move static flag predicate before get container

Kingwl · Kingwl · commit ee310a42f0c2 · 2018-06-09T03:08:15.000+08:00
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -17110,8 +17110,7 @@ namespace ts {
                 // allow PropertyAccessibility if context is in function with this parameter
                 // static member access is disallow
                 let thisParameter: ParameterDeclaration | undefined;
-                const thisContainer = getThisContainer(node, /* includeArrowFunctions */ false);
-                if (flags & ModifierFlags.Static || !thisContainer || !isFunctionLike(thisContainer) || !(thisParameter = getThisParameter(thisContainer)) || !thisParameter.type) {
+                if (flags & ModifierFlags.Static || !(thisParameter = getThisParameterFromNodeContext(node)) || !thisParameter.type) {
                     error(errorNode, Diagnostics.Property_0_is_protected_and_only_accessible_within_class_1_and_its_subclasses, symbolToString(prop), typeToString(getDeclaringClass(prop) || type));
                     return false;
                 }
@@ -17134,6 +17133,11 @@ namespace ts {
             return true;
         }
 
+        function getThisParameterFromNodeContext (node: Node) {
+            const thisContainer = getThisContainer(node, /* includeArrowFunctions */ false);
+            return thisContainer && isFunctionLike(thisContainer) ? getThisParameter(thisContainer) : undefined;
+        }
+
         function symbolHasNonMethodDeclaration(symbol: Symbol) {
             return forEachProperty(symbol, prop => {
                 const propKind = getDeclarationKindFromSymbol(prop);
