Gradle 构建期间出现 NPE?

Gradle NPE during build?

我在尝试构建我的项目时收到 NullPointerException。我目前在顶层将我的依赖项声明为 properties,然后在子模块中引用(如下所示):

错误:

A problem occurred evaluating project ':myProject'.
> java.lang.NullPointerException (no error message)

Caused by: java.lang.NullPointerException
        at org.gradle.util.GUtil.flatten(GUtil.java:69)
        at org.gradle.util.GUtil.flatten(GUtil.java:66)
        at org.gradle.util.GUtil.collectionize(GUtil.java:93)
        at org.gradle.util.GUtil$collectionize.call(Unknown Source)
        at org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler.methodMissing(DefaultDependencyHandler.groovy:
        at org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler.invokeMethod(DefaultDependencyHandler.groovy)  

顶级声明:

ext.libraries = [

   junit: 'junit:junit:4.12',
   mockito: 'org.mockito:mockito-all:1.9.5'

]

在子模块中引用 属性:

testCompile([
   libraries.junit,
   libraries.mockito

])

我在子模块的 testCompile([ 行收到错误。可能是什么原因造成的?

以下脚本可与 gradle 2.8 一起正常工作:

apply plugin: 'java'

ext.libraries = [

   junit: 'junit:junit:4.12',
   mockito: 'org.mockito:mockito-all:1.9.5'

]

repositories {
  mavenCentral()
}

dependencies {
  testCompile(
    [
      libraries.junit,
      libraries.mockito
    ]
  )
}

看看这里的demo