Only check isUnitType when dealing with non-unions.

DanielRosenwasser · DanielRosenwasser · commit 5c134019f86b · 2022-08-24T01:14:05.000Z
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -18901,7 +18901,7 @@ namespace ts {
                         }
                     }
 
-                    const isPerformingCommonPropertyChecks = (relation !== comparableRelation || relation === comparableRelation && isLiteralType(source)) &&
+                    const isPerformingCommonPropertyChecks = (relation !== comparableRelation || !(source.flags & TypeFlags.Union) && isLiteralType(source)) &&
                         !(intersectionState & IntersectionState.Target) &&
                         source.flags & (TypeFlags.Primitive | TypeFlags.Object | TypeFlags.Intersection) && source !== globalObjectType &&
                         target.flags & (TypeFlags.Object | TypeFlags.Intersection) && isWeakType(target) &&

Original file line number	Diff line number	Diff line change
`@@ -18901,7 +18901,7 @@ namespace ts {`
`18901`	`18901`	`}`
`18902`	`18902`	`}`
`18903`	`18903`
`18904`		`- const isPerformingCommonPropertyChecks = (relation !== comparableRelation \|\| relation === comparableRelation && isLiteralType(source)) &&`
	`18904`	`+ const isPerformingCommonPropertyChecks = (relation !== comparableRelation \|\| !(source.flags & TypeFlags.Union) && isLiteralType(source)) &&`
`18905`	`18905`	`!(intersectionState & IntersectionState.Target) &&`
`18906`	`18906`	`source.flags & (TypeFlags.Primitive \| TypeFlags.Object \| TypeFlags.Intersection) && source !== globalObjectType &&`
`18907`	`18907`	`target.flags & (TypeFlags.Object \| TypeFlags.Intersection) && isWeakType(target) &&`