inspector: fix crash on exception

[seishun]

Fixes #13438.

cc @eugeneo

Checklist

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

Affected core subsystem(s)

inspector

[addaleax]

The “middle” parentheses are unnecessary here

[refack]

Wanted to do this myself 😃

[refack]

Do you have a guarantee that typeof mainScript.endsWith === 'function'?
Maybe try !String.prototype.endsWith(mainScript, '.js')
Also flip if/else and remove !

[seishun]

This is an undocumented internal function. I think it's safe to assume that whoever wants to add a new test will look at the code to figure out how it works (just like I did).

[refack]

Ack.
But I'm still +1(non-blocking) on inverting

[refack]

I would like to see a regression test in /parallel/

var child = spawn(process.argv[0], ['inspect', `${common.fixturesDir}/throws_error2.js`])
child.stdin.write('c\n');

that should cause is to explode (before this fix)

[refack]

Two approvals, so it's CI time: https://ci.nodejs.org/job/node-test-commit/10357/

[refack]

Regression is in inspector-helper.js:502

/data/iojs/build/workspace/node-test-commit-linuxone/nodes/rhel72-s390x/test/inspector/inspector-helper.js:502
    args.push('-e', opt_script_contents);
                    ^

ReferenceError: opt_script_contents is not defined
    at Object.exports.startNodeForInspectorTest (/data/iojs/build/workspace/node-test-commit-linuxone/nodes/rhel72-s390x/test/inspector/inspector-helper.js:502:21)
    at Object.<anonymous> (/data/iojs/build/workspace/node-test-commit-linuxone/nodes/rhel72-s390x/test/inspector/test-off-no-session.js:10:8)
    at Module._compile (module.js:569:30)

[seishun]

Fixed the regression and flipped the if/else.

Adding a test for the "inspect" command seems redundant (and less direct).

[refack]

Fixed the regression and flipped the if/else.

👍

Adding a test for the "inspect" command seems redundant (and less direct).

🤷‍♂️

[refack]

Quick CI (linuxone): https://ci.nodejs.org/job/node-test-commit-linuxone/6390/
3
2
1
and it's ✔️
_{I just love it that it finishes in less than 3 minutes}

[seishun]

Rebased on master, reworked the test a bit. PTAL again.