Only the line containing the "Usage:" identifier is parsed on bash 4.4.12

[jcooley]

Only the line containing the "Usage:" identifier is parsed on Debian GNU/Linux 9 (stretch)

GNU bash, version 4.4.12(1)-release (x86_64-pc-linux-gnu)

It works fine on 4.4.20 (Ubuntu 18.04.4).

I was also seeing the following on 4.4.12

goroutine 1 [running]:
main.main()
    /tmp/docopts_v0.6.3-rc2.5349/docopts.go:458 +0xfc7
docopt_print_ARGS -G => ARGS_*

but I fixed this by pulling the first line of usage back up to the e.g.

# Usage: command1 arg1 arg2

and not

# Usage: 
#  script command1 arg1 arg2

Either will work on 4.4.20. I am using

PATH=../..:$PATH
source ~/docopts.sh --auto -G "$@"

The workaround is to delete all usage lines before the one that is required at the time.

[Sylvain303]

Hi @jcooley

Sorry for the delay, I'm a bit away from keyboard. :sun_with_face:

Could you attach the script that fires up that bug? And how you run it.

Could you give me the docopts version please, too.

Also please note that the docopt syntax must in include the progname before the argument: prog arg1 arg2 etc...

# Usage: command1 arg1 arg2

Does the progname is missing here?

Regards, Sylvain.

[jcooley]

Hi Sylvain,

Just back from a break too. I'm using the latest docopts using ./get_docopts.sh

I can reproduce it with the debian 9 docker image

 $ docker run --rm -it -v /src/docopts:/docopts debian:9 /bin/bash
 # cd /docopts/
 # apt update
 # apt install wget
 # ./get_docopts.sh

and when I run the quick_example.sh I see

panic: no fields found in usage (perhaps a spacing error).

goroutine 1 [running]:
main.main()
        /tmp/docopts_v0.6.3-rc2.5349/docopts.go:458 +0xfc7
root@979777acbdfc:/docopts/examples#

but I can fix it by moving the command up to the Usage: line

-# Usage:
-#  quick_example.sh tcp <host> <port> [--timeout=<seconds>]
+# Usage: quick_example.sh tcp <host> <port> [--timeout=<seconds>]

If I can provide more detail let me know.

Thanks, James

[Sylvain303]

Hi @jcooley,

Thanks reporting this issue.

I ran your commands on Linux xubuntu 20.04, and I did reproduce the error.

It is the same error as https://github.com/docopt/docopts/issues/47#issuecomment-669899049. It's related to a change I made in the docopts.sh helper using a gawk regexp feature to extract the help string. awk command is not always gawk it's some time mawk which has lower feature on regexp syntax.

I commited a fix:

https://github.com/docopt/docopts/commit/c21151315bea2852ef3250c70a52352c9cd0d6eb

I reran the following commands:

cd /tmp
# a fresh new master copy
git clone git@github.com:docopt/docopts.git
docker run --rm -it -v /tmp/docopts:/docopts debian:9 /bin/bash
# inside the container
apt update -y
# file and wget are required in order to run ./get_docopts.sh 
apt install -y vim git tree file wget
cd /docopts/
./get_docopts.sh
cd ./examples/

Now is seems OK.

./quick_example.sh 
error: 
Usage:
 quick_example.sh tcp <host> <port> [--timeout=<seconds>]
 quick_example.sh serial <port> [--baud=9600] [--timeout=<seconds>]
 quick_example.sh -h | --help | --version

Unit testing:

cd ../tests/
git clone https://github.com/bats-core/bats-core.git
./bats-core/install.sh /usr/local

running tests

bats ./docopts.bats 
 ✓ docopt_get_help_string
 ✓ docopt_get_help_string with Options (this test may fail if bats fix their issue #224)
 ✓ docopt_get_help_string with with 2 Usage:
 ✓ docopt_get_values
 ✓ docopt_get_eval_array
 ✓ docopt_get_raw_value
 ✓ docopt_print_ARGS
 ✓ docopt_print_ARGS -G
 ✓ docopt_get_version_string from $0
 ✓ bash strict mode docopt_print_ARGS

10 tests, 0 failures

It should be ok. I close this issue, reopen if some problem persists.

[jcooley]

Thanks @Sylvain303, I was back on the server during the week and the fix worked great.