From 90663ea8a631688aa32630651828ad8b205f2dbf Mon Sep 17 00:00:00 2001
From: Thanh Ha <zxiiro@linux.com>
Date: Fri, 13 Apr 2018 13:38:05 -0400
Subject: [PATCH] Document use of | character for variable defaults

Change-Id: Id20fc7a49fef6684170a73834f2df06db3f0ca7f
Signed-off-by: Thanh Ha <zxiiro@linux.com>
---
 doc/source/definition.rst                     | 10 +++++
 .../yamlparser/fixtures/variable_defaults.xml | 39 +++++++++++++++++++
 .../fixtures/variable_defaults.yaml           | 16 ++++++++
 3 files changed, 65 insertions(+)
 create mode 100644 tests/yamlparser/fixtures/variable_defaults.xml
 create mode 100644 tests/yamlparser/fixtures/variable_defaults.yaml

diff --git a/doc/source/definition.rst b/doc/source/definition.rst
index 18485905e..ce4e86df7 100644
--- a/doc/source/definition.rst
+++ b/doc/source/definition.rst
@@ -474,6 +474,16 @@ For example, having a configuration file with that option enabled:
 Will prevent JJb from failing if there are any non-initialized variables used
 and replace them with the empty string instead.
 
+.. tip::
+
+   Defaults for variables can be set by using the ``|`` character
+   ``{var|default_value}``. This is useful if we want to allow users of the
+   job-template to not have to pass a setting if there is a common default for
+   it.
+
+   Example:
+
+   .. literalinclude:: /../../tests/yamlparser/fixtures/variable_defaults.yaml
 
 Yaml Anchors & Aliases
 ^^^^^^^^^^^^^^^^^^^^^^
diff --git a/tests/yamlparser/fixtures/variable_defaults.xml b/tests/yamlparser/fixtures/variable_defaults.xml
new file mode 100644
index 000000000..74128ad5c
--- /dev/null
+++ b/tests/yamlparser/fixtures/variable_defaults.xml
@@ -0,0 +1,39 @@
+<?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>echo yolo</command>
+    </hudson.tasks.Shell>
+  </builders>
+  <publishers/>
+  <buildWrappers/>
+</project>
+<BLANKLINE>
+<?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>echo override</command>
+    </hudson.tasks.Shell>
+  </builders>
+  <publishers/>
+  <buildWrappers/>
+</project>
diff --git a/tests/yamlparser/fixtures/variable_defaults.yaml b/tests/yamlparser/fixtures/variable_defaults.yaml
new file mode 100644
index 000000000..ea25c6c80
--- /dev/null
+++ b/tests/yamlparser/fixtures/variable_defaults.yaml
@@ -0,0 +1,16 @@
+- job-template:
+    name: '{name}-variable-defaults'
+
+    builders:
+      - shell: '{script|echo yolo}'
+
+- project:
+    name: default
+    jobs:
+      - '{name}-variable-defaults'
+
+- project:
+    name: override
+    jobs:
+      - '{name}-variable-defaults'
+    script: echo override