Add tc39 stage 0 proposal

package.json

@@ -23,6 +23,7 @@
     "oby": "14.3.1",
     "preact": "^10.17.1",
     "s-js": "^0.4.9",
+    "signal-polyfill": "^0.1.0",
     "solid-js": "^1.7.11",
     "usignal": "^0.9.0"
   },

src/config.ts

@@ -4,6 +4,7 @@ import { angularFramework } from "./frameworks/angularSignals";
 import { compostateFramework } from "./frameworks/compostate";
 import { kairoFramework } from "./frameworks/kairo";
 import { mobxFramework } from "./frameworks/mobx";
+import { tc39SignalsProposalStage0 } from './frameworks/tc39-proposal-signals-stage-0';
 import { molWireFramework } from "./frameworks/molWire";
 import { obyFramework } from "./frameworks/oby";
 import { preactSignalFramework } from "./frameworks/preactSignals";
@@ -17,6 +18,7 @@ import { xReactivityFramework } from "./frameworks/xReactivity";
 export const frameworkInfo: FrameworkInfo[] = [
   { framework: angularFramework, testPullCounts: true },
   { framework: compostateFramework, testPullCounts: true },
+  { framework: tc39SignalsProposalStage0, testPullCounts: true },
   // { framework: kairoFramework, testPullCounts: true },
   // { framework: mobxFramework, testPullCounts: true },
   { framework: molWireFramework, testPullCounts: true },

src/frameworks/tc39-proposal-signals-stage-0.ts

@@ -0,0 +1,66 @@
+import { ReactiveFramework } from "../util/reactiveFramework";
+import { Signal } from "signal-polyfill";
+
+
+export const tc39SignalsProposalStage0: ReactiveFramework = {
+  name: "TC39 Signals Proposal: Stage 0",
+  signal: (initialValue) => {
+    const s = new Signal.State(initialValue);
+    return {
+      write: (v) => s.set(v),
+      read: () => s.get(),
+    };
+  },
+  computed: (fn) => {
+    const c = new Signal.Computed(fn);
+    return {
+      read: () => c.get(),
+    };
+  },
+  effect: (fn) => effect(fn),
+  withBatch: (fn) => {
+    fn();
+    processPending();
+  },
+  withBuild: (fn) => fn(),
+};
+
+let needsEnqueue = false;
+
+const w = new Signal.subtle.Watcher(() => {
+  if (needsEnqueue) {
+    needsEnqueue = false;
+    (async () => {
+      await Promise.resolve();
+      // next micro queue
+      processPending();
+    })();
+  }
+});
+
+function processPending() {
+  needsEnqueue = true;
+
+  for (const s of w.getPending()) {
+    s.get();
+  }
+
+  w.watch();
+}
+
+export function effect(callback) {
+  let cleanup;
+
+  const computed = new Signal.Computed(() => {
+    typeof cleanup === "function" && cleanup();
+    cleanup = callback();
+  });
+
+  w.watch(computed);
+  computed.get();
+
+  return () => {
+    w.unwatch(computed);
+    typeof cleanup === "function" && cleanup();
+  };
+}