Question

I've got the test.groovy script below, but when I run it, I get the following output.

groovy test.groovy
set color to good
set color to unstable
unstable

Why am I seeing 'set color to good'?

Line 13 states

case "SUCCESS" :

But buildStatus is "UNSTABLE"

I've never used a switch statement before in groovy, so could be missing something pretty basic.

test.groovy

def print_arg(def arg){
    buildStatus = "UNSTABLE"
    previousBuild = "FAILURE"
    // println "$arg"
    switch(buildStatus) {
        case { it != "SUCCESS" } :
            switch(previousBuild) {
                case "SUCCESS" :
                    println "set color to danger"
                    color = 'danger'
                    break;
            }
        case "SUCCESS" :
            switch(previousBuild) {
                case { it != "SUCCESS"} :
                    println "set color to good"
                    color = 'good'
                    break;
            }
        case "UNSTABLE" :
            println "set color to unstable"
            color = 'unstable'
            break;
    }
println "$color"
}

print_arg()

Answer 1

您看到set color to good是因为在第一种情况的末尾没有break语句。

第一种情况与{ it != "SUCCESS" }匹配，嵌套开关不匹配。然后，由于之前没有break，执行进入第二种情况。第二种情况会执行，并且也没有break，因此会进入第三种情况。

因此，switch的运行与其预期的一样。

我不确定您的初衷是什么，并且嵌套switch操作并不会增加代码的可读性，但是我会这样放置您的代码：

    switch(buildStatus) {
        case { it != "SUCCESS" } :
            switch(previousBuild) {
                case "SUCCESS" :
                    println "set color to danger"
                    color = 'danger'
                    break;
            }
            break // << ADD THIS
        case "SUCCESS" :
            switch(previousBuild) {
                case { it != "SUCCESS"} :
                    println "set color to good"
                    color = 'good'
                    break;
            }
            break // << ADD THIS
        case "UNSTABLE" :
            println "set color to unstable"
            color = 'unstable'
            break;
    }

Groovy switch not behaving as expected

1 个答案: