Prevent creation of empty parameters for Repo

Only manifest-url is required for the Repo plugin, all other parameters
are optional, or should at least not generate empty tags, because the
actual 'repo' tool will be called with empty parameters, leading to
a failed execution.

This was introduced with a34bd67ef7.
Before that change, empty strings did not generate XML entries.

Change-Id: Ia66845cb71b01c8e26285ed2eabb1ef32622e3e1
Story: 2000727

jenkins_jobs/modules/scm.py

@@ -612,18 +612,18 @@ def repo(registry, xml_parent, data):
     Requires the Jenkins :jenkins-wiki:`Repo Plugin <Repo+Plugin>`.
 
     :arg str manifest-url: URL of the repo manifest (required)
-    :arg str manifest-branch: The branch of the manifest to use (default '')
+    :arg str manifest-branch: The branch of the manifest to use (optional)
     :arg str manifest-file: Initial manifest file to use when initialising
-        (default '')
+        (optional)
     :arg str manifest-group: Only retrieve those projects in the manifest
-        tagged with the provided group name (default '')
+        tagged with the provided group name (optional)
     :arg list(str) ignore-projects: a list of projects in which changes would
-        not be considered to trigger a build when pooling (default '')
+        not be considered to trigger a build when pooling (optional)
     :arg str destination-dir: Location relative to the workspace root to clone
-        under (default '')
-    :arg str repo-url: custom url to retrieve the repo application (default '')
+        under (optional)
+    :arg str repo-url: custom url to retrieve the repo application (optional)
     :arg str mirror-dir: Path to mirror directory to reference when
-        initialising (default '')
+        initialising (optional)
     :arg int jobs: Number of projects to fetch simultaneously (default 0)
     :arg int depth: Specify the depth in history to sync from the source. The
         default is to sync all of the history. Use 1 to just sync the most
@@ -643,7 +643,7 @@ def repo(registry, xml_parent, data):
     :arg bool show-all-changes: When this is checked --first-parent is no
         longer passed to git log when determining changesets (default false)
     :arg str local-manifest: Contents of .repo/local_manifest.xml, written
-        prior to calling sync (default '')
+        prior to calling sync (optional)
 
     Example:
 
@@ -656,12 +656,6 @@ def repo(registry, xml_parent, data):
     mapping = [
         # option, xml name, default value
         ('manifest-url', 'manifestRepositoryUrl', None),
-        ('manifest-branch', 'manifestBranch', ''),
-        ('manifest-file', 'manifestFile', ''),
-        ('manifest-group', 'manifestGroup', ''),
-        ('destination-dir', 'destinationDir', ''),
-        ('repo-url', 'repoUrl', ''),
-        ('mirror-dir', 'mirrorDir', ''),
         ('jobs', 'jobs', 0),
         ('depth', 'depth', 0),
         ('current-branch', 'currentBranch', True),
@@ -671,10 +665,21 @@ def repo(registry, xml_parent, data):
         ('no-tags', 'noTags', False),
         ('trace', 'trace', False),
         ('show-all-changes', 'showAllChanges', False),
-        ('local-manifest', 'localManifest', ''),
     ]
     convert_mapping_to_xml(scm, data, mapping, fail_required=True)
 
+    optional_mapping = [
+        # option, xml name, default value
+        ('manifest-branch', 'manifestBranch', None),
+        ('manifest-file', 'manifestFile', None),
+        ('manifest-group', 'manifestGroup', None),
+        ('destination-dir', 'destinationDir', None),
+        ('repo-url', 'repoUrl', None),
+        ('mirror-dir', 'mirrorDir', None),
+        ('local-manifest', 'localManifest', None),
+    ]
+    convert_mapping_to_xml(scm, data, optional_mapping, fail_required=False)
+
     # ignore-projects does not follow the same pattern of the other parameters,
     # so process it here:
     ip = XML.SubElement(scm, 'ignoreProjects', {'class': 'linked-hash-set'})

tests/macros/fixtures/scm/multi-scms002.xml

@@ -12,12 +12,6 @@
     <scms>
       <hudson.plugins.repo.RepoScm>
         <manifestRepositoryUrl>https://example.com/project/</manifestRepositoryUrl>
-        <manifestBranch>stable</manifestBranch>
-        <manifestFile>repo.xml</manifestFile>
-        <manifestGroup>drivers</manifestGroup>
-        <destinationDir>build</destinationDir>
-        <repoUrl>https://internal.net/projects/repo</repoUrl>
-        <mirrorDir>~/git/project/</mirrorDir>
         <jobs>3</jobs>
         <depth>2</depth>
         <currentBranch>false</currentBranch>
@@ -27,7 +21,12 @@
         <noTags>false</noTags>
         <trace>false</trace>
         <showAllChanges>false</showAllChanges>
-        <localManifest/>
+        <manifestBranch>stable</manifestBranch>
+        <manifestFile>repo.xml</manifestFile>
+        <manifestGroup>drivers</manifestGroup>
+        <destinationDir>build</destinationDir>
+        <repoUrl>https://internal.net/projects/repo</repoUrl>
+        <mirrorDir>~/git/project/</mirrorDir>
         <ignoreProjects class="linked-hash-set">
           <string/>
         </ignoreProjects>

tests/scm/fixtures/repo001.xml

@@ -2,12 +2,6 @@
 <project>
   <scm class="hudson.plugins.repo.RepoScm">
     <manifestRepositoryUrl>https://example.com/project/</manifestRepositoryUrl>
-    <manifestBranch>stable</manifestBranch>
-    <manifestFile>repo.xml</manifestFile>
-    <manifestGroup>drivers</manifestGroup>
-    <destinationDir>build</destinationDir>
-    <repoUrl>https://internal.net/projects/repo</repoUrl>
-    <mirrorDir>~/git/project/</mirrorDir>
     <jobs>3</jobs>
     <depth>0</depth>
     <currentBranch>false</currentBranch>
@@ -17,6 +11,12 @@
     <noTags>true</noTags>
     <trace>true</trace>
     <showAllChanges>true</showAllChanges>
+    <manifestBranch>stable</manifestBranch>
+    <manifestFile>repo.xml</manifestFile>
+    <manifestGroup>drivers</manifestGroup>
+    <destinationDir>build</destinationDir>
+    <repoUrl>https://internal.net/projects/repo</repoUrl>
+    <mirrorDir>~/git/project/</mirrorDir>
     <localManifest>&lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
 &lt;manifest&gt;
   &lt;project path=&quot;external/project&quot; name=&quot;org/project&quot;