[compiler] repro for reactive ref.current accesses (#31519)

See test fixture
---
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* #31521
* __->__ #31519

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/bug-nonreactive-ref.expect.md

@@ -0,0 +1,89 @@
+
+## Input
+
+```javascript
+import {useRef} from 'react';
+import {Stringify} from 'shared-runtime';
+
+/**
+ * Bug: we're currently filtering out `ref.current` dependencies in
+ * `propagateScopeDependencies:checkValidDependency`. This is incorrect.
+ * Instead, we should always take a dependency on ref values (the outer box) as
+ * they may be reactive. Pruning should be done in
+ * `pruneNonReactiveDependencies`
+ *
+ * Found differences in evaluator results
+ * Non-forget (expected):
+ *   (kind: ok)
+ *   <div>{"cb":{"kind":"Function","result":1},"shouldInvokeFns":true}</div>
+ *   <div>{"cb":{"kind":"Function","result":2},"shouldInvokeFns":true}</div>
+ * Forget:
+ *   (kind: ok)
+ *   <div>{"cb":{"kind":"Function","result":1},"shouldInvokeFns":true}</div>
+ *   <div>{"cb":{"kind":"Function","result":1},"shouldInvokeFns":true}</div>
+ */
+function Component({cond}) {
+  const ref1 = useRef(1);
+  const ref2 = useRef(2);
+  const ref = cond ? ref1 : ref2;
+  const cb = () => ref.current;
+  return <Stringify cb={cb} shouldInvokeFns={true} />;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{cond: true}],
+  sequentialRenders: [{cond: true}, {cond: false}],
+};
+
+```
+
+## Code
+
+```javascript
+import { c as _c } from "react/compiler-runtime";
+import { useRef } from "react";
+import { Stringify } from "shared-runtime";
+
+/**
+ * Bug: we're currently filtering out `ref.current` dependencies in
+ * `propagateScopeDependencies:checkValidDependency`. This is incorrect.
+ * Instead, we should always take a dependency on ref values (the outer box) as
+ * they may be reactive. Pruning should be done in
+ * `pruneNonReactiveDependencies`
+ *
+ * Found differences in evaluator results
+ * Non-forget (expected):
+ *   (kind: ok)
+ *   <div>{"cb":{"kind":"Function","result":1},"shouldInvokeFns":true}</div>
+ *   <div>{"cb":{"kind":"Function","result":2},"shouldInvokeFns":true}</div>
+ * Forget:
+ *   (kind: ok)
+ *   <div>{"cb":{"kind":"Function","result":1},"shouldInvokeFns":true}</div>
+ *   <div>{"cb":{"kind":"Function","result":1},"shouldInvokeFns":true}</div>
+ */
+function Component(t0) {
+  const $ = _c(1);
+  const { cond } = t0;
+  const ref1 = useRef(1);
+  const ref2 = useRef(2);
+  const ref = cond ? ref1 : ref2;
+  let t1;
+  if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
+    const cb = () => ref.current;
+    t1 = <Stringify cb={cb} shouldInvokeFns={true} />;
+    $[0] = t1;
+  } else {
+    t1 = $[0];
+  }
+  return t1;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{ cond: true }],
+  sequentialRenders: [{ cond: true }, { cond: false }],
+};
+
+```
+      

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/bug-nonreactive-ref.tsx

@@ -0,0 +1,33 @@
+import {useRef} from 'react';
+import {Stringify} from 'shared-runtime';
+
+/**
+ * Bug: we're currently filtering out `ref.current` dependencies in
+ * `propagateScopeDependencies:checkValidDependency`. This is incorrect.
+ * Instead, we should always take a dependency on ref values (the outer box) as
+ * they may be reactive. Pruning should be done in
+ * `pruneNonReactiveDependencies`
+ *
+ * Found differences in evaluator results
+ * Non-forget (expected):
+ *   (kind: ok)
+ *   <div>{"cb":{"kind":"Function","result":1},"shouldInvokeFns":true}</div>
+ *   <div>{"cb":{"kind":"Function","result":2},"shouldInvokeFns":true}</div>
+ * Forget:
+ *   (kind: ok)
+ *   <div>{"cb":{"kind":"Function","result":1},"shouldInvokeFns":true}</div>
+ *   <div>{"cb":{"kind":"Function","result":1},"shouldInvokeFns":true}</div>
+ */
+function Component({cond}) {
+  const ref1 = useRef(1);
+  const ref2 = useRef(2);
+  const ref = cond ? ref1 : ref2;
+  const cb = () => ref.current;
+  return <Stringify cb={cb} shouldInvokeFns={true} />;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{cond: true}],
+  sequentialRenders: [{cond: true}, {cond: false}],
+};

compiler/packages/snap/src/SproutTodoFilter.ts

@@ -484,6 +484,7 @@ const skipFilter = new Set([
   'bug-aliased-capture-mutate',
   'bug-functiondecl-hoisting',
   'bug-try-catch-maybe-null-dependency',
+  'bug-nonreactive-ref',
   'reduce-reactive-deps/bug-infer-function-cond-access-not-hoisted',
   'bug-invalid-phi-as-dependency',
   'reduce-reactive-deps/bug-merge-uncond-optional-chain-and-cond',