Pattern: find with redirection in the middle
Issue: -
This rule checks for find command with a redirection in the middle.
This redirection may have been intended to apply only to a specific action like -exec or -print, but it does in fact apply to the entire find command:
# This command
find . -name '*.ppm' -exec pnmtopng {} > {}.png \;
# Is the same as this
{
find . -name '*.ppm' -exec pnmtopng {} \;
} > {}.png
To perform a redirection per action, rewrite it with e.g. -exec sh -c '...' _ {} \;
If the redirection is something like > /dev/null where you don't mind it applying to the whole find and not individual results, move the redirection to the end of command:
find . -exec foo {} > /dev/null \; # Ambiguous syntax. Is it per -exec or not?
find . -exec foo {} \; > /dev/null # Identical command with clear intent.
Example of incorrect code:
find . -name '*.ppm' -exec pnmtopng {} > {}.png \;Example of correct code:
find . -name '*.ppm' -exec sh -c 'pnmtopng "$1" > "$1.png"' _ {} \;