Remove unneeded ExportType and ExportNamespace flags (#16766)

Author: Andy

src/compiler/binder.ts

@@ -416,9 +416,8 @@ namespace ts {
                 }
             }
             else {
-                // Exported module members are given 2 symbols: A local symbol that is classified with an ExportValue,
-                // ExportType, or ExportContainer flag, and an associated export symbol with all the correct flags set
-                // on it. There are 2 main reasons:
+                // Exported module members are given 2 symbols: A local symbol that is classified with an ExportValue flag,
+                // and an associated export symbol with all the correct flags set on it. There are 2 main reasons:
                 //
                 //   1. We treat locals and exports of the same name as mutually exclusive within a container.
                 //      That means the binder will issue a Duplicate Identifier error if you mix locals and exports
@@ -438,10 +437,7 @@ namespace ts {
                     (node as JSDocTypedefTag).name.kind === SyntaxKind.Identifier &&
                     ((node as JSDocTypedefTag).name as Identifier).isInJSDocNamespace;
                 if ((!isAmbientModule(node) && (hasExportModifier || container.flags & NodeFlags.ExportContext)) || isJSDocTypedefInJSDocNamespace) {
-                    const exportKind =
-                        (symbolFlags & SymbolFlags.Value ? SymbolFlags.ExportValue : 0) |
-                        (symbolFlags & SymbolFlags.Type ? SymbolFlags.ExportType : 0) |
-                        (symbolFlags & SymbolFlags.Namespace ? SymbolFlags.ExportNamespace : 0);
+                    const exportKind = symbolFlags & SymbolFlags.Value ? SymbolFlags.ExportValue : 0;
                     const local = declareSymbol(container.locals, /*parent*/ undefined, node, exportKind, symbolExcludes);
                     local.exportSymbol = declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
                     node.localSymbol = local;
@@ -2288,7 +2284,7 @@ namespace ts {
             // When we create a property via 'exports.foo = bar', the 'exports.foo' property access
             // expression is the declaration
             setCommonJsModuleIndicator(node);
-            declareSymbol(file.symbol.exports, file.symbol, <PropertyAccessExpression>node.left, SymbolFlags.Property | SymbolFlags.Export, SymbolFlags.None);
+            declareSymbol(file.symbol.exports, file.symbol, <PropertyAccessExpression>node.left, SymbolFlags.Property | SymbolFlags.ExportValue, SymbolFlags.None);
         }
 
         function isExportsOrModuleExportsOrAlias(node: Node): boolean {
@@ -2329,7 +2325,7 @@ namespace ts {
 
             // 'module.exports = expr' assignment
             setCommonJsModuleIndicator(node);
-            declareSymbol(file.symbol.exports, file.symbol, node, SymbolFlags.Property | SymbolFlags.Export | SymbolFlags.ValueModule, SymbolFlags.None);
+            declareSymbol(file.symbol.exports, file.symbol, node, SymbolFlags.Property | SymbolFlags.ExportValue | SymbolFlags.ValueModule, SymbolFlags.None);
         }
 
         function bindThisPropertyAssignment(node: BinaryExpression) {

src/compiler/checker.ts

@@ -18800,7 +18800,7 @@ namespace ts {
                 // local symbol is undefined => this declaration is non-exported.
                 // however symbol might contain other declarations that are exported
                 symbol = getSymbolOfNode(node);
-                if (!(symbol.flags & SymbolFlags.Export)) {
+                if (!symbol.exportSymbol) {
                     // this is a pure local symbol (all declarations are non-exported) - no need to check anything
                     return;
                 }
@@ -18811,11 +18811,9 @@ namespace ts {
                 return;
             }
 
-            // we use SymbolFlags.ExportValue, SymbolFlags.ExportType and SymbolFlags.ExportNamespace
-            // to denote disjoint declarationSpaces (without making new enum type).
-            let exportedDeclarationSpaces = SymbolFlags.None;
-            let nonExportedDeclarationSpaces = SymbolFlags.None;
-            let defaultExportedDeclarationSpaces = SymbolFlags.None;
+            let exportedDeclarationSpaces = DeclarationSpaces.None;
+            let nonExportedDeclarationSpaces = DeclarationSpaces.None;
+            let defaultExportedDeclarationSpaces = DeclarationSpaces.None;
             for (const d of symbol.declarations) {
                 const declarationSpaces = getDeclarationSpaces(d);
                 const effectiveDeclarationFlags = getEffectiveDeclarationFlags(d, ModifierFlags.Export | ModifierFlags.Default);
@@ -18855,28 +18853,34 @@ namespace ts {
                 }
             }
 
-            function getDeclarationSpaces(d: Declaration): SymbolFlags {
+            const enum DeclarationSpaces {
+                None = 0,
+                ExportValue = 1 << 0,
+                ExportType = 1 << 1,
+                ExportNamespace = 1 << 2,
+            }
+            function getDeclarationSpaces(d: Declaration): DeclarationSpaces {
                 switch (d.kind) {
                     case SyntaxKind.InterfaceDeclaration:
                     case SyntaxKind.TypeAliasDeclaration:
-                        return SymbolFlags.ExportType;
+                        return DeclarationSpaces.ExportType;
                     case SyntaxKind.ModuleDeclaration:
                         return isAmbientModule(d) || getModuleInstanceState(d) !== ModuleInstanceState.NonInstantiated
-                            ? SymbolFlags.ExportNamespace | SymbolFlags.ExportValue
-                            : SymbolFlags.ExportNamespace;
+                            ? DeclarationSpaces.ExportNamespace | DeclarationSpaces.ExportValue
+                            : DeclarationSpaces.ExportNamespace;
                     case SyntaxKind.ClassDeclaration:
                     case SyntaxKind.EnumDeclaration:
-                        return SymbolFlags.ExportType | SymbolFlags.ExportValue;
+                        return DeclarationSpaces.ExportType | DeclarationSpaces.ExportValue;
                     case SyntaxKind.ImportEqualsDeclaration:
-                        let result = SymbolFlags.None;
+                        let result = DeclarationSpaces.None;
                         const target = resolveAlias(getSymbolOfNode(d));
                         forEach(target.declarations, d => { result |= getDeclarationSpaces(d); });
                         return result;
                     case SyntaxKind.VariableDeclaration:
                     case SyntaxKind.BindingElement:
                     case SyntaxKind.FunctionDeclaration:
                     case SyntaxKind.ImportSpecifier: // https://github.com/Microsoft/TypeScript/pull/7591
-                        return SymbolFlags.ExportValue;
+                        return DeclarationSpaces.ExportValue;
                     default:
                         Debug.fail((ts as any).SyntaxKind[d.kind]);
                 }

src/compiler/types.ts

@@ -2890,13 +2890,11 @@ namespace ts {
         TypeParameter           = 1 << 18,  // Type parameter
         TypeAlias               = 1 << 19,  // Type alias
         ExportValue             = 1 << 20,  // Exported value marker (see comment in declareModuleMember in binder)
-        ExportType              = 1 << 21,  // Exported type marker (see comment in declareModuleMember in binder)
-        ExportNamespace         = 1 << 22,  // Exported namespace marker (see comment in declareModuleMember in binder)
-        Alias                   = 1 << 23,  // An alias for another symbol (see comment in isAliasSymbolDeclaration in checker)
-        Prototype               = 1 << 24,  // Prototype property (no source representation)
-        ExportStar              = 1 << 25,  // Export * declaration
-        Optional                = 1 << 26,  // Optional property
-        Transient               = 1 << 27,  // Transient symbol (created during type check)
+        Alias                   = 1 << 21,  // An alias for another symbol (see comment in isAliasSymbolDeclaration in checker)
+        Prototype               = 1 << 22,  // Prototype property (no source representation)
+        ExportStar              = 1 << 23,  // Export * declaration
+        Optional                = 1 << 24,  // Optional property
+        Transient               = 1 << 25,  // Transient symbol (created during type check)
 
         Enum = RegularEnum | ConstEnum,
         Variable = FunctionScopedVariable | BlockScopedVariable,
@@ -2941,7 +2939,6 @@ namespace ts {
         BlockScoped = BlockScopedVariable | Class | Enum,
 
         PropertyOrAccessor = Property | Accessor,
-        Export = ExportNamespace | ExportType | ExportValue,
 
         ClassMember = Method | Accessor | Property,
 

src/services/importTracker.ts

@@ -440,7 +440,7 @@ namespace ts.FindAllReferences {
 
         function getExport(): ExportedSymbol | ImportedSymbol | undefined {
             const parent = node.parent!;
-            if (symbol.flags & SymbolFlags.Export) {
+            if (symbol.exportSymbol) {
                 if (parent.kind === SyntaxKind.PropertyAccessExpression) {
                     // When accessing an export of a JS module, there's no alias. The symbol will still be flagged as an export even though we're at the use.
                     // So check that we are at the declaration.
@@ -449,9 +449,7 @@ namespace ts.FindAllReferences {
                         : undefined;
                 }
                 else {
-                    const { exportSymbol } = symbol;
-                    Debug.assert(!!exportSymbol);
-                    return exportInfo(exportSymbol, getExportKindForDeclaration(parent));
+                    return exportInfo(symbol.exportSymbol, getExportKindForDeclaration(parent));
                 }
             }
             else {