handle pull_request.synchronize action

[gr2m]

closes #3

[gr2m]

let me know if you want me to remove the nock chaining here. I just wanted to make sure you know about it :)

[gr2m]

@hiimbex do you have CI setup yet?

Note that the tests pass although I didn’t implement the handling of the pull_request.synchronize action yet. This is confusing me, it looks like await probot.receive({name: 'pull_request', payload: payloadSynchronize}) does not check payload.action? Any idea?

[gr2m]

For the record the "fix" is simple

-  app.on('pull_request.opened', async context => {
+  app.on([
+    'pull_request.opened',
+    'pull_request.synchronize'
+  ], async context => {

I just don’t want to push it so you can reproduce the tests already pass

[hiimbex]

I'm not quite sure the fix is that simple...

My initial implementation takes the existing PR body and adds content to the end of it. If the bot has already editted it when the PR was first opened you could get a state like:

My pr body!!

----
Link to rendered markdown file: a

-----
Link to rendered markdown file b

Where a was edited when the PR was first opened, and b was editted and triggered from a synchronized event, or worse:

My pr body!!

----
Link to rendered markdown file: a

-----
Link to rendered markdown file a
Link to rendered markdown file b

where you edit a again.

I'm wondering in regards to the tests "passing" if because that payload is not an opened action if maybe it's not being run/triggered at all?

Also, yes should totally set up Travis! I'll get into that!

[hiimbex]

Note that the tests pass although I didn’t implement the handling of the pull_request.synchronize action yet. This is confusing me, it looks like await probot.receive({name: 'pull_request', payload: payloadSynchronize}) does not check payload.action? Any idea?

After running the CI, I see I was wrong about it perhaps not being run at all. Honestly not sure! I'm guessing it's an issue with probot.receive and testing specific, not generally, but would be curious to investigate more, into receive:
https://github.com/probot/probot/blob/ad06bd5e321fdae893f88ef216102e0e330ba782/src/application.ts#L69-L81