* Check for duplicate label names in remote read
Also add test to confirm that #5731 is fixed
* Use subtests in TestValidateLabelsAndMetricName
* Really check that expectedErr matches err
Signed-off-by: Vadym Martsynovskyy <vmartsynovskyy@gmail.com>
The labelsets returned from remote read are mutated in higher levels
(like seriesFilter.Labels()) and since the concreteSeriesSet didn't
return a copy, the external mutation affected the labelset in the
concreteSeries itself. This resulted in bizarre bugs where local and
remote series would show with identical label sets in the UI, but not be
deduplicated, since internally, a series might come to look like:
{__name__="node_load5", instance="192.168.1.202:12090", job="node_exporter", node="odroid", node="odroid"}
(note the repetition of the last label)
Chris Marchbanks
Vadym Martsynovskyy
Matt Layher
Tom Wilkie
Julius Volz
Tom Wilkie