follow advise

YuichiNukiyama · YuichiNukiyama · commit 0c01874b310e · 2016-08-20T21:24:46.000+09:00
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -6258,13 +6258,6 @@ namespace ts {
                     targetType = typeToString(target, /*enclosingDeclaration*/ undefined, TypeFormatFlags.UseFullyQualifiedType);
                 }
 
-                // check if trying to relate primitives to the boxed/apparent backing types.
-                if ((sourceType === "Number" && targetType === "number") ||
-                    (sourceType === "String" && targetType === "string") ||
-                    (sourceType === "Boolean" && targetType === "boolean")) {
-                        reportError(Diagnostics._0_is_a_primitive_type_while_1_is_a_boxed_object_Prefer_using_0_when_possible, targetType, sourceType);
-                }
-
                 if (!message) {
                     message = relation === comparableRelation ?
                         Diagnostics.Type_0_is_not_comparable_to_type_1 :
@@ -6274,6 +6267,19 @@ namespace ts {
                 reportError(message, sourceType, targetType);
             }
 
+            function tryElaborateErrorsForPrimitivesAndObjects(source: Type, target: Type) {
+                const sourceType = typeToString(source);
+                const targetType = typeToString(target);
+
+                if ((globalStringType === source && stringType === target) ||
+                    (globalNumberType === source && numberType === target) ||
+                    (globalBooleanType === source && booleanType === target) ||
+                    (getGlobalESSymbolType() === source && esSymbolType === target)) {
+                        console.log(source);console.log(target);
+                        reportError(Diagnostics._0_is_a_primitive_type_while_1_is_a_boxed_object_Prefer_using_0_when_possible, targetType, sourceType);
+                }
+            }
+
             // Compare two types and return
             // Ternary.True if they are related with no assumptions,
             // Ternary.Maybe if they are related with assumptions of other relationships, or
@@ -6396,6 +6402,10 @@ namespace ts {
                     }
                 }
 
+                if (source.flags & TypeFlags.ObjectType && target.flags & TypeFlags.Primitive) {
+                    tryElaborateErrorsForPrimitivesAndObjects(source, target);
+                }
+
                 if (reportErrors) {
                     reportRelationError(headMessage, source, target);
                 }
diff --git a/tests/baselines/reference/symbolType15.errors.txt b/tests/baselines/reference/symbolType15.errors.txt
@@ -1,4 +1,5 @@
 tests/cases/conformance/es6/Symbols/symbolType15.ts(5,1): error TS2322: Type 'Symbol' is not assignable to type 'symbol'.
+  'symbol' is a primitive type while 'Symbol' is a boxed object. Prefer using 'symbol' when possible.
 
 
 ==== tests/cases/conformance/es6/Symbols/symbolType15.ts (1 errors) ====
@@ -8,4 +9,5 @@ tests/cases/conformance/es6/Symbols/symbolType15.ts(5,1): error TS2322: Type 'Sy
     symObj = sym;
     sym = symObj;
     ~~~
-!!! error TS2322: Type 'Symbol' is not assignable to type 'symbol'.
+!!! error TS2322: Type 'Symbol' is not assignable to type 'symbol'.
+!!! error TS2322:   'symbol' is a primitive type while 'Symbol' is a boxed object. Prefer using 'symbol' when possible.
diff --git a/tests/cases/compiler/nativeToBoxedTypes.ts b/tests/cases/compiler/nativeToBoxedTypes.ts
@@ -8,4 +8,8 @@ s = S;
 
 var B = new Boolean();
 var b = true;
-b = B;
+b = B;
+
+var sym: symbol; 
+var Sym: Symbol;
+sym = Sym;
