 				cacheCreator: {
 					DiskCache(rootDirectory: NSURL(fileURLWithPath: NSTemporaryDirectory(), isDirectory: true))
 				},
-				keyCreator: String.random,
-				valueCreator: String.random
+				keyCreator: String.randomReadableString,
+				valueCreator: String.randomReadableString
 			)
 		}
 	}

		describe("InMemoryCache") {
			testCache(
				cacheCreator: { InMemoryCache(cacheName: "test") },
				keyCreator: String.random,
				valueCreator: String.random
			)
		}
	}

	}
}

private let alphabet = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"

extension String {
	private static func randomReadableString() -> String {
		return self.random(15, NSCharacterSet(charactersInString: alphabet))
	}
}
