Add punctuation and comments about code that should not throw.
Also remove a obsolete test and refactor some tests.

PR-URL: https://github.com/nodejs/node/pull/18669
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

There is actually no reason to use `assert.doesNotThrow()` in the
tests. If a test throws, just let the error bubble up right away
instead of first catching it and then rethrowing it.

PR-URL: https://github.com/nodejs/node/pull/18669
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

This was a typo and accidentally returned the wrong value.

Fixes: https://github.com/nodejs/node/issues/14819
Ref: https://github.com/nodejs/node/pull/13467
PR-URL: https://github.com/nodejs/node/pull/14821
Reviewed-By: Evan Lucas <evanlucas@me.com>
Reviewed-By: Yuta Hiroto <hello@about-hiroppy.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>

Add `buffer.constants`, containing length limits for `Buffer` and
`string` instances.

This could be useful for programmers to tell whether a value can
be turned into a string or not.

Ref: https://github.com/nodejs/node/issues/13465
PR-URL: https://github.com/nodejs/node/pull/13467
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>