Tests: add code coverage configuration

* PHPUnit config: add code coverage configuration.
    By default, when there is a code coverage configuration and Xdebug is enabled, code coverage will be generated.
    For now, code coverage is set up for local use with an HTML code coverage report being generated in a `build/logs/` directory.
    Note: generating code coverage is slow.
* Git ignore the `build` directory as created by PHPUnit to store the log files.
* Adjust the "normal" test script to not generate code coverage information.
* Add a `bin/unit-tests-coverage` to run the unit tests with code coverage enabled.
* Add a Composer script to call the `unit-tests-coverage` script.

Author: jrfnl

.gitignore

@@ -1,3 +1,4 @@
+build/
 vendor/
 composer.lock
 phpcs.xml

bin/unit-tests

@@ -10,4 +10,4 @@
 #   ./bin/unit-tests
 #
 
-"$(pwd)/vendor/bin/phpunit" --filter WordPressVIPMinimum "$(pwd)/vendor/squizlabs/php_codesniffer/tests/AllTests.php"
+"$(pwd)/vendor/bin/phpunit" --filter WordPressVIPMinimum "$(pwd)/vendor/squizlabs/php_codesniffer/tests/AllTests.php" --no-coverage

bin/unit-tests-coverage

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+#
+# Run the unit tests with code coverage.
+#
+# This ensures that the logic in the VIP sniffs is covered by unit tests.
+#
+# EXAMPLE TO RUN LOCALLY:
+#
+#   ./bin/unit-tests-coverage
+#
+
+"$(pwd)/vendor/bin/phpunit" --filter WordPressVIPMinimum "$(pwd)/vendor/squizlabs/php_codesniffer/tests/AllTests.php"

composer.json

@@ -38,6 +38,7 @@
 		],
 		"phpcs": "bin/phpcs",
 		"phpunit": "bin/unit-tests",
+		"coverage": "bin/unit-tests-coverage",
 		"test": [
 			"@lint",
 			"@ruleset",

phpunit.xml.dist

@@ -1,9 +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/7.2/phpunit.xsd"
-		backupGlobals="true"
-		bootstrap="./tests/bootstrap.php"
-		beStrictAboutTestsThatDoNotTestAnything="false"
-		colors="true">
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/7.2/phpunit.xsd"
+	backupGlobals="true"
+	bootstrap="./tests/bootstrap.php"
+	beStrictAboutTestsThatDoNotTestAnything="false"
+	colors="true"
+	>
+	<testsuites>
+		<testsuite name="VIPCS_Sniffs">
+			<directory suffix="UnitTest.php">./WordPressVIPMinimum/Tests/</directory>
+		</testsuite>
+	</testsuites>
+
+	<filter>
+		<whitelist addUncoveredFilesFromWhitelist="true">
+			<directory suffix=".php">./WordPressVIPMinimum/Sniffs/</directory>
+		</whitelist>
+	</filter>
+
+	<logging>
+		<log type="coverage-html" target="./build/logs/"/>
+	</logging>
+
 </phpunit>