Make PullRequestFile#patch an Option[String]

github4s/shared/src/main/scala/github4s/free/domain/PullRequest.scala

@@ -50,7 +50,7 @@ case class PullRequestFile(
     blob_url: String,
     raw_url: String,
     contents_url: String,
-    patch: String,
+    patch: Option[String],
     previous_filename: Option[String])
 sealed trait CreatePullRequest {
   def head: String

github4s/shared/src/test/scala/github4s/integration/GHPullRequestsSpec.scala

@@ -71,6 +71,18 @@ trait GHPullRequestsSpec[T] extends BaseIntegrationSpec[T] {
     })
   }
 
+  "PullRequests >> ListFiles" should "return a right response when a valid repo is provided and not all files have 'patch'" in {
+    val response =
+      Github(None).pullRequests
+        .listFiles("scala", "scala", 4877)
+        .execFuture[T](headerUserAgent)
+
+    testFutureIsRight[List[PullRequestFile]](response, { r =>
+      r.result.nonEmpty shouldBe true
+      r.statusCode shouldBe okStatusCode
+    })
+  }
+
   it should "return error when an invalid repo name is passed" in {
     val response =
       Github(accessToken).pullRequests

github4s/shared/src/test/scala/github4s/utils/TestData.scala

@@ -208,7 +208,7 @@ trait TestData extends DummyGithubUrls {
     blob_url = githubApiUrl,
     raw_url = githubApiUrl,
     contents_url = githubApiUrl,
-    patch = "",
+    patch = None,
     previous_filename = None
   )