Good point. I am presuming the test suite is comprehensive. Does it cover 100% of all JSON mines? Probably not. But it surfaced about 30 bugs in my own implementation - things I would have never dreamed of.
So it certainly helped me. And just based on how thorough and insane the test suite is, I think I'm in good hands. Not perfect hands - but definitely a million times better than anything I would have come up with on my own.
The test suite made my parser blow up many times, and for each blow up I got to make a conscious decision in my bugfix: how do I want to handle this?
(I decided to let the 10,000 depth nested {{{{{{{{{{{{{{{{{{"key","value"}}}}}}}}}}}}}}}}}}} guy blow up even though it is legal. Yes, I'm too lazy to implement my own stack.) :-)
Doesn’t the test suite’s matrix demonstrate that there are tons of cases that aren’t handled consistently across these parsers?