[compiler][repro] JSX escape sequences not printed correctly by @babe…

…l/generator (#32130)

Repro for #32123

Note that this is only a bug when calling `@babel/generator:generate()`
before transforming JSX.
---
[//]: # (BEGIN SAPLING FOOTER)
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* #32131
* __->__ #32130

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/jsx-preserve-escape-character.expect.md

@@ -0,0 +1,57 @@
+
+## Input
+
+```javascript
+/**
+ * Fixture showing `@babel/generator` bug with jsx attribute strings containing
+ * escape sequences. Note that this is only a problem when generating jsx
+ * literals.
+ *
+ * When using the jsx transform to correctly lower jsx into
+ * `React.createElement` calls, the escape sequences are preserved correctly
+ * (see evaluator output).
+ */
+function MyApp() {
+  return <input pattern="\w" />;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: MyApp,
+  params: [],
+};
+
+```
+
+## Code
+
+```javascript
+import { c as _c } from "react/compiler-runtime"; /**
+ * Fixture showing `@babel/generator` bug with jsx attribute strings containing
+ * escape sequences. Note that this is only a problem when generating jsx
+ * literals.
+ *
+ * When using the jsx transform to correctly lower jsx into
+ * `React.createElement` calls, the escape sequences are preserved correctly
+ * (see evaluator output).
+ */
+function MyApp() {
+  const $ = _c(1);
+  let t0;
+  if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
+    t0 = <input pattern="\\w" />;
+    $[0] = t0;
+  } else {
+    t0 = $[0];
+  }
+  return t0;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: MyApp,
+  params: [],
+};
+
+```
+      
+### Eval output
+(kind: ok) <input pattern="\w">

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/jsx-preserve-escape-character.js

@@ -0,0 +1,17 @@
+/**
+ * Fixture showing `@babel/generator` bug with jsx attribute strings containing
+ * escape sequences. Note that this is only a problem when generating jsx
+ * literals.
+ *
+ * When using the jsx transform to correctly lower jsx into
+ * `React.createElement` calls, the escape sequences are preserved correctly
+ * (see evaluator output).
+ */
+function MyApp() {
+  return <input pattern="\w" />;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: MyApp,
+  params: [],
+};