Sirupsen/logrus — pull request #89 by aybabtme (2014-12-10 02:59:23+00:00)
Title: Fix JSON formatter prefixing old msg/time/level fields

r: @Sirupsen cc: @nickvanw

Wrote a regression test, before fix:

```
cassiopeiae ~/g/s/g/d/c/t/s/g/S/logrus (62b915c...) ➜ go test .
--- FAIL: TestDoubleLoggingDoesntPrefixPreviousFields (0.00s)
Location: logrus_test.go:232
Error:	"map[level:warning msg:omg it is! time:2014-12-09T21:54:19-05:00 fields.level:info fields.msg:looks delicious fields.time:2014-12-09T21:54:19-05:00 context:eating raw fish]" should have 4 item(s), but has 7
Messages:	should only msg/time/level/context fields

Location: logrus_test.go:235
Error:	Expected nil, but got: "looks delicious"
Messages:	should not have prefixed previous `msg` entry

FAIL
FAIL	github.com/Sirupsen/logrus	0.008s
```

after fix:

```
cassiopeiae ~/g/s/g/d/c/t/s/g/S/logrus (36a9dbc...) ➜ go test .
ok	github.com/Sirupsen/logrus	0.008s
```