Add Summarize Amount Of Change For Specific Commit as a Git TIL

git/summarize-amount-of-change-for-specific-commit.md

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+# Summarize Amount Of Change For Specific Commit
+
+To get a quick headline summary of the amount of change that happened in a
+commit, I can use the `--shortstat` flag. This will sum up file changed, lines
+added, and lines removed. This can be combined with an _empty_ format flag to
+suppress all other output.
+
+I can run this for the latest commit on the current branch by referencing
+`HEAD`.
+
+```bash
+❯ git show --shortstat --format= HEAD
+ 3 files changed, 1046 insertions(+), 462 deletions(-)
+```
+
+Or I can point at some other commit via its SHA:
+
+```bash
+❯ git show --shortstat --format= 8cbfcdd7
+ 1 file changed, 238 insertions(+)
+```
+
+I can even summarize the amount of change for the entire feature branch I'm
+working on by referencing a range between `main` and the `HEAD` commit.
+
+```bash
+❯ git diff --shortstat main...HEAD
+ 36 files changed, 1125 insertions(+), 134 deletions(-)
+```
+
+See `man git-show` and `man git-diff` for more details.