Remove unnecessary widening, more PR feedback

Author: rbuckton

src/compiler/checker.ts

@@ -16493,7 +16493,6 @@ namespace ts {
             //  }
             //
 
-            // TODO(rbuckton): Verify whether we need to call getApparentType. See checkNonThenableType in master
             const thenFunction = getTypeOfPropertyOfType(type, "then");
             const thenSignatures = thenFunction ? getSignaturesOfType(thenFunction, SignatureKind.Call) : emptyArray;
             if (thenSignatures.length > 0) {
@@ -16600,7 +16599,7 @@ namespace ts {
                 if (type.id === promisedType.id || indexOf(awaitedTypeStack, promisedType.id) >= 0) {
                     // Verify that we don't have a bad actor in the form of a promise whose
                     // promised type is the same as the promise type, or a mutually recursive
-                    // promise. If so, we returnundefined as we cannot guess the shape. If this
+                    // promise. If so, we return undefined as we cannot guess the shape. If this
                     // were the actual case in the JavaScript, this Promise would never resolve.
                     //
                     // An example of a bad actor with a singly-recursive promise type might
@@ -16664,15 +16663,14 @@ namespace ts {
             // of a runtime problem. If the user wants to return this value from an async
             // function, they would need to wrap it in some other value. If they want it to
             // be treated as a promise, they can cast to <any>.
-            const widenedType = getWidenedType(type);
-            if (isThenableType(widenedType)) {
+            if (isThenableType(type)) {
                 if (errorNode) {
                     error(errorNode, Diagnostics.Type_used_as_operand_to_await_or_the_return_type_of_an_async_function_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member);
                 }
                 return undefined;
             }
 
-            return typeAsAwaitable.awaitedTypeOfType = widenedType;
+            return typeAsAwaitable.awaitedTypeOfType = type;
         }
 
         /**

src/compiler/comments.ts

@@ -262,8 +262,7 @@ namespace ts {
 
         function forEachLeadingCommentToEmit(pos: number, cb: (commentPos: number, commentEnd: number, kind: SyntaxKind, hasTrailingNewLine: boolean, rangePos: number) => void) {
             // Emit the leading comments only if the container's pos doesn't match because the container should take care of emitting these comments
-            if ((containerPos === -1 || pos !== containerPos) /* && !leadingCommentPositions[pos] */) {
-                // leadingCommentPositions[pos] = true;
+            if ((containerPos === -1 || pos !== containerPos)) {
                 if (hasDetachedComments(pos)) {
                     forEachLeadingCommentWithoutDetachedComments(cb);
                 }
@@ -275,8 +274,7 @@ namespace ts {
 
         function forEachTrailingCommentToEmit(end: number, cb: (commentPos: number, commentEnd: number, kind: SyntaxKind, hasTrailingNewLine: boolean) => void) {
             // Emit the trailing comments only if the container's end doesn't match because the container should take care of emitting these comments
-            if ((containerEnd === -1 || (end !== containerEnd && end !== declarationListContainerEnd)) /*&& !trailingCommentPositions[end] */) {
-                // trailingCommentPositions[end] = true;
+            if ((containerEnd === -1 || (end !== containerEnd && end !== declarationListContainerEnd))) {
                 forEachTrailingCommentRange(currentText, end, cb);
             }
         }

tests/baselines/reference/castOfAwait.types

@@ -18,7 +18,7 @@ async function f() {
 >0 : 0
 
     await void <string> typeof <number> void await 0;
->await void <string> typeof <number> void await 0 : any
+>await void <string> typeof <number> void await 0 : undefined
 >void <string> typeof <number> void await 0 : undefined
 ><string> typeof <number> void await 0 : string
 >typeof <number> void await 0 : string