How can I store a quoted argument in a variable in bash?

Question

I have a command I want to run:

sbt "testOnly com.example.testClass"

which needs to be ran with the quotes. However, what I really want to do is be able to pass the argument in a variable, while keeping the quotes.

This does not work:

TEST_CMD="\"testOnly com.example.testClass\""
sbt $TEST_CMD

This does work:

TEST_CMD="\"testOnly com.example.testClass\""
eval sbt $TEST_CMD

I read http://mywiki.wooledge.org/BashFAQ/050 and now I understand why the first doesn't work, and I've also learned that eval can be insecure and should be avoided (this is just an internal Jenkins job, would it ever be an issue?).

Also in the article, it mentioned adding the command to an array first, so I tried:

 args=("\"testOnly com.example.testClass\"")
 sbt "${args[@]}"

but that also does not run correctly. What's the best way to do this? Is it really that bad to use eval in my case?

Maybe try: sbt "${TEST_CMD}" – jpmarinier Oct 18 '19 at 23:19 — jpmarinier, Oct 18 '19 at 23:19
@jpmarinier This still failed – Davis Mariotti Oct 18 '19 at 23:30 — Davis Mariotti, Oct 18 '19 at 23:30

score 1 · Answer 1 · answered Oct 18 '19 at 23:21

1

Quote the variable expansion rather than the assignment.

TEST_CMD="testOnly com.example.testClass"
sbt "$TEST_CMD"

answered Oct 18 '19 at 23:21

John Kugelman

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This runs as if with no quotes, so it did not work. – Davis Mariotti Oct 18 '19 at 23:30
It will give you exactly the same result as `sbt "testOnly com.example.testClass"`. – John Kugelman Oct 18 '19 at 23:50

How can I store a quoted argument in a variable in bash?

1 Answers1