Merge branch 'jc/maint-rev-list-culled-boundary'

* jc/maint-rev-list-culled-boundary:
  list-objects.c: don't add an unparsed NULL as a pending tree

Conflicts:
	list-objects.c

list-objects.c

@@ -173,6 +173,11 @@ void traverse_commit_list(struct rev_info *revs,
 
 	strbuf_init(&base, PATH_MAX);
 	while ((commit = get_revision(revs)) != NULL) {
+		/*
+		 * an uninteresting boundary commit may not have its tree
+		 * parsed yet, but we are not going to show them anyway
+		 */
+		if (commit->tree)
 			add_pending_tree(revs, commit->tree);
 		show_commit(commit, data);
 	}

t/t6110-rev-list-sparse.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+
+test_description='operations that cull histories in unusual ways'
+. ./test-lib.sh
+
+test_expect_success setup '
+	test_commit A &&
+	test_commit B &&
+	test_commit C &&
+	git checkout -b side HEAD^ &&
+	test_commit D &&
+	test_commit E &&
+	git merge master
+'
+
+test_expect_success 'rev-list --first-parent --boundary' '
+	git rev-list --first-parent --boundary HEAD^..
+'
+
+test_done