Bitbucket Pipelines中YAML锚点内联Bash脚本语法错误求助

问题 #

在Bitbucket Pipeline中编写了如下YAML锚点配置：

npm_audit: &npm_audit
    echo "Running npm audit..."
    npm_audit_output=$(npm audit --audit-level=critical)
    if [ $? -ne 0 ]; then
    echo "Critical vulnerabilities found. They must be fixed manually:"
    exit 1
    fi
    npm_audit_output=$(npm audit)
    if [ $? -ne 0 ]; then
    echo "Non-critical vulnerabilities found."
    echo "$npm_audit_output"
    echo "Attempting to fix..."
    npm audit fix
    else
    echo "No vulnerabilities found."
    fi

通过以下方式调用该锚点：

- step:
      ...
      script:
        - *npm_audit

Bitbucket返回错误：

+ echo "Running npm audit..." npm_audit_output=$(npm audit --audit-level=critical) if [ $? -ne 0 ]; then echo "Critical vulnerabilities found. They must be fixed manually:" exit 1 fi npm_audit_output=$(npm audit) if [ $? -ne 0 ]; then echo "Non-critical vulnerabilities found." echo "$npm_audit_output" echo "Attempting to fix..." npm audit fix else echo "No vulnerabilities found." fi
bash: bashScript5261110360543614450.sh: line 5: syntax error near unexpected token `then'

ShellCheck检测该Bash脚本无异常，请问为何会出现语法错误？为何整个脚本被回显而非指定字符串？

原因与解决方法 #

核心问题：YAML锚点类型不匹配 #

Bitbucket Pipeline的script字段要求每一项是单个字符串形式的Shell命令，但你定义的锚点&npm_audit是YAML序列（多行命令集合），直接用*npm_audit引用时，YAML会把整个序列合并成单个字符串传入Shell，导致所有命令被拼接成一行执行，既触发语法错误，又让echo把后续所有内容当成参数输出。

解决办法 #

将锚点定义为多行字符串，用|保留换行符，让Shell能正确识别每条命令：

npm_audit: &npm_audit |
    echo "Running npm audit..."
    npm_audit_output=$(npm audit --audit-level=critical)
    if [ $? -ne 0 ]; then
      echo "Critical vulnerabilities found. They must be fixed manually:"
      exit 1
    fi
    npm_audit_output=$(npm audit)
    if [ $? -ne 0 ]; then
      echo "Non-critical vulnerabilities found."
      echo "$npm_audit_output"
      echo "Attempting to fix..."
      npm audit fix
    else
      echo "No vulnerabilities found."
    fi

调用方式不变，此时YAML会把锚点内容作为带换行的单个字符串传给script，Shell会按换行分割成多条命令执行，语法错误和回显问题都会解决。

内容的提问来源于stack exchange，提问作者alex