bash - Bash脚本: How to ensure script exits on any error in function called with an “or” (||) condition?

Question

这是一个示例脚本:

#!/bin/bash
set -euo pipefail

function_test () {
        echo "Everything still ok."
        thisdoesnotexist
        echo "It continues running..."
}

function_test || { echo "Error occured in function_test."; exit 1; }

我希望此脚本在“thisdoesnotexist”上退出，因为set -e已激活。错误消息“在function_test中发生错误”。应该出现，或者至少应该退出脚本。相反，脚本继续运行:

$ ./testscript.sh 
Everything still ok.
./testscript.sh: Zeile 6: thisdoesnotexist: Kommando nicht gefunden.
It continues running...

我认为这是因为根据 set的手册，我在“或”(||)上下文中使用该函数:

Exit immediately [...] unless the command that fails is part of an until or while loop, part of an if statement, part of a && or || list, [...]

在脚本中处理此问题的最佳方法是什么？我删除了“||”并使用了这样的错误陷阱:

#!/bin/bash
set -Eeuo pipefail

errorhandler () {
        echo "Errorhandler called. Exiting."
        exit 1
}

trap "errorhandler" ERR

function_test () {
        echo "Everything still ok."
        thisdoesnotexist
        echo "It continues running..."
}

function_test

哪个有效:

$ ./testscript.sh 
Everything still ok.
./testscript.sh: Zeile 13: thisdoesnotexist: Kommando nicht gefunden.
Errorhandler called. Exiting.

在这种情况下，尽管似乎无法输出用户友好的消息(例如，该消息包含脚本中发生错误的步骤)。为此，我至少必须将函数名称传递给错误陷阱。我尝试过，但是没有找到有效的解决方案。

您有更好的建议吗？

Answer 1

如果您想在出现错误的情况下做一些事情，并且知道某些地方可能出了问题，那么:

function_test () {
        echo "Everything still ok."
        thisdoesnotexist || {
          # handle thisdoesnotexist failure
          Echo "thisdoesnotexist failed" >&2
          exit 1
        }
        echo "It continues running..."
        if ! thisdoesnotexisteither; then
          # Handle fail for thisdoesnotexisteither
          Echo "thisdoesnotexisteither failed" >&2
          exit 1
        fi
}

现在，为了测试Bash中的错误处理，您可以使用此智能错误处理功能:

#!/usr/bin/env bash

# Generate an error
# @Params
# $1: Numeric error return code
# ${2[@]}: Messages
# @Output
# &1: Generic success message
# &2: Generic or passed error messages
# @Return
# $?: Intended return code
erroring() {
  local rc=1
  if [ "$#" -gt 0 ]; then
    rc="$1"
    shift
    if printf '%d' "$rc" >/dev/null 2>&1; then
      # rc is an integer
      if [ "$rc" -gt 0 ]; then
        printf $"Intended failure with code: %d\\n" "$rc" >&2
        if [ "$#" -gt 0 ]; then
          # There are supplied messages to print"
          printf $"%d messages:\\n" "$#" >&2
          printf '%q\n' "$@" >&2
        fi
      else
        echo $"Intended success"
      fi
    else
      printf $"Invalid non-numeric return code parameter: %q\\n" "$rc" >&2
      rc=7
    fi
  else
    erroring "$rc"
  fi
  return "$rc"
}