do_stats

#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
#
# Copyright IBM Corp. 2008,2025
#

set -u

base=$1
next=$2
rc=$3

# to stabilise the sorts
export LANG=C

sd=../stats

[ -d $sd ] || mkdir $sd || {
	echo "No stats dir" 1>&2
	exit 1
}

git rev-list --no-merges "$base..$next" | sort >"$sd/$next".sha1s
git rev-list --no-merges "$base..$rc" | sort >"$sd/$rc".sha1s

# filter out the common commits
comm -12 "$sd/$next".sha1s "$sd/$rc".sha1s >"$sd"/common_sha1
comm -23 "$sd/$next".sha1s "$sd/$rc".sha1s >"$sd/$next".sha1s.1
comm -13 "$sd/$next".sha1s "$sd/$rc".sha1s >"$sd/$rc".sha1s.1

# now find commits with the same patch-id
git diff-tree -p --stdin <"$sd/$next".sha1s.1 |
	git patch-id |
	sort >"$sd/$next".patch_ids
git diff-tree -p --stdin <"$sd/$rc".sha1s.1 |
	git patch-id |
	sort >$"sd/$rc".patch_ids
join -j 1 "$sd/$next".patch_ids "$sd/$rc".patch_ids >"$sd"/common_id
join -v 1 -j 1 "$sd/$next".patch_ids "$sd/$rc".patch_ids |
	sed 's/^.* //' >"$sd/$next".sha1s.2
join -v 2 -j 1 "$sd/$next".patch_ids "$sd/$rc".patch_ids |
	sed 's/^.* //' >"$sd/$rc".sha1s.2

# now find commits with the same subject line
git log --stdin --no-walk --format='%s|%H' <"$sd/$next".sha1s.2 |
	sed 's/|\(.*\)|/_\1|/g' |
	sort -f -k 1,1 -t '|' >"$sd/$next".subj
git log --stdin --no-walk --format='%s|%H' <"$sd/$rc".sha1s.2 |
	sed 's/|\(.*\)|/_\1|/g' |
	sort -f -k 1,1 -t '|' >"$sd/$rc".subj
join -i -j 1 -t '|' "$sd/$next".subj "$sd/$rc".subj >"$sd"/common_subj
join -v 1 -i -j 1 -t '|' "$sd/$next".subj "$sd/$rc".subj |
	sed 's/^.*|//' >"$sd/$next".sha1s.3
join -v 2 -i -j 1 -t '|' "$sd/$next".subj "$sd/$rc".subj |
	sed 's/^.*|//' >"$sd/$rc".sha1s.3

nrc=$(wc -l <"$sd/$rc".sha1s)
nnext=$(wc -l <"$sd/$next".sha1s)
ncommsha1=$(wc -l <"$sd"/common_sha1)
ncommid=$(wc -l <"$sd"/common_id)
ncommsubj=$(wc -l <"$sd"/common_subj)
ncomm=$((ncommsha1+ncommid+ncommsubj))
pcomm=$((ncomm*100/nrc))

cat <<EOF
Hi all,

As usual, the executive friendly graph is at
http://neuling.org/linux-next-size.html :-)

(No merge commits counted, $next was the first linux-next after
the merge window opened.)

EOF
printf "%-50s %5d\n" "Commits in $rc (relative to $base):" "$nrc"
printf "%-50s %5d\n" "Commits in $next:" "$nnext"
printf "%-50s %5d\n" "Commits with the same SHA1:" "$ncommsha1"
printf "%-50s %5d (1)\n" "Commits with the same patch_id:" "$ncommid"
printf "%-50s %5d (1)\n" "Commits with the same subject line:" "$ncommsubj"

cat <<EOF

(1) not counting those in the lines above.

EOF

printf "%-50s %5d %2d%%\n" "So commits in -rc1 that were in $next:" $ncomm $pcomm

cat <<EOF

Some breakdown of the list of extra commits (relative to $next)
in -rc1:

Top ten first word of commit summary:

$(git log --no-walk --stdin --pretty="format:%s" <"$sd/$rc".sha1s.3 |
	sed -e 's/^\[//;s/[]:( /,;].*$//' |
	tr '[:upper:]' '[:lower:]' | sort | uniq -c | sort -nr | head -n 10)

Top ten authors:

$(git log --no-walk --stdin --pretty="format:%aE" <"$sd/$rc".sha1s.3 |
	tr '[:upper:]' '[:lower:]' | sort | uniq -c | sort -nr | head -n 10)

Top ten committers:

$(git log --no-walk --stdin --pretty="format:%cE" <"$sd/$rc".sha1s.3 |
	tr '[:upper:]' '[:lower:]' | sort | uniq -c | sort -nr | head -n 10)

There are also $(wc -l <"$sd/$next".sha1s.3) commits in $next that didn't make it into
$rc.

Top ten first word of commit summary:

$(git log --no-walk --stdin --pretty="format:%s" <"$sd/$next".sha1s.3 |
	sed -e 's/^\[//;s/[]:( /,;].*$//' |
	tr '[:upper:]' '[:lower:]' | sort | uniq -c | sort -nr | head -n 10)

Top ten authors:

$(git log --no-walk --stdin --pretty="format:%aE" <"$sd/$next".sha1s.3 |
	tr '[:upper:]' '[:lower:]' | sort | uniq -c | sort -nr | head -n 10)

Top ten committers:

$(git log --no-walk --stdin --pretty="format:%cE" <"$sd/$next".sha1s.3 |
	tr '[:upper:]' '[:lower:]' | sort | uniq -c | sort -nr | head -n 10)
EOF