[JIRA] (JENKINS-54982) Using Java8 Streams evaluates whole expression to Boolean

[matfilipow...@gmail.com (JIRA)]

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Mateusz Filipowicz created an issue   Jenkins / JENKINS-54982 Using Java8 Streams evaluates whole _expression_ to Boolean Issue Type: Bug Assignee: Unassigned Components: pipeline Created: 2018-12-03 13:53 Environment: Jenkins 2.153, Pipeline 2.6 Priority: Minor Reporter: Mateusz Filipowicz I'm trying to write a common library building Docker images from Dockerfile. I wrote a reusable global pipeline, where I'm iterating over Dockerfile lines. I tried to use Java 8 Streams, however I ended up with issue potentially related to JENKINS-26307 and JENKINS-42769, which is not related not to Groovy functional features, but Java 8 feature.  An example code used: def getMissingLabels(Map<String, String> labels) { ['label1', 'label2', 'label3', 'label4'].stream() .filter({ label -> !isLabelDefined(label, labels) }) .collect(Collectors.toList()) } Whole stream execution results in "false" boolean result, instead of a list. Even complex streams are passing through, but evaluates to "false". When using more complex stream like:   Arrays.stream(splitted) .filter { it.startsWith('LABEL') } .map { it.replaceAll('(LABEL)|"', '') } .map { it.trim() } .map { it.split('=', 2) } .collect(Collectors.toMap( { val -> val[0].toLowerCase() }, { val -> val[1] })) it enters only first filter _expression_ and does not evaluate the rest. When replaced functional style code with typical imperative style (for loop) it works.   Add Comment   This message was sent by Atlassian Jira (v7.11.2#711002-sha1:fdc329d) -- You received this message because you are subscribed to the Google Groups "Jenkins Issues" group. To unsubscribe from this group and stop receiving emails from it, send an email to jenkinsci-issues+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.