Remove Super/ContainsSuper transform flags

Author: rbuckton

src/compiler/binder.ts

@@ -3088,19 +3088,18 @@ namespace ts {
 
     function computeCallExpression(node: CallExpression, subtreeFlags: TransformFlags) {
         let transformFlags = subtreeFlags;
+        const callee = skipOuterExpressions(node.expression);
         const expression = node.expression;
 
         if (node.typeArguments) {
             transformFlags |= TransformFlags.AssertTypeScript;
         }
 
-        if (subtreeFlags & TransformFlags.ContainsRestOrSpread
-            || (expression.transformFlags & (TransformFlags.Super | TransformFlags.ContainsSuper))) {
+        if (subtreeFlags & TransformFlags.ContainsRestOrSpread || isSuperOrSuperProperty(callee)) {
             // If the this node contains a SpreadExpression, or is a super call, then it is an ES6
             // node.
             transformFlags |= TransformFlags.AssertES2015;
-
-            if (expression.transformFlags & TransformFlags.ContainsSuper) {
+            if (isSuperProperty(callee)) {
                 transformFlags |= TransformFlags.ContainsLexicalThis;
             }
         }
@@ -3497,11 +3496,10 @@ namespace ts {
 
         // If a PropertyAccessExpression starts with a super keyword, then it is
         // ES6 syntax, and requires a lexical `this` binding.
-        if (transformFlags & TransformFlags.Super) {
-            transformFlags ^= TransformFlags.Super;
+        if (node.expression.kind === SyntaxKind.SuperKeyword) {
             // super inside of an async function requires hoisting the super access (ES2017).
             // same for super inside of an async generator, which is ES2018.
-            transformFlags |= TransformFlags.ContainsSuper | TransformFlags.ContainsES2017 | TransformFlags.ContainsES2018;
+            transformFlags |= TransformFlags.ContainsES2017 | TransformFlags.ContainsES2018;
         }
 
         node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
@@ -3510,16 +3508,13 @@ namespace ts {
 
     function computeElementAccess(node: ElementAccessExpression, subtreeFlags: TransformFlags) {
         let transformFlags = subtreeFlags;
-        const expression = node.expression;
-        const expressionFlags = expression.transformFlags; // We do not want to aggregate flags from the argument expression for super/this capturing
 
         // If an ElementAccessExpression starts with a super keyword, then it is
         // ES6 syntax, and requires a lexical `this` binding.
-        if (expressionFlags & TransformFlags.Super) {
-            transformFlags &= ~TransformFlags.Super;
+        if (node.expression.kind === SyntaxKind.SuperKeyword) {
             // super inside of an async function requires hoisting the super access (ES2017).
             // same for super inside of an async generator, which is ES2018.
-            transformFlags |= TransformFlags.ContainsSuper | TransformFlags.ContainsES2017 | TransformFlags.ContainsES2018;
+            transformFlags |= TransformFlags.ContainsES2017 | TransformFlags.ContainsES2018;
         }
 
         node.transformFlags = transformFlags | TransformFlags.HasComputedFlags;
@@ -3783,7 +3778,7 @@ namespace ts {
 
             case SyntaxKind.SuperKeyword:
                 // This node is ES6 syntax.
-                transformFlags |= TransformFlags.AssertES2015 | TransformFlags.Super;
+                transformFlags |= TransformFlags.AssertES2015;
                 excludeFlags = TransformFlags.OuterExpressionExcludes; // must be set to persist `Super`
                 break;
 

src/compiler/types.ts

@@ -5048,25 +5048,22 @@ namespace ts {
         ContainsES2017 = 1 << 4,
         ContainsES2016 = 1 << 5,
         ContainsES2015 = 1 << 6,
-        Generator = 1 << 7,
-        ContainsGenerator = 1 << 8,
-        DestructuringAssignment = 1 << 9,
-        ContainsDestructuringAssignment = 1 << 10,
+        ContainsGenerator = 1 << 7,
+        DestructuringAssignment = 1 << 8,
+        ContainsDestructuringAssignment = 1 << 9,
 
         // Markers
         // - Flags used to indicate that a subtree contains a specific transformation.
+        ContainsTypeScriptClassSyntax = 1 << 10,                // Decorators, Property Initializers, Parameter Property Initializers
         ContainsLexicalThis = 1 << 11,
-        ContainsTypeScriptClassSyntax = 1 << 12,                // Decorators, Property Initializers, Parameter Property Initializers
-        ContainsRestOrSpread = 1 << 13,
-        ContainsObjectRestOrSpread = 1 << 14,
-        ContainsComputedPropertyName = 1 << 15,
-        ContainsBlockScopedBinding = 1 << 16,
-        ContainsBindingPattern = 1 << 17,
-        ContainsYield = 1 << 18,
-        ContainsHoistedDeclarationOrCompletion = 1 << 19,
-        ContainsDynamicImport = 1 << 20,
-        Super = 1 << 21,
-        ContainsSuper = 1 << 22,
+        ContainsRestOrSpread = 1 << 12,
+        ContainsObjectRestOrSpread = 1 << 13,
+        ContainsComputedPropertyName = 1 << 14,
+        ContainsBlockScopedBinding = 1 << 15,
+        ContainsBindingPattern = 1 << 16,
+        ContainsYield = 1 << 17,
+        ContainsHoistedDeclarationOrCompletion = 1 << 18,
+        ContainsDynamicImport = 1 << 19,
 
         // Please leave this as 1 << 29.
         // It is the maximum bit we can set before we outgrow the size of a v8 small integer (SMI) on an x86 system.
@@ -5082,15 +5079,15 @@ namespace ts {
         AssertES2017 = ContainsES2017,
         AssertES2016 = ContainsES2016,
         AssertES2015 = ContainsES2015,
-        AssertGenerator = Generator | ContainsGenerator,
+        AssertGenerator = ContainsGenerator,
         AssertDestructuringAssignment = DestructuringAssignment | ContainsDestructuringAssignment,
 
         // Scope Exclusions
         // - Bitmasks that exclude flags from propagating out of a specific context
         //   into the subtree flags of their container.
-        OuterExpressionExcludes = DestructuringAssignment | Generator | HasComputedFlags,
-        PropertyAccessExcludes = OuterExpressionExcludes | Super,
-        NodeExcludes = PropertyAccessExcludes | ContainsSuper,
+        OuterExpressionExcludes = DestructuringAssignment | HasComputedFlags,
+        PropertyAccessExcludes = OuterExpressionExcludes,
+        NodeExcludes = PropertyAccessExcludes,
         ArrowFunctionExcludes = NodeExcludes | ContainsTypeScriptClassSyntax | ContainsBlockScopedBinding | ContainsYield | ContainsHoistedDeclarationOrCompletion | ContainsBindingPattern | ContainsObjectRestOrSpread,
         FunctionExcludes = NodeExcludes | ContainsTypeScriptClassSyntax | ContainsLexicalThis | ContainsBlockScopedBinding | ContainsYield | ContainsHoistedDeclarationOrCompletion | ContainsBindingPattern | ContainsObjectRestOrSpread,
         ConstructorExcludes = NodeExcludes | ContainsLexicalThis | ContainsBlockScopedBinding | ContainsYield | ContainsHoistedDeclarationOrCompletion | ContainsBindingPattern | ContainsObjectRestOrSpread,

src/compiler/utilities.ts

@@ -1473,6 +1473,11 @@ namespace ts {
         }
     }
 
+    export function isSuperOrSuperProperty(node: Node): node is SuperExpression | SuperProperty {
+        return node.kind === SyntaxKind.SuperKeyword
+            || isSuperProperty(node);
+    }
+
     /**
      * Determines whether a node is a property or element access expression for `super`.
      */