Bash script works in Python, but not in the CLI. bash: syntax error near unexpected token `('

Question

I am new to Stack Overflow and bash/sh commands. I ran into the following issue when trying to execute a shell command in 2 different ways:

1. Executing the script from the Bash CLI
2. Executing the script from a Python IDE

The script is as follows:

For /R C:\\Users\\userid\\Desktop\\my-test\\src\\api-explorer\\ %G IN (*.json) do widdershins "%G" -o "%G".md

The intent of the script is to recursively convert a number of Swagger.json files to Markdown files using a conversion tool called Widdershins.

The script runs fine when executing it from Python like this:

def convertSwaggerToMarkdown():
    cmd = 'For /R C:\\Users\\userid\\Desktop\\my-test\\src\\api-explorer\\ %G IN (*.json) do widdershins "%G" -o "%G".md
    subprocess.run(cmd, shell=True)

Where it fails, is when I try to execute the script in Bash directly. I've tried the recommendations from other users that encountered a similar error, which suggest appending either the #!/bin/bash or #!/bin/sh to the beginning of the command, but when doing this the command does not execute and also does not provide any error.

I also tried suggestions to add " " around the (*json), since this appears to be where the issue resides. Since the script executes in Python when shell=True, I'm certain there is a syntax error which I am overlooking, and also a better needed understanding of how the logic between bash and sh scripts work.

In Bash, this is what it looks like:

Syntax Error Unexpected Token

What am I missing here?

Answer 1

That script is not bash. My guess is it is PowerShell, a scripting language used in Windows that fills a similar role as Bash. The correct Bash syntax would be

for g in *.json; do
  widdershins $g -o $g.md
done

If you want the command to be recursive, best option is to use the find command, eg

find . -name \*.json -type f -exec widdershins \{\} -o \{\}.md \;

Or as an alternative, launch PowerShell to run your script instead of Bash. PowerShell is actually cross platform these days.

Answer 2

Your original command should work happily if executed directly from the cmd prompt - although the double- \ are unnecessary.

If you are executing that command as a line in a *.bat file, then each %G needs to have the % doubled %%G as G here is a metavariable. Again, the double- \ are unnecessary.