Update PHPUnit config

Author: swissspidy

phpunit.xml.dist

@@ -1,17 +1,26 @@
-<?xml version="1.0" encoding="UTF-8"?>
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/4.8/phpunit.xsd"
-         bootstrap="vendor/autoload.php"
-         backupGlobals="false"
-         beStrictAboutCoversAnnotation="true"
-         beStrictAboutOutputDuringTests="true"
-         beStrictAboutTestsThatDoNotTestAnything="true"
-         beStrictAboutTodoAnnotatedTests="true"
-         colors="true"
-         verbose="true">
-    <testsuites>
-        <testsuite name="default">
-            <directory suffix="Test.php">tests</directory>
-        </testsuite>
-    </testsuites>
-</phpunit>
+		 xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/4.8/phpunit.xsd"
+		 bootstrap="vendor/autoload.php"
+		 backupGlobals="false"
+		 beStrictAboutCoversAnnotation="true"
+		 beStrictAboutOutputDuringTests="true"
+		 beStrictAboutTestsThatDoNotTestAnything="true"
+		 beStrictAboutTodoAnnotatedTests="true"
+		 convertErrorsToExceptions="true"
+		 convertWarningsToExceptions="true"
+		 convertNoticesToExceptions="true"
+		 convertDeprecationsToExceptions="true"
+		 colors="true"
+		 verbose="true">
+	<testsuites>
+		<testsuite name="wp-cli/extension-command tests">
+			<directory suffix="Test.php">tests</directory>
+		</testsuite>
+	</testsuites>
+
+	<coverage processUncoveredFiles="false">
+		<include>
+			<directory suffix=".php">src</directory>
+		</include>
+	</coverage>
+</phpunit>