How do I test a constructor in Jasmine?-CodePudding

pingPongGame.js

class PingPongGame {
    constructor(winningPoints) {
        this.playerOneScore = 0;
        this.playerTwoScore = 0;
        this.winningPoints = winningPoints;
    }

    get playerOneScore() {
        return this.playerOneScore;
    }

    set playerOneScore(newPlayerOneScore) {
        this.playerOneScore = newPlayerOneScore;
    }

    get playerTwoScore() {
        return this.playerTwoScore;
    }

    set playerTwoScore(newPlayerTwoScore) {
        this.playerTwoScore = newPlayerTwoScore;
    }

    get winningPoints() {
        return this.winningPoints;
    }

    set winningPoints(newWinningPoints) {
        this.winningPoints = newWinningPoints;
    }
}

pingPongGame.spec.js

describe("when the pingPongGame constructor is called", function () {
    it("should create a ping pong game with given arguments.", function () {
        let newPingPongGame = new PingPongGame(10);
        expect(newPingPongGame.getWinningPoints).toBe(10);
    });
});

When I run the above Jasmine test, I get the below error. I think that I might need to mock something, since it looks like there's some sort of recursion. Does anyone have suggestions on how to properly test the constructor?

when the pingPongGame constructor is called > should create a ping pong game with given arguments.
RangeError: Maximum call stack size exceeded
RangeError: Maximum call stack size exceeded
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)
    at PingPongGame.set playerOneScore [as playerOneScore] (file:///C:/Users/charl/Documents/WebDev/PingPongScorekeeper/src/pingPongGame.js:13:29)

CodePudding user response：

You're seeing a stack overflow because the names of the instance properties and the getters/setters are identical. You need to use a different name for your internal properties to use this approach. The convention is generally to prefix the name with a _ like so...

class PingPongGame {
    constructor(winningPoints) {
        //...
        this._winningPoints = winningPoints;
    }

    //...

    get winningPoints() {
        return this._winningPoints
    }

    set winningPoints(winningPoints) {
        this._winningPoints = winningPoints
    }
}