Associate pull requests and issues

[plehegar]

If an issue is created, it may get resolved through one or more pull requests. It would be nice to have a single entry for the issue and the PR in the horizontal tracker.

For example,

w3c/ambient-light#63
resulted in 2 pull requests:
w3c/ambient-light#77
w3c/sensors#429

from @xfq

[plehegar]

Proposal:

• when detecting a pull request (but NOT an issue) links (in the initial comment) to a spec issue already tracked, add a comment to the corresponding horizontal issue saying so.

For example, a comment would be added to w3cping/tracking-issues#242 such as:
[[
https://github.com/w3c/ambient-light/pull/77 might be related to this issue.
]]

• allow linking to multiple spec issues and pull requests in a single horizontal issue. By default, the tool will add the same label to all of them. An extra keyword ("tracker" or "needs-resolution") to indicate if additional issue or pull request needs to differ from the original issue

eg.

w3cping/tracking-issues#242 could say:

[[
§ https://github.com/w3c/ambient-light/issues/63
§ https://github.com/w3c/ambient-light/pull/77 tracker
§ https://github.com/w3c/sensors/pull/429
]]

Intended benefits:

• allow horizontal groups to have horizontal labels on pull requests. This adds those to their email digest if they receive those so they can track the activities related to the issue.
• avoid the creation multiple horizontal issues when one is enough
• Facilitate the checks done by the Director, since the horizontal issue would link everywhere relevant
• avoid false positive from the Director (such as blocking a transition on a pull request because it has "needs-resolution" due of its related issue)

[plehegar]

For horizontal folks, it means:

When receiving a comment indicating that a pull request is related to a horizontal issue, consider adding a link to that pull request to the link(s) listed in the initial of that horizontal issue.

If the horizontal tracker issue has "needs-resolution", consider adding "tracker" after the link unless you'd like the Director to block on it if it's not merged.

[plehegar]

cc @michael-n-cooper @ylafon @samuelweiler @r12a @xfq

[samuelweiler]

If we need to downgrade an issue (from -needs-resolution to -tracker), that creates a larger number of touchpoints that we'll have to fix between runs of the tool, since we'll presumably need to also downgrade all of the linked PRs. Not necessarily a showstopper, just calling out the edge case.

[michael-n-cooper]

I'm not sure I understand how this would look like / work in practice, but the idea seems good. I already manually cross reference issues and pull requests, but it would be good for those relationships to be more visible.

[plehegar]

If we need to downgrade an issue (from -needs-resolution to -tracker), that creates a larger number of touchpoints

indeed. Just curious, how often does this case occur? If it is common, I could think of ways to optimize it.

[ylafon]

I agree that the issue of a PR or issue changing its state is potentially problematic. I bet that changes for the main issue might not happen a lot (if at all), but for "maybe related PRs", it is likely, so we can have mismatchs here.
Otherwise, looks like a nice addition to avoid tracking down things.