Changed Exception Type

Changed Exception type and added a comment

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

@@ -2,10 +2,12 @@ package org.kohsuke.github;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.databind.JsonMappingException;
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import java.io.IOException;
 import java.net.URL;
 import java.util.Collection;
+import java.util.Objects;
 
 import static org.kohsuke.github.Previews.*;
 
@@ -27,12 +29,9 @@ public class GHBranch {
     private String protection_url;
 
     @JsonCreator
-    GHBranch(@JsonProperty("name") String name) throws Exception {
-        if (name != null) {
-            this.name = name;
-        } else {
-            throw new GHFileNotFoundException("Branch Not Found");
-        }
+    GHBranch(@JsonProperty(value = "name", required = true) String name) throws Exception {
+        Objects.requireNonNull(name);
+        this.name = name;
     }
 
     /**

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

@@ -9,8 +9,8 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 
-import static org.hamcrest.Matchers.contains;
-import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.*;
+import static org.hamcrest.core.IsInstanceOf.instanceOf;
 import static org.junit.Assert.*;
 import static org.junit.Assume.assumeFalse;
 
@@ -56,13 +56,18 @@ public class GHRepositoryTest extends AbstractGitHubWireMockTest {
         // Manually changed the returned status to 200 so dont take a new snapshot
         this.snapshotNotAllowed();
 
+        //This should *never* happen but with mocking it was discovered
         GHRepository repo = getRepository();
         try {
             GHBranch branch = repo.getBranch("test/NonExistent");
             fail();
         } catch (Exception e) {
             // I dont really love this but I wanted to get to the root wrapped cause
-            assertEquals("Branch Not Found", e.getCause().getCause().getCause().getMessage());
+            assertThat(e, instanceOf(IOException.class));
+            assertThat(e.getMessage(),
+                    equalTo("Server returned HTTP response code: 200, message: 'OK' for URL: "
+                            + mockGitHub.apiServer().baseUrl()
+                            + "/repos/github-api-test-org/github-api/branches/test%2FNonExistent"));
         }
     }