[buildhir] Patch: lower nested OptionalMemberExpr

compiler/forget/src/HIR/BuildHIR.ts

@@ -1871,7 +1871,7 @@ function lowerMemberExpression(
       object: { ...object },
       property: property.node.name,
       loc: exprLoc,
-      optional: t.isOptionalMemberExpression(expr),
+      optional: expr.node.optional ?? false,
     };
     return { object, property: property.node.name, value };
   } else {

compiler/forget/src/HIR/PrintHIR.ts

@@ -349,9 +349,9 @@ export function printInstructionValue(instrValue: ReactiveValue): string {
       break;
     }
     case "PropertyLoad": {
-      value = `PropertyLoad ${printPlace(instrValue.object)}.${
-        instrValue.property
-      }`;
+      value = `PropertyLoad ${printPlace(instrValue.object)}${
+        instrValue.optional ? "?" : ""
+      }.${instrValue.property}`;
       break;
     }
     case "PropertyStore": {

compiler/forget/src/__tests__/fixtures/compiler/_bug.nested-optional-member-expr.js

@@ -1,4 +0,0 @@
-function Component(props) {
-  let x = foo(props.a?.b.c.d);
-  return x;
-}

compiler/forget/src/__tests__/fixtures/compiler/nested-optional-member-expr.expect.md

@@ -2,6 +2,8 @@
 ## Input
 
 ```javascript
+// We should codegen nested optional properties correctly
+// (i.e. placing `?` in the correct PropertyLoad)
 function Component(props) {
   let x = foo(props.a?.b.c.d);
   return x;
@@ -12,12 +14,14 @@ function Component(props) {
 ## Code
 
 ```javascript
+// We should codegen nested optional properties correctly
+// (i.e. placing `?` in the correct PropertyLoad)
 function Component(props) {
   const $ = React.unstable_useMemoCache(2);
   const c_0 = $[0] !== props.a.b.c.d;
   let t0;
   if (c_0) {
-    t0 = foo(props.a?.b?.c?.d);
+    t0 = foo((props.a?.b).c.d);
     $[0] = props.a.b.c.d;
     $[1] = t0;
   } else {

compiler/forget/src/__tests__/fixtures/compiler/nested-optional-member-expr.js

@@ -0,0 +1,6 @@
+// We should codegen nested optional properties correctly
+// (i.e. placing `?` in the correct PropertyLoad)
+function Component(props) {
+  let x = foo(props.a?.b.c.d);
+  return x;
+}