Fix a case where getYamls would return an empty collection when… (#585)

Fix a case where getYamls would return an empty collection when in fa…

src/main/java/org/csanchez/jenkins/plugins/kubernetes/PodTemplate.java

@@ -651,7 +651,7 @@ public void setYaml(String yaml) {
 
     @Nonnull
     public List<String> getYamls() {
-        if (yamls == null) {
+        if (yamls == null || yamls.isEmpty()) {
             if (yaml != null) {
                 return Collections.singletonList(yaml);
             } else {

src/test/java/org/csanchez/jenkins/plugins/kubernetes/PodTemplateTest.java

@@ -0,0 +1,21 @@
+package org.csanchez.jenkins.plugins.kubernetes;
+
+import org.junit.Test;
+
+import static org.hamcrest.Matchers.contains;
+import static org.hamcrest.Matchers.empty;
+import static org.junit.Assert.assertThat;
+
+public class PodTemplateTest {
+    @Test
+    public void getYamlsExposesSingleYamlField() {
+        PodTemplate podTemplate = new PodTemplate();
+        assertThat(podTemplate.getYamls(), empty());
+        podTemplate.setYamls(null);
+        assertThat(podTemplate.getYamls(), empty());
+        podTemplate.setYaml("yaml");
+        assertThat(podTemplate.getYamls(), contains("yaml"));
+        podTemplate.setYaml(null);
+        assertThat(podTemplate.getYamls(), empty());
+    }
+}