pipeline {
   agent any 
   node {
      checkout scm
   }
   stages {   
      stage ("Unit Tests") {
         steps {
            sh "./node_modules/.bin/mocha --reporter mocha-junit-reporter --reporter-options mochaFile=./testResults/results.xml"
            junit allowEmptyResults: true, testResults: 'testResults/results.xml'
         }
      }
   }
}

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
WorkflowScript: 1: Undefined section "node" @ line 1, column 1.
   pipeline {
   ^

1 error

	at org.codehaus.groovy.control.ErrorCollector.failIfErrors(ErrorCollector.java:310)
	at org.codehaus.groovy.control.CompilationUnit.applyToPrimaryClassNodes(CompilationUnit.java:1073)
	at org.codehaus.groovy.control.CompilationUnit.doPhaseOperation(CompilationUnit.java:591)
	at org.codehaus.groovy.control.CompilationUnit.processPhaseOperations(CompilationUnit.java:569)
	at org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:546)
	at groovy.lang.GroovyClassLoader.doParseClass(GroovyClassLoader.java:298)
	at groovy.lang.GroovyClassLoader.parseClass(GroovyClassLoader.java:268)
	at groovy.lang.GroovyShell.parseClass(GroovyShell.java:688)
	at groovy.lang.GroovyShell.parse(GroovyShell.java:700)
	at org.jenkinsci.plugins.workflow.cps.CpsGroovyShell.reparse(CpsGroovyShell.java:67)
	at org.jenkinsci.plugins.workflow.cps.CpsFlowExecution.parseScript(CpsFlowExecution.java:430)
	at org.jenkinsci.plugins.workflow.cps.CpsFlowExecution.start(CpsFlowExecution.java:393)
	at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:238)
	at hudson.model.ResourceController.execute(ResourceController.java:98)
	at hudson.model.Executor.run(Executor.java:405)
Finished: FAILURE