CODEWITHSUNDEEP
git
Edward Z. Yang
Edward Z. Yang

Reputation: 26742

Programatically check if a commit updates a submodule

Is there an easy way to use Git plumbing to programatically check if a submodule was updated in some commit (e.g., HEAD). (You don't care which one, you just want to know that A submodule changed)

Upvotes: 2

Views: 95

Answers (2)

jthill
jthill

Reputation: 60275

To check a commit's changes against its parents with core commands, use

git diff-tree -m -r $commit     # all parents
git diff-tree -r $commit{~,}    # first parent

Submodule entries have type 16, 

git diff-tree -m -r $commit | awk '$1":"$2~/:16/'

will print all changed submodule entries in $commit.

(edit: had -c option on there by mistake, that shows only conflict resolutions, not what was wanted). (edit 2: gaak! Submodule type is 16, not 04. "I knew that". Also, to compare against all parents, use -m)

Upvotes: 3

Felix
Felix

Reputation: 1905

I'm unaware of a built-in way, but this does the job:

git diff $COMMIT~ $COMMIT | grep -qE '^(-|\+)Subproject commit'
echo $?
# Return code 0 if commit contains changes to a subproject
# Return code 1 if commit contains no changes to a subproject

Upvotes: 0

Related Questions