Pattern: Use of unquoted grep pattern
Issue: -
The regex passed to grep frequently contains characters that collide with globs. The code above is supposed to match "f followed by 1 or more o's", but if the directory contains a file called "foo.txt", an unquoted pattern will cause it to become grep foo.txt file.
To prevent this, always quote the regex passed to grep, especially when it contains one or more glob character.
Example of incorrect code:
grep foo* file
Example of correct code:
grep "foo*" file