refactor(): replace indexOf with includes

[zanminkian]

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• The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
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PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[coveralls]

Pull Request Test Coverage Report for Build 69ef75a0-16f0-430d-a3fa-53e6acba83a9

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 94.08%

---

Totals
Change from base Build ae79619d-0b24-423a-a05d-60ade8e7cd73:	0.0%
Covered Lines:	5658
Relevant Lines:	6014

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💛 - Coveralls

[jmcdo29]

Is there a performance improvement for using includes instead of indexOf?

[zanminkian]

Is there a performance improvement for using includes instead of indexOf?

@jmcdo29 No. Just make the intent of the code more clear. See here

[kamilmysliwiec]

LGTM

[micalevisk]

@zanminkian what do you think about the following usage of .indexOf

nest/packages/microservices/server/server-grpc.ts

Lines 257 to 267 in 775a348

	call.on('error', (e: any) => {
	// Check if error means that stream ended on other end
	const isCancelledError = String(e).toLowerCase().indexOf('cancelled');
	if (isCancelledError) {
	call.end();
	return;
	}
	// If another error then just pass it along
	req.error(e);
	});

[zanminkian]

@zanminkian what do you think about the following usage of .indexOf

nest/packages/microservices/server/server-grpc.ts

Lines 257 to 267 in 775a348

	call.on('error', (e: any) => {
	// Check if error means that stream ended on other end
	const isCancelledError = String(e).toLowerCase().indexOf('cancelled');
	if (isCancelledError) {
	call.end();
	return;
	}
	// If another error then just pass it along
	req.error(e);
	});

@micalevisk Is it a bug? I don't have too much time to understand the meaning of the code. So, I refactored some obvious code. Some code I don't understand did not edit it.

[micalevisk]

I didn't understand that code neither.

I don't know what are the values that e can have but looks like the event is said cancelled if that e is something that doesn't starts with the word 'cancelled'