util: improve util inspect output

[BridgeAR]

Please have a look at the commit messages for details.

@nodejs/util PTAL

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

[nodejs-github-bot]

@BridgeAR Sadly, an error occurred when I tried to trigger a build. :(

[BridgeAR]

I just pushed one small commit that adds one more check to prevent unnecessary work in the default case (but no changed behavior).

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/22039/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/22053/ ✔️

[mcollina]

Can you please explain how this improves the output?

[BridgeAR]

@mcollina did you see the commit messages?

util: improve `inspect()` compact number mode

This fixes a proportion calculation for lots of short array entries
with at least one bigger one that alone makes up for more than one
fifth of all other entries together.

util: improve error property inspection

This makes sure that errors that contain extra properties show those
properties on a separate line.

Without the first commit the corresponding test would just create a single
line for each array entry instead of grouping them together.

Without the second commit the corresponding tests would not add a linebreak
in case an error has extra properties.

const err = new Error();
err.foo = true;
console.log(err);
// Only the last line:

// Before
//     at REPLServer.Interface._line (readline.js:675:8) foo: true }

// Now
//     at REPLServer.Interface._line (readline.js:675:8)
//   foo: true }

[mcollina]

LGTM

[BridgeAR]

Landed in 14b2db0, f7c9685 🎉