Bash test command to check files exists not works as expected

Čamo

4/24/24, 7:07 PM

I have a simple bash script. I need to check if file exists and then do some actions related to check result. Script looks like:

#!/bin/bash

productionPackageJsonPath=/var/www/portaldev/current/package.jsonxxx
productionNodeModulesPath=/var/www/portaldev/current/node_modules

hasPackageJsonFile=$(test -f productionPackageJsonPath)
hasDiff=""

if [ "$hasPackageJsonFile" == "true"  ]
then
    echo "aaaaaaaaaaaaaaaaaaaa"
    hasDiff=$(diff ${productionPackageJsonPath} package.json)
else
    echo "bbbbbbbbbbbbbbbbbbb"
fi

This should return false cause package.jsonxxx does not exist. But I am getting always true or i dont know what. But console always write echo "aaaaaaaaaaaaaaaaaaa"

Can somebody tell me please what am I doing wrong? Thnxsm.

107

2 + 2

command-line

bash

scripts

Rinzwind

4/24/24, 7:11 PM

where is the `-f`?

Čamo

4/24/24, 7:18 PM

$(test -f productionPackageJsonPath)

Score:1

Ubuntu

Čamo

4/24/24, 7:45 PM

So my solution is:

productionPackageJsonPath=/var/www/portaldev/current/package.json

if [ -f $productionPackageJsonPath ]
then
    echo "aaaaaaaaaaaaaaaaaaaa"
    hasDiff=$(diff ${productionPackageJsonPath} package.json)
else
    echo "bbbbbbbbbbbbbbbbbbb"
    hasDiff=""
fi

+ 0

Score:1

Ubuntu

user unknown

4/24/24, 8:16 PM

hasPackageJsonFile=$(test -f productionPackageJsonPath)

Now the output of the command test -f productionPackageJsonPath is assigned to hasPackageJsonFile. This variable will always be empty, since $(...) captures the output of programs, not results.

+ 2

Čamo

4/29/24, 12:16 AM

Thanks, but how to assign a result to the variable? Obviously I need result in variable.

user unknown

4/29/24, 2:02 AM

`lastresult=$?` stores the error of the last command (0 := no error, success) in a variable, but you might as well (most of the time) use an if around the test directly, instead of an intermediate variable.

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