$ curl cheat.sh/
 cheat.sheets:shellcheck 
# shellcheck
# Shell script static analysis tool.

# Check a shell script:
shellcheck file.sh

# Override script's shebang:
shellcheck --shell sh|bash|ksh file.sh

# Ignore certain errors:
shellcheck --exclude SC1009 file.sh

# Ignore multiple errors:
shellcheck --exclude SC1009,SC1073 file.sh

# To disable some check, e.g. SC2034, for a statement in code
# add comment with the following line
# shellcheck disable=SC2034

 tldr:shellcheck 
# shellcheck
# Shell script static analysis tool.
# Check shell scripts for errors, usage of deprecated/insecure features, and bad practices.
# More information: <https://www.shellcheck.net>.

# Check a shell script:
shellcheck path/to/script.sh

# Check a shell script interpreting it as the specified shell dialect (overrides the shebang at the top of the script):
shellcheck --shell sh|bash|dash|ksh path/to/script.sh

# Ignore one or more error types:
shellcheck --exclude SC1009,SC1073 path/to/script.sh

# Also check any sourced shell scripts:
shellcheck --checked-sourced path/to/script.sh

# Display output in the specified format (defaults to `tty`):
shellcheck --format tty|checkstyle|diff|gcc|json|json1|quiet path/to/script.sh

# Enable one or more optional checks:
shellcheck --enable=add-default-case|avoid-nullary-conditions

# List all available optional checks that are disabled by default:
shellcheck --list-optional

$
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