Actually it changes the build description not build name, so the post title can be confusing. Resolution is currentBuild.displayName

We will update the article with the changes.

@Hernan & @Allan that does not work in declarative pipeline.

I also tried

pipeline {
    stages {
        stage("Build"){
            steps {
                script {
                    env.currentBuild.displayName = "The name."
                    env.currentBuild.description = "The best description."
                }
                ... do whatever.
            }
        }
    }
}

But it throws NullPointerException error as shown below

java.lang.NullPointerException: Cannot set property 'displayname' on null object
	at org.codehaus.groovy.runtime.NullObject.setProperty(NullObject.java:80)
	at org.codehaus.groovy.runtime.InvokerHelper.setProperty(InvokerHelper.java:197)
	at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.setProperty(ScriptBytecodeAdapter.java:484)
	at org.kohsuke.groovy.sandbox.impl.Checker$7.call(Checker.java:347)

Hernán

In declarative you must use the script { ... } block.

pipeline {
    stages {
        stage("Build"){
            steps {
                script {
                    currentBuild.displayName = "The name."
                    currentBuild.description = "The best description."
                }
                ... do whatever.
            }
        }
    }
}

What is the equivalent for this in a declarative pipeline?

@Badal My script is missing the `agent` directive, the following should work as is:

pipeline {
    agent any
    stages {
        stage("Build"){
            steps {
                script {
                    currentBuild.displayName = "The name."
                    currentBuild.description = "The best description."
                }
            }
        }
    }
}

If it does not, please file a support request so that we can troubleshoot this further.

Note: currentBuild is a Groovy variable, not an environment variable. So you cannot use env.