Tree traversal from commit & its associated tests

src/main/java/org/kohsuke/github/GHCommit.java

@@ -37,6 +37,12 @@ public class GHCommit {
         
         private int comment_count;
 
+        static class Tree {
+            String sha;
+        }
+
+        private Tree tree;
+
         @WithBridgeMethods(value = GHAuthor.class, castRequired = true)
         public GitUser getAuthor() {
             return author;
@@ -224,6 +230,13 @@ public class GHCommit {
         return stats.deletions;
     }
 
+    /**
+     * Use this method to walk the tree
+     */
+    public GHTree getTree() throws IOException {
+        return owner.getTree(getCommitShortInfo().tree.sha);
+    }
+
     /**
      *  URL of this commit like "https://github.com/kohsuke/sandbox-ant/commit/8ae38db0ea5837313ab5f39d43a6f73de3bd9000"
      */

src/main/java/org/kohsuke/github/GHTree.java

@@ -10,6 +10,7 @@ import java.util.List;
  * https://developer.github.com/v3/git/trees/
  *
  * @author Daniel Teixeira - https://github.com/ddtxra
+ * @see GHCommit#getTree()
  * @see GHRepository#getTree(String)
  * @see GHTreeEntry#asTree()
  */
@@ -35,6 +36,19 @@ public class GHTree {
         return Collections.unmodifiableList(Arrays.asList(tree));
     }
 
+    /**
+     * Finds a tree entry by its name.
+     *
+     * IOW, find a directory entry by a file name.
+     */
+    public GHTreeEntry getEntry(String path) {
+        for (GHTreeEntry e : tree) {
+            if (e.getPath().equals(path))
+                return e;
+        }
+        return null;
+    }
+
     /**
      * Returns true if the number of items in the tree array exceeded the GitHub maximum limit. 
      * @return true true if the number of items in the tree array exceeded the GitHub maximum limit otherwise false.

src/test/java/org/kohsuke/github/AppTest.java

@@ -363,6 +363,11 @@ public class AppTest extends AbstractGitHubApiTestBase {
         assertEquals(48,f.getLinesChanged());
         assertEquals("modified",f.getStatus());
         assertEquals("changelog.html", f.getFileName());
+
+        // walk the tree
+        GHTree t = commit.getTree();
+        assertThat(IOUtils.toString(t.getEntry("todo.txt").readAsBlob()), containsString("executor rendering"));
+        assertNotNull(t.getEntry("war").asTree());
     }
 
     @Test