nics.test.js failing due to double callback

Uncaught AssertionError: idx should be equal to ndone

FROM
fail (assert.js:84:3)
Function.equal (assert.js:104:27)
next (/opt/smartdc/cloudapi/node_modules/vasync/lib/vasync.js:805:14)
/opt/smartdc/cloudapi/test/nics.test.js:617:21
/opt/smartdc/cloudapi/test/common.js:1113:13
/opt/smartdc/cloudapi/node_modules/sdc-clientsok 11 deleteNicTag sdccloudapitest_nics_nictag1
/lib/restifyclient.js:121:20
parseResponse (/opt/smartdc/cloudapi/node_modules/sdc-clients/node_modules/restify-clients/lib/JsonClient.js:105:9)
IncomingMessage.done (/opt/smartdc/cloudapi/node_modules/sdc-clients/node_modules/restify-clients/lib/StringClient.js:237:13)
IncomingMessage.g (events.js:292:16)
emitNone (events.js:91:20)
IncomingMessage.emit (events.js:185:7)
endReadableNT (_stream_readable.js:978:12)
_combinedTickCallback (internal/process/next_tick.js:80:11)
process._tickCallback (internal/process/next_tick.js:104:9)
./runtests: line 114: 79569 Illegal Instruction     (core dumped) PATH=${NODE_INSTALL}/bin:${PATH} ${NODE_INSTALL}/bin/node --abort_on_uncaught_exception ${t}
     79570 Done                    | tee -a ${OUTPUT_DIR}/cloudapi.tap

Read test/nics.test.js around line 617 and test/common.js around line 1113, then reproduce the failure with ./runtests. Done means the nics test no longer reports that idx should equal ndone or fails because of a double callback.