use g++-4.8 (support C++11) and start testing against Node.js version 4.0 on Travis CI

[Mithgol]

This pull request adds Node.js version 4.0 testing.

I've noticed that the tests fail on io.js and Node 4.0.

There are two separate problems here.

The first problem is that the iconv package (needed for testing) won't build.

I've thought (initially) that these engine versions need a newer toolchain environment setting (CXX=g++-4.8) as implied by travis-ci/travis-ci#4771 and netiam/experiments@b700b51, but the actual problem seems to be something else.

The second problem is that the iconv-lite's behaviour is itself not quite right.

I have performed some manual testing on Windows in Node.js v4.0.0, and the results don't seem correct:

The Pile of Poo Test™ seems to fail.

The results of such test were good enough in Node.js v0.12.x and v0.10.x where the result of Buffer('\uD83D\uDCA9', 'cp866').toString('cp866') was '??' (i.e. one question mark for each half of the surrogate pair).

[Mithgol]

The first of the above problems seems to be a problem of iconv and, as such, there it should be dealt with. (bnoordhuis/node-iconv#132)

[bnoordhuis]

See my comment here: the problem is with the default C++ compiler, it's too old to understand C++11.

[Mithgol]

Thanks, the first problem is gone.

Travis CI job logs for iojs and Node.js v4.0.0 now seem to indicate that iconv-lite can no longer extend Node's native set of encodings correctly.

[dougwilson]

It also looks like Node.js 4.0 can no longer natively decode CESU-8.

[bnoordhuis]

Yes, that was removed in nodejs/node@70d1f32 ("deps: update v8 to 4.4.63.9"):

Notable backwards incompatible changes are the removal of the smalloc module and dropped support for CESU-8 decoding. CESU-8 support can be brought back if necessary by doing UTF-8 decoding ourselves.

Long story short: V8 string functions no longer accept CESU-8 as input. Node would have to implement its own UTF-8-to-UTF-16 encoder.

[Mithgol]

Created some Buffers:

Their lengths are fine, but their contents seem quite random.

I suspect that the new version of Node's Buffer constructor (introduced by a rename in nodejs/node@1057d11 and developed elsewhere before that) just isn't as extendable as its previous version. I've opened an issue (nodejs/node#2835) about that.

[ashtuchkin]

Thanks @Mithgol! I fixed the CESU-8 and added warnings for extendNodeEncodings. Seems we cannot do anything at the moment with the latter issue.