compiler: Handle TSNonNullAssertion expressions

Author: henryqdineen

compiler/packages/babel-plugin-react-compiler/src/HIR/BuildHIR.ts

@@ -2407,6 +2407,10 @@ function lowerExpression(
         loc: expr.node.loc ?? GeneratedSource,
       };
     }
+    case "TSNonNullExpression": {
+      let expr = exprPath as NodePath<t.TSNonNullExpression>;
+      return lowerExpression(builder, expr.get("expression"));
+    }
     default: {
       builder.errors.push({
         reason: `(BuildHIR::lowerExpression) Handle ${exprPath.type} expressions`,

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/non-null-assertion.expect.md

@@ -0,0 +1,49 @@
+
+## Input
+
+```javascript
+interface ComponentProps {
+  name?: string;
+}
+
+function Component(props: ComponentProps) {
+  return props.name!.toUpperCase();
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{ name: "Alice" }],
+};
+
+```
+
+## Code
+
+```javascript
+import { c as _c } from "react/compiler-runtime";
+interface ComponentProps {
+  name?: string;
+}
+
+function Component(props) {
+  const $ = _c(2);
+  let t0;
+  if ($[0] !== props.name) {
+    t0 = props.name.toUpperCase();
+    $[0] = props.name;
+    $[1] = t0;
+  } else {
+    t0 = $[1];
+  }
+  return t0;
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{ name: "Alice" }],
+};
+
+```
+      
+### Eval output
+(kind: ok) "ALICE"

compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/non-null-assertion.ts

@@ -0,0 +1,12 @@
+interface ComponentProps {
+  name?: string;
+}
+
+function Component(props: ComponentProps) {
+  return props.name!.toUpperCase();
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: Component,
+  params: [{ name: "Alice" }],
+};