Update comment

ahejlsberg · ahejlsberg · commit a0c5608770b9 · 2016-08-08T09:44:24.000-07:00
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -8538,9 +8538,10 @@ namespace ts {
                     }
                 }
                 // If the candidate type is a subtype of the target type, narrow to the candidate type.
-                // Otherwise, narrow to whichever of the target type or the candidate type that is assignable
-                // to the other. Otherwise, the types are completely unrelated, so narrow to an intersection
-                // of the two types.
+                // Otherwise, if the target type is assignable to the candidate type, keep the target type.
+                // Otherwise, if the candidate type is assignable to the target type, narrow to the candidate
+                // type. Otherwise, the types are completely unrelated, so narrow to an intersection of the
+                // two types.
                 const targetType = type.flags & TypeFlags.TypeParameter ? getApparentType(type) : type;
                 return isTypeSubtypeOf(candidate, targetType) ? candidate :
                     isTypeAssignableTo(type, candidate) ? type :

Original file line number	Diff line number	Diff line change
`@@ -8538,9 +8538,10 @@ namespace ts {`
`8538`	`8538`	`}`
`8539`	`8539`	`}`
`8540`	`8540`	`// If the candidate type is a subtype of the target type, narrow to the candidate type.`
`8541`		`- // Otherwise, narrow to whichever of the target type or the candidate type that is assignable`
`8542`		`- // to the other. Otherwise, the types are completely unrelated, so narrow to an intersection`
`8543`		`- // of the two types.`
	`8541`	`+ // Otherwise, if the target type is assignable to the candidate type, keep the target type.`
	`8542`	`+ // Otherwise, if the candidate type is assignable to the target type, narrow to the candidate`
	`8543`	`+ // type. Otherwise, the types are completely unrelated, so narrow to an intersection of the`
	`8544`	`+ // two types.`
`8544`	`8545`	`const targetType = type.flags & TypeFlags.TypeParameter ? getApparentType(type) : type;`
`8545`	`8546`	`return isTypeSubtypeOf(candidate, targetType) ? candidate :`
`8546`	`8547`	`isTypeAssignableTo(type, candidate) ? type :`