[maebeale]

Closes #2963. Scope picked per the recommendation on that issue.

Problem

FormsController#results honored its event filter only for an event connected to the form through event_forms, and the picker offered that same set:

@selected_event_id = @form.events.where(id: params[:event_id]).pick(:id)

A standalone form has no event_forms rows, so for the surveys shared as /f/:slug?event= (#2768) and for the on-demand agreement — both of which stamp an event on the submission — the filter was dead by construction. Staff could see a training's survey responses on the registrants roster but never roll them up on their own.

Change

• Which events — the filterable set is now the events the form's own submissions were made for (Event.where(id: @form.form_submissions.select(:event_id))), one definition shared by the picker and the param check. Standalone forms gain the filter; an event-connected form no longer offers connected events with no submissions, which only ever filtered to an empty rollup. The existing .many? gate still hides the picker for a single-event form.
• Keeping context — the subnav's Results tab carries event_id like the Edit tabs already do, and results runs set_dashboard_event, so the event an admin arrived with survives a trip through the rollup instead of being dropped on one tab out of three.
• Scope — any standalone form, not survey roles only: the rule that matters is "its submissions carry an event," which already covered the on-demand agreement before Associate standalone survey submissions with their event so training feedback automatically tracks on the registrants roster (#2749) #2768, so a role check would leave that one broken for no reason.

Changes

• app/controllers/forms_controller.rb, app/helpers/forms_helper.rb, app/views/forms/results.html.erb
• Specs: a standalone survey's rollup narrows to an event its submissions carry; the picker offers every event with submissions; no picker when every submission is event-less; an event_id with no submissions is ignored; the subnav keeps the event. Three existing filter specs now create the submissions they imply, since connected-but-empty events no longer appear.

Testing

spec/requests/forms_spec.rb (166), plus spec/helpers/forms_helper_spec.rb, spec/requests/{form_submissions,form_answers,public_forms}_spec.rb, spec/services/form_response_aggregator_spec.rb, spec/decorators/form_decorator_spec.rb — 357 examples, 0 failures. Rubocop clean.

🤖 Generated with Claude Code

[maebeale]

Added the Features & tips seed (db/seeds/features/2026-11-08-per-event-form-results.yml, area reporting, admin-facing) in a follow-up commit, per the project rule that a staff-facing improvement ships with one.