SC2143

Instead of [ -n $(foo | grep bar) ], use foo | grep -q bar .

Problematic code:

if [ "$(find . | grep 'IMG[0-9]')" ]
then
  echo "Images found"
fi

Correct code:

if find . | grep -q 'IMG[0-9]'
then
  echo "Images found"
fi

Rationale:

The problematic code has to iterate the entire directory and read all matching lines into memory before making a decision.

The correct code is cleaner and stops at the first matching line, avoiding both iterating the rest of the directory and reading data into memory.

Contraindications

None.