Calculate incremental repository size changes for each Git commit.

git-commit-size-deltas.sh

#!/bin/sh

# This dumps the sum of file size changes (completely ignoring git repo compression)

git rev-list --all --max-parents=1 | nl -v 0 | while read index commit; do \
  size=$(git ls-tree -r --long "$commit" | awk '{total+=$4} END {print total}'); \
  parent=$(git rev-parse "$commit^" 2>/dev/null); \
  parent_size=$(git ls-tree -r --long "$parent" | awk '{total+=$4} END {print total}'); \
  delta=$((size - parent_size)); \
  short_hash=$(git rev-parse --short "$commit"); \
  summary=$(git log --format=%s -n 1 "$commit"); \
  printf "%3s %7s %10d bytes  %s\n" "$index" "$short_hash" "$delta" "$summary"; \
done