Loose parser: fixes and ES6

[RReverser]

Done:

• Simplified some tests.
• Made driver to run already existing tests for both loose and normal parser.
• Fixed inconsistencies in loose parser for found errors (in regexes, arrays etc.).
• Added support for ES6 for loose parser with basic tolerance (might need extension in future for more cases).

Not done:

• There are still few ES5 tests that are failing and not sure what is the best way to fix.
• Template literals and tagged template literals from ES6 (not sure what is the best way to share / inject special tokenizer case for them).
• Loose parser will still need own tests in future, but for now we can at least ensure it works for correct simple code with no specific indentation.

[marijnh]

Great work!

Please put additional testing logic in test/driver.js, so that we don't have to duplicate it in test/index.html (the web-based test runner).

My lint tool spotted a bunch of suspicious things:

./acorn_loose.js: Assignment to global variable (793:4)
./acorn_loose.js: Assignment to global variable (810:6)
./acorn_loose.js: Access to global variable inTemplate. (813:4)
./acorn_loose.js: Access to global variable tokVal. (797:28)
./acorn_loose.js: Access to global variable tokStart. (797:53)
./acorn_loose.js: Access to global variable tokEnd. (810:15)
./acorn_loose.js: Access to global variable tokType. (801:10)
./acorn_loose.js: Access to global variable _bquote. (801:22)
./acorn_loose.js: Access to global variable _dollarBraceL. (806:13)
./acorn_loose.js: Access to global variable tokPos.(810:6)
./acorn_loose.js: Access to global variable _braceR. (811:13)
./acorn_loose.js: Unused function parseTemplate (789:11)

I'm also not sure about the tokenizer magic, I expect you understand the problem more completely than I do.

[RReverser]

@marijnh Oh, right, in the beginning I was going to update web-driver too, but forgot until the moment of submitting PR. Will do.

Will check possible problems, thanks.

[RReverser]

@marijnh Ah - linter is right, I copy-pasted parseTemplate function and tried to enhance it, but as I said in PR message, no luck yet, so just committed as-is. Will remove now.

[RReverser]

Pushed support for web-driver:

[RReverser]

Regarding tokenizer magic - it's not that much problem with functionality but rather with understanding what is the best way to share it between acorn and acorn_loose parsers (as you already did with getToken thing).

[marijnh]

I've done some more work to make all tests pass for the loose parser, excluding the ones that use template strings. See attached patch. I've merged this into master.

[RReverser]

@marijnh Thanks! I'll check what I can about template strings, it shouldn't be too hard to implement them.