Fix for #4368: Add tests for LogicalNot::negate, fixes to negate regex

[kamioftea]

This is a partial fix for the issue raised in #4368 that

• Adds the tests suggested by @markrogoyski
• Fixes the existing regex to match single quotes for both strings
• Allows the match of the first single quote enclosed strings to be optional, so this also works for the __toString() use case

The above fixes to the regex allow the suggested tests to pass, however test strings with single quotes in them still show incorrect behaviour, i.e. the following test still fails:

public function testConstraintIsNotEqualStringContainsSingleQuotes(): void
{
    $string     = "a 'b' c";
    $other      = "a ''b'' c";
    $constraint = Assert::logicalNot(
        Assert::equalTo($string)
    );

    $this->assertTrue($constraint->evaluate($other, '', true));
    $this->assertFalse($constraint->evaluate($string, '', true));
    $this->assertEquals("is not equal to '{$string}'", $constraint->toString());
    $this->assertCount(1, $constraint);

    try {
        $constraint->evaluate($string);
    } catch (ExpectationFailedException $e) {
        $this->assertEquals(
            <<<EOF
Failed asserting that '{$string}' is not equal to '{$string}'.

EOF
            ,
            TestFailure::exceptionToString($e)    // Fails here
        );

        return;
    }

    $this->fail();
}

[codecov]

Codecov Report

Merging #4479 (93b3986) into 8.5 (1615054) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##                8.5    #4479   +/-   ##
=========================================
  Coverage     84.17%   84.17%           
  Complexity     3970     3970           
=========================================
  Files           154      154           
  Lines         10172    10172           
=========================================
  Hits           8562     8562           
  Misses         1610     1610           

Impacted Files	Coverage Δ	Complexity Δ
src/Framework/Constraint/LogicalNot.php	100.00% <100.00%> (ø)	16.00 <0.00> (ø)

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[sebastianbergmann]

Thank you for your contribution. I appreciate the time you invested in preparing this pull request. However, I have decided not to merge it.