psalm.xml

<?xml version="1.0"?>
<psalm
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns="https://getpsalm.org/schema/config"
        xsi:schemaLocation="https://getpsalm.org/schema/config ../../vendor-bin/psalm/vendor/vimeo/psalm/config.xsd"
        cacheDirectory="dist/.psalm"
        findUnusedVariablesAndParams="true"
        findUnusedCode="true"
        findUnusedPsalmSuppress="true"
        findUnusedBaselineEntry="true"
        ensureArrayIntOffsetsExist="true"
        ensureArrayStringOffsetsExist="true"
        ignoreInternalFunctionFalseReturn="false"
        ignoreInternalFunctionNullReturn="false"
        strictBinaryOperands="true">

    <plugins>
        <pluginClass class="Psalm\PhpUnitPlugin\Plugin" />
    </plugins>

    <projectFiles>
        <directory name="src"/>
        <directory name="tests"/>

        <ignoreFiles>
            <file name="src/StrictPHPUnit9Extension.php"/>
        </ignoreFiles>
    </projectFiles>

    <issueHandlers>
        <MissingParamType>
            <errorLevel type="suppress">
                <file name="tests/StrictScalarComparatorTest.php"/>
            </errorLevel>
        </MissingParamType>

        <PossiblyUnusedMethod>
            <!-- This is for the PHPUnit data providers; see https://github.com/psalm/psalm-plugin-phpunit/issues/131 -->
            <errorLevel type="suppress">
                <directory name="tests"/>
            </errorLevel>
        </PossiblyUnusedMethod>

        <PropertyNotSetInConstructor>
            <errorLevel type="suppress">
                <file name="src/StrictScalarComparator.php"/>
            </errorLevel>
        </PropertyNotSetInConstructor>

        <UnusedClass errorLevel="suppress"/>
        <UnusedConstructor errorLevel="suppress"/>
    </issueHandlers>
</psalm>