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Full Discussion: Can I do this without eval? (zsh)
Top Forums Shell Programming and Scripting Can I do this without eval? (zsh) Post 302990299 by rovf on Tuesday 24th of January 2017 12:07:44 PM
Old 01-24-2017
Quote:
Originally Posted by Corona688
So this takes a single $op, such as "-z", and a single $arg, which is supposed to be a literal value? Feed them into the test external to test them outside the shell:

Code:
if test "$op" "$arg"
then
...
fi

test won't support the full extended zsh syntax, just the basic bourne. It won't evaluate any shell code or variables whatsoever and will never make your program quit from syntax error. If someone tries inserting multiple things into $op to be tricky, it just won't work.
op is safe, because I run into this code only if op matches the glob pattern -[a-zA-Z].

I like your idea, because of its simplicity. Its main drawback is that, at least according to my manpage of test, it does not work with the -N file test operator (true if file exists and its access time is not newer than its modification time), so I have to think about how important this is for me. It also doen't work with -o, which is not really a problem though, because this is not a file test.

Currently, I'm guarding the argument with

Code:
if [[ "${arg//['\\]/}" == $arg ]]
then
  # we are safe here
else 
  # danger!
fi

which also has the nasty side effect, that the quoting upsets the syntax highlighter of my text editor (IntelliJ IDEA) in the same way as it upsets syntax highlighting in this forum....
 

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LEARN ABOUT CENTOS

dh_auto_test

DH_AUTO_TEST(1) 						     Debhelper							   DH_AUTO_TEST(1)

NAME

       dh_auto_test - automatically runs a package's test suites

SYNOPSIS

       dh_auto_test [buildsystemoptions] [debhelperoptions] [--params]

DESCRIPTION

       dh_auto_test is a debhelper program that tries to automatically run a package's test suite. It does so by running the appropriate command
       for the build system it detects the package uses. For example, if there's a Makefile and it contains a test or check target, then this is
       done by running make (or MAKE, if the environment variable is set). If the test suite fails, the command will exit nonzero. If there's no
       test suite, it will exit zero without doing anything.

       This is intended to work for about 90% of packages with a test suite. If it doesn't work, you're encouraged to skip using dh_auto_test at
       all, and just run the test suite manually.

OPTIONS

       See "BUILD SYSTEM OPTIONS" in debhelper(7) for a list of common build system selection and control options.

       -- params
	   Pass params to the program that is run, after the parameters that dh_auto_test usually passes.

NOTES

       If the DEB_BUILD_OPTIONS environment variable contains nocheck, no tests will be performed.

SEE ALSO

       debhelper(7)

       This program is a part of debhelper.

AUTHOR

       Joey Hess <joeyh@debian.org>

11.1.6ubuntu2							    2018-05-10							   DH_AUTO_TEST(1)
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