w: /home/travis/build/[secure]/Fuel/fuel/src/main/kotlin/com/github/[secure]/fuel/core/requests/CancellableRequest.kt: (39, 38): Unnecessary safe call on a non-null receiver of type InterruptCallback /* = (Request) -> Unit */
w: /home/travis/build/[secure]/Fuel/fuel/src/main/kotlin/com/github/[secure]/fuel/core/requests/RequestTask.kt: (13, 72): Elvis operator (?:) always returns the left operand of non-nullable type InterruptCallback /* = (Request) -> Unit */
w: /home/travis/build/[secure]/Fuel/fuel/src/main/kotlin/com/github/[secure]/fuel/core/requests/SuspendableRequest.kt: (12, 72): Elvis operator (?:) always returns the left operand of non-nullable type InterruptCallback /* = (Request) -> Unit */