SC2231 – ShellCheck Wiki

Quote expansions in this `for` loop glob to prevent wordsplitting, e.g. `"$dir"/*.txt` .

Problematic code:

for file in $dir/*.txt
do
  echo "Found $file"
done

Correct code:

for file in "$dir"/*.txt
do
  echo "Found $file"
done

Rationale:

When iterating over globs containing expansions, you can still quote all expansions in the path to better handle whitespace and special characters.

Just make sure glob characters are outside quotes. "$dir/*.txt" will not glob expand, but "$dir"/*.txt or "$dir"/*."$ext" will.

Exceptions:

Exceptions similar to SC2086 apply. If the variable is expected to contain globs, such as if dir="tmp/**" in the example, you can ignore this message.

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