From f7f7a88e19674e6dec8c60ec22601ef347113636 Mon Sep 17 00:00:00 2001
From: Joe Savona <joesavona@fb.com>
Date: Fri, 7 Apr 2023 16:34:51 -0700
Subject: [PATCH] Example suboptimal memoization with non-inlined useMemo

---
 ...seMemo-independently-memoizeable.expect.md | 61 +++++++++++++++++++
 .../useMemo-independently-memoizeable.js      |  9 +++
 2 files changed, 70 insertions(+)
 create mode 100644 compiler/forget/src/__tests__/fixtures/compiler/useMemo-independently-memoizeable.expect.md
 create mode 100644 compiler/forget/src/__tests__/fixtures/compiler/useMemo-independently-memoizeable.js

diff --git a/compiler/forget/src/__tests__/fixtures/compiler/useMemo-independently-memoizeable.expect.md b/compiler/forget/src/__tests__/fixtures/compiler/useMemo-independently-memoizeable.expect.md
new file mode 100644
index 0000000000..fb6918b129
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/compiler/useMemo-independently-memoizeable.expect.md
@@ -0,0 +1,61 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  const [a, b] = useMemo(() => {
+    const items = [];
+    const a = makeObject(props.a);
+    const b = makeObject(props.b);
+    return [a, b];
+  });
+  return [a, b];
+}
+
+```
+
+## Code
+
+```javascript
+function Component(props) {
+  const $ = React.unstable_useMemoCache(7);
+  const c_0 = $[0] !== props.a;
+  let t0;
+  if (c_0) {
+    t0 = () => {
+      const items = [];
+      const a = makeObject(props.a);
+      const b = makeObject(props.b);
+      return [a, b];
+    };
+    $[0] = props.a;
+    $[1] = t0;
+  } else {
+    t0 = $[1];
+  }
+  const c_2 = $[2] !== t0;
+  let t1;
+  if (c_2) {
+    t1 = t0();
+    $[2] = t0;
+    $[3] = t1;
+  } else {
+    t1 = $[3];
+  }
+  const [a_0, b_0] = t1;
+  const c_4 = $[4] !== a_0;
+  const c_5 = $[5] !== b_0;
+  let t2;
+  if (c_4 || c_5) {
+    t2 = [a_0, b_0];
+    $[4] = a_0;
+    $[5] = b_0;
+    $[6] = t2;
+  } else {
+    t2 = $[6];
+  }
+  return t2;
+}
+
+```
+      
\ No newline at end of file
diff --git a/compiler/forget/src/__tests__/fixtures/compiler/useMemo-independently-memoizeable.js b/compiler/forget/src/__tests__/fixtures/compiler/useMemo-independently-memoizeable.js
new file mode 100644
index 0000000000..4f9f5f39c1
--- /dev/null
+++ b/compiler/forget/src/__tests__/fixtures/compiler/useMemo-independently-memoizeable.js
@@ -0,0 +1,9 @@
+function Component(props) {
+  const [a, b] = useMemo(() => {
+    const items = [];
+    const a = makeObject(props.a);
+    const b = makeObject(props.b);
+    return [a, b];
+  });
+  return [a, b];
+}