Support the use of lists in trigger-build builder.

Since Jenkins parameterized build trigger buildstep supports comma-separated
list of jobs to build, this simply joins a list of jobs specified in JJB yaml on
a comma.

Change-Id: I0a65f3497d4a68d798ea29c580b6217bbecfe222

jenkins_jobs/modules/builders.py

@@ -282,7 +282,7 @@ def trigger_builds(parser, xml_parent, data):
     Requires the Jenkins :jenkins-wiki:`Parameterized Trigger Plugin
     <Parameterized+Trigger+Plugin>`.
 
-    :arg str project: the Jenkins project to trigger
+    :arg list project: the Jenkins project to trigger
     :arg str predefined-parameters:
       key/value pairs to be passed to the job (optional)
     :arg list bool-parameters:
@@ -355,6 +355,12 @@ def trigger_builds(parser, xml_parent, data):
 
     Examples:
 
+    Basic usage with yaml list of projects.
+
+    .. literalinclude::
+       /../../tests/builders/fixtures/trigger-builds/project-list.yaml
+       :language: yaml
+
     Basic usage with passing svn revision through.
 
     .. literalinclude:: /../../tests/builders/fixtures/trigger-builds001.yaml
@@ -515,7 +521,11 @@ def trigger_builds(parser, xml_parent, data):
                         'ignore-offline-nodes', True)).lower()
 
         projects = XML.SubElement(tconfig, 'projects')
-        projects.text = project_def['project']
+        if isinstance(project_def['project'], list):
+            projects.text = ",".join(project_def['project'])
+        else:
+            projects.text = project_def['project']
+
         condition = XML.SubElement(tconfig, 'condition')
         condition.text = 'ALWAYS'
         trigger_with_no_params = XML.SubElement(tconfig,

tests/builders/fixtures/trigger-builds/project-list.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<project>
+  <builders>
+    <hudson.plugins.parameterizedtrigger.TriggerBuilder>
+      <configs>
+        <hudson.plugins.parameterizedtrigger.BlockableBuildTriggerConfig>
+          <configs>
+            <hudson.plugins.parameterizedtrigger.CurrentBuildParameters/>
+          </configs>
+          <projects>foo,bar,baz</projects>
+          <condition>ALWAYS</condition>
+          <triggerWithNoParameters>false</triggerWithNoParameters>
+          <buildAllNodesWithLabel>false</buildAllNodesWithLabel>
+        </hudson.plugins.parameterizedtrigger.BlockableBuildTriggerConfig>
+      </configs>
+    </hudson.plugins.parameterizedtrigger.TriggerBuilder>
+  </builders>
+</project>

tests/builders/fixtures/trigger-builds/project-list.yaml

@@ -0,0 +1,7 @@
+builders:
+  - trigger-builds:
+    - project:
+        - "foo"
+        - "bar"
+        - "baz"
+      current-parameters: true