FindBugs

Author: jglick

pom.xml

@@ -63,7 +63,7 @@
     </pluginRepositories>
     <properties>
         <jenkins.version>1.642.3</jenkins.version>
-        <workflow-step-api-plugin.version>2.11</workflow-step-api-plugin.version>
+        <workflow-step-api-plugin.version>2.12-20170630.151937-1</workflow-step-api-plugin.version> <!-- TODO https://github.com/jenkinsci/workflow-step-api-plugin/pull/27 -->
         <workflow-cps-plugin.version>2.32</workflow-cps-plugin.version>
         <workflow-support-plugin.version>2.14</workflow-support-plugin.version>
     </properties>

src/main/java/org/jenkinsci/plugins/workflow/steps/CoreStep.java

@@ -125,7 +125,8 @@ private <T extends Describable<T>,D extends Descriptor<T>> void populate(List<De
         }
 
         @Override public String argumentsToString(Map<String, Object> namedArgs) {
-            return super.argumentsToString(delegateArguments(namedArgs.get("delegate")));
+            Map<String, Object> delegateArguments = delegateArguments(namedArgs.get("delegate"));
+            return delegateArguments != null ? super.argumentsToString(delegateArguments) : null;
         }
 
         @SuppressWarnings("unchecked")

src/main/java/org/jenkinsci/plugins/workflow/steps/CoreWrapperStep.java

@@ -162,7 +162,8 @@ public Collection<BuildWrapperDescriptor> getApplicableDescriptors() {
         }
 
         @Override public String argumentsToString(Map<String, Object> namedArgs) {
-            return super.argumentsToString(CoreStep.DescriptorImpl.delegateArguments(namedArgs.get("delegate")));
+            Map<String, Object> delegateArguments = CoreStep.DescriptorImpl.delegateArguments(namedArgs.get("delegate"));
+            return delegateArguments != null ? super.argumentsToString(delegateArguments) : null;
         }
 
     }