[JENKINS-23641] - Direct tests for the issue

Signed-off-by: Oleg Nenashev <o.v.nenashev@gmail.com>

src/main/java/com/cloudbees/jenkins/GitHubCommitNotifier.java

@@ -52,12 +52,12 @@ public boolean perform(AbstractBuild<?, ?> build, Launcher launcher, BuildListen
 
         BuildData buildData = build.getAction(BuildData.class);
         if (buildData == null) {
-            throw new IOException("Cannot retrieve Git metadata for the build");
+            throw new IOException(Messages.GitHubCommitNotifier_NoBuildDataError());
         }
         final Revision lastBuildRevision = buildData.getLastBuiltRevision();
         final ObjectId sha1 = lastBuildRevision != null ? lastBuildRevision.getSha1() : null;
         if (sha1 == null) { // Nowhere to report => fail the build
-            throw new IOException("Cannot determine sha1 of the commit. The status cannot be reported");
+            throw new IOException(Messages.GitHubCommitNotifier_NoLastRevisionError());
         }
 
         for (GitHubRepositoryName name : GitHubRepositoryNameContributor.parseAssociatedNames(build.getProject())) {

src/main/resources/com/cloudbees/jenkins/Messages.properties

@@ -2,3 +2,5 @@ CommitNotifier.Success=Build {0} succeeded in {1}
 CommitNotifier.Unstable=Build {0} found unstable in {1}
 CommitNotifier.Failed=Build {0} failed in {1}
 GitHubCommitNotifier.SettingCommitStatus=Setting commit status on GitHub for {0}
+GitHubCommitNotifier.NoBuildDataError=Cannot retrieve Git metadata for the build
+GitHubCommitNotifier.NoLastRevisionError=Cannot determine sha1 of the commit. The status cannot be reported

src/test/java/com/cloudbees/jenkins/GitHubCommitNotifierTest.java

@@ -0,0 +1,51 @@
+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+
+package com.cloudbees.jenkins;
+
+import hudson.model.Build;
+import hudson.model.FreeStyleProject;
+import hudson.model.Result;
+import hudson.plugins.git.GitSCM;
+import org.junit.Rule;
+import org.junit.Test;
+import org.jvnet.hudson.test.Bug;
+import org.jvnet.hudson.test.HudsonTestCase;
+import org.jvnet.hudson.test.JenkinsRule;
+
+/**
+ * Tests for {@link GitHubCommitNotifier}.
+ * @author Oleg Nenashev <o.v.nenashev@gmail.com>
+ */
+public class GitHubCommitNotifierTest extends HudsonTestCase {
+
+  //  @Rule
+  //  public JenkinsRule r = new JenkinsRule();
+
+
+    @Test
+    @Bug(23641)
+    public void testNoBuildData() throws Exception, InterruptedException  {
+        FreeStyleProject prj = createFreeStyleProject("23641_noBuildData");
+        prj.getPublishersList().add(new GitHubCommitNotifier());
+        Build b = prj.scheduleBuild2(0).get();
+        assertBuildStatus(Result.FAILURE, b);
+        assertLogContains(Messages.GitHubCommitNotifier_NoBuildDataError(), b);
+    }
+
+    @Test
+    @Bug(23641)
+    public void testNoBuildRevision() throws Exception, InterruptedException {
+        FreeStyleProject prj = createFreeStyleProject();
+        prj.setScm(new GitSCM("http://non.existent.git.repo.nowhere/repo.git"));
+        prj.getPublishersList().add(new GitHubCommitNotifier());
+        Build b = prj.scheduleBuild2(0).get();
+        assertBuildStatus(Result.FAILURE, b);
+        assertLogContains(Messages.GitHubCommitNotifier_NoLastRevisionError(), b);
+    }
+
+
+}