed193bb203c7f9049cb (8 Oct 2015)
---
=== Workaround ===
1. `arc land --hold`
2. `hg book -r tip master`
- //Note that this makes the assumption that `tip` will point to the last rebased/squashed change. This was the case in my situation but may not be in yours. Make sure to move the `master` bookmark to the correct changeset just landed locally to go upstream. Typically this is just moving the `master` bookmark forward one changeset assuming `immutable.history=false`.//
3. `hg push -r master`
---
=== Bug Hunt ===
It looks like the execution of this command causes the failure:
```
hg push -r 'master' ''
```
Removing the two quotes at the end fixes this. Here's where the command appears to be created from:
https://secure.phabricator.com/diffusion/ARC/browse/master/src/workflow/ArcanistLandWorkflow.php;e3e232530c6e9393228cdd246ba9f4a48c0f5917$1285
I took a browse through the Mercurial release notes and found these a little suspish:
|Description|Bug|Change|
|---|---|---|
|ui: change default path fallback mechanism|http://bz.mercurial-scm.org/show_bug.cgi?id=4796|https://selenic.com/repo/hg/rev/663fbc336e22|
|revsets: makes follow() supports file patterns|http://bz.mercurial-scm.org/show_bug.cgi?id=4757|https://selenic.com/repo/hg/rev/5618858dce26|
|revset: do not fall through to revspec for literal: branch |http://bz.mercurial-scm.org/show_bug.cgi?id=4838|https://selenic.com/repo/hg/rev/832feae7c986|
Not sure whether this would be considered a bug in mercurial or not.
---
=== Error Details ===
```lang=console,name=arc land,lines=12,counterexample
cspeck@host128 ~/S/e/mimjava> arc land arcpatch-D1293
Updating master...
The following commit(s) will be landed:
68cad22aec88 Task #56697 - Backported Task #55772 (D1133), with some minor adjustments.
Switched to bookmark arcpatch-D1293. Identifying and merging...
Landing revision 'D1293: Task #56697 - Backported Task #55772 (D1133), with some minor adjustments.'...
BUILDS PASSED Harbormaster builds for the active diff completed successfully.
rebasing 93808:68cad22aec88 "Task #56697 - Backported Task #55772 (D1133), with some minor adjustments." (arcpatch-D1293)
Checking for foot shooting...
Legit-type commit for #56697
saved backup bundle to /Users/cspeck/Source/enad/mimjava/.hg/strip-backup/68cad22aec88-0acbfe9c-backup.hg
rebasing 93809:9d00d6257a10 "Task #56697 - Backported Task #55772 (D1133), with some minor adjustments." (tip arcpatch-D1293)
Checking for foot shooting...
Legit-type commit for #56697
Pushing change...
abort: default repository not configured!
(see the "path" section in "hg help config")
PUSH FAILED!
Switched back to bookmark arcpatch-D1293.
Usage Exception: 'hg push' failed! Fix the error and push this change manually.
```
```lang=console,name=arc land --trace,lines=12,counterexample
cspeck@host128 ~/S/e/mimjava> arc land arcpatch-D1293 --trace
libphutil loaded from '/Users/cspeck/Projects/phacility/libphutil/src'.
arcanist loaded from '/Users/cspeck/Projects/phacility/arcanist/src'.
Config: Reading user configuration file "/Users/cspeck/.arcrc"...
Config: Did not find system configuration at "/etc/arcconfig".
Working Copy: Reading .arcconfig from "/Users/cspeck/Source/enad/mimjava/.arcconfig".
Working Copy: Path "/Users/cspeck/Source/enad/mimjava" is part of `hg` working copy "/Users/cspeck/Source/enad/mimjava".
Working Copy: Project root is at "/Users/cspeck/Source/enad/mimjava".
Config: Did not find local configuration at "/Users/cspeck/Source/enad/mimjava/.hg/arc/config".
>>> [0] <conduit> user.whoami() <bytes = 117>
>>> [1] <http> https://phab.company.com/api/user.whoami
<<< [1] <http> 454,103 us
<<< [0] <conduit> 456,646 us
>>> [2] <exec> $ HGPLAIN=1 hg bookmarks
<<< [2] <exec> 95,399 us
>>> [3] <exec> $ HGPLAIN=1 hg bookmarks
<<< [3] <exec> 97,234 us
>>> [4] <exec> $ HGPLAIN=1 hg bookmarks
<<< [4] <exec> 92,537 us
>>> [5] <exec> $ HGPLAIN=1 hg help rebase
<<< [5] <exec> 104,614 us
>>> [6] <exec> $ HGPLAIN=1 hg status
<<< [6] <exec> 406,822 us
Updating master...
>>> [7] <exec> $ HGPLAIN=1 hg pull
<<< [7] <exec> 931,432 us
>>> [8] <exec> $ HGPLAIN=1 hg branch
<<< [8] <exec> 85,302 us
>>> [9] <exec> $ HGPLAIN=1 hg help phase
<<< [9] <exec> 93,585 us
>>> [10] <exec> $ HGPLAIN=1 hg log -r 'master' --template '{phase}'
<<< [10] <exec> 100,496 us
>>> [11] <exec> $ HGPLAIN=1 hg log -l 1 --template '{node}' -r 'ancestor('\''master'\'','\''arcpatch-D1293'\'')' --
<<< [11] <exec> 111,591 us
>>> [12] <exec> $ HGPLAIN=1 hg log -r 'reverse(('\''a3dea2998c46066a6d9bd7bf991c22d788a9f455'\''::'\''arcpatch-D1293'\'') - '\''a3dea2998c46066a6d9bd7bf991c22d788a9f455'\'')' --template '{node|short} {desc|firstline}\n'
<<< [12] <exec> 110,302 us
The following commit(s) will be landed:
9d00d6257a10 Task #56697 - Backported Task #55772 (D1133), with some minor adjustments.
>>> [13] <exec> $ HGPLAIN=1 hg bookmarks
<<< [13] <exec> 94,175 us
Switched to bookmark arcpatch-D1293. Identifying and merging...
>>> [14] <exec> $ HGPLAIN=1 hg log -l 1 --template '{node}' -r 'ancestor('\''master'\'',.)' --
<<< [14] <exec> 109,110 us
>>> [15] <exec> $ HGPLAIN=1 hg log --template '{node}{desc}' --rev '('\''a3dea2998c46066a6d9bd7bf991c22d788a9f455'\''::. - '\''a3dea2998c46066a6d9bd7bf991c22d788a9f455'\'')' --branch 'default' --
<<< [15] <exec> 112,930 us
>>> [16] <conduit> differential.query() <bytes = 142>
>>> [17] <http> https://phab.company.com/api/differential.query
<<< [17] <http> 452,049 us
<<< [16] <conduit> 452,255 us
>>> [18] <conduit> differential.getcommitmessage() <bytes = 150>
>>> [19] <http> https://phab.company.com/api/differential.getcommitmessage
<<< [19] <http> 222,144 us
<<< [18] <conduit> 222,329 us
Landing revision 'D1293: Task #56697 - Backported Task #55772 (D1133), with some minor adjustments.'...
>>> [20] <conduit> harbormaster.querybuildables() <bytes = 218>
>>> [21] <http> https://phab.company.com/api/harbormaster.querybuildables
<<< [21] <http> 202,702 us
<<< [20] <conduit> 202,893 us
BUILDS PASSED Harbormaster builds for the active diff completed successfully.
>>> [22] <exec> $ HGPLAIN=1 hg log -l 1 --template '{node}' -r 'master' --
<<< [22] <exec> 98,390 us
>>> [23] <exec> $ HGPLAIN=1 hg log -l 1 --template '{node}' -r 'ancestor('\''master'\'', '\''arcpatch-D1293'\'')' --
<<< [23] <exec> 107,116 us
>>> [24] <exec> $ HGPLAIN=1 hg log -l 1 --template '{node}' -r 'arcpatch-D1293' --
<<< [24] <exec> 99,346 us
>>> [25] <exec> $ HGPLAIN=1 hg log -l 1 --template '{node}' -r 'first(('\''master'\''::'\''arcpatch-D1293'\'')-'\''master'\'')' --
<<< [25] <exec> 106,430 us
>>> [26] <exec> $ HGPLAIN=1 hg log --template '{node}\n' -r 'roots(descendants('\''9d00d6257a10d6618e554b49d1a43a5769e8ece6'\'')-descendants('\''arcpatch-D1293'\'')-('\''9d00d6257a10d6618e554b49d1a43a5769e8ece6'\''::'\''arcpatch-D1293'\''))'
<<< [26] <exec> 106,381 us
>>> [27] <exec> $ HGPLAIN=1 hg rebase --collapse --keep --logfile '/private/var/folders/kw/22j3hs0j08v7lr6j448pm8lw0000gp/T/9t3v5stozdwkcs0g/94650-kNA3S8' -r '('\''9d00d6257a10d6618e554b49d1a43a5769e8ece6'\''::'\''arcpatch-D1293'\'')' -d 'master'
rebasing 93809:9d00d6257a10 "Task #56697 - Backported Task #55772 (D1133), with some minor adjustments." (tip arcpatch-D1293)
Checking for foot shooting...
Legit-type commit for #56697
<<< [27] <exec> 1,175,219 us
>>> [28] <exec> $ HGPLAIN=1 hg bookmarks
<<< [28] <exec> 96,307 us
>>> [29] <exec> $ HGPLAIN=1 hg bookmark -f 'master'
<<< [29] <exec> 108,289 us
>>> [30] <exec> $ HGPLAIN=1 hg bookmark -f 'arcpatch-D1293' -r '9d00d6257a10d6618e554b49d1a43a5769e8ece6'
<<< [30] <exec> 106,173 us
>>> [31] <exec> $ HGPLAIN=1 hg log -r 'children('\''arcpatch-D1293'\'')' --template '{node}\n'
<<< [31] <exec> 125,097 us
>>> [32] <exec> $ HGPLAIN=1 hg checkout 'master'
<<< [32] <exec> 352,403 us
>>> [33] <event> land.willPushRevision <listeners = 0>
<<< [33] <event> 61 us
Pushing change...
>>> [34] <exec> $ HGPLAIN=1 hg push -r 'master' ''
abort: default repository not configured!
(see the "path" section in "hg help config")
<<< [34] <exec> 89,715 us
PUSH FAILED!
>>> [35] <exec> $ HGPLAIN=1 hg --config extensions.mq= strip 'master'
<<< [35] <exec> 764,256 us
>>> [36] <exec> $ HGPLAIN=1 hg checkout 'arcpatch-D1293'
<<< [36] <exec> 545,349 us
Switched back to bookmark arcpatch-D1293.
Usage Exception: 'hg push' failed! Fix the error and push this change manually.
[2015-11-17 21:50:25] EXCEPTION: (ArcanistUsageException) 'hg push' failed! Fix the error and push this change manually. at [<arcanist>/src/workflow/ArcanistLandWorkflow.php:1083]
arcanist(head=master, ref.master=172c930630a9), phutil(head=master, ref.master=dbf792a053fc)
#0 ArcanistLandWorkflow::push() called at [<arcanist>/src/workflow/ArcanistLandWorkflow.php:224]
#1 ArcanistLandWorkflow::run() called at [<arcanist>/scripts/arcanist.php:382]
```