总的来说，我对 ScalaMock 和模拟都是新手。我正在尝试测试一个方法，该方法调用另一个（模拟）类中的方法，然后在返回的对象上调用一个方法。
详细资料：
所以我正在使用 ScalaTest，这个测试涉及五个类......
我正在测试的子指令
class SubInstruction(label: String, val result: Int, val op1: Int, val op2: Int) extends Instruction(label, "sub") {
override def execute(m: Machine) {
val value1 = m.regs(op1)
val value2 = m.regs(op2)
m.regs(result) = value1 - value2
}
}
object SubInstruction {
def apply(label: String, result: Int, op1: Int, op2: Int) =
new SubInstruction(label, result, op1, op2)
}
必须为测试模拟的机器
case class Machine(labels: Labels, prog: Vector[Instruction]) {
private final val NUMBEROFREGISTERS = 32
val regs: Registers = new Registers(NUMBEROFREGISTERS)
override def toString(): String = {
prog.foldLeft("")(_ + _)
}
def execute(start: Int) =
start.until(prog.length).foreach(x => prog(x) execute this)
}
object Machine extends App {
if (args.length == 0) {
println("Machine: args should be sml code file to execute")
} else {
println("SML interpreter - Scala version")
val m = Translator(args(0)).readAndTranslate(new Machine(Labels(), Vector()))
println("Here is the program; it has " + m.prog.size + " instructions.")
println(m)
println("Beginning program execution.")
m.execute(0)
println("Ending program execution.")
println("Values of registers at program termination:")
println(m.regs + ".")
}
}
构造机器对象所需的寄存器
case class Registers(size: Int) {
val registers: Array[Int] = new Array(size)
override def toString(): String =
registers.mkString(" ")
def update(k: Int, v: Int) = registers(k) = v
def apply(k: Int) = registers(k)
}
我作为原始 Machine 类创建的 MockableMachine 没有空的构造函数，因此（据我了解）不能被模拟
class MockableMachine extends Machine(Labels(), Vector()){
}
最后是我的测试类 SubInstructionTest 编译但抛出下面的异常。
class SubInstructionTest extends FlatSpec with MockFactory with Matchers {
val label1 = "f0"
val result1 = 25
val op1_1 = 24
val op2_1 = 20
val sub1 = SubInstruction(label1, result1, op1_1, op2_1)
"A SubInstruction" should "retrieve the operands from the correct registers in the given machine " +
"when execute(m: Machine) is called, and perform the operation saving the " +
"result in the correct register." in {
val mockMachine = mock[MockableMachine]
inSequence {
(mockMachine.regs.apply _).expects(op1_1).returning(50)
(mockMachine.regs.apply _).expects(op2_1).returning(16)
(mockMachine.regs.update _).expects(result1, 34)
}
sub1.execute(mockMachine)
}
}
抛出：
java.lang.NoSuchMethodException: Registers.mock$apply$0()
-
我一直在寻找一种简单的方法来模拟这门课几个小时，但一无所获。目前我已经确定了下面详述的解决方法，但我的印象是，模拟会为测试我的 SubInstruction 类的问题提供一个不那么复杂的解决方案。
解决方法：
删除 MockableMachine 类并创建一个 CustomMachine 类，该类扩展 Machine 并用构造时提供的 mockedRegisters 替换寄存器值。
class CustomMachine (mockedRegister: Registers) extends Machine(Labels(), Vector()) {
override
val regs: Registers = mockedRegister
}
我作为原始创建的 MockableRegisters 类没有空构造函数，因此（据我了解）不能被模拟
class MockableRegisters extends Registers(32) {
}
和以稍微不同的方式编写的 SubInstructionTest 类
class SubInstructionTest extends FlatSpec with MockFactory with Matchers {
val label1 = "f0"
val result1 = 25
val op1_1 = 24
val op2_1 = 20
val sub1 = SubInstruction(label1, result1, op1_1, op2_1)
"A SubInstruction" should "retrieve the operands from the correct registers in the given machine " +
"when execute(m: Machine) is called, and perform the operation saving the " +
"result in the correct register." in {
val mockRegisters = mock[MockableRegisters]
val machine = new CustomMachine(mockRegisters)
inSequence {
(mockRegisters.apply _).expects(op1_1).returning(50)
(mockRegisters.apply _).expects(op2_1).returning(16)
(mockRegisters.update _).expects(result1, 34)
}
sub1.execute(machine)
}
}
如前所述，这对我来说感觉像是一种解决方法，难道没有更简单的方法可以做到这一点（可能类似于我最初的尝试）？
我刚刚包含了提出问题的基本代码，但是您可以在我的GitHub 帐户上找到完整的代码。