Adds @post and permission check

Author: froque

src/main/java/org/jenkinsci/plugins/vb6/VB6Builder.java

@@ -5,26 +5,24 @@
 import hudson.Extension;
 import hudson.FilePath;
 import hudson.model.AbstractProject;
-import hudson.model.Result;
+import hudson.model.Item;
 import hudson.model.Run;
 import hudson.model.TaskListener;
 import hudson.tasks.Builder;
 import hudson.tasks.BuildStepDescriptor;
 import hudson.util.ArgumentListBuilder;
 import hudson.util.FormValidation;
+import jenkins.model.Jenkins;
 import jenkins.tasks.SimpleBuildStep;
 import net.sf.json.JSONObject;
 import org.jenkinsci.Symbol;
 import org.kohsuke.stapler.DataBoundConstructor;
 import org.kohsuke.stapler.DataBoundSetter;
 import org.kohsuke.stapler.QueryParameter;
 import org.kohsuke.stapler.StaplerRequest2;
+import org.kohsuke.stapler.verb.POST;
 
-import java.io.File;
 import java.io.IOException;
-import java.nio.file.Files;
-
-import static java.io.File.createTempFile;
 
 /**
  * Sample {@link Builder}.
@@ -165,7 +163,10 @@ public DescriptorImpl() {
         }
 
 
+        @POST
         public FormValidation doCheckProjectFile(@QueryParameter String value) {
+            Jenkins.get().checkPermission(Item.CONFIGURE);
+
             if(Strings.isNullOrEmpty(value)){
                 return FormValidation.error("value is empty");
             } else{

src/test/java/org/jenkinsci/plugins/vb6/VB6BuilderTest.java

@@ -7,6 +7,8 @@
 import hudson.model.FreeStyleProject;
 import hudson.model.Result;
 import hudson.model.queue.QueueTaskFuture;
+import org.htmlunit.html.HtmlForm;
+import org.htmlunit.html.HtmlPage;
 import org.jenkinsci.plugins.workflow.cps.CpsFlowDefinition;
 import org.jenkinsci.plugins.workflow.job.WorkflowJob;
 import org.jenkinsci.plugins.workflow.job.WorkflowRun;
@@ -15,13 +17,31 @@
 import org.jvnet.hudson.test.JenkinsRule;
 import org.jvnet.hudson.test.junit.jupiter.WithJenkins;
 import org.jvnet.hudson.test.recipes.LocalData;
+import org.xml.sax.SAXException;
 
+import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Paths;
 
 @WithJenkins
 public class VB6BuilderTest {
 
+    @Test
+    void configRoundTrip(JenkinsRule j) throws Exception {
+        FreeStyleProject p = j.createFreeStyleProject();
+        VB6Builder orig = new VB6Builder("projectFile1.vbp");
+        p.getBuildersList().add(orig);
+
+        try (JenkinsRule.WebClient webClient = j.createWebClient()) {
+            HtmlPage page = webClient.getPage(p, "configure");
+            HtmlForm form = page.getFormByName("config");
+            j.submit(form);
+        }
+
+        j.assertEqualBeans(orig, p.getBuildersList().get(VB6Builder.class), "projectFile");
+
+    }
+
     @Test
     void testUnix(JenkinsRule j) throws Exception {
         Assumptions.assumeFalse(Functions.isWindows());