grep1-8  Exercise 2: rg -uu Against grep
========================================

(Run in the practice repository from the chapter. Make it first with the block at the top of the chapter, then change into the proj folder.)

echo "-uu against grep -rnI, same lines?"
diff <(grep -rnI --exclude-dir=.git TODO . | sed 's|^\./||' | sort) <(rg -uu -n -g '!.git' TODO | tr '\\' / | sort) && echo "  identical"
echo
for level in "" -u -uu -uuu; do printf 'rg %-5s -l TODO: ' "$level"; rg $level -l TODO | wc -l; done
echo
echo "what -u adds (compare rg and rg -u):"
diff <(rg -l TODO | tr '\\' / | sort) <(rg -u -l TODO | tr '\\' / | sort) | grep '^>' | sed 's/^> /  /'
echo "what -uu adds on top of -u:"
diff <(rg -u -l TODO | tr '\\' / | sort) <(rg -uu -l TODO | tr '\\' / | sort) | grep '^>' | sed 's/^> /  /' | cut -c1-60


Output:

-uu against grep -rnI, same lines?
  identical

rg       -l TODO: 4
rg -u    -l TODO: 6
rg -uu   -l TODO: 9
rg -uuu  -l TODO: 10

what -u adds (compare rg and rg -u):
  build/out.js
  debug.log
what -uu adds on top of -u:
  .env
  .git/hooks/sendemail-validate.sample
  .hidden-notes

WHY THIS WORKS AS AN ANSWER
---------------------------
rg -uu switches off ignore files and the hidden-file rule but keeps skipping binary files, which is what grep -rI does; -g '!.git' leaves out the .git folder, which -uu would otherwise search (grep needed --exclude-dir=.git for the same reason). With paths normalised (backslash to slash, the leading ./ removed) and sorted, diff finds no difference.
The counts per level show the three switches in order: -u (1) stops obeying .gitignore, so build/out.js and debug.log appear (and .env is hidden and still skipped); -uu (2) also searches hidden files and folders, which adds .env, .hidden-notes and .git's sample hooks; -uuu (3) also searches binary files, which adds data/logo.bin.
The two difference listings show which files each switch brought in. The lesson for real work is the same as at the end of the chapter: when a search finds less than you expect, step through -u, -uu, -uuu and see where the file appears.