How do I syntax check a Bash script without running it?

Bonzo_13523 0
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Is it possible to check a bash script syntax without executing it?

Using Perl, I can run perl -c 'script name'. Is there any equivalent command for bash scripts?

gnu syntax unix linux bash
10 Answers
bash -n scriptname

Perhaps an obvious caveat: this validates syntax but won't check if your bash script tries to execute a command that isn't in your path, like ech hello instead of echo hello.

andy_61520 
sh  -n   script-name

Run this. If there are any syntax errors in the script, then it returns the same error message. If there are no errors, then it comes out without giving any message. You can check immediately by using echo $?, which will return 0 confirming successful without any mistake.

It worked for me well. I ran on Linux OS, Bash Shell.

user_6000320

For only validating syntax:

shellcheck [programPath]

For running the program only if syntax passes, so debugging both syntax and execution:

shellproof [programPath]

user_46206170

Bash shell scripts will run a syntax check if you enable syntax checking with

set -o noexec

if you want to turn off syntax checking

set +o noexec
user_167835890

If you need in a variable the validity of all the files in a directory (git pre-commit hook, build lint script), you can catch the stderr output of the "sh -n" or "bash -n" commands (see other answers) in a variable, and have a "if/else" based on that

bashErrLines=$(find bin/ -type f -name '*.sh' -exec sh -n {} \;  2>&1 > /dev/null)
  if [ "$bashErrLines" != "" ]; then 
   # at least one sh file in the bin dir has a syntax error
   echo $bashErrLines; 
   exit; 
  fi

Change "sh" with "bash" depending on your needs

user_4150320
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