plugin: CheckConfiguration: simple builder toString coverage test

plugin/src/test/java/net/kemitix/checkstyle/ruleset/plugin/CheckConfigurationTest.java

@@ -0,0 +1,27 @@
+package net.kemitix.checkstyle.ruleset.plugin;
+
+import org.junit.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Paul Campbell (pcampbell@kemitix.net).
+ */
+public class CheckConfigurationTest {
+
+    @Test
+    public void toStringCoverage() {
+        //given
+        final String rulesetVersion = "ruleset version";
+        final String sourceDirectory = "source directory";
+        //when
+        final String result = CheckConfiguration.builder()
+                                                .rulesetVersion(rulesetVersion)
+                                                .sourceDirectory(sourceDirectory)
+                                                .toString();
+        //then
+        System.out.println("result = " + result);
+        assertThat(result).contains("rulesetVersion=ruleset version")
+                          .contains("sourceDirectory=source directory");
+    }
+}