I find this essential, to understand not only what’s about to be updated, but how each relates to:

  • anything it depends on (below)
  • anything that depends on it (above)
    • these are highlighted via red arrow/s (toward the outdated item, which they depend on)
      • if none, the outdated item is likely at the top of the graph, and thus already easy to spot 😏)

Notes:

  • it’s a hack, and somewhat “brute force” (ex: $searchIterations)
  • tested on a Mac, in the Terminal app  
    • overall concept amenable to most command-line settings

Requirements:  

  • homebrew
  • graphviz (and the dot command thereof)
  • misc std command-line utils such as sed
  • a directory ~/tmp/
  • something that can read the final PDF output
    • the output type may be changed; see the dot -O -Tpdf… command

command-line:

brew outdated -q | while read searchRoot; do echo 'checking for '$searchRoot'...'; searchIterations=10; outFile=~/tmp/$(datestamp)_brew_${searchRoot}.gv; fullGraph=$(brew deps --installed --dot --graph --include-requirements --for-each --annotate); nodeList="$searchRoot"; for i in $(seq 1 $searchIterations); do nodeListNew=''; newNodes=$(echo "$fullGraph" | egrep " -> \"($nodeList)" | cut -d\" -f2,4 -s | tr '"' '\n' | sort | uniq | tr '\n' "|" | sed 's/|$//'); if [ -n "$newNodes" ] ; then nodeListNew=$(echo "$nodeList"$'\n'"$newNodes" | tr '|' '\n' | egrep -v '^$' | sort | uniq | tr '\n' "|" | sed 's/|$//'); else break; fi; if [ "$nodeListNew" = "$nodeList" ] ; then break; fi; nodeList=$nodeListNew; done; potOut=$(echo "$fullGraph" | egrep "$nodeList" | sort | uniq | sed "s/ -> \"$searchRoot\"/& [color = red] /"); echo 'digraph {'"$potOut"'}' > "$outFile"; dot -O -Tpdf "$outFile"; open "$outFile".pdf; done