Add test for json_decode depth <= zero

[nlubisch]

This test covers json_decode depth parameter error handling.
It tests depth for zero and depth for lower than zero.

This Test was contributed by the PHP Usergroup Münster (phpugms)

[krakjoe]

This probably belongs in ext/json/json_decode_error.phpt

[nlubisch]

So i should append my tests to the file ext/json/tests/json_decode_error.phpt?

I've read here, that the test output should be kept at a maximum of 10 lines. The other test (json_decode_error.phpt) already has 11 lines so i decided it is time to start a new one.

[krakjoe]

Confusing information is confusing ... sorry about that ...

The guidelines make a distinction between tests with 10 lines, and tests with thousands of lines ... at this point, I think it would be sensible to avoid creating additional files for the sake of a few lines of test code when another file with 9 lines already exists ... so long as we don't take it to the extremes that the guidelines are trying to warn you about, I think that's okay ...

[nlubisch]

Thanks for making it clear to me. I moved my test code to json_decode_error.phpt and removed the second one.

[carusogabriel]

We already have tests for that upstream.