one-liner to extract & count the types of warnings from a c# build

count-warning-types.md

cat build-output.txt | sed -rn 's/^.*\[([A-Z]+[0-9]+)\].*$/\1/p' | sort | uniq -c | sort -nr

Explanation:

                       ↑                                           ↑      ↑         ↑
                       a                                           b      c         d

a

Extracts the warning code (like CS1234 from foo [CS1234]: bar), discarding the rest of the line (and all non-matching lines)

b

sort all codes, so uniq works as intended

c

counts unique occurrences for each code

d

sorts by most-common-first