[SPARK-20661][SPARKR][TEST][FOLLOWUP] SparkR tableNames() test fails

[felixcheung]

What changes were proposed in this pull request?

Change it to check for relative count like in this test https://github.com/apache/spark/blame/master/R/pkg/inst/tests/testthat/test_sparkSQL.R#L3355 for catalog APIs

How was this patch tested?

unit tests, this needs to combine with another commit with SQL change to check

[falaki]

@felixcheung this approach is fine, but I think it is better if unit tests do not leave any side-effects to begin with. In this case every test should clean up state before and after (similar to beforeAach())

[felixcheung]

that I agree completely, @falaki - looks like tests fail apparently when running Scala tests before running R tests

[felixcheung]

I think this might be the reason? @yhuai @gatorsmile @ueshin
Am I reading these right that these tables are created but never dropped?
2269155#diff-1e55698cc579cbae676f827a89c2dc2eR186

[yhuai]

@felixcheung you are right. That is the problem.

[yhuai]

@falaki's PR did not actually trigger that test.

[yhuai]

lgtm

[felixcheung]

hmm, spoke too soon I think - looks to me like all the withTable clause are in place and complete.
not sure what can be leaking through then..

[yhuai]

i see. I think d4c1a9d is good. How about we get it checked in first (after jenkins passes)?

[felixcheung]

right. I think it's a good way to decouple R tests from any earlier states and also not to mask the error/leak. I'll get that in when Jenkins pass (and see if I could figure out what is leaked)

[gatorsmile]

How about #17908? It tries to reset the cataloged metadata objects and temporary objects.

[SparkQA]

Test build #76612 has finished for PR 17905 at commit 1aa17d8.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[felixcheung]

ok Jenkins passes, I'm going to merge this in since there are a bunch of PR failing because of this, even when they say it's up-to-date with master.
I'm going to investigate further though.

[felixcheung]

merged to master/2.2

[SparkQA]

Test build #76634 has started for PR 17905 at commit b37a760.

[AmplabJenkins]

Test FAILed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder/76634/
Test FAILed.