Remove unnecessary check in getNarrowableTypeForReference

ahejlsberg · ahejlsberg · commit aa1c25d35d13 · 2022-02-18T06:54:04.000-08:00
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -25081,7 +25081,7 @@ namespace ts {
             const substituteConstraints = !(checkMode && checkMode & CheckMode.Inferential) &&
                 someType(type, isGenericTypeWithUnionConstraint) &&
                 (isConstraintPosition(type, reference) || hasContextualTypeWithNoGenericTypes(reference, checkMode));
-            return substituteConstraints ? mapType(type, t => t.flags & TypeFlags.Instantiable && !isMappedTypeGenericIndexedAccess(t) ? getBaseConstraintOrType(t) : t) : type;
+            return substituteConstraints ? mapType(type, t => t.flags & TypeFlags.Instantiable ? getBaseConstraintOrType(t) : t) : type;
         }
 
         function isExportOrExportExpression(location: Node) {

Original file line number	Diff line number	Diff line change
`@@ -25081,7 +25081,7 @@ namespace ts {`
`25081`	`25081`	`const substituteConstraints = !(checkMode && checkMode & CheckMode.Inferential) &&`
`25082`	`25082`	`someType(type, isGenericTypeWithUnionConstraint) &&`
`25083`	`25083`	`(isConstraintPosition(type, reference) \|\| hasContextualTypeWithNoGenericTypes(reference, checkMode));`
`25084`		`- return substituteConstraints ? mapType(type, t => t.flags & TypeFlags.Instantiable && !isMappedTypeGenericIndexedAccess(t) ? getBaseConstraintOrType(t) : t) : type;`
	`25084`	`+ return substituteConstraints ? mapType(type, t => t.flags & TypeFlags.Instantiable ? getBaseConstraintOrType(t) : t) : type;`
`25085`	`25085`	`}`
`25086`	`25086`
`25087`	`25087`	`function isExportOrExportExpression(location: Node) {`