为什么Linux命令CP在CLI和脚本中的行为有所不同？

cp <some_dir>/*.{v,sv,svh} .

有用.但是当我将它放到具有完全相同行的脚本时,CP命令会失败并显示日志：

cp: cannot stat `../../mytest/spiTest/*.{v,svh}': No such file or directory

这是怎么回事？

PS：我使用bash作为shell.

这是我的脚本：

#!/bin/bash
rdir=../../mytest/spiTest
f1="$rdir/bench.lst"
f2="$rdir/cphex" #the script to copy rom data
f3="$rdir/make*" #makefile scripts
f4="$rdir/*.hex" #rom files
f5="$rdir/*.{v,svh}" #testbench files
echo 'Copying files...'
cp $f1 $f2 $f3 $f4 .
cp $f5 .

我把第一行更改为

#!/bin/bash -vx

并再次运行此脚本,我得到：

#!/bin/bash -vx

rdir=../../mytest/spiTest
+ rdir=../../mytest/spiTest
f1="$rdir/bench.lst"
+ f1=../../mytest/spiTest/bench.lst
f2="$rdir/cphex" #the script to copy rom data
+ f2=../../mytest/spiTest/cphex
f3="$rdir/make*" #makefile scripts
+ f3='../../mytest/spiTest/make*'
f4="$rdir/*.hex" #rom files
+ f4='../../mytest/spiTest/*.hex'
f5="$rdir/*.{v,svh}" #testbench files
+ f5='../../mytest/spiTest/*.{v,svh}'

echo 'Copying files...'
+ echo 'Copying files...'
Copying files...
cp $f1 $f2 $f3 $f4 .
+ cp ../../mytest/spiTest/bench.lst ../../mytest/spiTest/cphex ../../mytest/spiTest/makefile ../../mytest/spiTest/makefile.defines ../../mytest/spiTest/rom.hex ../../mytest/spiTest/rom_if.hex .
cp $f5 .
+ cp '../../mytest/spiTest/*.{v,svh}' .
cp: cannot stat `../../mytest/spiTest/*.{v,svh}': No such file or directory