gradle - Gradle神秘地运行Build任务？

Question

这正在挑战我的理智。我有以下build.gradle:

import org.gradle.api.tasks.Exec
import org.apache.tools.ant.taskdefs.condition.Os

defaultTasks 'build'

// not specifying .cmd on windows will attempt to
// run the extensionless executable which will fail
ext {
  npmCommand = Os.isFamily(Os.FAMILY_WINDOWS) ? 'npm.cmd' : 'npm'
  tscCommand = Os.isFamily(Os.FAMILY_WINDOWS) ? 'tsc.cmd' : 'tsc'
}

// Get the path for the locally installed binaries
task npmBin << {
    new ByteArrayOutputStream().withStream { os ->
        exec {
            executable = npmCommand
            args = ['bin']
            standardOutput = os
        }
        ext.binPath = os.toString().trim() + File.separator
    }
}

task copyVendor(type: Copy) {
  from 'node_modules/systemjs/dist/system.src.js',
       'node_modules/angular2/bundles/angular2.dev.js',
       'node_modules/angular2/bundles/http.dev.js'
  into 'build/app/scripts/vendor'
}

task copyNonTS(type: Copy) {
  from('app') {
    exclude '**/*.ts', '**/*.js.map'
  }
    filter { line -> line.replaceAll('(node_modules\\/systemjs\\/dist)|(node_modules\\/angular2\\/bundles)', 'app/scripts/vendor') }
  into 'build/app'
}

// Install packages from package.json
task npm(type: Exec) {
    description = "Grab NodeJS dependencies (from package.json)"
    commandLine = [npmCommand, "install"]
    inputs.file "package.json"
    outputs.dir "node_modules"

    tasks.npmBin.execute()
}

task cleanDev(type: Delete) {
    outputs.upToDateWhen { false }
  delete fileTree(dir: 'app', include: ['**/*.js', '**/*.js.map'])
}

task delOutput(type: Delete) {
    outputs.upToDateWhen { false }
    println "DELETING"
    delete 'build/'
}

task clean(type: Delete) {
    outputs.upToDateWhen { false }
    cleanDev.execute()
    delOutput.execute()
}

task build(dependsOn: 'npm', type: Exec) {
    println "BUILDING"
    if (file(new File("${npmBin.binPath}${tscCommand}")).isFile()) {
        // runs non-globally installed tsc from node_modules
        commandLine "${npmBin.binPath}${tscCommand}"
    } else {
        // runs globally installed tsc
        commandLine = [tscCommand]
    }
  copyVendor.execute()
  copyNonTS.execute()
}

以某种方式，当我运行 gradle delOutput时，我得到以下输出:

DELETING
BUILDING
:delOutput

BUILD SUCCESSFUL

Total time: 2.012 secs

为什么当我运行这个看似很小的，原子性的，无依赖性的任务时，我的构建任务仍在运行？它删除了我的构建文件夹，然后立即要求再次执行构建任务(如输出“BUILDING”所示)。

这里发生了什么事？

编辑:

这个 forum post同意这里所说的。但是，似乎如果我有一个 type: Exec任务，那么我必须在配置阶段指定 commandLine，这样做似乎总是执行命令，而不管我是否实际要运行该任务。如何仅在运行任务时运行 commandLine？

Answer 1

task hello << {
    println 'Hello world!'
}

是短手

task hello {
    doLast {
        println 'Hello world!'
    }
}

如果您没有 doLast，则该任务将在配置阶段运行，而不是在您显式调用它时运行。

将您的任务定义从 task build(){更改为 task build()<<{
编辑以进行编辑:

这样的事情对您有用吗？

task hello {

    def commandline = 'something' //in the config phase

    doLast {
        println 'Executing!' //in the exec phase
    }
}