linux - Bash 函数忽略 set -e

Question

如何将函数作为“测试命令”运行并在失败时执行操作，同时仍然在发生错误时立即中止该函数？ 考虑以下脚本

#!/bin/bash -e

function foo() {
   echo Entering foo
   false
   echo Should not reach this line
}

foo || echo I want to see this line on failure in foo
foo

我得到的输出是

Entering foo
Should not reach this line
Entering foo

虽然我想得到

Entering foo
I want to see this line on failure in foo
Entering foo

我想我正在寻找的是一种将函数标记为未测试命令的方法。根据 bash 手册页

 -e errexit
         Exit immediately if any untested command fails in non-interactive
         mode.  The exit status of a command is considered to be explicitly
         tested if the command is part of the list used to control an if,
         elif, while, or until; if the command is the left hand operand of
         an “&&” or “||” operator; or if the command is a pipeline preceded
         by the ! operator.  If a shell function is executed and its exit
         status is explicitly tested, all commands of the function are con‐
         sidered to be tested as well.

编辑 预期的输出是错误的。为清楚起见对其进行了编辑

Answer 1

set -e 在第一次调用 foo 时被禁用，因为它位于 || 的左侧。

此外，你永远不会看到输出的 I want to see this ... 字符串，除非 foo 中的最后一个 echo 不知何故失败(是 foo 中的最后一个 echo 决定函数的退出状态)。

foo() {
    echo Entering foo
    false && echo Should not reach this line
}

foo || echo I want to see this line on failure in foo
foo

以上输出(带或不带set -x)

Entering foo
I want to see this line on failure in foo
Entering foo

现在 false 是 foo 中最后执行的语句。