fix completions protected members in recursive generic types (microsoft#19192) (microsoft#19242)

Kingwl · mhegazy · commit e9841f3899dd · 2017-11-08T17:44:12.000-08:00
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -15162,12 +15162,11 @@ namespace ts {
             if (flags & ModifierFlags.Static) {
                 return true;
             }
-            // An instance property must be accessed through an instance of the enclosing class
-            if (type.flags & TypeFlags.TypeParameter && (type as TypeParameter).isThisType) {
+             if (type.flags & TypeFlags.TypeParameter) {
                 // get the original type -- represented as the type constraint of the 'this' type
-                type = getConstraintOfTypeParameter(<TypeParameter>type);
+                type = (type as TypeParameter).isThisType ? getConstraintOfTypeParameter(<TypeParameter>type) : getBaseConstraintOfType(<TypeParameter>type);
             }
-            if (!(getObjectFlags(getTargetType(type)) & ObjectFlags.ClassOrInterface && hasBaseType(type, enclosingClass))) {
+            if (!type || !hasBaseType(type, enclosingClass)) {
                 error(errorNode, Diagnostics.Property_0_is_protected_and_only_accessible_through_an_instance_of_class_1, symbolToString(prop), typeToString(enclosingClass));
                 return false;
             }
diff --git a/tests/cases/fourslash/completionsForRecursiveGenericTypesMember.ts b/tests/cases/fourslash/completionsForRecursiveGenericTypesMember.ts
@@ -0,0 +1,18 @@
+/// <reference path="fourslash.ts" />
+
+//// export class TestBase<T extends TestBase<T>>
+//// {   
+////     public publicMethod(p: any): void {}
+////     private privateMethod(p: any): void {}
+////     protected protectedMethod(p: any): void {}
+////     public test(t: T): void
+////     {
+////         t./**/
+////     }
+//// }
+
+goTo.marker();
+
+verify.completionListContains('publicMethod');
+verify.completionListContains('privateMethod');
+verify.completionListContains('protectedMethod');

Original file line number	Diff line number	Diff line change
`@@ -15162,12 +15162,11 @@ namespace ts {`
`15162`	`15162`	`if (flags & ModifierFlags.Static) {`
`15163`	`15163`	`return true;`
`15164`	`15164`	`}`
`15165`		`- // An instance property must be accessed through an instance of the enclosing class`
`15166`		`- if (type.flags & TypeFlags.TypeParameter && (type as TypeParameter).isThisType) {`
	`15165`	`+ if (type.flags & TypeFlags.TypeParameter) {`
`15167`	`15166`	`// get the original type -- represented as the type constraint of the 'this' type`
`15168`		`- type = getConstraintOfTypeParameter(<TypeParameter>type);`
	`15167`	`+ type = (type as TypeParameter).isThisType ? getConstraintOfTypeParameter(<TypeParameter>type) : getBaseConstraintOfType(<TypeParameter>type);`
`15169`	`15168`	`}`
`15170`		`- if (!(getObjectFlags(getTargetType(type)) & ObjectFlags.ClassOrInterface && hasBaseType(type, enclosingClass))) {`
	`15169`	`+ if (!type \|\| !hasBaseType(type, enclosingClass)) {`
`15171`	`15170`	`error(errorNode, Diagnostics.Property_0_is_protected_and_only_accessible_through_an_instance_of_class_1, symbolToString(prop), typeToString(enclosingClass));`
`15172`	`15171`	`return false;`
`15173`	`15172`	`}`