[JENKINS-34755] - Add some tests

core/src/main/java/jenkins/util/SystemProperties.java

@@ -92,8 +92,8 @@ public class SystemProperties {
         if (value != null) {
             if (LOGGER.isLoggable(Level.CONFIG)) {
                 LOGGER.log(Level.CONFIG, "Property (system): {0} => {1}", new Object[] {key, value});
-                return value;
             }
+            return value;
         }
         
         value = tryGetValueFromContext(key);
@@ -127,8 +127,8 @@ public class SystemProperties {
         if (value != null) {
             if (LOGGER.isLoggable(Level.CONFIG)) {
                 LOGGER.log(Level.CONFIG, "Property (system): {0} => {1}", new Object[] {key, value});
-                return value;
             }
+            return value;
         } 
         
         value = tryGetValueFromContext(key);

test/src/test/java/jenkins/util/SystemPropertiesTest.java

+/*
+ * The MIT License
+ *
+ * Copyright (c) 2016 CloudBees, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package jenkins.util;
+
+import javax.servlet.ServletContext;
+import net.sourceforge.htmlunit.corejs.javascript.RhinoSecurityManager;
+import static org.hamcrest.Matchers.*;
+import static org.junit.Assert.assertThat;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.jvnet.hudson.test.JenkinsRule;
+
+/**
+ * Tests of {@link SystemProperties}.
+ * @author Oleg Nenashev
+ */
+public class SystemPropertiesTest {
+    
+    @Rule
+    public JenkinsRule j = new JenkinsRule();
+    
+    @Before
+    public void setUp() {
+        SystemProperties.initialize(j.jenkins.servletContext);
+    }
+    
+    @Test
+    public void shouldReturnNullIfUndefined() throws Exception {
+        assertThat("Properties should be null by default", 
+                SystemProperties.getString("foo.bar"), nullValue());
+    }
+    
+    @Test
+    public void shouldInitializeFromSystemProperty() throws Exception {
+        System.setProperty("foo.bar", "myVal");
+        assertThat("System property should assign the value", 
+                SystemProperties.getString("foo.bar"), equalTo("myVal"));
+    }
+    
+    @Test
+    public void shouldInitializeFromContext() throws Exception {
+        ServletContext c = j.jenkins.servletContext;
+        assertThat("System property should assign the value", 
+                SystemProperties.getString("install-wizard-path"), equalTo("jsbundles/pluginSetupWizard"));
+    }
+    
+    @Test
+    public void shouldUseSystemPropertyAsAHighPriority() throws Exception {
+        ServletContext c = j.jenkins.servletContext;
+        System.setProperty("install-wizard-path", "myVal2");
+        assertThat("System property should take system property with a high priority", 
+                SystemProperties.getString("install-wizard-path"), equalTo("myVal2"));
+    }
+}