Add support for {% include %} in Jinja2 templates

This allows the use of the {% include %} tag[0] within Jinja2 templates,
with the same search path used for looking up other templates (i.e. the
one which LocalLoader is instantiated with).

[0] http://jinja.pocoo.org/docs/2.9/templates/#include

Change-Id: I0403c385ee317e1460a80a9bf717aa4712f37e2f

jenkins_jobs/local_yaml.py

@@ -324,7 +324,7 @@ class J2String(BaseYAMLObject):
 
     @classmethod
     def from_yaml(cls, loader, node):
-        return Jinja2Loader(node.value)
+        return Jinja2Loader(node.value, loader.search_path)
 
 
 class YamlInclude(BaseYAMLObject):
@@ -423,7 +423,7 @@ class YamlIncludeJinja2(YamlIncludeRaw):
         contents = cls._open_file(loader, node)
         if isinstance(contents, LazyLoader):
             return contents
-        return Jinja2Loader(contents)
+        return Jinja2Loader(contents, loader.search_path)
 
 
 class DeprecatedTag(BaseYAMLObject):
@@ -456,9 +456,12 @@ class CustomLoader(object):
 
 class Jinja2Loader(CustomLoader):
     """A loader for Jinja2-templated files."""
-    def __init__(self, contents):
+
+    def __init__(self, contents, search_path):
         self._template = jinja2.Template(contents)
         self._template.environment.undefined = jinja2.StrictUndefined
+        self._template.environment.loader = jinja2.FileSystemLoader(
+            search_path)
 
     def format(self, **kwargs):
         return self._template.render(kwargs)

tests/yamlparser/fixtures/jinja-include01.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<project>
+  <actions/>
+  <description>&lt;!-- Managed by Jenkins Job Builder --&gt;</description>
+  <keepDependencies>false</keepDependencies>
+  <blockBuildWhenDownstreamBuilding>false</blockBuildWhenDownstreamBuilding>
+  <blockBuildWhenUpstreamBuilding>false</blockBuildWhenUpstreamBuilding>
+  <concurrentBuild>false</concurrentBuild>
+  <canRoam>true</canRoam>
+  <properties/>
+  <scm class="hudson.scm.NullSCM"/>
+  <builders>
+    <hudson.tasks.Shell>
+      <command>test variable
+a
+b
+c
+</command>
+    </hudson.tasks.Shell>
+  </builders>
+  <publishers/>
+  <buildWrappers/>
+</project>

tests/yamlparser/fixtures/jinja-include01.yaml

@@ -0,0 +1,15 @@
+- builder:
+    name: test-builder
+    builders:
+        - shell:
+            !include-jinja2: jinja-include01.yaml.inc
+
+- job:
+    name: test-job
+    builders:
+        - test-builder:
+            var: "test variable"
+            test_list:
+                - a
+                - b
+                - c

tests/yamlparser/fixtures/jinja-include01.yaml.inc

@@ -0,0 +1 @@
+{% include 'jinja01.yaml.inc' %}

tests/yamlparser/fixtures/jinja-include02.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<project>
+  <actions/>
+  <description>&lt;!-- Managed by Jenkins Job Builder --&gt;</description>
+  <keepDependencies>false</keepDependencies>
+  <blockBuildWhenDownstreamBuilding>false</blockBuildWhenDownstreamBuilding>
+  <blockBuildWhenUpstreamBuilding>false</blockBuildWhenUpstreamBuilding>
+  <concurrentBuild>false</concurrentBuild>
+  <canRoam>true</canRoam>
+  <properties/>
+  <scm class="hudson.scm.NullSCM"/>
+  <builders>
+    <hudson.tasks.Shell>
+      <command>test variable
+a
+b
+c
+</command>
+    </hudson.tasks.Shell>
+  </builders>
+  <publishers/>
+  <buildWrappers/>
+</project>

tests/yamlparser/fixtures/jinja-include02.yaml

@@ -0,0 +1,14 @@
+- builder:
+    name: test-builder
+    builders:
+        - shell: !j2: "{% include 'jinja01.yaml.inc' %}"
+
+- job:
+    name: test-job
+    builders:
+        - test-builder:
+            var: "test variable"
+            test_list:
+                - a
+                - b
+                - c