Debugging shell scripts: Syntax checking without executing

Question

Is there some option I can give to just check the syntax of a [bash] shell script to check the syntax of it, but not actually execute anything nor cause any potential damage?

Answer 1

From the bash(1) man page:

-n      Read commands but do not execute them. This may be used to check a
        shell script for syntax errors. This is ignored by interactive shells.

Answer 2

Try out http://www.shellcheck.net

$ shellcheck myscript.sh

    In myscript.sh line 590:
    for f in $*; do
    ^-- SC1009: The mentioned parser error was in this for loop.


    In myscript.sh line 617:
        if [ ! -e "$somefile".vcf ]; then
        ^-- SC1046: Couldn't find 'fi' for this 'if'.
        ^-- SC1073: Couldn't parse this if expression.


    In myscript.sh line 1026:
    done
    ^-- SC1047: Expected 'fi' matching previously mentioned 'if'.
        ^-- SC1072: Unexpected keyword/token. Fix any mentioned problems and try again.

Well, it did not tell me the 'if' was missing on line 634 but it was pretty helpful.