Add Run A Task If It Meets Criteria as a Taskfile TIL

taskfile/run-a-task-if-it-meets-criteria.md

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+# Run A Task If It Meets Criteria
+
+The [Taskfile `status`
+directive](https://taskfile.dev/docs/guide#limiting-when-tasks-run) can be used
+to tell a task when it needs to run. If it doesn't need to run, it can be
+skipped over. The idea being that we're making a status check to see if we're
+up-to-date or need to run the task.
+
+For instance, here is a `status` check that determines if there are changes to
+commit and push. If there are changes to `NOTES.md`, then we are out-of-date and
+need to run the `cmds` that make up the task.
+
+```yaml
+  notes:push:
+    desc: Commit and push changes to notes submodule
+    dir: '{{.NOTES_DIR}}'
+    cmds:
+      - git add NOTES.md
+      - git commit -m "Update notes - $(date '+%Y-%m-%d %H:%M')"
+      - git push
+    status:
+      - git diff --exit-code NOTES.md
+    silent: false
+```
+
+This is useful because I don't want the `git add`, `git commit`, and `git push`
+commands to run when there is nothing to do.
+
+Note: this is different from the `preconditions` directive. Instead of
+short-circuiting a sequence of tasks, this will either run or skip the task and
+move on to the next one.