Inline isFlowNarrowable

sandersn · sandersn · commit 24c8de21c471 · 2017-03-07T10:20:02.000-08:00
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -10238,13 +10238,9 @@ namespace ts {
             return false;
         }
 
-        function isFlowNarrowable(reference: Node, type: Type, couldBeUninitialized?: boolean) {
-            return reference.flowNode && (type.flags & TypeFlags.Narrowable || couldBeUninitialized);
-        }
-
         function getFlowTypeOfReference(reference: Node, declaredType: Type, initialType = declaredType, flowContainer?: Node, couldBeUninitialized?: boolean) {
             let key: string;
-            if (!isFlowNarrowable(reference, declaredType, couldBeUninitialized)) {
+            if (!reference.flowNode || !couldBeUninitialized && !(declaredType.flags & TypeFlags.Narrowable)) {
                 return declaredType;
             }
             const visitedFlowStart = visitedFlowCount;

Original file line number	Diff line number	Diff line change
`@@ -10238,13 +10238,9 @@ namespace ts {`
`10238`	`10238`	`return false;`
`10239`	`10239`	`}`
`10240`	`10240`
`10241`		`- function isFlowNarrowable(reference: Node, type: Type, couldBeUninitialized?: boolean) {`
`10242`		`- return reference.flowNode && (type.flags & TypeFlags.Narrowable \|\| couldBeUninitialized);`
`10243`		`- }`
`10244`		`-`
`10245`	`10241`	`function getFlowTypeOfReference(reference: Node, declaredType: Type, initialType = declaredType, flowContainer?: Node, couldBeUninitialized?: boolean) {`
`10246`	`10242`	`let key: string;`
`10247`		`- if (!isFlowNarrowable(reference, declaredType, couldBeUninitialized)) {`
	`10243`	`+ if (!reference.flowNode \|\| !couldBeUninitialized && !(declaredType.flags & TypeFlags.Narrowable)) {`
`10248`	`10244`	`return declaredType;`
`10249`	`10245`	`}`
`10250`	`10246`	`const visitedFlowStart = visitedFlowCount;`