Add test for AllNodesBuildParameterFactory class (#369)

* Add test for AllNodesBuildParameterFactory class

* removed unsused object nodeName

* method to maintain a clean state for subsequent tests

* Apply mvn:spotless

* Apply phrasing changes on the comments

---------

Co-authored-by: Mark Waite <[email protected]>

src/test/java/org/jvnet/jenkins/plugins/nodelabelparameter/parameterizedtrigger/AllNodesBuildParameterFactoryTest.java

@@ -0,0 +1,111 @@
+package org.jvnet.jenkins.plugins.nodelabelparameter.parameterizedtrigger;
+
+import static org.junit.Assert.*;
+
+import hudson.model.Computer;
+import hudson.model.Node;
+import hudson.plugins.parameterizedtrigger.AbstractBuildParameters;
+import hudson.slaves.DumbSlave;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+import jenkins.model.Jenkins;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.jvnet.hudson.test.JenkinsRule;
+
+public class AllNodesBuildParameterFactoryTest {
+
+    @Rule
+    public JenkinsRule j = new JenkinsRule();
+
+    private AllNodesBuildParameterFactory factory;
+
+    @Before
+    public void setUp() throws Exception {
+        factory = new AllNodesBuildParameterFactory();
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        Computer[] computers = Jenkins.get().getComputers();
+        for (Computer computer : computers) {
+            computer.setTemporarilyOffline(false, null);
+        }
+    }
+
+    @Test
+    public void getParameters_withAllNodesOnline() throws Exception {
+        DumbSlave node1 = j.createOnlineSlave();
+        DumbSlave node2 = j.createOnlineSlave();
+
+        List<AbstractBuildParameters> params = factory.getParameters(null, j.createTaskListener());
+
+        // Parameters should include 2 agents and the Jenkins controller (built-in)
+        assertEquals(3, params.size());
+    }
+
+    @Test
+    public void getParameters_withAllNodesOffline() throws Exception {
+        DumbSlave node1 = j.createSlave();
+        DumbSlave node2 = j.createSlave();
+
+        Objects.requireNonNull(node1.toComputer()).disconnect(null);
+        Objects.requireNonNull(node2.toComputer()).disconnect(null);
+
+        List<AbstractBuildParameters> params = factory.getParameters(null, j.createTaskListener());
+        // Parameters should only include the controller, since 2 agents are offline
+        // AllNodes factory only returns online agents with 1 or more executors
+        assertEquals(1, params.size());
+    }
+
+    @Test
+    public void getParameters_withMixedNodeStates() throws Exception {
+        DumbSlave node1 = j.createOnlineSlave();
+        DumbSlave node2 = j.createSlave();
+
+        Objects.requireNonNull(node2.toComputer()).disconnect(null);
+
+        List<AbstractBuildParameters> params = factory.getParameters(null, j.createTaskListener());
+        // Parameters should include the controller and the 1 online agent
+        assertEquals(2, params.size());
+    }
+
+    @Test
+    public void getParameters_withNoNodes() throws Exception {
+        Computer[] computers = Jenkins.get().getComputers();
+        for (Computer computer : computers) {
+            computer.setTemporarilyOffline(true, null);
+        }
+
+        List<AbstractBuildParameters> params = factory.getParameters(null, j.createTaskListener());
+
+        assertTrue(params.isEmpty());
+    }
+
+    @Test
+    public void getParameters_setOneExecutorAgentToZero() throws Exception {
+        DumbSlave node1 = j.createOnlineSlave();
+        DumbSlave node2 = j.createOnlineSlave();
+
+        node1.setNumExecutors(0);
+
+        List<AbstractBuildParameters> params = factory.getParameters(null, j.createTaskListener());
+
+        //    node1 will not be able to execute any builds but it will be included in the list of nodes
+        assertEquals(3, params.size());
+
+        // Create a list of nodes that can execute builds
+        List<Node> buildableNodes = new ArrayList<>();
+        for (Computer c : Jenkins.get().getComputers()) {
+            Node n = c.getNode();
+            if (n != null && c.isOnline() && c.getNumExecutors() > 0) {
+                buildableNodes.add(n);
+            }
+        }
+        // Check that the number of buildable nodes is equal to the number of parameters
+        assertEquals(buildableNodes.size(), params.size());
+    }
+}