Description

fix #15327

magic-string .slice() may throw an error if the sliced string has removed content. I added a try-catch to fix it.

I was thinking if we could check against the plain string instead, but seems risky if there's added content later in magic-string.

I also refactored the code a bit.

Additional context

What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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