Add support for faking an error for throwing functions in ReturningFu…

…nctionMock (#2)

Mokka/Sources/FunctionMock/FunctionMock.swift

@@ -64,7 +64,7 @@ public class FunctionMock<Args> {
  public var argument: Args? { return arguments } // syntactic alternative for single-arg methods
 
  private var stubBlock: ((Args) -> Void)?
- private var error: Error?
+ internal var error: Error?
 
  /// Creates a new instance of a function mock with the specified name.
  ///

Mokka/Sources/FunctionMock/ReturningFunctionMock.swift

@@ -59,19 +59,28 @@ public class ReturningFunctionMock<Args, ReturnValue>: FunctionMock<Args> {
  ///
  /// - parameters:
  /// - args: The arguments that the mocked function has been called with.
+ /// - returns: The return value configured via `returns(...)`.
  public func recordCallAndReturn(_ args: Args) -> ReturnValue {
  recordCall(args)
-
- // stub return value
- guard let stub = stubs.first(where: { $0.shouldHandle(args) }) else {
- if let returnValue = defaultReturnValue {
- return returnValue
- }
- preconditionFailure("No return value for \(name ?? "function")")
+ return getReturnValue(args: args)
+ }
+
+ /// Record a call of the mocked function and potentially throw an error, if configured.
+ ///
+ /// - parameters:
+ /// - args: The arguments that the mocked function has been called with.
+ /// - returns: The return value configured via `returns(...)`.
+ /// - throws: The error that has been configured via `throws(_:)`, if any.
+ public func recordCallAndReturnOrThrow(_ args: Args) throws -> ReturnValue {
+ recordCall(args)
+
+ if let error = error {
+ throw error
+ } else {
+ return getReturnValue(args: args)
  }
-
- return stub.handle(args)
  }
+
 
  // MARK: - Stubbing
 
@@ -113,6 +122,20 @@ public class ReturningFunctionMock<Args, ReturnValue>: FunctionMock<Args> {
  stubs.append(stub)
  }
 
+ // MARK: - Private
+
+ /// Get the stubbed return value for the specified arguments.
+ private func getReturnValue(args: Args) -> ReturnValue {
+ guard let stub = stubs.first(where: { $0.shouldHandle(args) }) else {
+ if let returnValue = defaultReturnValue {
+ return returnValue
+ }
+ preconditionFailure("No return value for \(name ?? "function")")
+ }
+
+ return stub.handle(args)
+ }
+
  // MARK: - FunctionStub
 
  /// Used internally to represent a static or dynamic stubbed return

Mokka/Tests/FunctionMock/ReturningFunctionMockTests.swift

@@ -142,6 +142,47 @@ class ReturningFunctionMockTests: XCTestCase {
  XCTAssertEqual(result, 42)
  }
 
+ // MARK: Throwing
+
+ func testDoesNotThrowErrorIfNotExplicitlyConfigured() {
+ sut.returns(42)
+ XCTAssertNoThrow(try sut.recordCallAndReturnOrThrow("foo"))
+ }
+
+ func testThrowsErrorAfterSettingError() {
+ sut.throws(TestError.errorOne)
+ XCTAssertThrowsError(try sut.recordCallAndReturnOrThrow("foo")) { error in
+ XCTAssert(error is TestError, "Unexpected error type thrown")
+ XCTAssertEqual(error as! TestError, TestError.errorOne)
+ }
+ }
+
+ func testRecordCallAndReturnOrThrowRecordsCallsWhenNotThrowing() {
+ sut.returns(42)
+ XCTAssertNoThrow(try sut.recordCallAndReturnOrThrow("foo"))
+ XCTAssertNoThrow(try sut.recordCallAndReturnOrThrow("bar"))
+ XCTAssertEqual(sut.callCount, 2)
+ }
+
+ func testRecordCallAndReturnOrThrowCapturesArgumentsWhenNotThrowing() {
+ sut.returns(42)
+ XCTAssertNoThrow(try sut.recordCallAndReturnOrThrow("foo"))
+ XCTAssertEqual(sut.argument, "foo")
+ }
+
+ func testRecordCallAndReturnOrThrowRecordsCallsWhenThrowing() {
+ sut.throws(TestError.errorOne)
+ XCTAssertThrowsError(try sut.recordCallAndReturnOrThrow("foo"))
+ XCTAssertThrowsError(try sut.recordCallAndReturnOrThrow("bar"))
+ XCTAssertEqual(sut.callCount, 2)
+ }
+
+ func testRecordCallAndReturnOrThrowCapturesArgumentsWhenThrowing() {
+ sut.throws(TestError.errorOne)
+ XCTAssertThrowsError(try sut.recordCallAndReturnOrThrow("foo"))
+ XCTAssertEqual(sut.argument, "foo")
+ }
+
  // MARK: Reset
 
  func testCallCountIsZeroAfterReset() {