Question

也就是说，当testSetupDone求值为false时会调用以下目标，在依赖链中执行目标吗？

<target name="-runTestsIfTestSetupDone" if="testSetupDone" depends="-runTests" />

Answer 1

是的，在评估条件之前执行依赖项。

来自Ant manual：

重要提示： if和unless属性仅启用或禁用它们所附加的目标。它们不控制条件目标所依赖的目标是否被执行。实际上，在目标即将执行之前，它们甚至都没有得到评估，并且它的所有前辈都已经运行了。

您也可以尝试自己：

<project>
  <target name="-runTests">
    <property name="testSetupDone" value="foo"/>
  </target>
  <target name="runTestsIfTestSetupDone" if="testSetupDone" depends="-runTests">
    <echo>Test</echo>
  </target>
</project>

我在依赖目标中设置属性testSetupDone，输出为：

Buildfile: build.xml

-runTests:

runTestsIfTestSetupDone:
     [echo] Test

BUILD SUCCESSFUL
Total time: 0 seconds

目标-runTests已执行，即使此时未设置testSetupDone，之后也会执行runTestsIfTestSetupDone，因此{/ 1}}在之前进行评估 depend（使用Ant 1.7.0）。

Answer 2

来自the docs：

Ant tries to execute the targets in the depends attribute in the order they 
appear (from left to right). Keep in mind that it is possible that a 
target can get executed earlier when an earlier target depends on it:

<target name="A"/>
<target name="B" depends="A"/>
<target name="C" depends="B"/>
<target name="D" depends="C,B,A"/>

Suppose we want to execute target D. From its depends attribute, 
you might think that first target C, then B and then A is executed. 
Wrong! C depends on B, and B depends on A, 
so first A is executed, then B, then C, and finally D.

Call-Graph:  A --> B --> C --> D

Ant目标的“if”和“depends”的评估顺序是什么？

2 个答案: