swarm-wire, swarm-ui: the flow schema lists the values a field takes, and the editor picks them instead of asking for typed names

The schema's event fields gain values, a values_from marker (agents, repos)
and a closed flag; a node field gains the marker and the flag. kind is now
listed as issue and PR, what the router sends. The flow editor shows a
dropdown where the list is complete, suggestions where it is only examples,
and a plain box where there is none.

frontend/packages/swarm-ui/test/flow-choices.test.mjs

@@ -0,0 +1,148 @@
+// What the flow editor offers for a value: dropdown, suggestions or plain
+// text, from the server's schema. Run by `npm test`.
+import assert from "node:assert/strict";
+import { test } from "node:test";
+import {
+  eventSpec,
+  kindSpec,
+  markersIn,
+  offerFor,
+} from "../src/pages/notifications/FlowChoices.ts";
+
+const d = (name, description = "") => ({ name, description });
+
+const schema = {
+  source_events: [d("issues")],
+  fields: [
+    {
+      ...d("kind"),
+      values: [d("issue"), d("PR", "A pull request")],
+      closed: true,
+    },
+    { ...d("action"), values: [d("opened"), d("closed")], closed: false },
+    { ...d("repo"), values: [], values_from: "repos", closed: false },
+    { ...d("title"), values: [] },
+  ],
+  node_kinds: [
+    {
+      kind: "todo",
+      description: "",
+      fields: [
+        {
+          ...d("to"),
+          required: true,
+          values: [],
+          values_from: "agents",
+          closed: true,
+        },
+        {
+          ...d("op"),
+          required: true,
+          values: [d("upsert"), d("clear")],
+          closed: true,
+        },
+      ],
+    },
+    {
+      kind: "request_reviewer",
+      description: "",
+      fields: [
+        {
+          ...d("reviewer"),
+          required: true,
+          values: [],
+          values_from: "agents",
+          closed: false,
+        },
+        {
+          ...d("later"),
+          required: false,
+          values: [],
+          values_from: "somewhere-new",
+        },
+      ],
+    },
+  ],
+  limits: { max_nodes: 1, max_depth: 1, max_flows: 1 },
+};
+
+test("a field with a complete list is a dropdown, its labels carrying the description", () => {
+  const offer = offerFor(eventSpec(schema, "kind"), {}, "PR");
+  assert.equal(offer.closed, true);
+  assert.deepEqual(
+    offer.options.map((o) => o.value),
+    ["issue", "PR"],
+  );
+  assert.equal(offer.options[1].label, "PR — A pull request");
+});
+
+test("a list that is only examples stays a text box with suggestions", () => {
+  const offer = offerFor(eventSpec(schema, "action"), {}, "");
+  assert.equal(offer.closed, false);
+  assert.deepEqual(
+    offer.options.map((o) => o.value),
+    ["opened", "closed"],
+  );
+});
+
+test("a field with no known values is plain text", () => {
+  assert.equal(offerFor(eventSpec(schema, "title"), {}, ""), null);
+  assert.equal(offerFor(undefined, {}, ""), null, "no schema entry at all");
+});
+
+test("a list fetched from the swarm fills the options, and a closed one becomes a dropdown", () => {
+  const spec = kindSpec(schema, "todo", "to");
+  const offer = offerFor(spec, { agents: ["atlas", "iris"] }, "iris");
+  assert.equal(offer.closed, true);
+  assert.deepEqual(
+    offer.options.map((o) => o.value),
+    ["atlas", "iris"],
+  );
+});
+
+test("until its list arrives, or when it cannot be fetched, there is nothing to offer", () => {
+  const spec = kindSpec(schema, "todo", "to");
+  assert.equal(offerFor(spec, {}, ""), null);
+  // Open lists with names fetched are suggestions: any login still goes.
+  const reviewer = kindSpec(schema, "request_reviewer", "reviewer");
+  const offer = offerFor(reviewer, { agents: ["argus"] }, "review-classifier");
+  assert.equal(offer.closed, false);
+  assert.deepEqual(
+    offer.options.map((o) => o.value),
+    ["argus"],
+  );
+});
+
+test("a dropdown whose source has not arrived falls back to suggestions", () => {
+  const spec = {
+    values: [d("a")],
+    values_from: "agents",
+    closed: true,
+  };
+  assert.equal(offerFor(spec, {}, "").closed, false);
+  assert.equal(offerFor(spec, { agents: ["b"] }, "").closed, true);
+});
+
+test("a value the list lacks stays selectable, marked as not listed", () => {
+  const spec = kindSpec(schema, "todo", "to");
+  const offer = offerFor(spec, { agents: ["atlas"] }, "gone");
+  assert.equal(offer.options[0].value, "gone");
+  assert.equal(offer.options[0].label, "gone (not listed)");
+  assert.equal(offer.options.length, 2);
+  // Nothing set yet adds nothing.
+  assert.equal(offerFor(spec, { agents: ["atlas"] }, "").options.length, 1);
+});
+
+test("a name in both the fixed values and the fetched list is offered once", () => {
+  const spec = { values: [d("x")], values_from: "agents" };
+  const offer = offerFor(spec, { agents: ["x", "y"] }, "");
+  assert.deepEqual(
+    offer.options.map((o) => o.value),
+    ["x", "y"],
+  );
+});
+
+test("the markers to fetch are the ones the schema names and the editor knows, once each", () => {
+  assert.deepEqual(markersIn(schema), ["agents", "repos"]);
+  assert.deepEqual(markersIn({ ...schema, fields: [], node_kinds: [] }), []);
+});