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def commitHashForBuild(build) {

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    def scmAction = build?.actions.find { action -> action instanceof jenkins.scm.api.SCMRevisionAction }

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    if (scmAction?.revision instanceof org.jenkinsci.plugins.github_branch_source.PullRequestSCMRevision) {

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        return scmAction?.revision?.pullHash

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    } else if (scmAction?.revision instanceof jenkins.plugins.git.AbstractGitSCMSource$SCMRevisionImpl) {