Today I learned a new way to write today I learned posts!
Sometimes I have want to publish a quick blog post when I'm not at my regular computer with my full development environment set up. (On a loaner laptop while mine is getting repairs, or, I don't know, on a short break from work, for example.)
In the past I've written files directly in Github's web UI, which I merge directly to the primary branch (which triggers a deployment in Netlify). Today I realized that since I have Netlify Deploy Previews enabled, I can make a pull request, and even add multiple files to it, all from github.com, and see what my site will look like when the posts get rendered, right from my browser, with no extra dependencies installed or running. Woo!
# update 1
(today I might also have learned, using this feature, that the changes I pushed this weekend didn't deploy correctly. Oops. TIL to verify your deploys even if usually it /~just works/~.)
# update 2
(ok now I have learned something else - I made a separate pull request to fix the configuration bork that made the site not deploy. But now my netlify preview won't update - even if I try running the build again, it's like it's not pulling the latest changes from my primary branch to merge with, and it keeps failing with the same error. Luckily I have more text to add about it; I bet once I add this additional commit, the deploy preview will work.)
# update 3
(ok that did not work, Netlify is still not updating. Guess I'll have to merge the primary branch into my PR branch manually, then push to update the PR in order to see my deploy preview)
# update 4
After a lot of back & forth with Netlify support to make it clear that my issue was not that I didn't understand the behavior, but rather that the behavior that happened (and that support was explaining was happening) was different than the behavior currently described by the docs for build previews, Netlify now understands the discrepancy and plans to address it.
Tl;dr is that the docs say that the build preview will show the result of merging the PR, but what the preview actually shows is exactly what is on the PR branch, without the merge into the production branch.