Support unused conditional/logical expressions assigned to variable

I noticed some instances of this error when running forget on an internal 
product. I previously fixed the case if a logical/conditional used only for side 
effects (not assigned to a variable) but the new cases were assigned to an 
unused variable. I double-checked and we’ve actually fixed all the steps after 
these invariants so we can just remove them and support these cases.

compiler/forget/src/ReactiveScopes/BuildReactiveFunction.ts

@@ -6,7 +6,6 @@
  */
 
 import invariant from "invariant";
-import { CompilerError } from "../CompilerError";
 import {
   BasicBlock,
   BlockId,
@@ -826,12 +825,6 @@ class Driver {
           testBlock.terminal.alternate,
           terminal.loc
         );
-        if (leftFinal.place.identifier !== right.place.identifier) {
-          CompilerError.todo(
-            "TODO: Support LogicalExpression whose value is unused",
-            leftFinal.place.loc
-          );
-        }
         const value: ReactiveLogicalValue = {
           kind: "LogicalExpression",
           operator: terminal.operator,
@@ -869,12 +862,6 @@ class Driver {
           alternate: alternate.value,
           loc: terminal.loc,
         };
-        if (consequent.place.identifier !== alternate.place.identifier) {
-          CompilerError.todo(
-            "TODO: Support ConditionalExpression whose value is unused",
-            consequent.place.loc
-          );
-        }
 
         return {
           place: { ...consequent.place },

compiler/forget/src/__tests__/fixtures/compiler/unused-logical-assigned-to-variable.expect.md

@@ -0,0 +1,26 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  // unused!
+  const obj = makeObject();
+  const obj2 = makeObject();
+  const _ = (obj.a ?? obj2.b) || props.c;
+  return null;
+}
+
+```
+
+## Code
+
+```javascript
+function Component(props) {
+  const obj = makeObject();
+  const obj2 = makeObject();
+  (obj.a ?? obj2.b) || props.c;
+  return null;
+}
+
+```
+      

compiler/forget/src/__tests__/fixtures/compiler/unused-logical-assigned-to-variable.js

@@ -0,0 +1,7 @@
+function Component(props) {
+  // unused!
+  const obj = makeObject();
+  const obj2 = makeObject();
+  const _ = (obj.a ?? obj2.b) || props.c;
+  return null;
+}

compiler/forget/src/__tests__/fixtures/compiler/unused-optional-method-assigned-to-variable.expect.md

@@ -0,0 +1,24 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  // unused!
+  const obj = makeObject();
+  const _ = obj.a?.b?.(props.c);
+  return null;
+}
+
+```
+
+## Code
+
+```javascript
+function Component(props) {
+  const obj = makeObject();
+  obj.a?.b?.(props.c);
+  return null;
+}
+
+```
+      

compiler/forget/src/__tests__/fixtures/compiler/unused-optional-method-assigned-to-variable.js

@@ -0,0 +1,6 @@
+function Component(props) {
+  // unused!
+  const obj = makeObject();
+  const _ = obj.a?.b?.(props.c);
+  return null;
+}

compiler/forget/src/__tests__/fixtures/compiler/unused-ternary-assigned-to-variable.expect.md

@@ -0,0 +1,24 @@
+
+## Input
+
+```javascript
+function Component(props) {
+  // unused!
+  const obj = makeObject();
+  const _ = obj.a ? props.b : props.c;
+  return null;
+}
+
+```
+
+## Code
+
+```javascript
+function Component(props) {
+  const obj = makeObject();
+  obj.a ? props.b : props.c;
+  return null;
+}
+
+```
+      

compiler/forget/src/__tests__/fixtures/compiler/unused-ternary-assigned-to-variable.js

@@ -0,0 +1,6 @@
+function Component(props) {
+  // unused!
+  const obj = makeObject();
+  const _ = obj.a ? props.b : props.c;
+  return null;
+}