This plugin intends to help with development of Shared Libraries.

• Basic Groovy compilation to validate source code

• Unit test using Jenkins Pipeline Unit

• Usage of plugin and Jenkins core classes in library

• @Grab support for libraries (testing limited to @JenkinsRule style integration tests due to an issue)

• @NonCPS annotation can be used in main source code

• Source code generation to assist with development (for example, com.mkobit.jenkins.pipelines.codegen.LocalLibraryRetriever)

• Integration test using the Jenkins Test Harness

• Code completion in IDE

See the example repository for a demonstration of using this plugin.

1. Consume plugin from Gradle plugin portal

   plugins {
     id("com.mkobit.jenkins.pipelines.shared-library") version "x.x.x"
   }

2. Set up preferred test dependencies (for example, JUnit or Spock)

   repositories {
     jcenter()
   }
   
   dependencies {
     testImplementation(group: 'junit', name: 'junit', version: '4.12')
   }

3. Write some shared library code

   Library class - src/com/mkobit/LibHelper.groovy

   package com.mkobit
   
   class LibHelper {
     private script
     LibHelper(script) {
       this.script = script
     }
   
     void sayHelloTo(String name) {
       script.echo("LibHelper says hello to $name!")
     }
   }

   Global variable - vars/myGlobal.groovy

   def call() {
     echo 'Hello from myGlobal'
   }

4. Write integration tests by utilizing a local JenkinsRule and setting up the shared library

   Integration tests - test/integration/groovy/com/mkobit/JenkinsGlobalLibraryUsageTest.groovy

   package com.mkobit
   
   import com.mkobit.jenkins.pipelines.codegen.LocalLibraryRetriever
   import org.jenkinsci.plugins.workflow.libs.GlobalLibraries
   import org.jenkinsci.plugins.workflow.libs.LibraryConfiguration
   import org.jenkinsci.plugins.workflow.libs.LibraryRetriever
   import org.jenkinsci.plugins.workflow.cps.CpsFlowDefinition
   import org.jenkinsci.plugins.workflow.job.WorkflowJob
   import org.jenkinsci.plugins.workflow.job.WorkflowRun
   import org.junit.Before
   import org.junit.Rule
   import org.junit.Test
   import org.jvnet.hudson.test.JenkinsRule
   
   class JenkinsGlobalLibraryUsageTest {
   
     @Rule
     public JenkinsRule rule = new JenkinsRule()
   
     @Before
     void configureGlobalLibraries() {
       rule.timeout = 30
       final LibraryRetriever retriever = new LocalLibraryRetriever()
       final LibraryConfiguration localLibrary =
         new LibraryConfiguration('testLibrary', retriever)
       localLibrary.implicit = true
       localLibrary.defaultVersion = 'unused'
       localLibrary.allowVersionOverride = false
       GlobalLibraries.get().setLibraries(Collections.singletonList(localLibrary))
     }
   
     @Test
     void testingMyLibrary() {
       CpsFlowDefinition flow = new CpsFlowDefinition('''
           import com.mkobit.LibHelper
   
           final libHelper = new LibHelper(this)
           libHelper.sayHelloTo('mkobit')
       '''.stripIndent(), true)
       WorkflowJob workflowJob = rule.createProject(WorkflowJob, 'project')
       workflowJob.definition = flow
       WorkflowRun result = rule.buildAndAssertSuccess(workflowJob)
       rule.assertLogContains('LibHelper says hello to mkobit!', result)
     }
   
     @Test
     void testingMyGlobalVar() {
       CpsFlowDefinition flow = new CpsFlowDefinition('''
           import myGlobal
   
           myGlobal()
       '''.stripIndent(), true)
       WorkflowJob workflowJob = rule.createProject(WorkflowJob, 'project')
       workflowJob.definition = flow
       WorkflowRun result = rule.buildAndAssertSuccess(workflowJob)
       rule.assertLogContains('Hello from myGlobal', result)
     }
   }

The sharedLibrary extension can be used to add additional plugin dependencies, Groovy version dependency, Jenkins Core dependency, etc. As of right now, most of the workflow-type plugins are automatically added based on default or configured versions. See the code for full details, but here is an example of what you can configure: