CloneOption.honorRefspec can also be useful

Author: jglick

src/main/resources/org/jenkinsci/plugins/workflow/libs/SCMBasedRetriever/help-clone.html

@@ -2,7 +2,7 @@
     If checked, every build performs a fresh clone of the SCM rather than locking and updating a common copy.
     No changelog will be computed.
     For Git, you are advised to add <b>Advanced clone behaviors</b>
-    and then check <b>Shallow clone</b> and uncheck <b>Fetch tags</b>
+    and then check <b>Shallow clone</b> and <b>Honor refspec on initial clone</b> and uncheck <b>Fetch tags</b>
     to make the clone much faster.
     You may still enable <b>Cache fetched versions on controller for quick retrieval</b> if you prefer.
 </div>

src/test/java/org/jenkinsci/plugins/workflow/libs/SCMSourceRetrieverTest.java

@@ -62,6 +62,7 @@
 import static hudson.ExtensionList.lookupSingleton;
 import hudson.plugins.git.extensions.impl.CloneOption;
 import jenkins.plugins.git.traits.CloneOptionTrait;
+import jenkins.plugins.git.traits.RefSpecsSCMSourceTrait;
 import jenkins.scm.api.trait.SCMSourceTrait;
 import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.containsInAnyOrder;
@@ -379,7 +380,9 @@ public static class BasicSCMSource extends SCMSource {
         sampleRepo.git("add", ".");
         sampleRepo.git("commit", "--message=init");
         GitSCMSource src = new GitSCMSource(sampleRepo.toString());
-        src.setTraits(List.<SCMSourceTrait>of(new CloneOptionTrait(new CloneOption(true, true, null, null))));
+        CloneOption cloneOption = new CloneOption(true, true, null, null);
+        cloneOption.setHonorRefspec(true);
+        src.setTraits(List.<SCMSourceTrait>of(new CloneOptionTrait(cloneOption), new RefSpecsSCMSourceTrait("+refs/heads/master:refs/remotes/origin/master")));
         SCMSourceRetriever scm = new SCMSourceRetriever(src);
         LibraryConfiguration lc = new LibraryConfiguration("echoing", scm);
         lc.setIncludeInChangesets(false);
@@ -392,6 +395,7 @@ public static class BasicSCMSource extends SCMSource {
         r.assertLogContains("something special", b);
         r.assertLogContains("Using shallow clone with depth 1", b);
         r.assertLogContains("Avoid fetching tags", b);
+        r.assertLogNotContains("+refs/heads/*:refs/remotes/origin/*", b);
         // Fails to reproduce presence of *.jar.tmp@tmp; probably specific to use of GIT_ASKPASS:
         assertThat(new File(b.getRootDir(), "libs").list(), arrayContaining(matchesPattern("[0-9a-f]{64}[.]jar")));
     }