How to diff a commit with its parent

Question

Aside from writing an alias or script, is there a shorter command for getting the diff for a particular commit?

git diff 15dc8^..15dc8

If you only give the single commit id git diff 15dc8, it diffs that commit against HEAD.

Answer

Use git show $COMMIT. It'll show you the log message for the commit, and the diff of that particular commit.

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