Add mutant catch for incompatible mixed fragment

[benalleng]

We did not have a test demonstrating that fragment delimiters could not be mixed.

Plus a test name typo

[coveralls]

Pull Request Test Coverage Report for Build 16227902588

Details

• 7 of 7 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.02%) to 85.566%

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Totals
Change from base Build 16225386088:	0.02%
Covered Lines:	7570
Relevant Lines:	8847

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💛 - Coveralls

[nothingmuch]

Derp, i forgot to check coverage on the PR that introduced that, pretty embarassing.

The test assertion seems correct but is kind of confusing, so either it needs to be simplified or I missed something and a comment is needed

[nothingmuch]

isn't this sufficient? seems like the inner match on .err() just re-asserts the same thing after convering the outer Err to a Some?

Suggested change

	let delimiter_check = check_fragment_delimiter(fragment);
	match delimiter_check {
	Err(ParseFragmentError::AmbiguousDelimiter) => {
	assert!(matches!(
	delimiter_check.err(),
	Some(ParseFragmentError::AmbiguousDelimiter)
	));
	}
	_ => panic!("Expected AmbitiousDelimiter error, got Ok or unexpected error"),
	}
	}
	assert!(matches!(
	check_fragment_delimiter(fragment),
	Err(ParseFragmentError::AmbiguousDelimiter),
	));

[benalleng]

No, it defintely can be the more simplified approach, good call